STUDYING HCV-SPECIFIC B CELL REPERTOIRES FOR IMMUNOTHERAPEUTICS

Hepatitis C virus (HCV) has emerged as a major etiological agent of liver disease throughout the world. Of the persons acutely infected with HCV, 20–30% spontaneously recover, while 70–80% develop chronic infection. Still there is no HCV vaccine available. To understand how HCV infection perturbs the antibody repertoire and to identify molecular features of antibody genes associated with either viral clearance or chronic infection, there is a need to explore HCV-specific B cell response, thereby filling a critically important gap in our understanding of HCV immunity. Here, we propose to explore the HCV-specific B cell immunity to foster development of immunotherapeutic and diagnostic platforms. Blood samples were collected from 51 chronic infection and 15 spontaneously resolve HCV donors. Peripheral blood mononuclear cells (PBMCs) were isolated from HCV-infected patient and incubated with labeled recombinant HCV envelop protein (rE2). B cells were stained using CD19-PE, CD20-PECy5, CD27-BV421 and tagged rE2 (anti-cMyc, FICT). Viable, CD19+, CD20+, CD27+ and HCsAg+ (Hepatitis C antigen) were isolated by FACS sorter. We have collected specific B cell from patients with chronic HCV infection. These HCV-specific B cells were grown in 96 well and stimulated with interleukin-21 (IL-21) and HCV rE2. The secreted antibodies were used for neutralization assay. The antibodies that were produced from these B cell have shown neutralization capacity which supports the successful separation of HCV specific B cells. Identifying antigen-specific sequences from total repertoire data can aid our understanding B cell driven immunity against HCV, and may be used for disease diagnostics and vaccine design.