Mining HIV controllers for broad and functional antibodies to recognize and eliminate HIV-infected cells

Abstract

HIV monoclonal antibodies for viral reservoir eradication strategies will likely need to recognize reactivated infected cells and potently drive Fc-mediated innate effector cell activity. We systematically characterize a library of 185 HIV-envelope-specific antibodies derived from 15 spontaneous HIV controllers (HCs) that selectively exhibit robust serum Fc functionality and compared them to broadly neutralizing antibodies (bNAbs) in clinical development. Within the 10 antibodies with the broadest cell-recognition capability, seven originated from HCs and three were bNAbs. V3-loop-targeting antibodies are enriched among the top cell binders, suggesting the V3-loop may be selectively exposed and accessible on the cell surface. Fc functionality is more variable across antibodies, which is likely influenced by distinct binding topology and corresponding Fc accessibility, highlighting not only the importance of target-cell recognition but also the need to optimize for Fc-mediated elimination. Ultimately, our results demonstrate that this comprehensive selection process can identify monoclonal antibodies poised to eliminate infected cells.

Keywords: Fc accessibility; Fc-functionality; HIV controllers; binding topology; infected cell binding; monoclonal antibodies.