High-level expression of anti FLAG tag antibody in plants / 生物工程学报

Plant bioreactor is a new production platform for expression of recombinant protein, which is one of the cores of molecular farming. In this study, the anti DYKDDDDK (FLAG) antibody was recombinantly expressed in tobacco (Nicotiana benthamiana) and purified. FLAG antibody with high affinity was obtained after immunizing mice for several times and its sequence was determined. Based on this, virus vectors expressing heavy chain (HC) and light chain (LC) inoculated into Nicotiana benthamiana leaves by using Agrobacterium-mediated delivery. Accumulation of the HC and LC was analyzed by SDS/PAGE followed by Western blotting probed with specific antibodies from 2 to 9 days postinfiltration (dpi). Accumulation of the FLAG antibody displayed at 3 dpi, and reached a maximum at 5 dpi. It was estimated that 66 mg of antibody per kilogram of fresh leaves could be obtained. After separation and purification, the antibody was concentrated to 1 mg/mL. The 1:10 000 diluted antibody can probe with 1 ng/mL FLAG fused antigen well, indicating the high affinity of the FLAG antibody produced in plants. In conclusion, the plant bioreactor is able to produce high affinity FLAG antibodies, with the characteristics of simplicity, low cost and highly added value, which contains enormous potential for the rapid and abundant biosynthesis of antibodies.

Development and verification of a detection method for activity of neutralizing antibody in ELISA antibody positive serum of rats immunized with recombinant human interleukin-1 receptor antagonist / 中国生物制品学杂志

@#Objective To develop and verify a method for detecting the activity of neutralizing antibodies in ELISA antibody positive serum of rats immunized with recombinant human interleukin-1 receptor antagonist(rhIL-1Ra). Methods The SD rats were subcutaneously immunized with 3,20 and 100 mg/kg rhIL-1Ra injection respectively,10 rats in each group,half male and half female,twice a day at an interval of at least 4 h between each dose for 13 consecutive weeks. The blood samples were collected from the jugular vein of rats during the administration period and the recovery period. The serum samples were isolated and detected for the antibody titers by ELISA,and the samples positive for rhIL-1Ra antibody were purified by Protein A chromatographic column. Based on,D10G4·1 cells biological activity assay,a method for the detection of neutralizing antibody activity was developed and verified for the specificity,sensitivity and precision. The neutralizing antibody activity of rhIL-1Ra antibody positive serum determined by ELISA was detected by using the developed method.Results With the increase of doses,the serum antibody titers of rats in various dose groups gradually increased,and there were still antibodies in the recovery period,and the titer was still high. Rabbit anti-rhIL-1Ra monoclonal antibody showed obvious neutralizing effect on rIL-1Ra,while rabbit anti-rIFN-2b monoclonal antibody had no dose-effect relationship with rIL-1Ra. The sensitivity of the method was 171. 93 μg/mL;The CVs of precision verification were not more than 20%. The positive antibody sera detected by ELISA all had neutralizing effect on rhIL-1Ra injection,which was consistent with the results detected by ELISA. Conclusion The method developed in this study has good specificity and high sensitivity in the detection of serum neutralizing antibody activity in rats immunized with rhIL-1Ra,which can be used to detect the serum neutralizing antibody activity of animals with rhIL-1Ra repeated administration.

Establishment and validation of bioactivity measurement method for recombinant human midkine / 药学学报

To establish and optimize a method for the detection of recombinant human midkine (rhMK) activity and verify its methodology, cell counting kit-8 (cck-8) method was used to measure the proliferation activity of rat knee chondrocytes. The specificity, accuracy, precision, linearity and robustness of the method were also verified in this study. The established method was proven to have good specificity because the buffer of rhMK and recombinant human interleukin-1 receptor antagonist have no obvious active effect; the recoveries of the samples with relative activities of 50%, 75%, 100%, 125%, 150% were in the range of 80.0% to 124.0% by statistical analysis, the relative standard deviations (RSD) of relative potency were all within 20%, the linear correlation coefficient, R2 ≥ 0.98, suggesting that the accuracy, precision and linearity of the method were good; the robustness correlation coefficient, R2 ≥ 0.92 and the ratio of maximum to minimum of sigmoidal dose-response were no less than 1.5, indicating that robustness of the methods was good. In conclusion, a bioactivity measurement method for rhMK was established and fully validated in this study and it provides a reliable method for the bioactivity analysis of rhMK routine samples during the development. This study was approved by the Animal Care and Use Committee of Shanghai Model Organisms Center, Inc. (approval number: 2019-0008-06).

