Clonamiento, expresión y seroreactividad de la proteína recombinante de ensamblaje de lipopolisacáridos - D (LptD) de Bartonella bacilliformis / Cloning, expression and seroreactivity of the recombinant lipopolysaccharide assembly protein - D (LptD) from Bartonella bacilliformis

RESUMEN Objetivo. Evaluar in silico y a nivel serológico el potencial antigénico del dominio extracelular recombinante de la proteína de ensamblaje de lipopolisacáridos - D (LptD) de Bartonella bacilliformis (dexr_LptD). Materiales y métodos. Mediante el análisis in silico se realizó la selección de una proteína de B. bacilliformis con potencial antigénico e inmunogénico. El gen de la proteína seleccionada se clonó en Escherichia coli TOP10 y se expresó en Escherichia coli BL21 (DE3) pLysS. La proteína recombinante fue expresada usando isopropil-β-D-1-tiogalactopiranósido (IPTG) y se optimizaron las condiciones de inducción. Por último, se purificó con resina Ni-IDA (His60 Ni Superflow) y se realizó un ensayo de Western Blot. Resultados. In silico, la proteína seleccionada fue LptD por estar localizada en la membrana externa y ser antigénica e inmunogénica. Las condiciones optimizadas para la inducción del dexr_LptD fueron 0,5 mM IPTG, 16 h, medio TB (Terrific Broth), etanol al 3% (v/v), 28 ºC, OD600: 1-1,5 y 200 r.p.m. La purificación se realizó en condiciones denaturantes a pequeña escala y se obtuvo 2,6 µg/mL de dexr_LptD parcialmente purificada. El ensayo de Western Blot mostró una reacción positiva entre los sueros provenientes de pacientes con la enfermedad de Carrión y dexr_LptD, ello evidencia la antigenicidad del dexr_LptD. Conclusiones. El dexr_LptD muestra antigenicidad in silico y a nivel serológico, estos resultados son base para posteriores estudios sobre candidatos vacunales contra la enfermedad de Carrión.

ABSTRACT Objective. To evaluate in silico and at the serological level the antigenic potential of the recombinant extracellular domain of the lipopolysaccharide assembly protein - D (LptD) of Bartonella bacilliformis (dexr_LptD). Materials and Methods. Through in silico analysis, we selected a B. bacilliformis protein with antigenic and immunogenic potential. The selected protein gene was cloned into Escherichia coli TOP10 and expressed in Escherichia coli BL21 (DE3) pLysS. Recombinant protein was expressed using isopropyl-β-D-1-thiogalactopyranoside (IPTG) and induction conditions were optimized. Finally, it was purified with Ni-IDA resin (His60 Ni Superflow) and a Western Blot assay was conducted. Results. In silico, the selected protein was LptD because it is located in the outer membrane and is antigenic and immunogenic. Optimized conditions for dexr_LptD induction were 0.5 mM IPTG, 16 hours, TB (Terrific Broth) medium, 3% (v/v) ethanol, 28 ºC, OD600: 1-1.5 and 200 rpm. Purification was carried out under denaturating conditions on a small scale and we obtained 2.6 μg/mL of partially purified dexr_LptD. The Western Blot assay showed a positive reaction between the sera from patients with Carrión's Disease and dexr_LptD, which shows the antigenicity of dexr_LptD. Conclusions. The dexr_LptD shows antigenicity both in silico and at the serological level, these results are the basis for further studies on vaccine candidates against Carrion's Disease.

Analysis of Agranulocytosis Time and Its Influencing Factors in Patients with Hematological Malignancies Treated with rhIL-11 combined rhG-CSF / 中国实验血液学杂志

OBJECTIVE@#To explore the intervention effect of recombinant human interleukin-11 (rhIL-11) and recombinant human granulocyte-colony stimulating factor (rhG-CSF) on the duration and severity of agranulocytosis in patients with hematological malignancies after chemotherapy, and to analyze the influencing factors.@*METHODS@#The data of hematological malignancy patients treated with rhIL-11 and rhG-CSF after chemotherapy in the hematology department of The First Hospital of Lanzhou University from July 2017 to July 2020 were collected retrospectively. The duration and differences of agranulocytosis in differeent groups were compared by univariate analysis, and the influencing factors of agranulocytosis duration were further analyzed by multiple regression analysis.@*RESULTS@#The duration of agranulocytosis in 97 patients was 6.47±2.93 days. The results of univariate analysis showed that there were no statistical differences in the duration of agranulocytosis among patients with different sex, age, height, weight, body surface area, body mass index (BMI), dose of rhG-CSF, dose of rhIL-11, spontaneous bleeding after administration of rhG-CSF and rhIL-11, and the duration of agranulocytosis in patients with different red blood cell count (RBC), hemoglobin(HGB) level, platelet count (PLT) and absolute neutrophil count (ANC), before administration of rhG-CSF and rhIL-11. There were significant differences in agranulocytosis time among patients with different disease types, chemotherapy cycle, fever after rhG-CSF and rhIL-11 administration, and different white blood cell count (WBC) baseline level before rhG-CSF and rhIL-11 administration (P＜0.05). Compared with patients with acute lymphoblastic leukemia (ALL) and non-Hodgkin lymphoma (NHL), patients with acute myeloid leukemia (AML) had the longest duration of agranulocytosis, which was 7.07±3.05 d. Compared with patients with chemotherapy cycles of 4－6 and ≥7, patients with total chemotherapy cycle of 1－3 had the shortest duration of agranulocytosis, which was 5.25±2.48 d. Compared with patients without fever, patients with fever within 1 day after administration of cytokines and patients with fever within 2-5 days after administration of cytokines, the duration of agranulocytosis was the longest in patients with fever 6 days after administration of cytokines, which was 8.85±2.85 d. Compared with patients with WBC baseline <1.0×109/L, (1.0－1.9)×109/L and (2.0－3.9)×109/L, patients with WBC baseline ≥4.0×109/L had the shortest duration of agranulocytosis, which was 4.50±2.56 d. Multiple linear regression analysis showed that chemotherapy cycle, different fever after administration of rhG-CSF and rhIL-11, diagnosis of ALL and NHL, and WBC baseline level before administration of rhG-CSF and rhIL-11 were the influencing factors of the duration of agranulocytosis (P＜0.001).@*CONCLUSION@#The risk of prolonged agranulocytosis is higher in patients diagnosed with AML, with more chemotherapy cycles, lower WBC baseline before cytokines administration and fever later after cytokines administration, which should be paid more attention to.

