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1.
Chinese Journal of Biotechnology ; (12): 4277-4292, 2021.
Article in Chinese | WPRIM | ID: wpr-921505

ABSTRACT

The influence of different affinity tags on enzyme characteristics varies. The (S)-carbonyl reductase 2 (SCR2) from Candida parapsilosis can reduce 2-hydroxyacetophenone, which is a valuable prochiral ketones. Different affinity tags, i.e. his-tag, strep-tag and MBP-tag, were attached to the N terminus of SCR2. These tagged SCR2 enzymes, i.e. his6-SCR2, strep-SCR2 and MBP-SCR2, were heterologously expressed in Escherichia coli and purified to study their characteristics towards 2-hydroxyacetophenone reduction. Affinity tags did affect the characteristics of the recombinant SCR2 enzymes. Specifically, affinity tags affect the stability of recombinant SCR2 enzymes: 1) At pH 6.0, the remaining enzyme activities of his6-SCR2 and strep-SCR2 were only 95.2% and 90.0% of the untagged SCR2, while that of MBP-SCR2 was 1.2 times of the untagged SCR2 after incubating for 13 h at 30 °C. 2) The half-life of MBP-SCR2 at 50 °C was 26.6%-48.8% longer than those of strep-SCR2, his6-SCR2 and untagged SCR2. 3) The kcat of MBP-SCR2 was about 1.25-1.45 times of that of small affinity-tagged and untagged SCR2 after storing at -80 °C for 60 d. Structural informatics indicated that the α-helices at the C terminus of MBP-SCR2 contributed to the stability of the N terminus of fusion protein of SCR2. Data from circular dichroism showed that the MBP-tag has some influence on the secondary structure of SCR2, while melting temperature analysis demonstrated that the Tm of the recombinant MBP-SCR2 was about 5 °C higher than that of the untagged SCR2. This study obtained an efficient and stable recombinant SCR2, i.e. the MBP-SCR2. Moreover, this study could serve as a reference for other researchers to evaluate and select appropriate affinity tags for their research.


Subject(s)
Alcohol Oxidoreductases , Escherichia coli/genetics , Recombinant Fusion Proteins/genetics
2.
Chinese Journal of Biotechnology ; (12): 2915-2923, 2021.
Article in Chinese | WPRIM | ID: wpr-887853

ABSTRACT

Antimicrobial peptides are the most promising alternatives to antibiotics. However, the strategy of producing antimicrobial peptides by recombinant technology is complicated and expensive, which is not conducive to the large-scale production. Oxysterlin 1 is a novel type of cecropin antimicrobial peptide mainly targeting on Gram-negative bacteria and is of low cytotoxicity. In this study, a simple and cost-effective method was developed to produce Oxysterlin 1 in Escherichia coli. The Oxysterlin 1 gene was cloned into a plasmid containing elastin-like polypeptide (ELP) and protein splicing elements (intein) to construct the recombinant expression plasmid (pET-ELP-I-Oxysterlin 1). The recombinant protein was mainly expressed in soluble form in E. coli, and then the target peptide can be purified with a simple salting out method followed by pH changing. The final yield of Oxysterlin 1 was about 1.2 mg/L, and the subsequent antimicrobial experiment showed the expected antimicrobial activity. This study holds promise for large-scale production of antimicrobial peptides and the in-depth study of its antimicrobial mechanism.


Subject(s)
Elastin , Escherichia coli/genetics , Inteins , Peptides/pharmacology , Pore Forming Cytotoxic Proteins , Recombinant Fusion Proteins/genetics
3.
Chinese Medical Journal ; (24): 1967-1976, 2021.
Article in English | WPRIM | ID: wpr-887626

ABSTRACT

BACKGROUND@#Innovative coronavirus disease 2019 (COVID-19) vaccines, with elevated global manufacturing capacity, enhanced safety and efficacy, simplified dosing regimens, and distribution that is less cold chain-dependent, are still global imperatives for tackling the ongoing pandemic. A previous phase I trial indicated that the recombinant COVID-19 vaccine (V-01), which contains a fusion protein (IFN-PADRE-RBD-Fc dimer) as its antigen, is safe and well tolerated, capable of inducing rapid and robust immune responses, and warranted further testing in additional clinical trials. Herein, we aimed to assess the immunogenicity and safety of V-01, providing rationales of appropriate dose regimen for further efficacy study.@*METHODS@#A randomized, double-blind, placebo-controlled phase II clinical trial was initiated at the Gaozhou Municipal Centre for Disease Control and Prevention (Guangdong, China) in March 2021. Both younger (n = 440; 18-59 years of age) and older (n = 440; ≥60 years of age) adult participants in this trial were sequentially recruited into two distinct groups: two-dose regimen group in which participants were randomized either to follow a 10 or 25 μg of V-01 or placebo given intramuscularly 21 days apart (allocation ratio, 3:3:1, n = 120, 120, 40 for each regimen, respectively), or one-dose regimen groups in which participants were randomized either to receive a single injection of 50 μg of V-01 or placebo (allocation ratio, 3:1, n = 120, 40, respectively). The primary immunogenicity endpoints were the geometric mean titers of neutralizing antibodies against live severe acute respiratory syndrome coronavirus 2, and specific binding antibodies to the receptor binding domain (RBD). The primary safety endpoint evaluation was the frequencies and percentages of overall adverse events (AEs) within 30 days after full immunization.@*RESULTS@#V-01 provoked substantial immune responses in the two-dose group, achieving encouragingly high titers of neutralizing antibody and anti-RBD immunoglobulin, which peaked at day 35 (161.9 [95% confidence interval [CI]: 133.3-196.7] and 149.3 [95%CI: 123.9-179.9] in 10 and 25 μg V-01 group of younger adults, respectively; 111.6 [95%CI: 89.6-139.1] and 111.1 [95%CI: 89.2-138.4] in 10 and 25 μg V-01 group of older adults, respectively), and remained high at day 49 after a day-21 second dose; these levels significantly exceed those in convalescent serum from symptomatic COVID-19 patients (53.6, 95%CI: 31.3-91.7). Our preliminary data show that V-01 is safe and well tolerated, with reactogenicity predominantly being absent or mild in severity and only one vaccine-related grade 3 or worse AE being observed within 30 days. The older adult participants demonstrated a more favorable safety profile compared with those in the younger adult group: with AEs percentages of 19.2%, 25.8%, 17.5% in older adults vs. 34.2%, 23.3%, 26.7% in younger adults at the 10, 25 μg V-01 two-dose group, and 50 μg V-01 one-dose group, respectively.@*CONCLUSIONS@#The vaccine candidate V-01 appears to be safe and immunogenic. The preliminary findings support the advancement of the two-dose, 10 μg V-01 regimen to a phase III trial for a large-scale population-based evaluation of safety and efficacy.@*TRIAL REGISTRATION@#http://www.chictr.org.cn/index.aspx (No. ChiCTR2100045107, http://www.chictr.org.cn/showproj.aspx?proj=124702).