Expression, purification, and functional verification of recombinant human glycoprotein hormone beta 5/alpha 2 fusion protein in CHO-S cells / 中国药理学通报

Aim To express and purify recombinant hCGH-CTP fusion protein in high-density suspension culture of Chinese hamster ovary cells (CHO-S), and to verify the lipid accumulation effect of rhCGH-CTP on 3T3-L1 mature adipocytes. Methods The recombinant protein expression vector (pcDNA3. 1-rhCGH-CTP) was constructed, achieved by fusing the human glycoprotein hormone beta 5/alpha 2 cDNA with CTP Linker. The expression plasmid was transiently transfected into the suspended CHO-S to express rhCGH-CTP protein and then purified, and the protein biological activity was verified. Intervention with 3T3-L1 mature adipocyte cells for 24 h was performed to detect the changes of intracellular triglyceride (TG) level. Results Western blot results showed that rhCGH-CTP protein was successfully expressed in CHO-S cells, and the yield was up to 715. 4 mg • L~ . The secreted protein was purified by AKTA pure system with higher purity that was up to 90% as identified by SDS-PAGE. In addition, the intracellular cAMP content of mature adipocytes with high expression of TSHR gene significantly increased after intervention with different concentrations of rhCGH-CTP protein by ELISA kit, indicating that rhCGH-CTP protein had biological activity. Oil red 0 staining showed that compared with the control group, the lipid content of mature adipocytes in the intervention groups with different concentrations of rhCGH-CTP protein significantly decreased (P < 0. 05) . Conclusions The rhCGH-CTP protein has been successfully expressed and purified with biological activity, and effectively reduce TG. This research provides an important theoretical basis for further revealing the physiological role of CGH protein and its potential application in clinical practice.

Application value of bone cement containing rhbFGF and RHBMP-2 in PKP treatment of osteoporotic lumbar compression fracture / 中国骨伤

OBJECTIVE@#To investigate the effect of bone cement containing recombinant human basic fibroblast growth factor (rhbFGF) and recombinant human bone morphogenetic protein-2 (rhBMP-2) in percutaneous kyphoplasty(PKP)treatment of osteoporotic vertebral compression fracture(OVCF).@*METHODS@#A total of 103 OVCF patients who underwent PKP from January 2018 to January 2021 were retrospectively analyzed, including 40 males and 63 females, aged from 61 to 78 years old with an average of (65.72±3.29) years old. The injury mechanism included slipping 33 patients, falling 42 patients, and lifting injury 28 patients. The patients were divided into three groups according to the filling of bone cement. Calcium phosphate consisted of 34 patients, aged(65.1±3.3) years old, 14 males and 20 females, who were filled with calcium phosphate bone cement. rhBMP-2 consisted of 34 patients, aged (64.8±3.2) years old, 12 males and 22 females, who were filled with bone cement containing rhBMP-2. And rhbFGF+rhBMP-2 consisted of 35 patients, aged (65.1±3.6) years old, 14 males and 21 females, who were filled with bone cement containing rhbFGF and rhBMP-2. Oswestry disability index (ODI), bone mineral density, anterior edge loss height, anterior edge compression rate of injured vertebra, visual analog scale (VAS) of pain, and the incidence of refracture were compared between groups.@*RESULTS@#All patients were followed for 12 months. Postoperative ODI and VAS score of the three groups decreased (P<0.001), while bone mineral density increased (P<0.001), anterior edge loss height, anterior edge compression rate of injured vertebra decreased first and then slowly increased (P<0.001). ODI and VAS of group calcium phosphate after 1 months, 6 months, 12 months were lower than that of rhBMP-2 and group rhbFGF+rhBMP-2(P<0.05), bone mineral density after 6 months, 12 months was higher than that of rhBMP-2 and group calcium phosphate(P<0.05), and anterior edge loss height, anterior edge compression rate of injured vertebra of group rhbFGF+rhBMP-2 after 6 months and 12 months were lower than that of group rhBMP-2 and group calcium phosphate(P<0.05). There was no statistical difference in the incidence of re-fracture among the three groups (P>0.05).@*CONCLUSION@#Bone cement containing rhbFGF and rhBMP-2 could more effectively increase bone mineral density in patients with OVCF, obtain satisfactory clinical and radiological effects after operation, and significantly improve clinical symptoms.