The Treatment of Newly Diagnosed Primary Immune Thrombocytopenia by Recombinant Human Thrombopoietin Combined with Glucocorticoid / 中国实验血液学杂志

OBJECTIVE@#To evaluate the efficacy and safety of recombinant human thrombopoietin (rhTPO) combined with glucocorticoid in treatment of newly diagnosed adult primary immune thrombocytopenia (ITP).@*METHODS@#Eleven male and 23 female patients with the diagnosis of primary ITP in our hospital from November 2018 to October 2019 were enrolled and randomly divided into test group (17 cases) and control group (17 cases), the median age was 52 years old (range: 20-76 years old). The patients in test group were treated with rhTPO 300 IU/(kg·d) combined with glucocorticoid , while the patients in control group were treated with rhTPO (15 000 IU/d) combined with glucocorticoid. Platelet count, platelet increase, as well as the overall response rate were compared. At the same time, the drug tolerance and any adverse drug reactions were observed.@*RESULTS@#The platelet counts and platelet increase of the patients in the test group were significantly higher than those in control group (P<0.05). There was no significant difference in platelet counts and platelet increase between the patients in the test group and control group at day 3, 7 after treatment. There was no significant difference in overall response rates and complete response rates at day 7, 14 between the two groups either. In test group, there were 13 cases received platelet transfusion, while 12 cases in control group. The muscle aches occurred in one patient, and mild aminotransferase increased in another patient in test group which was self-recovery without treatment.@*CONCLUSION@#RhTPO 300 U/(kg·d) combined with glucocorticoid could rapidly increase the platelet count with a low incidence of tolerable adverse events compared with conventional dose rhTPO with glucocorticoid.

Effect of rhTPO and rhIL-11 on Thrombocytopenia after Chemotherapy in Leukemia / 中国实验血液学杂志

OBJECTIVE@#To analyze and compare the efficacy of recombinant human thrombopoietin (rhTPO) and recombinant human interleukin-11 (rhIL-11) in the treatment of thrombocytopenia after chemotherapy in acute leukemia patients.@*METHODS@#180 patients with acute leukemia complicated with thrombocytopenia after chemotherapy in the First Affiliated Hospital of Anhui Medical University were analyzed retrospectively. Among them, 50 patients who treated with rhTPO and did not receive platelet transfusion were set as group A, 50 patients treated with rhTPO and receive platelet transfusion were set as group B, Forty patients treated with rhIL-11 without platelet transfusion were set as group C, Forty patients who treated with rhIL-11 and received platelet transfusion were set as group D. The duration of PLT below 20×109/L, the days it takes for PLT to recover to more than 100×109/L, and the incidence of different bleeding degrees were compared among several groups.@*RESULTS@#The duration of PLT<20×109/L in group A(3.72±1.14 d) was significantly shorter than that in group C(4.93±1.33 d) (P<0.001), and there was no significant difference from group B (P>0.05). The duration of PLT<20×109/L in group B(3.06±0.91 d) was significantly shorter than that in group D(4.65±0.98 d) (P<0.001), while the difference in duration of days between group C and D was not statistically significant (P>0.05). The times for PLT to recover to 100×109/L in group A(13.46±1.67 d) were significantly shorter than that in group C(16.85±2.13 d) (P<0.05), but there was no significant difference from group B (P>0.05). The time required for PLT to recover to 100×109/L in group B(13.36±1.49 d) were significantly shorter than that in group D(16.18±1.78 d) (P<0.05), while the difference in the days required for group C and group D was not statistically significant (P>0.05). The incidence of high bleeding risk in group B was significantly lower than that in group A (22% vs 44%, P<0.05), the incidence of high bleeding risk in group D was significantly lower than that in group C (32% vs 65%, P<0.05), and the incidence of high bleeding risk in group A was significantly lower than that in group C (44% vs 65%, P<0.05). The incidence of high bleeding risk in group B(22%) was lower than that in group D(32.5%), and the difference was not statistically significant (P>0.05).@*CONCLUSION@#In the treatment of acute leukemia patients with thrombocytopenia after chemotherapy, compared with rhIL-11, rhTPO can significantly shorten the duration for patients in a status with extremely low levels of PLT and the recovery time of PLT to normal range. In addition, PLT transfusion cannot speed up the time for patients to raise platelets to a safe range, nor can it shorten the duration of low PLT levels, but it can reduce the incidence of high bleeding risk events.

Studies on the recombinant production and anticancer activity of thermostable L- asparaginase I from Pyrococcus abyssi / Estudos sobre a produção recombinante e atividade anticancerígena da L-asparaginase I termoestável de Pyrococcus abyssi

L-Asparaginase catalysing the breakdown of L-Asparagine to L-Aspartate and ammonia is an enzyme of therapeutic importance in the treatment of cancer, especially the lymphomas and leukaemia. The present study describes the recombinant production, properties and anticancer potential of enzyme from a hyperthermophilic archaeon Pyrococcus abyssi. There are two genes coding for asparaginase in the genome of this organism. A 918 bp gene encoding 305 amino acids was PCR amplified and cloned in BL21 (DE3) strain of E. coli using pET28a (+) plasmid. The production of recombinant enzyme was induced under 0.5mM IPTG, purified by selective heat denaturation and ion exchange chromatography. Purified enzyme was analyzed for kinetics, in silico structure and anticancer properties. The recombinant enzyme has shown a molecular weight of 33 kDa, specific activity of 1175 U/mg, KM value 2.05mM, optimum temperature and pH 80°C and 8 respectively. No detectable enzyme activity found when L-Glutamine was used as the substrate. In silico studies have shown that the enzyme exists as a homodimer having Arg11, Ala87, Thr110, His112, Gln142, Leu172, and Lys232 being the putative active site residues. The free energy change calculated by molecular docking studies of enzyme and substrate was found as ∆G ­ 4.5 kJ/mole indicating the affinity of enzyme with the substrate. IC50 values of 5U/mL to 7.5U/mL were determined for FB, caco2 cells and HepG2 cells. A calculated amount of enzyme (5U/mL) exhibited 78% to 55% growth inhibition of caco2 and HepG2 cells. In conclusion, the recombinant enzyme produced and characterized in the present study offers a good candidate for the treatment of cancer. The procedures adopted in the present study can be prolonged for in vivo studies.