Subject(s)
Aged , Antibodies, Viral , COVID-19/therapy , COVID-19 Vaccines , Double-Blind Method , Humans , Immunization, Passive , Recombinant Fusion Proteins , SARS-CoV-2
4.
Arq. bras. oftalmol ; 83(6): 517-525, Nov.-Dec. 2020. tab
Article in English | LILACS | ID: biblio-1153088

ABSTRACT

ABSTRACT Purpose: To evaluate vascular density in super­ficial and deep capillary plexuses of the retina, measured using optical coherence tomography angiography in patients with branch retinal vein occlusion. Affected eyes were compared with the contralateral eye of the same patient and both were compared with normal eyes. Methods: A cross-sectional study including 16 previously untreated patients with branch retinal vein occlusion. Patients with poor quality examinations, bilateral disease, high refractive error, or any other retinal or choroidal disease were excluded. A total of 31 patients without eye disease were also selected as a comparison group. All participants underwent five optical coherence tomography angiographies, and only those with at least two good quality examinations were selected. The Kruskal-Wallis, Wilcoxon signed-rank, and Mann-Whitney U tests were used for the statistical analysis. Results: Vascular density was lower in affected eyes compared with contralateral eyes: whole density (p=0.020 for capillary plexuses superficial; p=0.049 for deep capillary plexuses) and parafoveal density (p=0.020 for capillary plexuses superficial; p=0.011 for deep capillary plexuses). Vascular density was also lower in affected eyes compared with normal eyes: whole density (p<0.001 for capillary plexuses superficial and deep) and parafoveal density (p<0.001 for capillary plexuses superficial and deep). Whole density (p=0.001 for capillary plexuses superficial and deep) and parafoveal density (p=0.001 for capillary plexuses superficial; p<0.001 for deep capillary plexuses) were both lower in the contralateral eyes compared with normal eyes. Following adjustment for arterial hypertension, this difference was no longer observed. Conclusions: Vascular density in capillary plexuses and deep capillary plexuses was lower in the eyes affected by branch retinal vein occlusion. Furthermore, the lower vascular density noted in the contralateral eyes indicates that changes most likely occurred in these eyes prior to the appearance of any clinically detectable alterations, reflecting the early signs of hypertensive retinopathy.


RESUMO Objetivo: Avaliar a densidade vascular do plexo capilar superficial e profundo da retina, usando angiografia por tomografia de coerência óptica em pacientes com oclusão de ramo da veia central da retina, comparando o olho afetado com o contralateral do mesmo paciente e ambos com olhos normais. Métodos: Estudo transversal. Incluídos dezesseis pacientes com oclusão de ramo da veia central da retina sem tratamento prévio. Pacientes com exames de baixa qualidade, altas ametropias, outras patologias de retina ou coróide foram excluídos. Para comparação, trinta e um pacientes sem doença ocular foram selecionados. Todos foram submetidos a cinco exames angiografia por tomografia de coerência óptica, apenas aqueles com pelo menos dois exames de boa qualidade permaneceram no estudo. Os testes Kruskal-Wallis, Wilcoxon, e Mann-Whitney foram utilizados. Resultados: Densidades vasculares mais baixas do plexo capilar superficial e plexo capilar profundo foram observadas quando olhos com oclusão de ramo da veia central da retina foram comparados com os contralaterais: densidade total (p=0,02 para plexo capilar superficial, p=0,049 para plexo capilar profundo), densidade parafoveal (p=0,02 para plexo capilar superficial, p=0,011 para plexo capilar profundo). Comparando olhos acometidos com olhos normais, também foram observadas densidades vasculares mais baixas de plexo capilar superficial e plexo capilar profundo: densidade total (ambos com p<0,001) e densidade parafoveal (ambos com p<0,001). Quando os olhos contralaterais foram comparados aos normais, tanto a densidade total do plexo capilar superficial e plexo capilar profundo (ambos com p=0,001) quanto a densidade parafoveal (plexo capilar superficial com p=0,001, plexo capilar profundo com p<0,001) foram menores. Ao se realizar uma subanálise, minimizando o fator hipertensão arterial, esta diferença não se manteve. Conclusões: Densidades vasculares mais baixas do plexo capilar superficial e do plexo capilar profundo foram observadas em olhos com oclusão de ramo da veia central da retina. Além disso, a presença de densidades vasculares mais baixas nos olhos contralaterais mostra que já existem altera­ções nesses olhos antes das alterações clínicas, devido a al­terações inicias da retinopatia hipertensiva.


Subject(s)
Humans , Male , Female , Middle Aged , Retinal Vessels/diagnostic imaging , Recombinant Fusion Proteins/administration & dosage , Retinal Vein Occlusion/diagnosis , Capillaries/diagnostic imaging , Fluorescein Angiography/methods , Visual Acuity , Choroid/diagnostic imaging , Tomography, Optical Coherence/methods , Retinal Vein Occlusion/physiopathology , Retinal Vein Occlusion/drug therapy , Retrospective Studies , Follow-Up Studies , Treatment Outcome , Fundus Oculi , Microcirculation/drug effects
5.
Arq. bras. oftalmol ; 83(6): 552-561, Nov.-Dec. 2020.
Article in English | LILACS | ID: biblio-1153080

ABSTRACT

ABSTRACT Age-related macular degeneration is the leading cause of vision loss in elderly individuals, as well as a medical and socio-economic challenge. The treatment of dry age-related macular degeneration is based on vitamin supplementation. New treatment studies are focused on preventing the progression of degeneration and repopulating the atrophic macula. Recently, research on the treatment of neovascular age-related macular degeneration experienced a breakthrough with the advent of anti-vascular endothelial growth factor inhibitors. Nevertheless, despite the fact that ranibizumab, aflibercept, and bevacizumab are effective in reducing severe visual impairment, patients usually lose some vision over time. Therefore, the search for new therapies and diagnostic methods is fundamentally important. Current studies are focused on new anti-vascular endothelial growth factor drugs, nucleoside reverse transcriptase inhibitors, antibody against sphingosine-1-phosphate, anti-platelet-derived growth factor, gene therapy, and RNA interference. The results of ongoing clinical studies may improve the therapy of age-related macular degeneration.