Effect of treatment with growth hormone on body composition and metabolic profile of short children born small for gestational age / Efeito do tratamento com hormônio de crescimento na composição corporal e no perfil metabólico de crianças nascidas pequenas para a idade gestacional com baixa estatura

ABSTRACT Objective: To assess the effect of recombinant growth hormone (rGH) on body composition and metabolic profile of prepubertal short children born small for gestational age (SGA) before and after 18 months of treatment. Methods: It is a clinical, non-randomized, and paired study. Children born SGA, with birth weight and/or length <-2 standard deviations (SD) for gestational age and sex, prepubertal, born at full term, of both genders, with the indication for treatment with rGH were included. The intervention was performed with biosynthetic rGH at doses ranging from 0.03 to 0.05 mg/kg/day, administered subcutaneously, once a day at bedtime. Total lean mass (LM) and total fat mass (FM) were carried out using dual-energy X-ray absorptiometry (DXA), and the metabolic profile was assessed for insulin, glycemia, IGF-1 levels and lipid profile. Results: Twelve patients (nine girls, 8.17±2.39 y) were evaluated; three patients dropped out of the study. There was an increase of LM adjusted for length (LMI) (p=0.008), LMI standard deviation score (SDS) adjusted for age and sex (p=0.007), and total LM (p<0.001). The percentage of body fat (BF%) and abdominal fat (AF) remained unaltered in relation to the beginning of treatment. Among the metabolic variables, blood glucose remained within normal levels, and there was a reduction in the number of participants with altered cholesterol (p=0.023). Conclusions: The effect of rGH treatment was higher on LM than in FM, with increased LM adjusted for length and standardized for age and sex. Glycemia remained within the normal limits, and there was a decreased number of children with total cholesterol above the recommended levels.

RESUMO Objetivo: Avaliar o efeito do hormônio de crescimento recombinante (rHC) na composição corporal e no perfil metabólico de crianças pré-púberes com baixa estatura, nascidas pequenas para a idade gestacional (PIG) antes e depois de 18 meses de tratamento. Métodos: Estudo clínico, não randomizado e pareado. Foram incluídas crianças nascidas PIG, com peso e/ou altura ao nascer <-2 desvios padrão (DP) para idade gestacional e sexo, pré-púberes, nascidas a termo, de ambos os sexos, com indicação de tratamento com rGH. A intervenção foi realizada com rGH biossintético com doses variando de 0,03 a 0,05 mg/kg/dia, administrado por via subcutânea, uma vez ao dia ao deitar-se. A massa magra total (LM) e a massa gorda total (MG) foram determinadas por meio de absorciometria de raios X de dupla energia (DXA), e o perfil metabólico foi avaliado com dosagens de insulina, glicemia, IGF-1 e perfil lipídico. Resultados: Doze pacientes (nove meninas, 8,17±2,39 anos) foram avaliados; três pacientes abandonaram o estudo. Houve aumento da LM ajustada para estatura (LMI) (p=0,008), LMI standard deviation scores (SDS) ajustada para idade e sexo (p=0,007) e LM total (p<0,001). O percentual de gordura corporal (GC%) e gordura abdominal (AF) permaneceu inalterado em relação ao início do tratamento. Entre as variáveis metabólicas, a glicemia manteve-se na normalidade, e houve redução do número de participantes com colesterol alterado (p=0,023). Conclusões: O efeito do tratamento com HCr foi maior na MM do que na MG, com o aumento da MM ajustada para altura e padronizada para idade e sexo. A glicemia permaneceu normal e houve redução do número de crianças com colesterol total acima do recomendado.

Obtención de la proteína verde fluorescente recombinante y su anticuerpo policlonal Igy

La Proteína Verde Fluorescente (Green Fluorescent Protein, GFP) es ampliamente utilizada en ensayos in vivo e in vitro. Se han generado múltiples variantes de esta proteína para diversificar sus características, como la GFP-enhancer (EGFP) que emite una señal de fluorescencia 35 veces mayor en comparación con la proteína silvestre, siendo implementada como proteína fusión en estudios de localización y estabilidad estructural, entre otros. La detección de esta proteína y sus variantes puede ser directa o indirecta, mediante el uso de anticuerpos anti-GFP. Aunque el uso de GFP es generalizado y de evidente utilidad en investigación y en docencia, los insumos para su estudio exhiben un alto costo dado que deben ser importados, constituyendo un recurso limitado en Colombia. El presente trabajo reporta la clonación y expresión de la proteína recombinante 6xHisEGFP, cuya purificación se completó a partir de la fracción soluble e insoluble del sistema heterólogo Escherichia coli mediante cromatografía de afinidad a metales inmovilizados y electroforesis preparativa, respectivamente. La proteína purificada se implementó como antígeno para la producción de anticuerpos policlonales aviares (IgY) contra la EGFP, los cuales se obtuvieron desde los huevos colectados y el suero de las sangrías de las gallinas inmunizadas. En este sentido, la estrategia metodológica planteada constituye un avance en el desarrollo de un sistema biotecnológico para la producción nacional de herramientas moleculares como los anticuerpos policlonales aviares a bajo costo.