A L-asparaginase, que catalisa a degradação da L-asparagina em L-aspartato e amônia, é uma enzima de importância terapêutica no tratamento do câncer, especialmente dos linfomas e da leucemia. O presente estudo descreve a produção recombinante, propriedades e potencial anticancerígeno da enzima de Pyrococcus abyssi, um archaeon hipertermofílico. Existem dois genes que codificam para a asparaginase no genoma desse organismo. Um gene de 918 bp, que codifica 305 aminoácidos, foi amplificado por PCR e clonado na cepa BL21 (DE3) de E. coli usando o plasmídeo pET28a (+). A produção da enzima recombinante foi induzida sob 0,5mM de IPTG, purificada por desnaturação seletiva por calor e cromatografia de troca iônica. A enzima purificada foi analisada quanto à cinética, estrutura in silico e propriedades anticancerígenas. A enzima recombinante apresentou peso molecular de 33 kDa, atividade específica de 1.175 U / mg, valor de KM 2,05 mM, temperatura ótima de 80º C e pH 8. Nenhuma atividade enzimática detectável foi encontrada quando a L-glutamina foi usada como substrato. Estudos in silico mostraram que a enzima existe como um homodímero, com Arg11, Ala87, Thr110, His112, Gln142, Leu172 e Lys232 sendo os resíduos do local ativo putativo. A mudança de energia livre calculada por estudos de docking molecular da enzima e do substrato foi encontrada como ∆G ­ 4,5 kJ / mol, indicando a afinidade da enzima com o substrato. Valores de IC50 de 5U / mL a 7,5U / mL foram determinados para células FB, células caco2 e células HepG2. Uma quantidade de enzima (5U / mL) apresentou inibição de crescimento de 78% a 55% das células caco2 e HepG2, respectivamente. Em conclusão, a enzima recombinante produzida e caracterizada no presente estudo é uma boa possibilidade para o tratamento do câncer. Os procedimentos adotados na presente pesquisa podem ser aplicados para estudos in vivo.

Desenvolvimento de teste diagnóstico não invasivo capaz de detectar anticorpos anti-SARS-CoV-2 em urina / Development of a non-invasive diagnostic test capable of detecting anti-SARS-CoV-2 antibodies in urine

A plataforma de ELISA (ensaio de imunoabsorção por ligação enzimática) tem sido amplamente utilizada para detectar anticorpos anti-SARS-CoV-2 gerados após a exposição ao vírus ou à vacinação. A amostra comumente utilizada para a realização do teste é o soro. Até o momento, nenhum estudo havia investigado a urina do paciente como amostra para detectar anticorpos específicos para o vírus SARS-CoV-2. A urina é um espécime biológico que traz vantagens significativas inerentes ao tipo de amostra, que compreende coleta não invasiva, de fácil manuseio e armazenamento. Neste trabalho, propomos um ELISA indireto in house baseado no uso de urina e proteínas recombinantes do Nucleocapsídeo (N) ou da Spike (S) do vírus SARS-CoV-2. As proteínas recombinantes (r) de SARS-CoV-2, N e as subunidades da proteína S (S-Glic, S1-NGlic e RBD-NGlic), foram avaliadas usando um painel composto por aproximadamente 200 amostras de urina e de soro. A presença de anticorpos anti-SARS-CoV-2 na urina foi detectada com sensibilidade e especificidade similares ou superiores ao soro, nas quais foram obtidos valores de sensibilidade de 94,0%, 75,0%, 81,38% e 89,66%, e especificidade de 100%, 96,0%, 96,77% e 96,77%, frente às proteínas rSARS-CoV-2 N, S-Glic, S1-NGlic e RBDNGlic, respectivamente. Dessa forma, os dados apresentados sugerem que a urina poderia ser considerada como uma potencial amostra biológica para aplicação em plataformas de imunodiagnóstico para a infecção por SARS-CoV-2, trazendo benefícios tanto no contexto individual quanto populacional.

The Enzyme-linked immunosorbent assay (ELISA) method has been widely used to detect anti-SARS-CoV-2 antibodies generated after exposure to the virus or vaccination. The sample usually used to perform the test is the serum. Thus far, no study has investigated the urine of patients as biological sample to detect specific SARS-CoV-2 antibodies. Urine is a biological specimen with significant advantages inherent to the type of sample, which comprises non-invasive collection, easy handling and storage. In this work, we propose an in house urine-based indirect ELISA using recombinant proteins from Nucleocapsid (N) and Spike (S) of the SARSCoV-2 virus. SARS-CoV-2 recombinant N and S protein subunits (Gly-S, NonGly-S1 and NonGly-RBD) were evaluated in an ELISA platform with a panel composed about 200 urine and serum samples. The presence of anti-SARS-CoV-2 antibodies in urine was detected with similar or superior sensitivity and specificity to serum, in which sensitivity values of 94.0%, 75.0%, 81.38% and 89.66% were obtained, while specificity values were of 100.0%, 96.0%, 96.77% and 96.77%, respectively, against rSARS-CoV-2 N, S-Glic, S1-NGlic and RBD-NGlic proteins. In conclusion, the data presented suggest that urine could be considered as a potential biological sample for application in immunodiagnostic platforms for SARS-CoV-2 infection, with benefits to the individual and population context.