RESUMO Degeneração macular relacionada à idade (DMRI) é a principal causa de perda de visão em pessoas idosas. É também um desafio médico e socioeconômico. O tratamento da degeneração macular relacionada à idade seca baseia-se na suplementação vitamínica. Novos tratamentos estão focados na prevenção da progressão da degeneração e tentativas de repovoar a mácula atrófica. A degeneração macular relacionada à idade neovascular experimentou um grande avanço com o advento dos inibidores do fator de crescimento endotelial anti-vascular (anti-VEGF); no entanto, apesar do ranibizumab, aflibercept e bevacizumab serem eficazes na redução do comprometimento visual grave, os pacientes geralmente per­dem visão ao longo do tempo. Portanto, a busca por novas terapias, tratamentos e diagnósticos é de fundamental importância. Os estudos estão focados em novos fármacos sobre fator de crescimento endotelial anti-vascular, inibidores nucleosideos da transcriptase reversa, anticorpos contra esfingosina-1-fosfato, fator de crescimento derivado de plaquetas, terapia genética e RNA de interferência. A terapia para degeneração macular relacionada à idade está prestes a melhorar como resultado desses estudos clínicos em andamento.


Subject(s)
Humans , Aged , Angiogenesis Inhibitors , Macular Degeneration , Recombinant Fusion Proteins/therapeutic use , Visual Acuity , Angiogenesis Inhibitors/therapeutic use , Receptors, Vascular Endothelial Growth Factor/therapeutic use , Vascular Endothelial Growth Factor A , Intravitreal Injections , Bevacizumab/therapeutic use , Ranibizumab/therapeutic use , Macular Degeneration/drug therapy
6.
Arch. endocrinol. metab. (Online) ; 64(5): 623-629, Sept.-Oct. 2020. tab, graf
Article in English | LILACS | ID: biblio-1131137

ABSTRACT

SUMMARY Hypophosphatasia (HPP) is a rare disease with a high mortality rate in its severe forms. It is caused by mutations within the gene encoding the tissue-nonspecific alkaline phosphatase (TNSALP), an enzyme responsible for bone mineralization. In 2015, the Food and Drug Administration approved the use of asfotase alfa, the first medication showing benefit in the treatment of HPP. We describe a case with a 2-year follow-up of the first Brazilian child treated with asfotase alfa. A 5-year-old boy, born to consanguineous parents, was diagnosed with HPP at the age of 20 months. During prenatal ultrasonography, polyhydramnios and shortening of long bones were detected. After birth, he presented delayed motor development, repeated respiratory infections, and bone deformities. At the age of 2 years and 8 months, he started walking and had already lost his primary teeth. He had reduced levels of alkaline phosphatase (ALP), elevated levels of pyridoxal 5'-phosphate (PLP), and a p.Ala33Val (c.98C>T) missense mutation in homozygosis in the TNSALP gene. His parents and sister also had reduced ALP levels, high PLP levels, and the same mutation in heterozygosis. His father and sister were healthy, and his mother was diagnosed with rickets in childhood, which resulted in short physical stature and lower limb deformities. The patient was started on asfotase alfa at the age of 2 years and 10 months. After 2 years of treatment, he improved his motor skills, had no further episodes of severe respiratory infection, and showed improved radiological findings of rickets, without any severe side effect.


Subject(s)
Humans , Male , Infant, Newborn , Child, Preschool , Child , Alkaline Phosphatase , Hypophosphatasia/genetics , Hypophosphatasia/drug therapy , Hypophosphatasia/diagnostic imaging , United States , Recombinant Fusion Proteins , Brazil , Immunoglobulin G , Follow-Up Studies , Enzyme Replacement Therapy
7.
Arq. bras. oftalmol ; 83(5): 396-401, Sept.-Oct. 2020. tab, graf
Article in English | LILACS | ID: biblio-1131628

ABSTRACT

ABSTRACT Purpose: To compare the efficacy of three initial monthly intravitreal aflibercept injections followed by pro re nata (3+PRN) dosing versus five initial monthly intravitreal aflibercept injections followed by pro re nata (5+PRN) dosing in patients with diabetic macular edema. Methods: A total of 60 treatment-naïve patients with macular edema who underwent intravitreal aflibercept injections (2 mg/0.05 mL) with at least one year of follow-up were analyzed in this retrospective and comparative study. The patients were divided into two groups according to the number of intravitreal aflibercept injections administered in the loading phase. The 3+PRN group comprised 27 patients, whereas the 5+PRN group comprised 33 patients. The visual and anatomical outcomes were compared between the two groups at baseline and at 3, 6, 9, and 12 months. Results: Both 3+PRN and 5+PRN, showed statistically significant improvements in the best-corrected visual acuity and central macular thicknesse throughout the study period (p<0.001 and, p<0.001, respectively). There were no significant differences between the two groups in terms of changes in the best-corrected visual acuity and central macular thickness (p=0.453 and, p=0.784, respectively). The mean number of intravitreal aflibercept injections was significantly greater in the 5+PRN group (6.1 ± 0.8) than in the 3+PRN group (3.9 ± 0.8) (p<0.001). Conclusion: The 3+PRN and 5+PRN regimens showed similar 12-month visual and anatomical outcomes following treatment with intravitreal aflibercept injections in patients with macular edema.


RESUMO Objetivo: Comparar a eficácia de três injeções intravítreas mensais iniciais de aflibercept, seguidas de dosagem de pro re nata (3+PRN) versus cinco injeções mensais iniciais intravítreas de aflibercept, seguidas de doses de pro re nata (5 + PRN) em pacientes com edema macular diabético. Métodos: Foram analisados neste estudo retrospectivo e comparativo 60 pacientes que não receberam tratamento prévio com edema macular e foram submetidos a injeções intravítreas de aflibercept (2 mg/0,05 mL) com pelo menos um ano de acompanhamento. Os pacientes foram divididos em dois grupos de acordo com o número de injeções intravítreas de aflibercept administradas na fase inicial. O grupo 3+PRN compreendeu 27 pacientes, enquanto o grupo 5+PRN compreendeu 33 pacientes. Os resultados visuais e anatômicos foram comparados entre os dois grupos no período inicial e aos 3, 6, 9 e 12 meses. Resultados: Tanto os grupos 3+PRN quanto 5+PRN mostraram melhoras estatisticamente significativas na acuidade visual melhor corrigida e na espessura macular central ao longo do período de estudo (p<0,001 e p <0,001, respectivamente). Não houve diferenças significativas entre os dois grupos em termos de alterações na acuidade visual melhor corrigida e na espessura macular central (p=0,453 e p=0,784, respectivamente). O número médio de injeções intravítreas de aflibercept foi significativamente maior no grupo 5+PRN (6,1 ± 0,8) do que no grupo 3+PRN (3,9 ± 0,8) (p <0,001). Conclusão: Os regimes 3+PRN e 5+PRN mostraram resultados visuais e anatômicos semelhantes em 12 meses após o tratamento com injeções intravítreas de aflibercept em pacientes com edema macular.