Green Fluorescent Protein (GFP) is widely used in in vivo and in vitro assays. Multiple variants of this protein have been generated to diversify its characteristics, such as the enhancer GFP (EGFP) that emits a 35-fold higher fluorescence signal compared to the wild-type protein, being implemented as a fusion reporter in localization and structural stability studies, among others. Detection of this protein can be direct or indirect, fusing anti-GFP antibodies. Although the use of GFP is generalized and of evident utility in research and teaching, the molecular tools for its study exhibit a high cost since they must be imported, constituting a limited resource in Colombia. This work reports the cloning and expression of the recombinant protein 6xHisEGFP, which purification was completed from the soluble and insoluble fraction of the heterologous Escherichia coli system by immobilized metal affinity chromatography and preparative SDS-PAGE, respectively. The purified protein was implemented as an antigen to produce avian polyclonal antibodies (IgY) against EGFP, which were obtained from collected eggs and blood serum from immunized hens. In this sense, the proposed methodological strategy constitutes an advance in the development of a biotechnological system for the national production of molecular tools such as avian polyclonal antibodies at low-cost.

The Use of Escherichia coli for Recombinant Human Insulin Production

Insulin is the essential hormone produced by the pancreas. which is accountable for sanctioning glucose we acquire from our food sources to be deposited in our body cells. Without insulin, our bodies cannot control blood sugar levels, so insulin is a vital hormone for survival. A diabetic person either does not produce insulin or is resilient to it for a multiple reasons. Because of this, they need insulin injections to process glucose. It has become stress-free for patients around the world to acquire insulin with the production of recombinant human insulin produced by Escherichia coli . This short review will provide an overview of the steps engaged in constructing recombinant human insulin utilizing the K12 strain of E. coli along with the prominence of recombinant insulin and why E. coli is most commonly used for insulin production.

Osteometabolic profile and bone mass in the transition phase: ethnic differences in Brazilians treated with somatropin during childhood

Abstract Objective: The main growth hormone action is to promote linear growth increasing protein synthesis stimulation and osteoblastic activity. Peak bone mass extends from adolescence to 30 years of age. Several factors may influence this acquisition and prevent fracture risk in adulthood, such as genetic potential, GH, ethnicity, and lifestyle factors. This study aims to compare bone mass and osteometabolic profile of white and Afro-descendant Brazilian adolescents in the transition phase, who were treated with human recombinant growth hormone in childhood. Methods: The authors selected 38 adolescents from the Transition Outpatient Clinic of the University of São Paulo. Lumbar spine and total body bone mineral density (BMD) and bone mineral content (BMC), serum calcium, 25-OH-vitamin D and bone markers were analyzed at the rhGH withdrawal. Results: The mean age was 16.8 ± 1.6 years. There were 21 Afro-descendant and 17 whites. Thirty-four percent of the sample presented vitamin D insufficiency, 66% inadequate calcium intake and 44.7% physical inactivity. The Afro-descendants showed a lower lumbar spine and total body Z scores than those of the whites (p = 0.04 and p = 0.03, respectively), as well as their mean body weight (p = 0.03). There were no differences in the remaining osteometabolic parameters. Conclusion: As most adolescents had vitamin D insufficiency, low calcium intake, and physical inactivity, calcium, and cholecalciferol supplementation and lifestyle changes should be encouraged. The Brazilian Afro-descendant may be a vulnerable group for low bone mass, requiring

Successful outcomes of surgery procedures in patient with Glanzmann´s Thrombasthenia

We report a 35-year-old female patient with Glanzmann's thrombasthenia (GT) and severe anemia due to abnormal uterine bleeding secondary to uterine myomatosis. She required several admissions of red blood cells and platelet transfusions. An elective subtotal hysterectomy with salpingo-oophorectomy was proposed and recombinant factor VII was required. Surgical and postoperative outcomes were successful, without surgical complications, bleeding, or hemogram alterations. 4 years later, she required tooth extraction because of periodontal disease and pulp necrosis. In Peru, reports of GT patients requiring major and minor surgical procedures are lacking, given the low disease prevalence and the difficulties related to surgery. The report of these successful cases becomes relevant to continue improving GT management.

