Screening and identification of human monoclonal antibodies to hepatitis E virus capsid protein / 中国免疫学杂志

Objective:To establish a method for rapidly screening human antibodies recognizing HEV capsids proteins from pe-ripheral blood.The antibodies recognizing HEV capsids proteins were screened from the peripheral blood of vaccinator and the properties of the antibodies were analyzed.Methods:The HEV capsids proteins specific memory B cells in peripheral blood were obtained by flow cytometry sorting.Then antibody variable genes were acquired through single-cell RT-PCR and recombined to express in eukaryocyte.Finally,the properties analysis of recombinant expressed human monoclonal antibodies were carried out.Results:Six hu-manized monoclonal antibodies recognizing HEV capsids proteins were successfully obtained,and most of them had binding activity and neutralizing activity.Conclusion:The sequence of human monoclonal antibodies recognizing HEV capsid proteins is successfully screened and successfully expressed in the eukaryocyte.The properties of the antibodies are identified,which lay the foundation for studying antibody evolution in the human body after vaccination.

Isolation and identification of neutralizing monoclonal antibodies to two Tier 2 viruses in a patient with HIV-1 infection / 中华微生物学和免疫学杂志

Objective To isolate neutralizing monoclonal antibodies to Tier 2 viruses in a Chinese patient with HIV-1 infection. Methods Monoclonal antibodies were isolated using single B cell sorting and monoclonal antibody expression technique. The international ImMunoGeneTics database (IMGT) was used to analyze antibody variable region genes. Antibody binding ability and neutralizing activity were tested by enzyme linked immunosorbent assay and TZM-bl/pseudovirus assay,respectively. Results Two monoclonal antibodies (E11 and H2) that could neutralize two Tier 2 viruses were isolated from the patient with clade B HIV-1 infection. Heavy chains of E11 and H2 were derived from IGHV4-4*08 with a somatic mutation rate of 15.79% and 14.74%,respectively. Light chains were both derived from IGKV3-15*01 with a somatic mutation rate of 8.33% and 7.95%, respectively. E11 and H2 could bind to HIV-1 clade B, CRF01_AE and CRF07_BC viruses. The half maximal inhibitory concentration(IC50) values of E11 and H2 were 18.78 μg/ml and 22.43 μg/ml against 398-F1 virus and 43.35 μg/ml and 39.45 μg/ml against 25710 virus. Conclusion In this study, two neutralizing monoclonal antibodies to two Tier 2 viruses were identified in the patient with HIV-1 infection,which might provide reference for the development of AIDS vaccines.