Subject(s)
Humans , Recombinant Fusion Proteins , Macular Edema , Angiogenesis Inhibitors , Receptors, Vascular Endothelial Growth Factor , Diabetes Mellitus , Diabetic Retinopathy , Recombinant Fusion Proteins/administration & dosage , Visual Acuity , Macular Edema/drug therapy , Retrospective Studies , Treatment Outcome , Angiogenesis Inhibitors/administration & dosage , Receptors, Vascular Endothelial Growth Factor/administration & dosage , Diabetic Retinopathy/complications , Diabetic Retinopathy/drug therapy , Intravitreal Injections , Ranibizumab/therapeutic use
8.
Arq. bras. oftalmol ; 83(3): 175-179, May-June 2020. tab
Article in English | LILACS | ID: biblio-1131590

ABSTRACT

ABSTRACT Purpose: This survey aimed at assessing the clinical characteristics of patients with inflammatory reactions after intravitreal injection of antiangiogenic agents and the techniques employed by Brazilian retina specialists. Methods: We sent an 18-item questionnaire electronically to retina specialists who are using antiangiogenic agents. We got the responses between September 21 and December 23, 2018. Results: A total of 58 retina specialists participated. Most of them were from Southeastern Brazil (50%), 82.8% were dedicated to both medical and surgical practices, and 86.2% had practiced for more than 5 years. Respondents reported a mean number of 2.14 ± 1.63 patients with inflammation, 44.8% with panuveitis, and 79.3% with onset of symptoms within 72 h. Specialists used aflibercept (53.4%), bevacizumab (29.3%), and ranibizumab (27.6%). Most patients were treated with steroid drops (70.7%), and their inflammation subsided after 11.5 ± 11.5 days (86.2% lacked irreversible complications). The specialists blamed the syringe as the cause of the inflammation in 25.9% of the cases, 41.4% used Becton-Dickinson Ultra-Fine syringes, 43.1% injected the drug at room temperature, and 37.9% removed the air (53.4% by flicking the syringe). Most specialists did not detect silicone oil (67.2%), but 17.2% of them performed vitrectomies to remove vitreous opacities. Finally, 44.8% of specialists injected the same antiangiogenic agent in an eye with prior inflammatory reaction without further inflammation. Conclusions: Most specialists reported cases of early-onset inflammation after intravitreal injection of antiangiogenic agents. The incidence of irreversible complications was low. Aflibercept was the most common agent used. The causes of inflammation remain unknown, but we formulated some relevant hypotheses.


RESUMO Objetivo: Esta pesquisa teve como objetivo avaliar as características clínicas de pacientes com reações inflamatórias após injeção intravítrea de agentes antiangiogênicos e as técnicas empregadas por especialistas em retina brasileiros. Métodos: Enviamos eletronicamente um questionário de 18 itens para especialistas em retina que usam agentes antiangiogênicos. Recebemos as respostas entre 21 de setembro e 23 de dezembro de 2018. Resultados: Um total de 58 especialistas em retina participaram. A maioria era do Sudeste do Brasil (50%), 82,8% eram dedicados a práticas médicas e cirúrgicas e 86,2% praticavam há mais de 5 anos. Os entrevistados informaram um número médio de 2,14 ± 1,63 pacientes com inflamação, 44,8% com panuveíte e 79,3% com início dos sintomas dentro de 72 horas. Especialistas utilizaram aflibercepte (53,4%), bevacizumabe (29,3%) e ranibizumabe (26=7,6%). A maioria dos pacientes foi tratada com colírios de esteroides (70,7%), e sua inflamação diminuiu após 11,5 ± 11,5 dias (86,2% não apresentaram complicações irreversíveis). Os especialistas responsabilizaram a seringa como causa da inflamação em 25,9% dos casos, 41,4% usaram seringas Becton-Dickinson Ultra-Fine, 43,1% injetaram a droga em temperatura ambiente e 37,9% removeram o ar (53,4% sacudindo a seringa). A maioria dos especialistas não detectou óleo de silicone (67,2%), mas 17,2% realizaram vitrectomias para remoção de opacidades vítreas. Finalmente, 44,8% dos especialistas injetaram o mesmo agente angiogênicos em um olho com reação inflamatória prévia, sem surgimento de nova inflamação. Conclusões: A maioria dos especialistas relatou casos de inflamação de início precoce após injeção intravítrea de agentes antiangiogênicos. A incidência complicações irreversíveis foi baixa. Aflibercepte foi o agente mais frequentemente usado. As causas da inflamação permanecem desconhecidas, embora formulamos algumas hipóteses relevantes.


Subject(s)
Humans , Specialization , Angiogenesis Inhibitors/therapeutic use , Bevacizumab , Retina , Recombinant Fusion Proteins , Brazil , Surveys and Questionnaires , Receptors, Vascular Endothelial Growth Factor , Intravitreal Injections , Ranibizumab , Inflammation
9.
Chinese Journal of Biotechnology ; (12): 1223-1231, 2020.
Article in Chinese | WPRIM | ID: wpr-826855

ABSTRACT

In order to prepare human-mouse chimeric cytomegalovirus-immunoglobulin M (CMV-IgM) in vitro and study the effects of different signal peptides on the secretion of CMV-IgM, genes were amplified from hybridoma cell line using RLM-RACE to construct the expression vector of chimeric CMV-IgM. Then, the signal peptide of SigF itself was replaced by five different secreted signal peptides (SigA-SigE) by PCR method, and the CHO cell was chosen as host cell for in vitro expression. SDS-PAGE, SEC-HPLC and ELISA experiments were carried out to evaluate the protein expression level and immunoreactivity of the purified CMV-IgM. A 910 kDa recombinant protein was successfully prepared and signal peptides (SigA-SigE) had an increased expressed CMV-IgM, which were 6.72, 5.19, 1.44, 1.85 and 1.98 times higher than that of the CMV 6# cell signal peptide SigF. In summary, this work provides a theoretical basis for the development of human-mouse chimeric CMV-IgM, and a novel route to increase the expression level of CMV-IgM.