Presentamos el caso de una paciente de 35 años con trombastenia de Glanzmann (GT) y anemia severa por sangrado uterino anormal secundario a miomatosis uterina. Requirió varias admisiones de transfusiones de glóbulos rojos y plaquetas. Se propuso histerectomía subtotal electiva con salpingo-ooforectomía y se requirió factor VII recombinante. Los resultados quirúrgicos y postoperatorios fueron exitosos, sin complicaciones quirúrgicas, sangrado ni alteraciones del hemograma. 4 años después, requirió extracción dental por enfermedad periodontal y necrosis pulpar. En Perú faltan reportes de pacientes con GT que requieran procedimientos quirúrgicos mayores y menores, dada la baja prevalencia de la enfermedad y las dificultades relacionadas con la cirugía. El reporte de estos casos de éxito cobra relevancia para seguir mejorando la gestión de GT

Angioedema after rt-PA infusion led to airway emergency: a case report of rescue treatment with fresh frozen plasma

Abstract The authors report the case of a 71-year-old woman presented to the Emergency Department with acute ischemic stroke. She was treated with rt-PA and interventional endovascular revascularization and developed rapidly progressing angioedema that led to emergency intubation. The standard treatment was not very effective and the swelling improved after infusion of fresh frozen plasma. Angioedema after rt-PA infusion could be a life-threatening emergency that requires quick airway management by skilled professionals. As this condition is triggered by several factors, such as unregulated histamine and bradykinin production, the traditional treatment recommended by the guidelines may not be sufficient and the use of FFP can be considered as a safe and valuable aid.

Molecular characterization & recombination analysis of complete enterovirus-88 isolated from acute flaccid paralysis cases in India

Background & objectives: Focus on non-polio enteroviruses (NPEVs) causing acute flaccid paralysis (AFP) due to myelitis has increased with the containment of the poliovirus. Enterovirus-B88 (EV-B88) has been associated with the AFP cases in Bangladesh, Ghana, South Africa, Thailand and India. In India, EV-B88 infection was linked to AFP a decade ago; however, to date, no complete genome has been made available. In this study, the complete genome sequence of EV-B88 was identified and reported from two different States (Bihar and Uttar Pradesh) in India using the next-generation sequencing technique. Methods: Virus isolation was performed on the three AFP suspected cases as per the WHO-recommended protocol. Samples showing cytopathic effects in the human Rhabdocarcinoma were labelled as NPEVs. Next-generation sequencing was performed on these NPEVs to identify the aetiological agent. The contiguous sequences (contigs) generated were identified, and reference-based mapping was performed. Results: EV-B88 sequences retrieved in our study were found to be 83 per cent similar to the EV-B88 isolate from Bangladesh in 2001 (strain: BAN01-10398; Accession number: AY843306.1). Recombination analyses of these samples demonstrate recombination events with sequences from echovirus-18 and echovirus-30. Interpretation & conclusions: Recombination events in the EV-B serotypes are known, and this work reconfirms the same for EV-B88 isolates also. This study is a step in increasing the awareness about EV-B88 in India and emphasizes future studies to be conducted in the identification of other types of EV present in India.

Clinical observation of herombopag combined with recombinant human thrombopoietin in the treatment of primary immune thrombocytopenia / 中国药房

OBJECTIVE To investigate the clinical efficacy and safety of herombopag combined with recombinant human thrombopoietin （rhTPO） in the treatment of primary immune thrombocytopenia （ITP） in the real world. METHODS A retrospective study was conducted on the patients diagnosed with ITP in the Second Affiliated Hospital of Bengbu Medical College from January 2021 to December 2022. Among them， 98 patients who were treated with a combination of herombopag and rhTPO were included in the observation group， and 157 patients who were treated with rhTPO alone were included in the control group. The changes in platelet count， clinical efficacy， bleeding， platelet transfusion rate and adverse drug reactions before and after treatment were observed and compared between the two groups. RESULTS Since the 8th day of treatment， there was a statistically significant difference in platelet count between the two groups （[ 61.04±13.46）×109 L－1 in observation group， （52.11±12.06）× 109 L－1 in control group] （P＜0.05）， and there also was a statistically significant difference in the peak and stable values of platelet count between the two groups （P＜0.05）. The total effective rates of the observation group and the control group were 79.59% and 66.88%， with cumulative response rates of 81.32% and 68.68%， and median response durations of 8 days and 10 days， respectively； these differences were statistically significant （P＜0.05）. During the treatment period， the bleeding rates of the observation group and control group were 3.06% and 8.28% （P＜0.05）， bleeding events were categorized as grade 1 or 2， and platelet transfusion rates were 31.63% and 40.76%； the differences in bleeding rates and platelet transfusion rates between the two groups was statistically significant （P＜0.05）. The incidences of adverse drug reactions in the two groups were 11.22% and 9.55%， respectively， with no statistically significant difference （P＞0.05）， and no moderate to severe adverse drug reaction was found. CONCLUSIONS The combination of herombopag and rhTPO can significantly increase platelet levels and response rate， and reduce bleeding rate and platelet transfusion rate in ITP patients， with good safety.