Construction of recombinant adenovirus expressing capsid protein of serotype O foot-and-mouth disease virus and analysis of its immunogenicity / 生物工程学报

In order to construct a recombinant replication deficient human type 5 adenovirus (Ad5) expressing a foot-and-mouth disease virus (FMDV) capsid protein, specific primers for P12A and 3B3C genes of FMDV-OZK93 were synthesized. The P12A and 3B3C genes were then amplified and connected by fusion PCR, and a recombinant shuttle plasmid pDC316-mCMV-EGFP-P12A3B3C expressing the FMDV-OZK93 capsid protein precursor P12A and 3B3C protease were obtained by inserting the P12A3B3C gene into the pDC316-mCMV-EGFP plasmid. The recombinant adenovirus rAdv-P12A3B3C-OZK93 was subsequently packaged, characterized and amplified using AdMaxTM adenovirus packaging system, and the expression was verified by infecting human embryonic kidney cell HEK-293. The humoral and cellular immunity levels of well-expressed and purified recombinant adenovirus immunized mice were evaluated. The results showed that rAdv-P12A3B3C-OZK93 could be stably passaged and the maximum virus titer reached 1×109.1 TCID50/mL. Western blotting and indirect immunofluorescence showed that rAdv-P12A3B3C-OZK93 expressed the FMDV-specific proteins P12A and VP1 in HEK-293 cells. In addition, the PK cell infection experiment confirmed that rAdv-P12A3B3C-OZK93 could infect porcine cells, which is essential for vaccination in pigs. Comparing with the inactivated vaccine group, the recombinant adenovirus could induce higher FMDV-specific IgG antibodies, γ-IFN and IL-10. This indicates that the recombinant adenovirus has good immunity for animal, which is very important for the subsequent development of foot-and-mouth disease vaccine.

Preparation of a recombinant tumor-targeting ribosome inactivating protein luffin-α-NGR and evaluation of its antitumor activity / 生物工程学报

Loofah seeds ribosome inactivating protein luffin-α was fused with a tumor-targeting peptide NGR to create a recombinant protein, and its inhibitory activity on tumor cells and angiogenesis were assessed. luffin-α-NGR fusion gene was obtained by PCR amplification. The fusion gene was ligated with pGEX-6p-1 vector to create a recombinant plasmid pGEX-6p-1/luffin-α-NGR. The plasmid was transformed into E. coli BL21, and the target protein was isolated and purified by GST affinity chromatography. The luffin-α-NGR fusion gene with a full length of 849 bp was successfully obtained, and the optimal soluble expression of the target protein was achieved under the conditions of 16 ℃, 0.5 mmol/L IPTG after 16 h induction. SDS-PAGE and Western blotting confirmed the recombinant protein has an expected molecular weight of 56.6 kDa. Subsequently, the recombinant protein was de-tagged by precision protease digestion. The inhibitory effects of the recombinant protein on liver tumor cells HepG2 and breast cancer cells MDA-MB-231 were significantly stronger than that of luffin-α. The Transwell and CAM experiment proved that the recombinant protein luffin-α-NGR also had a significant inhibitory effect on tumor cells migration and neovascularization. The inhibitory activity on tumor cells and angiogenesis of the recombinant luffin-α-NGR protein lays a foundation for the development of subsequent recombinant tumor-targeting drugs.

Preparation and characterization of Ad-ERα-36-Fc-GFP / 生物工程学报

ERα-36 is a novel subtype of estrogen receptor α which promotes tumor cell proliferation, invasion and drug resistance, and it serves as a therapeutic target. However, only small-molecule compounds targeting ERα-36 are under development as anticancer drugs at present. Gene therapy approach targeting ERα-36 can be explored using recombinant adenovirus armed with decoy receptor. The recombinant shuttle plasmid pDC316-Ig κ-ERα-36-Fc-GFP was constructed via genetic engineering to express an Ig κ-signaling peptide-leading secretory recombinant fusion protein ERα-36-Fc. The recombinant adenovirus Ad-ERα-36-Fc-GFP was subsequently packaged, characterized and amplified using AdMaxTM adenovirus packaging system. The expression of fusion protein and functional outcome of Ad-ERα-36-Fc-GFP transduction were further analyzed with triple-negative breast cancer MDA-MB-231 cells. Results showed that the recombinant adenovirus Ad-ERα-36-Fc-GFP was successfully generated. The virus effectively infected MDA-MB-231 cells which resulted in expression and secretion of the recombinant fusion protein ERα-36-Fc, leading to significant inhibition of EGFR/ERK signaling pathway. Preparation of the recombinant adenovirus Ad-ERα-36-Fc-GFP provides a basis for further investigation on cancer gene therapy targeting ERα-36.

Prokaryotic expression of a recombinant protein of adeno-associated virus capsid conserved regions and preparation of its polyclonal antibody / 南方医科大学学报

OBJECTIVE@#To express and purify the antigenic peptide of adeno-associated virus (AAV) capsid conserved regions in prokaryotic cells and prepare its rabbit polyclonal antibody.@*METHODS@#The DNA sequence encoding the conserved regions of AAV capsid protein was synthesized and cloned into the vector pET30a to obtain the plasmid pET30a-AAV-CR for prokaryotic expression and purification of the conserved peptides. Coomassie blue staining and Western blotting were used to identify the AAV conserved peptides. Japanese big ear white rabbits were immunized with AAV conserved region protein to prepare polyclonal antibody, with the rabbits injected with PBS as the control group. The antibody titer was determined with ELISA, and the performance of the antibody for recognizing capsid protein sequences of AAV1-AAV10 was assessed with Western blotting and immunofluorescence assay.@*RESULTS@#The plasmid pET30a-AAV-CR was successfully constructed, and a recombinant protein with a relative molecular mass of 17000 was obtained. The purified protein induced the production of antibodies against the conserved regions of AAV capsid in rabbits, and the titer of the purified antibodies reached 1:320 000. The antibodies were capable of recognizing a wide range of capsid protein sequences of AAV1-AAV10.@*CONCLUSION@#We successfully obtained the polyclonal antibodies against AAV capsid conserved region protein from rabbits, which facilitate future studies of AAV vector development and the biological functions of AAV.