Subject(s)
Animals , Antibodies, Viral , Genetics , Allergy and Immunology , Cricetinae , Cytomegalovirus , Allergy and Immunology , Enzyme-Linked Immunosorbent Assay , Gene Expression , Humans , Immunoglobulin M , Allergy and Immunology , Mice , Protein Sorting Signals , Recombinant Fusion Proteins , Allergy and Immunology
10.
Chinese Journal of Biotechnology ; (12): 2868-2876, 2020.
Article in Chinese | WPRIM | ID: wpr-878536

ABSTRACT

Tissue inhibitor of metalloproteinases-2 (TIMP-2) inhibits tumor migration and invasion. Obtaining TIMP-2 protein is conducive to a comprehensive and in-depth study of its function and mechanism in tumorigenesis and development. We collected human TIMP-2 protein through prokaryotic expression in vitro. We expressed, purified and characterized human TIMP-2 protein. First, the human TIMP-2 gene was cloned from the cDNA obtained by reverse transcription of total RNA of human lung cancer A549 cells, and constructed to pET28a vector. The recombinant plasmid pET28a-TIMP-2 was transformed into Escherichia coli BL21(DE3) after restriction endonuclease digestion and sequencing analysis. The expression of TIMP-2 protein was induced by isopropyl-β-D-thiogalactoside (IPTG), and the expression conditions were optimized. After purification by nickel affinity column, the fusion protein His-TIMP-2 was identified by Western blotting method and its biological activity was detected by gelatin zymography. The fusion protein His-TIMP-2 existed in the form of inclusion body in E. coli. In a certain range, the concentration of IPTG had no significant effect on the expression amount of His-TIMP-2. But in this expression system, induction temperature and time were the key parameters, and the expression amount of His-TIMP-2 in E. coli increased with the increase of induction temperature. The purified and refolded fusion protein could effectively inhibit the activity of matrix metalloproteinases expressed by human lung cancer A549 cells. The acquisition of active fusion protein lays a foundation for further study of the function and mechanism of human TIMP-2, and is of great significance for tumor therapy.


Subject(s)
Cloning, Molecular , Escherichia coli/genetics , Humans , Recombinant Fusion Proteins/genetics , Recombinant Proteins , Tissue Inhibitor of Metalloproteinase-2/genetics
11.
Article in Chinese | WPRIM | ID: wpr-828878

ABSTRACT

OBJECTIVE@#To prepare the recombinant peptide MVF-HER3 I composed of the 183-227aa peptide segment of human epidermal growth factor receptor 3 (HER3 I) and the measles virus protein 288-302 peptide segment (MVF), and prepare polyclonal antibodies (PcAb) against this recombinant peptide.@*METHODS@#The MVF-HER3 I gene was synthesized chemically and subcloned into pET21b or pET32a plasmid containing Thioredoxin (Trx) tag gene. The recombinant plasmids were identified by endonuclease digestion. MVF-HER3 I was expressed in BL21(DE3) cells under an optimal bacterial expression condition. The fusion protein Trx-MVF-HER3 I was purified using nickel ion affinity chromatography, and the purified protein was digested by enterokinase to remove Trx tag. The digested mixture underwent further nickel ion affinity chromatography to obtain purified MVF-HER3 I. The purified MVF-HER3 I was used to immunize SD rats subcutaneously for preparing anti-MVF-HER3 I PcAb. The titer of PcAb was determined using ELISA. The bindings of anti-MVF-HER3 I PcAb to MVF-HER3 I, native HER3 and MCF7 cells were analyzed using immunoblotting, immunoprecipitation and laser confocal microscopy. The growth inhibition effect of the antibodies on MCF7 cells cultured in the absence or presence of NRG was assessed using sulforhodamine B.@*RESULTS@#The recombinant peptide gene could not be expressed alone, but could be efficiently expressed after fusion with Trx gene under optimized conditions. The fusion peptide MVF-HER3 I was successfully prepared from Trx-MVF-HER3 I. The anti-MVF-HER3 I PcAb, with a titer reaching 1: 512 000, specifically bound to MVF-HER3 I, recognized native HER3 and bound to the membrane of MCF7 cells. The obtained PcAb could dose-dependently inhibit the growth of MCF7 cells irrespective of the presence or absence of NRG.@*CONCLUSIONS@#We successfully obtained the recombinant peptide MVF-HER3 I and prepared its PcAb, which can facilitate further functional analysis of HER3 signaling pathway.


Subject(s)
Animals , Antibodies , Enzyme-Linked Immunosorbent Assay , Escherichia coli , Humans , Plasmids , Rats , Rats, Sprague-Dawley , Receptor, ErbB-3 , Allergy and Immunology , Recombinant Fusion Proteins
12.
Chinese Journal of Biotechnology ; (12): 969-978, 2020.
Article in Chinese | WPRIM | ID: wpr-826879

ABSTRACT

Drugs targeting immune checkpoint are used for cancer treatment, but resistance to single drug may occur. Combination therapy blocking multiple checkpoints simultaneously can improve clinical outcome. Therefore, we designed a recombinant protein rPC to block multiple targets, which consists of extracellular domains of programmed cell death protein 1 (PD-1) and cytotoxic T lymphocyte-associated antigen 4 (CTLA-4). The coding sequence was inserted into expression vector and stably transfected into HEK293 cells. The culture supernatant was collected and rPC was affinity-purified. Real-time quantitative PCR was used to evaluate the expression levels of ligands for PD-1 and CTLA-4 in several human cancer cell lines. The binding of rPC with cancer cells was examined by immunofluorescence cell staining, the influence of rPC on cancer cell growth was assayed by CCK-8. The results showed that rPC could be expressed and secreted by stably transfected HEK293 cells, the purified rPC could bind to lung cancer NCI-H226 cells which have high levels of ligands for PD-1 and CTLA-4, no direct impact on cancer cell growth could be observed by rPC treatment. The recombinant protein rPC can be functionally assayed further for developing novel immunotherapeutic drugs for cancer.