Development of national standards for genomic titer determination of recombinant type 5 adeno-associated virus / 中国生物制品学杂志

@#ObjectiveTo develop a national standard for genomic titer determination of recombinant type 5 adeno-associated virus(rAAV5).MethodsThe rAAV5-GFP stock solution prepared by the three-plasmid system was identified and verified for the appearance,pH,sterility,genomic titer,purity and infection titer according to the relevant requirements of Chinese Pharmacopoeia(Volume Ⅲ,2020 edition),which was diluted and subpackaged to prepare candidate standards according to the results;The stability of candidate standards was investigated by thermal acceleration test;Three laboratories were organized to collaboratively calibrate the candidate standards using droplet digital PCR(ddPCR).ResultsAll the detection indexes of the candidate standard and the stock solution met the relevant requirements;The genomic titer showed no significant decrease at 25,4,-20,-40,-80 ℃ for 1,3,4,6 months;Through collaborative calibration by three laboratories,the candidate standard was assigned a value of 2. 56 × 10(12)copies/mL,and the 95% confidence interval was 2. 48 ×10(12)copies/mL,and the 95% confidence interval was 2. 48 ×10(12)copies/mL ～ 2. 64 × 10(12)copies/mL ～ 2. 64 × 10(12)copies/mL.ConclusionThe developed national standard for the determination of rAAV5 genomic titer had good stability and might be used for the quality evaluation of rAAV5 related products.

Development of uniform antigen content detection kit for recombinant SARS-CoV-2 protein vaccines / 中国生物制品学杂志

@#Objective To prepare and verify a uniform antigen content detection kit for recombinant protein vaccines against severe acute respiratory syndrome coronavirus 2(SARS-CoV-2). Methods Using goat anti-S protein polyclonal antibody prepared by National Institutes for Food and Drug Control(NIFDC) as coating antibody,one of four monoclonal antibodies(14C8,15F9,17A7 and 20D8)with high receptor-binding domain(RBD)binding activity and broad-spectrum resistance against major variants as HRP-labeled antibody,a uniform double-antibody sandwich ELISA kit for antigen content detection of recombinant SARS-CoV-2 vaccine was prepared,and the dilution of coating antibody(1∶125 ～ 1∶4 000)and enzymelabeled antibody(1∶250 ～ 1∶32 000)were optimized by chessboard titration. The specificity,linear range,accuracy,precision and durability of the kit were verified. The prepared uniform detection kits were distributed to 12 laboratories to detect15 batches of recombinant SARS-CoV-2 protein vaccine stock solutions(including 11 batches of stock solutions designed with WT strain and 4 batches of designed with Beta,Gamma and Delta variants as reference sequence)from different expression systems(CHO cells,Pichia pastoris,Sf9 cells or E. coli)and target proteins(RBD or S protein)prepared by each laboratory.Results Monoclonal antibody 20D8 was used as the enzyme-labeled antibody with the optimal dilution of 1 : 4 000,and the optimal dilution of coating antibody was 1 : 500. The uniform detection kit showed no cross reaction with recombinant S protein of severe acute respiratory syndrome(SARS)and Middle East respiratory syndrome(MERS). The first generation national standard for recombinant SARS-CoV-2 protein vaccine antigen(national standard for short)showed a concentration of 0. 16 ～ 2. 50 U/mL with a good linear relationship with A450/630,and the linear equation was:y = 0. 791 x-0. 100 4,R2= 0. 993 7;The recoveries of 0. 16 ～ 2. 50 U/mL national standard in 6 repeated tests were 95% ～ 104% and the coefficients of variation(CVs)were less than 15%;The CVs in 3 repeated tests by 2 experimenters at different time were 4. 4% ～6. 6% and the recoveries were in the range of 80% ～ 120% under different temperature and time conditions. The antigen content of 15 batches of recombinant SARS-CoV-2 protein vaccine stock solutions showed good parallelism with the national standard. Conclusion The uniform detection kit for antigen content developed in this study had good specificity,accuracy,precision and durability,and might be used for the detection of antigen content of recombinant SARS-CoV-2 protein vaccines.