Diagnostic value of serum tumor markers CEA, CYFRA21-1, SCCAg, NSE and ProGRP for lung cancers of different pathological types / 南方医科大学学报

OBJECTIVE@#To evaluate the diagnostic value of the serum tumor markers carcinoembryonic antigen (CEA), cytokeratin-19-fragment (CYFRA21-1), squamous cell carcinoma associated antigen (SCCAg), neuron-specificenolase (NSE) and pro-gastrin-releasing peptide (ProGRP) for lung cancers of different pathological types.@*METHODS@#This study was conducted among patients with established diagnoses of lung adenocarcinoma (LADC, n=137), lung squamous cell carcinoma (LSCC, n=82), small cell lung carcinoma (SCLC, n=59), and benign chest disease (BCD, n=102). The serum tumor markers were detected for all the patients for comparison of the positivity rates and their serum levels. ROC curve was used for analysis of the diagnostic efficacy of these tumor markers either alone or in different combinations.@*RESULTS@#In patients with LADC, the positivity rate and serum level of CEA were significantly higher than those in the other groups (P < 0.05); the patients with LSCC had the highest positivity rate and serum level of SCCAg among the 4 groups (P < 0.05). The positivity rates and serum levels of ProGRP and NSE were significantly higher in SCLC group than in the other groups (P < 0.05). CYFRA21-1 showed the highest positivity rate and serum level in LADC group and LSCC group. With the patients with BCD as control, CEA showed a diagnostic sensitivity of 62.8% and a specificity of 93.1% for LADC, and the sensitivity and specificity of SCCAg for diagnosing LSCC were 64.6% and 91.2%, respectively. CYFRA21-1 had the highest diagnostic sensitivity for LADC and LSCC. The diagnostic sensitivity and specificity of ProGRP for SCLC were 83.1% and 98.0%, respectively. When combined, CYFRA21-1 and CEA showed a high sensitivity (78.8%) and specificity (86.3%) for diagnosing LADC with an AUC of 0.891; CYFRA21-1 and SCCAg had a high sensitivity (84.1%) and specificity (87.3%) for diagnosing LSCC with an AUC of 0.912. NSE combined with ProGRP was highly sensitive (88.1%) and specific (98.0%) for diagnosis of SCLC, with an AUC of 0.952. For lung cancers of different pathological types, the combination of all the 5 tumor markers showed no significant differences in the diagnostic power from a combined detection with any two of the markers (P>0.05).@*CONCLUSION@#CEA, CYFRA21-1, SCCAg, NSE and ProGRP are all related to the pathological type of lung cancers and can be used in different combinations as useful diagnostic indicators for lung cancers.

Effect of artificial liver with double plasma molecular absorb system model on patients' platelets and corresponding treatment strategy / 北京大学学报(医学版)

OBJECTIVE@#To compare the effects of artificial liver treatment with double plasma molecular adsorption system(DPMAS) mode and traditional plasma exchange (PE) mode on platelets in patients, and to evaluate the clinical efficacy of recombinent human thrombopoietin (rhTPO) in the treatment of thrombocytopenia.@*METHODS@#A total of fifteen patients undergoing artificial liver with DPMAS model admitted to the Fifth Affiliated Hospital of Guangzhou Medical University from January 2018 to November 2020 were selected and included in the DPMAS group, and another 15 patients receiving PE were selected and included in the PE group. The improvement of clinical symptoms, such as fatigue, jaundice, oliguria, edema, etc. before and after artificial liver treatment was compared between the two groups, and the trend of blood routine (especially platelet), coagulation function and other indexes before and after treatment were compared between the two groups. The use of rhTPO and the number of platelets were recorded during treatment.@*RESULTS@#The improvement rate of clinical symptoms in DPMAS group was 86.67%, which was higher than that in PE group, but the difference was not statistically significant (P>0.05). There was no statistical significance in the outcome of the two groups within 90 days (P>0.05). There was no significant difference in white blood cell (WBC) and hemoglobin (HB) between the two groups after treatment (P>0.05). However, the level of platelet(PLT) in DPMAS group was significantly lower than that before treatment (P < 0.05), and was significantly lower than that in PE group (P < 0.05). After treatment, the international normalized ratio (INR) level in PE group was significantly improved (P < 0.05), but there was no significant difference in the INR level in DPMAS group (P>0.05). The patients in the DPMAS group received an average of (8.2±3.1) doses of rhTPO and (1.5±0.3) IU of platelet transfusions during hospitalization. In DMPAS group, platelets increased significantly after infusion of terbium.@*CONCLUSION@#Compared with PE mode, the artificial liver with DPMAS mode can reduce platelet levels in patients, but the application of rhTPO can stimulate platelet regeneration and increase platelet levels in the patients, thereby reducing the risk of bleeding due to platelet hypoplasia.

Effects of methacrylic anhydride gelatin hydrogel loaded with silver and recombinant human basic fibroblast growth factor on deep partial-thickness burn wounds in rabbits / 中华烧伤杂志