Subject(s)
Animals , CTLA-4 Antigen , Genetics , Cell Proliferation , HEK293 Cells , Humans , Lung Neoplasms , Metabolism , Programmed Cell Death 1 Receptor , Genetics , Protein Binding , Protein Domains , Genetics , Recombinant Fusion Proteins , Genetics , Metabolism
13.
Article in Chinese | WPRIM | ID: wpr-941991

ABSTRACT

OBJECTIVE@#To analyze the subcellular localization of GTPase of immunity-associated protein 2 (GIMAP2) for the further functional study.@*METHODS@#In the study, we first obtained the protein sequences of GTPase of immunity-associated protein 2 (GIMAP2) from National Center for Biotechnology Information (NCBI) database, and then performed a prediction analysis of its transmembrane structure, nuclear localization signal (NLS), nuclear export signal (NES) and subcellular localization through bioinformatics online tools. GIMAP2 gene amplified by PCR was inserted into the expression vector pQCXIP-mCherry-N1 and positive clones were selected by ampicillin resistance. After using methods to extract and purify, the sequenced recombinant plasmid pQCXIP-GIMAP2-mCherry, together with the retroviral packaging plasmids VSVG and Gag/pol, was transferred into HEK293FT cells by liposomes for virus packaging. The virus supernatant was collected 48 h after transfection and directly infected the human breast cancer cell line MDA-MB-436. Immunofluorescence staining was constructed to detect the localization of endogenous and exogenous GIMAP2 in MDA-MB-436 cells. Meanwhile, green fluorescent chemical dyes were used to label mitochondria, endoplasmic reticulum, and lipid droplets in living MDA-MB-436 cells stably expressing the GIMAP2-mCherry fusion protein. Images for the three dye-labeled organelles and GIMAP2-mCherry fusion protein were captured by super-resolution microscope N-SIM.@*RESULTS@#Bioinformatics analysis data showed that GIMAP2 protein composed of 337 amino acids might contain two transmembrane helix (TM) structures at the carboxyl terminus, of which TMs were estimated to contain 40-41 expected amino acids, followed by the residual protein structures toward the cytoplasmic side. NES was located at the 279-281 amino acids of the carboxyl terminus whereas NLS was not found. GIMAP2 might locate in the lumen of the endoplasmic reticulum. Sequencing results indicated that the expression vector pQCXIP-GIMAP2-mCherry was successfully constructed. Fluorescent staining confirmed that GIMAP2-mCherry fusion protein, co-localized well with endogenous GIMAP2, expressed successfully in the endoplasmic reticulum and on the surface of lipid droplets in MDA-MB-436 cells.@*CONCLUSION@#GIMAP2 localizes in the endoplasmic reticulum and on the surface of LDs, suggesting potential involvement of GIMAP2 in lipid metabolism.


Subject(s)
Amino Acid Sequence , Cytoplasm , GTP Phosphohydrolases , Humans , Membrane Proteins , Nuclear Export Signals , Nuclear Localization Signals , Recombinant Fusion Proteins , Transfection
15.
Arq. Asma, Alerg. Imunol ; 3(3): 207-258, jul.set.2019. ilus
Article in Portuguese | LILACS | ID: biblio-1381240

ABSTRACT

O presente guia apresenta revisão extensa sobre imunobiológicos utilizados, liberados e ainda sob estudo, para o tratamento da asma, doenças alérgicas e imunodeficiências. Além das características físico-químicas de alguns desses fármacos, são revisadas as indicações e os resultados de estudos clínicos realizados para avaliar eficácia e segurança. Separados por doença específica, são apresentados os principais agentes disponíveis e aprovados para utilização segundo as normas regulatórias nacionais.


This guide presents an extensive review of immunobiological drugs used, approved and/or under investigation for the treatment of asthma, allergic diseases and immunodeficiencies. In addition to the physicochemical characteristics of some of these drugs, their indications and results of clinical studies evaluating efficacy and safety are reviewed. The main agents available and approved for use in each specific disease according to national regulatory standards are presented.


Subject(s)
Humans , Asthma , Sinusitis , Biological Therapy , Recombinant Fusion Proteins , Dermatitis, Atopic , Angioedemas, Hereditary , Omalizumab , Food Hypersensitivity , Chronic Urticaria , Anaphylaxis , Antibodies, Monoclonal , Safety , Therapeutics , Biological Products , Pharmaceutical Preparations , Disease , Efficacy , Cytokines , Government Regulation , Allergy and Immunology , Immunologic Deficiency Syndromes , Immunotherapy
16.
Cad. Saúde Pública (Online) ; 35(8): e00145518, 2019. tab, graf
Article in Portuguese | LILACS | ID: biblio-1019617

ABSTRACT

Resumo: Os objetivos foram efetuar a análise do impacto orçamentário para a incorporação de segunda linha terapêutica com terapia antiangiogênica de aplicação intravítrea, para tratamento de edema macular diabético, no âmbito do Sistema Único de Saúde (SUS) em Minas Gerais, Brasil, discutindo sua viabilidade à luz do orçamento do estado. A análise do impacto orçamentário com método determinístico, segundo diretriz do Ministério da Saúde. Foram incluídos os pacientes com provável falha ao tratamento de primeira linha, num horizonte temporal de 5 anos para todas as tecnologias avaliadas. Incluíram-se na análise os medicamentos bevacizumabe (uso off-label), ranibizumabe e aflibercepte. As populações foram calculadas tanto por demanda aferida quanto por estimativa epidemiológica. Como análises de sensibilidade efetuaram-se: cenário com difusão de tecnologia mais lenta; cenário com a entrada de bevacizumabe e ranibizumabe biossimilares no mercado; cenário com a desconsideração da inflação no período. O impacto orçamentário incremental, de acordo com as estimativas de demanda aferida e epidemiológica, respectivamente, foi de R$ 69.493.906,95-R$ 473.226.278,78 para bevacizumabe; R$ 349.319.965,60-R$ 2.378.732.103,09 para ranibizumabe e R$543.867.485,47-R$ 3.703.524.490,16 para aflibercepte. Bevacizumabe foi a alternativa financeiramente mais viável em todos os cenários das estimativas e análises de sensibilidade. Estimou-se incremento próximo a 3%, comparando com o orçamento de 2016 (demanda aferida). Avalia-se que a incorporação é viável dentro do SUS em Minas Gerais, mas sujeita às prioridades da gestão. A discrepância de preços entre produtos de eficácia semelhante é intrigante e tema fértil para estudos futuros.