Application of Design of Experiment in development of purification process of recombinant human growth hormone-Fc fusion protein / 中国生物制品学杂志

@#ObjectiveTo optimize the condition for anion exchange chromatography in purification process of recombinant human growth hormone-Fc(rhGH-Fc)fusion protein by Design of Experiment(DOE)so as to decrease the content of host cell protein(HCP)in bulk of protein.MethodsA complete factorial experimental design with four factors at two levels was established by the DOE in Minitab 19 software.The condition(flow rate,sample load,pH value of buffer and salt concentration of eluent)for anion exchange chromatography in purification process of rhGH-Fc was optimized by DOE to find out the operating space.ResultsThe experimental results were predicted accurately by the established DOE model.The sample load,pH value of buffer,salt concentration of eluent as well as the interaction of pH value of buffer and salt concentration of eluent showed significant influence on the HCP content in the harvest.The optimal sample load,flow rate as well as pH value and salt concentration of eluent were 15 mg/mL,120 cm/h,7.0 ～ 8.0 and 0.1 mol/L respectively.The HCP contents in eluents under the optimal condition were less than 400 ng/mg,which met the requirements for verification within the range of results in determined operating space.ConclusionThe condition for removal of HCP by anion exchange chromatography was successfully optimized by DOE,which provided a reference for further application of DOE in the biopharmaceutical field.

Optimization of glycosylation type of recombinant human growth hormone-Fc fusion protein expressed in CHO cells / 中国生物制品学杂志

@#Objective To optimize the expression of recombinant human growth hormone-Fc(rhGH-Fc)fusion protein in CHO cells in order to obtain better glycosylation ratio and lower content of highmannose.Methods CHO cells expressing rhGH-Fc were cultured in a 7 L bioreactor.The glycosylation modifications of rhGH-Fc were adjusted by improving the composition of feeding media(using three commercial media:Gly-1:EX-CELL Glycosylation Adjust,Gly-2:SHEFF-CHO PLUS PG ACF and Gly-3:EfficientFeed C + AGT Supplement & GlycanTune C + Total Feed),and the glycosylation type and proportion of the target proteins were analyzed by mass spectrometry.Results The G0F(main glycosylation types:G0,G1 and G2;F:fucose)of Gly-1,Gly-2 and Gly-3 were 32.89%,58.66% and 33.28%,the G1F were 31.39%,18.03%and 34.90%,and the G2F were 31.39%,18.03% and 34.90%,respectively.Gly-1 and Gly-3 made the target protein contain less G0F while more G2F;Gly-3 feeding scheme-showed less high mannose modification than the other two schemes.Conclusion Gly-1 medium changed the glycosylation modification from G0F to G1F and G2F,while Gly-2 medium changed that from G2F and G1F to G0F.However,Gly-3 medium changed the glycosylation modification from G0F to G1F and G2F,and the contentof high mannose was less than 5%,which may have a better effect on modifying glycosylation type and proportion of the target protein.

Procine recombinant NK-lysin inhibits hepatocellular carcinoma metastasis by downregulating FKBP3 and inhibiting oxidative phosphorylation and glycolysis: a proteomic analysis / 南方医科大学学报

OBJECTIVE@#To investigate the potential mechanisms that mediate the inhibitory effect of porcine recombinant NKlysin (prNK-lysin) against liver cancer cell metastasis.@*METHODS@#HPLC-tandem mass spectrometry was used to identify the differentially expressed proteins in prNK-lysin-treated hepatocellular carcinoma SMMOL/LC-7721 cells in comparison with the control and PBS-treated cells. GO functional annotation and KEGG pathway analysis of the differentially expressed proteins were performed using GO and KEGG databases. RT-qPCR was used to determine the mRNA expression levels of polypeptide-N-acetylgalactosaminotransferase 13 (GALNT13), transmembrane protein 51 (TMEM51) and FKBP prolyl isomerase 3 (FKBP3) in the cells, and the protein expression of FKBP3 was verified using Western blotting.@*RESULTS@#Proteomic analysis identified 1989 differentially expressed proteins in prNK-lysin-treated cells compared with the control cells, and 2753 compared with PBS-treated cells. Fifteen proteins were differentially expressed between PBS-treated and the control cells, and 1909 were differentially expressed in prNK- lysin group compared with both PBS and control groups. These differentially expressed proteins were involved mainly in the viral process, translational initiation and RNA binding and were enriched mainly in ribosome, protein process in endoplasmic reticulum, and RNA transport pathways. RT-qPCR showed that compared with the control group, prNK-lysin treatment significantly increased the mRNA expressions of GALNT13 (P < 0.05) and TMEM51 (P < 0.01) and lowered FKBP3 mRNA expression (P < 0.05). Western blotting also showed a significantly decreased expression of FKBP3 protein in prNK-lysin-treated cells (P < 0.001).@*CONCLUSION@#Treatment with prNK-lysin causes significant changes in protein expression profile of SMMOL/LC-7721 cells and inhibits hepatocellular carcinoma metastasis by downregulating FKBP3 protein and affecting the cellular oxidative phosphorylation and glycolysis pathways.

