Figure 2.
Perspective HDR-based strategies that provide strong and broad protection against HIV. (A) Mature B lymphocytes engineered via knock-in of bNAb into IgH locus are capable to proliferate after adoptive transfer to syngeneic mice and immunization with cognate antigen and produce a high titer of anti-HIV Ig of different classes. Hopefully, preclinical trials on primates and clinical studies will be successful as well. The concept of full-length light chain and variable domain heavy chain knock-in-out at IgH locus was adapted from the papers (Hartweger et al., 2019; Nahmad et al., 2020). The single-chain antibody was introduced between VDJ and C segments that preserves mechanism of Ig class switch, while additional IgK gene KO prevents mispairing of light chain with transgenic heavy chain. (B). Knock-in-out of MT-C34 peptide from gp41 protein into the CXCR4 locus with a parallel ablation of CCR5 gene ensures full tropism-independent protection of engineered CD4+ T cells from HIV. (C). A combination of secreted and GPI-anchored forms of MT-C34 via peptide concatemeric construct knocked-in into CXCR4 gene will provide the selection of CD4+ T cells that are resistant to HIV and secrete the MT-C34 peptide which will shield non-edited cells from HIV infection. The GPI-anchored C-peptide KI concept was described previously in our paper (Maslennikova et al., 2022) and here it was complemented with CCR5 KO and peptide secretion strategy which was reported earlier and called SAVE (Egerer et al., 2011). The symbol and pictogram labels (grouped for panels B, C) are shown at the bottom of pictures. All images were created with BioRender.