Abstract: The study's objective was to perform budget impact assessment for the incorporation of second-line intravitreal antiangiogenic therapy for diabatic macular edema in the scope of the Brazilian Unified National Health System (SUS) in Minas Gerais state, Brazil, discussing the incorporation's state budget feasibility. The budget impact assessment was performed as a deterministic method according to Ministry of Health guidelines. The study included patients with probable first-line treatment failure in a five-year timeline for all the technologies assessed. The analysis included the drugs bevacizumab (off-label use), ranibizumab, and aflibercept. The populations were calculated both by observed demand and epidemiological estimate. The following sensitivity analyses were performed: a scenario with slower technology diffusion, a scenario with the market entry of biosimilar versions of bevacizumab and ranibizumab, and a scenario disregarding inflation during the period. The incremental budget impacts according to observed and epidemiologically estimated demand, respectively, were BRL 69,493,906.95 to BRL 473,226,278.78 for bevacizumab; BRL 349,319,965.60 to BRL 2,378,732,103.09 for ranibizumab; and BRL 543,867,485.47 to BRL 3,703,524,490.16 for aflibercept. Bevacizumab proved to be the most financially feasible alternative in all the scenarios of estimates and sensitivity analyses. An increment of nearly 3% was estimated, compared to the 2016 budget (observed demand). The study showed that the incorporation is feasible in the SUS, Minas Gerais State, but subject to management priorities. Price discrepancies between products with similar efficacy is intriguing and provides fertile ground for future studies.


Resumen: El objetivo fue efectuar un análisis del impacto presupuestario en la incorporación de una segunda línea terapéutica, con terapia antiangiogénica de aplicación intravítrea, para el tratamiento de edema macular diabético, en el ámbito del Sistema Único de Salud (SUS), en Minas Gerais, Brasil, discutiendo su viabilidad respecto al presupuesto del estado. Se realizó una análisis del impacto presupuestario con un método determinístico, según la directriz del Ministerio de Salud. Se incluyeron pacientes con probable fracaso al tratamiento de primera línea, en un horizonte temporal de 5 años para todas las tecnologías evaluadas. Se incluyeron en el análisis los medicamentos bevacizumab (uso off-label), ranibizumab y aflibercept. Las poblaciones se calcularon tanto por demanda evaluada, como por estimación epidemiológica. A modo de análisis de sensibilidad se planteó un escenario con una difusión de tecnología más lenta, un escenario con la entrada de bevacizumab y ranibizumab biosimilares en el mercado, y un escenario con la desconsideración de la inflación durante el período. El incremento del impacto presupuestario, de acuerdo con las estimativas de demanda evaluada y epidemiológica, respectivamente, fue BRL 69.493.906,95-BRL 473.226.278,78 en el caso del bevacizumab; BRL 349.319.965,60-BRL 2.378.732.103,09 en el de ranibizumab y BRL 543.867.485,47-BRL 3.703.524.490,16 en el aflibercept. El bevacizumab se mostró la alternativa financiera más viable en todos los escenarios de estimaciones y análisis de sensibilidad. Se estimó un incremento cercano al 3%, comparándolo con el presupuesto de 2016 (demanda evaluada). Se considera que la incorporación es viable dentro del SUS en Minas Gerais, pero sujeta a las prioridades de la gestión. La discrepancia de precios entre productos de eficacia semejante es intrigante y un tema fértil para estudios futuros.


Subject(s)
Humans , Macular Edema/economics , Health Care Costs/statistics & numerical data , Angiogenesis Inhibitors/economics , Diabetic Retinopathy/economics , Recombinant Fusion Proteins/economics , Recombinant Fusion Proteins/therapeutic use , Brazil , Macular Edema/drug therapy , Angiogenesis Inhibitors/therapeutic use , Receptors, Vascular Endothelial Growth Factor/therapeutic use , Diabetic Retinopathy/drug therapy , Bevacizumab/economics , Bevacizumab/therapeutic use , Ranibizumab/economics , Ranibizumab/therapeutic use
17.
Einstein (Säo Paulo) ; 17(2): eAO4583, 2019. tab, graf
Article in English | LILACS | ID: biblio-1001910

ABSTRACT

ABSTRACT Objective: To evaluate clinical features and complications in patients with bowel endometriosis submitted to hormonal therapy. Methods: Retrospective study based on data extracted from medical records of 238 women with recto-sigmoid endometriosis treated between May 2010 and May 2016. Results: Over the course of follow-up, 143 (60.1%) women remained in medical treatment while 95 (39.9%) presented with worsening of pain symptoms or intestinal lesion growth (failure of medical treatment group), with surgical resection performed in 54 cases. Women in the Medical Treatment Group were older (40.5±5.1 years versus 37.3±5.8 years; p<0.0001) and had smaller recto sigmoid lesions (2.1±1.9 versus 3.1±2.2; p=0.008) compared to those who had failed to respond to medical treatment. Similar significant reduction in pain scores for dysmenorrhea, chronic pelvic pain, cyclic dyschezia and dysuria was observed in both groups; however greater reduction in pain scores for dyspareunia was noted in the Surgical Group. Subjective improvement in pain symptoms was also similar between groups (100% versus 98.2%; p=0.18). Major complications rates were higher in the Surgical Group (9.2% versus 0.6%; p=0.001). Conclusion: Patients with recto-sigmoid endometriosis who failed to respond to medical treatment were younger and had larger intestinal lesions. Hormonal therapy was equally efficient in improving pain symptoms other than dyspareunia compared to surgery, and was associated with lower complication rates in women with recto-sigmoid endometriosis. Medical treatment should be offered as a first-line therapy for patients with bowel endometriosis. Surgical treatment should be reserved for patients with pain symptoms unresponsive to hormonal therapy, lesion growth or suspected intestinal subocclusion.


RESUMO Objetivo: Avaliar características clínicas e complicações em pacientes com endometriose intestinal submetidos ao tratamento hormonal. Métodos: Dados de prontuários de 238 pacientes com endometriose de retossigmoide tratadas entre maio de 2010 e maio de 2016 foram coletados para este estudo retrospectivo. Resultados: Durante o período de acompanhamento, 143 (60,1%) mulheres mantiveram tratamento clínico, enquanto 95 (39,9%) tiveram piora dos sintomas de dor ou aumento da lesão intestinal (grupo falha de tratamento clínico), sendo 54 submetidas ao tratamento cirúrgico. As mulheres no Grupo Tratamento Clínico eram mais velhas (40,5±5,1 anos versus 37,3±5,8 anos; p<0,0001) e tinham lesões intestinais menores (2,1±1,9 versus 3,1±2,2; p=0,008) em comparação ao grupo falha de tratamento clínico. Redução significativa e semelhante do escore de dor na dismenorreia, dor pélvica crônica, disquezia cíclica e disúria cíclica foi observada nos Grupos Tratamento Clínico e Cirúrgico. Dispareunia, no entato, teve uma redução maior no Grupo Cirurgia. A redução subjetiva dos sintomas dolorosos também foi semelhante entre os Grupos Clínico e Cirúrgico (100% versus 98,2%; p=0,18). O Grupo Tratamento Cirúrgico foi relacionado a uma maior taxa de complicações graves (9,2% versus 0,6%; p=0,001) em comparação ao Grupo Tratamento Clínico. Conclusão: Falha no tratamento clínico em pacientes com endometriose de retossigmoide foi observada em mulheres mais jovens que tinham lesões intestinais maiores. O tratamento clínico hormonal foi igualmente eficaz na melhora dos sintomas de dor, exceto dispareunia, em comparação ao tratamento cirúrgico em mulheres com endometriose intestinal, mas com menor taxa de complicações. O tratamento clínico deve ser oferecido como primeira opção em pacientes com endometriose intestinal, enquanto o tratamento cirúrgico deve ser reservado para pacientes sem melhora nos sintomas de dor com tratamento hormonal, progressão das lesões ou suspeita de suboclusão intestinal.