Effect of Recombinant Human Thrombopoietin (rhTPO) on Long-term Hematopoietic Recovery in Mice with Acute Radiation Sickness and Relative Mechanism / 中国实验血液学杂志

OBJECTIVE@#To investigate the effect and relative mechanism of Recombinant Human Thrombopoietin (rhTPO) on long-term hematopoietic recovery in mice with acute radiation sickness.@*METHODS@#Mice were intramuscularly injected with rhTPO (100 μg/kg) 2 hours after total body irradiation with 60Co γ-rays (6.5 Gy). Moreover, six months after irradiation, peripheral blood, hematopoietic stem cells (HSC) ratio, competitive transplantation survival rate and chimerization rate, senescence rate of c-kit+ HSC, and p16 and p38 mRNA expression of c-kit+ HSC were detected.@*RESULTS@#Six months after 6.5 Gy γ-ray irradiation, there were no differences in peripheral blood white blood cells, red blood cells, platelets, neutrophils and bone marrow nucleated cells in normal group, irradiated group and rhTPO group (P>0.05). The proportion of hematopoietic stem cells and multipotent progenitor cells in mice of irradiated group was significantly decreased after irradiation (P<0.05), but there was no significant changes in rhTPO group (P>0.05). The counts of CFU-MK and BFU-E in irradiated group were significantly lower than that in normal group, and rhTPO group was higher than that of the irradiated group(P<0.05). The 70 day survival rate of recipient mice in normal group and rhTPO group was 100%, and all mice died in irradiation group. The senescence positive rates of c-kit+ HSC in normal group, irradiation group and rhTPO group were 6.11%, 9.54% and 6.01%, respectively (P<0.01). Compared with the normal group, the p16 and p38 mRNA expression of c-kit+ HSC in the irradiated mice were significantly increased (P<0.01), and it was markedly decreased after rhTPO administration (P<0.01).@*CONCLUSION@#The hematopoietic function of mice is still decreased 6 months after 6.5 Gy γ-ray irradiation, suggesting that there may be long-term damage. High-dose administration of rhTPO in the treatment of acute radiation sickness can reduce the senescence of HSC through p38-p16 pathway and improve the long-term damage of hematopoietic function in mice with acute radiation sickness.

Towards better antivenoms: navigating the road to new types of snakebite envenoming therapies

Abstract Snakebite envenoming is a significant global health challenge, and for over a century, traditional plasma-derived antivenoms from hyperimmunized animals have been the primary treatment against this infliction. However, these antivenoms have several inherent limitations, including the risk of causing adverse reactions when administered to patients, batch-to-batch variation, and high production costs. To address these issues and improve treatment outcomes, the development of new types of antivenoms is crucial. During this development, key aspects such as improved clinical efficacy, enhanced safety profiles, and greater affordability should be in focus. To achieve these goals, modern biotechnological methods can be applied to the discovery and development of therapeutic agents that can neutralize medically important toxins from multiple snake species. This review highlights some of these agents, including monoclonal antibodies, nanobodies, and selected small molecules, that can achieve broad toxin neutralization, have favorable safety profiles, and can be produced on a large scale with standardized manufacturing processes. Considering the inherent strengths and limitations related to the pharmacokinetics of these different agents, a combination of them might be beneficial in the development of new types of antivenom products with improved therapeutic properties. While the implementation of new therapies requires time, it is foreseeable that the application of biotechnological advancements represents a promising trajectory toward the development of improved therapies for snakebite envenoming. As research and development continue to advance, these new products could emerge as the mainstay treatment in the future.