Objective: To investigate the effects of methacrylic anhydride gelatin (GelMA) hydrogel loaded with silver and recombinant human basic fibroblast growth factor (rh-bFGF) on deep partial-thickness burn wounds in rabbits. Methods: The experimental research method was adopted. Low-concentration GelMA materials, medium-concentration GelMA materials and high-concentration GelMA materials containing different concentrations of methacrylic anhydride (MA) were prepared, after adding photoinitiator, low-concentration GelMA hydrogels, medium-concentration GelMA hydrogels, and high-concentration GelMA hydrogels were obtained, respectively. The nuclear magnetic resonance spectroscopy was performed to detect the hydrogen nuclear magnetic resonance spectra of the above-mentioned three concentrations of GelMA materials, and to calculate the degree of substitution according to the spectrum diagram. The three-dimensional microstructure and pore size of 3 types of above-mentioned GelMA hydrogels were detected by field emission scanning electron microscopy (FESEM), with 9 samples measured. According to the selected concentration of MA, ten kinds of solutions of GelMA with different concentration of silver (silver-containing GelMA) were synthesized, and the silver-containing GelMA solution of each concentration was divided into three parts, and then exposed to ultraviolet light lasting for 20, 25, and 35 s, respectively. After adding photoinitiator,the corresponding silver-containing GelMA hydrogels were obtained. The residual degradation rate of silver-containing GelMA hydrogel with different photocrosslinking times was detected by collagenase degradation method at degradation of 12, 24, 36, and 48 h; and the time required for complete degradation was detected, and the sample number was 5. The inhibition zone diameter of GelMA hydrogel under above screened photocrosslinking times containing 10 concentrations of silver against Staphylococcus aureus was measured to reflect its antibacterial ability, and the sample numbers were all 5. The silver-containing GelMA hydrogel with statistical significance compared with the antibacterial circle diameter of the silver-containing GelMA hydrogel containing the lowest concentration (no silver) was considered as having antibacterial activity. The three-dimensional microstructure and pore size of the silver-containing GelMA hydrogels with antibacterial activity and the lowest drug concentration selected were detected by FESEM, and the sample numbers were all 9. The freeze-dried alone GelMA hydrogel and the freeze-dried silver-containing GelMA hydrogel were soaked in phosphate buffer solution for 24 h, respectively, then the swelling rate of the two GelMA hydrogel were calculated and compared by weighing method, and the sample number was 5. GelMA hydrogel containing silver and rh-bFGF, namely compound hydrogel for short, was prepared according to the preliminary experiment and the above experimental results. The appearance of the composite hydrogel was observed in general, and its three-dimensional microstructure and pore size were detected by FESEM. The deep partial-thickness burn wound was made on the back of 30 rabbits (aged 4-6 months, female half and half). Meanwhile, with the rabbit head as the benchmark, the wounds on the left side of the spine were treated as composite hydrogel treatment group, and the wounds on the right side were treated as gauze control group, and which were treated accordingly. On post injury day (PID) 3, 7, 14, 21, and 28, the healing of wounds in the two groups was observed. On PID 7, 14, 21, and 28, the wound healing area was recorded and the healing rate was calculated, with a sample number of 30. Data were statistically analyzed with analysis of variance for repeated measurement, one-way analysis of variance, and independent sample t test. Results: The substitution degree among low-concentration GelMA materials, medium-concentration GelMA materials, and high-concentration GelMA materials was significantly different (F=1 628.00, P<0.01). The low-concentration GelMA hydrogel had a loose and irregular three-dimensional spatial network structure with a pore size of (60±17) μm; the medium-concentration GelMA hydrogel had a relatively uniform three-dimensional spatial network and pore size with a pore size of (45±13) μm; the high-concentration GelMA hydrogel had the dense and disordered three-dimensional spatial network with a pore size of (25±15) μm, the pore sizes of 3 types of GelMA hydrogels were significantly differences (F=12.20, P<0.01), and medium concentration of MA was selected for the concentration of subsequent materials. The degradability of silver-containing GelMA hydrogels with different concentrations of the same photocrosslinking time was basically same. The degradation residual rates of silver-containing GelMA hydrogels with 20, 25, and 35 s crosslinking time at 12 h were (74.2±1.7)%, (85.3±0.9)%, and (93.2±1.2)%, respectively; the residual rates of degradation at 24 h were (58.3±2.1)%, (65.2±1.8)%, and (81.4±2.6)%, respectively; the residual rates of degradation at 36 h were (22.4±1.9)%, (45.2±1.7)%, and (68.1±1.4)%, respectively; the residual rates of degradation at 48 h were (8.2±1.7)%, (32.4±1.3)%, and (54.3±2.2)%, respectively, and 20, 25, and 30 s photocrosslinking time required for complete degradation of silver-containing GelMA hydrogels were (50.2±2.4), (62.4±1.4), and (72.2±3.2) h, and the difference was statistically significant (F=182.40, P<0.01), 25 s were selected as the subsequent photocrosslinking time. The antibacterial diameters of 10 types of silver-containing GelMA hydrogels against Staphylococcus aureus from low to high concentrations were (2.6±0.4), (2.5±0.4), (3.2±0.4), (12.1±0.7), (14.8±0.7), (15.1±0.5), (16.2±0.6), (16.7±0.5), (16.7±0.4), and (16.7±0.6) mm, respectively, and which basically showed a concentration-dependent increasing trend, and the overall difference was statistically significant (F=428.70, P<0.01). Compared with the silver-containing GelMA hydrogel with the lowest concentration, the antibacterial circle diameters of other silver-containing GelMA hydrogels with antibacterial ability from low to high concentration were significantly increased (with t values of 26.35, 33.84, 43.65, 42.17, 49.24, 55.74, and 43.72, respectively, P<0.01). The silver-containing GelMA hydrogel with the antibacterial diameter of (12.1±0.7) mm had the lowest antibacterial activity against Staphylococcus aureus and the lowest drug loading concentration, and the concentration of silver was selected for the concentration of subsequent materials. The microscopic morphology of the silver-containing GelMA hydrogel containing silver element with a pore size of (45±13) μm had a regular and linear strip-like structure. After soaking for 24 h, the swelling ratio of silver-containing GelMA hydrogel was similar to that of alone GelMA hydrogel. The composite hydrogel was colorless, clear and transparent, and its three-dimensional microstructure was a regular and uniform grid, with a filament network structure inside, and the pore size of (40±21) μm. On PID 3, a large amount of necrotic tissue and exudate of rabbit wound in composite hydrogel group were observed, and scattered scabs, a small amount of necrotic tissue and exudate of rabbit wound in gauze control group were observed. On PID 7, the area of rabbit wound in composite hydrogel group was significantly reduced, and adhesion of rabbit wound and gauze in gauze control group was observed. On PID 14, In composite hydrogel group, the rabbit wound surface was ruddy, and the growth of granulation tissue was observed, and in gauze control group, the rabbit wound base was pale, and the blood supply was poor. On PID 21, the rabbit wounds in composite hydrogel group healed completely, and rabbit wound in gauze control group had healing trend. On PID 28, new hair could be seen on rabbit wound surface in composite hydrogel group; oval wound of rabbit in gauze control group still remained. On PID 7, 14, 21, and 28, the wound healing areas of rabbit in composite hydrogel group were significantly larger than those in gauze control group (with t values of 2.24, 4.43, 7.67, and 7.69, respectively, P<0.05 or P<0.01). Conclusions: The medium-concentration GelMA hydrogel has good physical and chemical properties in terms of swelling and degradability. The screened silver-containing GelMA hydrogels had the lowest antibacterial activity and the lowest drug loading concentration. Composite hydrogel can significantly shorten the healing time of deep partial-thickness burn wounds in rabbits.

Molecular cloning and characterization of three phenylalanine ammonia-lyase genes from Schisandra chinensis / 中国天然药物

Phenylalanine ammonia-lyase (PAL), which catalyzes the conversion from L-phenylalanine to trans-cinnamic acid, is a well-known key enzyme and a connecting step between primary and secondary metabolisms in the phenylpropanoid biosynthetic pathway of plants and microbes. Schisandra chinensis, a woody vine plant belonging to the family of Magnoliaceae, is a rich source of dibenzocyclooctadiene lignans exhibiting potent activity. However, the functional role of PAL in the biosynthesis of lignan is relatively limited, compared with those in lignin and flavonoids biosynthesis. Therefore, it is essential to clone and characterize the PAL genes from this valuable medicinal plant. In this study, molecular cloning and characterization of three PAL genes (ScPAL1-3) from S. chinensis was carried out. ScPALs were cloned using RACE PCR. The sequence analysis of the three ScPALs was carried out to give basic characteristics followed by docking analysis. In order to determine their catalytic activity, recombinant protein was obtained by heterologous expression in pCold-TF vector in Escherichia coli (BL21-DE3), followed by Ni-affinity purification. The catalytic product of the purified recombinant proteins was verified using RP-HPLC through comparing with standard compounds. The optimal temperature, pH value and effects of different metal ions were determined. Vmax, Kcat and Km values were determined under the optimal conditions. The expression of three ScPALs in different tissues was also determined. Our work provided essential information for the function of ScPALs.