Subject(s)
Humans , Female , Adult , Progestins/therapeutic use , Rectal Diseases/drug therapy , Sigmoid Diseases/drug therapy , Pelvic Pain/drug therapy , Contraceptives, Oral, Combined/therapeutic use , Endometriosis/drug therapy , Rectal Diseases/surgery , Sigmoid Diseases/surgery , Pain Measurement , Recombinant Fusion Proteins , Medical Records , Retrospective Studies , Follow-Up Studies , Treatment Outcome , Pelvic Pain/surgery , Dysmenorrhea/drug therapy , Dyspareunia/drug therapy , Endometriosis/surgery , Chronic Pain
18.
Medwave ; 19(11): e7739, 2019.
Article in English, Spanish | LILACS | ID: biblio-1049167

ABSTRACT

INTRODUCCIÓN El edema macular es una complicación frecuente de la oclusión de la vena central de la retina que clínicamente provoca deterioro de la agudeza visual. Los tratamientos más utilizados son el implante de dexametasona y los fármacos anti factor del crecimiento endotelial vascular, destacando aflibercept dentro de estos. Sin embargo, no existe consenso acerca de qué tratamiento constituye la mejor alternativa. MÉTODOS Realizamos una búsqueda en Epistemonikos, la mayor base de datos de revisiones sistemáticas en salud, la cual es mantenida mediante el cribado de múltiples fuentes de información, incluyendo MEDLINE, EMBASE, Cochrane, entre otras. Extrajimos los datos desde las revisiones identificadas, analizamos los datos de los estudios primarios, realizamos un meta análisis y preparamos una tabla de resumen de los resultados utilizando el método GRADE. RESULTADOS Y CONCLUSIONES Identificamos dos revisiones sistemáticas que en conjunto incluyeron cuatro estudios primarios, todos ensayos aleatorizados. Concluimos que no es posible establecer si aflibercept es superior a dexametasona en términos de mejora de agudeza visual y seguridad, debido a que la certeza de la evidencia existente ha sido evaluada como muy baja.


INTRODUCTION Macular edema is a frequent complication of central retinal vein occlusion that might lead to deterioration of visual acuity. The most commonly used treatments are dexamethasone implant and anti-vascular endothelial growth factor drugs, being aflibercept one of the most commonly used them. However, there is no consensus about which treatment constitute the best alternative. METHODS We searched in Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. RESULTS AND CONCLUSIONS We identified two systematic reviews that included four primary studies overall, all randomized trials. We concluded that it is not possible to establish whether aflibercept is superior to dexamethasone in terms of improvement of visual acuity and safety, because the certainty of the existing evidence has been evaluated as very low.


Subject(s)
Humans , Recombinant Fusion Proteins/administration & dosage , Dexamethasone/administration & dosage , Macular Edema/drug therapy , Receptors, Vascular Endothelial Growth Factor/administration & dosage , Retinal Vein Occlusion/complications , Randomized Controlled Trials as Topic , Macular Edema/etiology , Databases, Factual , Angiogenesis Inhibitors/administration & dosage , Anti-Inflammatory Agents/administration & dosage
19.
Chinese Journal of Biotechnology ; (12): 1088-1096, 2019.
Article in Chinese | WPRIM | ID: wpr-771819

ABSTRACT

To improve and broaden the antimicrobial activity of β-defensin130, 3 copies of β-defensin130 encoding sequences were synthesized and cloned into pET28a (+) expression vector, and expressed in Escherichia coli BL21 (DE3) as a 25 kDa soluble protein. The affinity purified 3×β-defensin 130 displayed antimicrobial activity against not only Gram-positive strains including Staphylococcus aureus (ATCC 25923) (45 μg/mL) and Listeria monocytogenes (ATCC 221633) (80 μg/mL) but also Gram-negative strains. Furthermore, the antimicrobial activity of β-defensin130 was not affected by temperature, pH and proteinase digestion. In addition, E. coli-derived 3×β-defensin130 was not toxic to HEK 293 cells and showed a relatively low hemolytic activity against rabbit erythrocytes. Our study proves 3×β-defensin130 expressed in E. coli is stable, non-cytotoxic and low-hemolytic active with great potential as alternative antibiotics.


Subject(s)
Animals , Anti-Bacterial Agents , Escherichia coli , HEK293 Cells , Humans , Rabbits , Recombinant Fusion Proteins , Staphylococcus aureus , beta-Defensins
20.
Chinese Journal of Biotechnology ; (12): 1463-1468, 2019.
Article in Chinese | WPRIM | ID: wpr-771783

ABSTRACT

We studied the construction of fusion protein TAT-RIG-I-GFP prokaryotic expression vector and verified the function of TAT in transmembrane delivery. First, four pairs of specific primers were designed, and the RIG-I gene of Mallard Duck (Anas platyrhynchos) was cloned. Then, the pET-TAT-RIG-I-GFP and pET-RIG-I-GFP prokaryotic expression vectors were constructed. Meanwhile, they were converted to E. coli BL21 (DE3), which were induced to be expressed after culture. After the purification of His-60 nickel affinity chromatography column and the identification of SDS-PAGE, the purified TAT-RIG-I-GFP and RIG-I-GFP proteins were incubated to DF-1 cells. Finally, fluorescence microscopy was used to observe whether the corresponding fluorescence was produced in DF-1 cells. The results showed that pET-TAT-RIG-I-GFP fusion with TAT showed obvious green fluorescence in DF-1 cells. However, the pET-RIG-I-GFP without TAT cannot display green fluorescence. This shows that TAT-fused protein have successfully delivered DF-1 cells and play a key role in transmembrane delivery. In conclusion, these results provide a solid material basis for further study of antiviral drugs in poultry.


Subject(s)
Cell Membrane , DNA Primers , Escherichia coli , Gene Expression , Gene Products, tat , Genetic Vectors , Recombinant Fusion Proteins
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