Del ARN mensajero a los vectores virales y las proteínas recombinantes: la evolución de las vacunas contra COVID-19 / From messenger RNA to viral vectors and recombinant proteins: the evolution of vaccines against COVID-19

Entre finales de 2019 y mediados de 2022, la pandemia de COVID-19 ha causado más de 600 millones de casos confirmados y al menos 6,5 millones de muertes, constituyendo la emergencia de salud pública más importante de las últimas décadas. En paralelo con el transcurso de la pandemia, ha tenido lugar una carrera sin precedentes por la obtención de vacunas eficaces para el control de la rápida dispersión del virus. Cuatro meses después del anuncio de la emergencia del SARS-CoV-2, agente de la pandemia, ya habían 115 "vacunas candidatas", cinco de ellas en fase de ensayos clínicos [1]. Al mismo tiempo, una gran revolución en la producción de vacunas estaba ocurriendo; nuevas tecnologías de producción de biológicos, más eficaces y más rápidas, llevaron al desarrollo de vacunas útiles en un tiempo increíblemente corto. Antes de la pandemia, el desarrollo de una nueva vacuna típicamente solía tomar entre cinco y diez años, pero en 2020, a menos de un año de haberse declarado la pandemia, ya se habían publicado ensayos clínicos que demostraban la eficacia de varias vacunas producidas mediante tecnologías novedosas [2]. Son numerosas las vacunas contra el SARS-CoV-2 que han sido autorizadas para su uso. A la fecha, más de 12 mil millones de dosis de vacunas han sido administradas en el mundo [3]. Se estima que tres dosis de vacunas pueden evitar hasta en un 94 % el riesgo de uso de ventilación mecánica y muerte [4], así mismo, estudios demuestran que el riesgo de mortalidad por COVID-19 en los no vacunados es 25 veces mayor que en los vacunados

Usos de la levadura Pichia pastoris en la producción de proteínas recombinantes / Uses of Pichia pastoris yeast in the production of recombinant proteins

La levadura metilotrófica Pichia pastoris (clasificada actualmente como Komagataella phaffii) es una de las más importantes para la producción de proteínas heterólogas. En el trabajo se presenta un análisis de las principales características que se ponen de manifiesto en la expresión de proteínas recombinantes expresadas en este microorganismo. Se describen las cepas disponibles para la transformación y producción de proteínas recombinantes expresadas en Pichia pastoris, los principales vectores comerciales para la expresión, los promotores más eficientes, los marcadores seleccionables, la señal de secreción, los métodos usados en las transformaciones genéticas y los patrones de glicosilación que se presentan. Se brindan recomendaciones generales acerca de los parámetros de bioprocesos como la composición del medio, el pH, la temperatura, la velocidad de aireación, la inducción y las estrategias de alimentación para alcanzar altos valores de productividad. Se presentan los resultados de las aplicaciones de Pichia pastoris en la producción de dos vacunas en Cuba, la vacuna contra la hepatitis B y la vacuna para el control de la garrapata(AU)

Pichia pastoris metylotrofic yeast (currently classified as Komagataella phaffii) is one of the most important yeast for the production of heterologous proteins. The work presents an analysis of the main characteristics that are marked in the production of recombinant proteins expressed in Pichia pastoris. It describes the strains available for the transformation and production of recombinant proteins expressed in P. pastoris, the main commercial vectors for expression, the most efficient promoters, selectable markers, the secretion signal, the methods used in genetic transformations and glycosylation patterns that occur. General recommendations are provided on bioprocess parameters such as media composition, pH, temperature, aeration velocity, induction, and feeding strategies to achieve high productivity values. The results of Pichia pastoris applications for the production of two vaccines in Cuba, the hepatitis B vaccine and the tick control vaccine are shown(AU)

Major cardiovascular adverse events in Fabry disease patients receiving agalsidase alfa / Eventos cardiovasculares mayores en pacientes con enfermedad de Fabry tratados con agalsidasa alfa

Abstract Cardiovascular mortality (CVM) has become the major contributor to overall Fabry disease (FD) mortality in the enzyme replacement therapy (ERT) era. Our objectives were to describe causes and potential predictors of mortality in FD adult patients in Argentina, and to assess risk of major adverse cardio vascular events (MACE) in the ERT era. We retrospectively studied 93 consecutive patients treated with alpha-galactosidase A (median follow up: 9.5 years from start of ERT). Mean age at ERT starting was 35±16.3 years. Prevalence of cardiomyopathy and renal disease reached 47% and 41%, respectively. Eleven subjects (11.8%, 95%CI: 5-18%) died during follow up (1.24/100 patient-years). Mean overall survival was 71 years (95%CI: 66-75 years). Seven cases were considered as CVM; main causes were sudden death and stroke. Risk of MACE was 14% (95%CI: 6.9-21.1%; 1.47 events/100 patient-years from start of ERT). All but 2 subjects had at least one comorbid cardiovascular risk factor; however, 86% of patients remained free of MACE during follow-up. CVM remained low and our study was underpowered for detection of predictors of mortality, but it is worth noting that age at diagnosis and ERT starting, left ventricular mass index and renal disease trended to correlate with CVM. Prevalence of hypertension, diabetes and dyslipidemia were lower in FD patients when compared to population level data. As in the Argentinean general population, CVM was the leading cause of mortality among this cohort of consecutive FD patients treated with agalsidase alfa.

Resumen La mortalidad cardiovascular (MCV) se ha convertido en el principal contribuyente a la mortalidad general por enfermedad de Fabry (EF) en la era de la terapia de reemplazo enzimático (TRE). Nuestros objetivos fueron describir las causas y posibles predictores de mortalidad en pacientes adultos con EF en la Argentina, y evaluar el riesgo de eventos cardiovasculares mayores (MACE) en la actual era de TRE. Se estudiaron 93 pacientes consecutivos tratados con agalsidasa-alfa por una mediana de 9.5 años tras iniciar TRE. La edad al inicio de TRE fue 35 ± 16.3 años. La prevalencia de cardiomiopatía y enfermedad renal alcanzó 47% y 41%, respectivamente. Once sujetos (11.8%; IC95%: 5-18%) murieron durante el seguimiento (1.24/100 pacientes/año). La supervivencia global fue 71 años (IC95%: 66-75 años). Siete casos fueron considerados como MCV; las principales causas fueron muerte súbita e ictus. El riesgo de MACE fue 14% (IC95%: 6.9-21.1%; 1.47 eventos/100 pacientes/año desde la ERT). Todos menos 2 sujetos tenían al menos un factor de riesgo cardiovascular, pero el 86% permaneció libre de MACE. Los eventos de MCV fueron escasos. El estudio tuvo reducido poder estadístico para detectar predictores de mortalidad, pero la edad al diagnóstico y al iniciar la TRE, índice de masa ventricular izquierda y enfermedad renal tendieron a correlacionarse con MCV. La prevalencia de hipertensión, diabetes y dislipidemia fue menor en comparación con la población general. Como ocurre con la población general en Argentina, los eventos cardiovasculares fueron la principal causa de muerte en esta cohorte de pacientes consecutivos con EF tratados con agalsidasa-alfa.

Plastid transformation: advances and challenges for its implementation in agricultural crops

Chloroplast biotechnology has emerged as a promissory platform for the development of modified plants to express products aimed mainly at the pharmaceutical, agricultural, and energy industries. This technology's high value is due to its high capacity for the mass production of proteins. Moreover, the interest in chloroplasts has increased because of the possibility of expressing multiple genes in a single transformation event without the risk of epigenetic effects. Although this technology solves several problems caused by nuclear genetic engineering, such as turning plants into safe bio-factories, some issues must still be addressed in relation to the optimization of regulatory regions for efficient gene expression, cereal transformation, gene expression in non-green tissues, and low transformation efficiency. In this article, we provide information on the transformation of plastids and discuss the most recent achievements in chloroplast bioengineering and its impact on the biopharmaceutical and agricultural industries; we also discuss new tools that can be used to solve current challenges for their successful establishment in recalcitrant crops such as monocots.

Expression of recombinant PreS2-S protein from the hepatitis B virus surface antigen in Pichia pastoris

The aim of this work is the expression of the PreS2-S region of surface antigen of hepatitis B virus (HBV) in yeast Pichia pastoris. A cDNA fragment encoding the Pres2-S protein of HBV was cloned to yeast transfer vectors. Based on cloned new plasmids pPIC3.5-PreS2-S (8707 bp) and pPIC9-PreS2-S (8980 bp) the recombinant strains of P. pastoris producing the PreS2-S region of surface antigen of HBV were obtained. The PAGE electrophoresis and immunoblotting of obtained recombinant PreS2-S protein confirm the molecular weight (34 kDa) and high specificity to the HBV antibodies)AU)

El objetivo de este trabajo es la expresión de la región PreS2-S del antígeno de superficie del virus de la hepatitis B en la levadura Pichia pastoris. Se clonó un fragmento de ADNc que codifica la proteína PreS2-S del VHB en vectores de transferencia de levadura. A partir de los nuevos plásmidos clonados pPIC3.5-PreS2-S (8707 pb) y pPIC9-PreS2-S (8980 pb) se obtuvieron las cepas recombinantes de P. pastoris productoras de la región PreS2-S del antígeno de superficie del VHB. La electroforesis PAGE y la inmunotransferencia de la proteína PreS2-S recombinante obtenida confirman el peso molecular (34 kDa) y la alta especificidad a los anticuerpos contra el VHB(AU)

Mejora tecnológica del proceso de llenado aséptico para la producción de la vacuna Antihepatitis B recombinante / Improvement of the aseptic filling process for the production of recombinant hepatitis vaccine

Frente a la creciente demanda de producción de la vacuna Antihepatitis B recombinante, constituye un reto para el Centro Nacional de Biopreparados aumentar la fabricación del producto, para lo cual el proceso de llenado aséptico requirió de una inversión. En el trabajo se presenta la selección de la nueva máquina llenadora y se calculan los indicadores económicos asociados a la inversión, la que se recupera en el cuarto año con una ganancia de $2.655.300. Luego de la inversión se evaluó el desempeño de la nueva máquina y se comparó con los resultados anteriores a la inversión. Se compararon los valores de volumen dispensado por vial, velocidad de llenado, rendimiento operacional, principales defectos detectados en los lotes de llenado, tiempo promedio de llenado de un lote, costo de producción y comportamiento del monto resarcido al cliente por rechazos de producto. El volumen dispensado por vial resulta más exacto, reduciendo las pérdidas de producto. La velocidad de llenado aumenta 1,7 veces respecto a la máquina anterior. El rendimiento operacional aumenta en un 13,63 percent. Disminuyen los rechazos de producto en 40.897 viales, representando un ahorro de $24.538 ingresados en 73 lotes producidos. Se ahorra en energía eléctrica un total de $14.718 en un mes. El costo unitario del proceso de llenado disminuye en 0,0648 $/vial(AU)

National Center for Biopreparations must increase the production of the recombinant hepatitis B vaccine because of its growing demand. In order to fulfill this challenge, the aseptic filling process required an investment. This work, presents the selection of the new filling machine and the economic indicators that support the investment. Inversion cost is recovered in the fourth year with a profit equivalent to $2,655,300. After the investment, the performance of the new machine was compared with the previous one. Volume dispensed per vial, filling speed, operational performance, major defects detected in filling batches, average filling time for a batch, production cost and payments to customers due to rejected products were compared. The control of the volume dispensed per vial is more accurate, reducing product losses. The filling speed increases 1.7 times compared to the previous machine. Operational performance increases by 13.63 percent. Product rejections are reduced by 40,897 vials, saving $24,538 for the 73 batches. Electricity consumption diminished, saving $14,718 monthly. The unit cost of the filling process decreases by $0.0648/vial(AU)