title: Human B-cell ontogeny in humanized NOD/SCID γc(null) mice generates a diverse yet auto/poly- and HIV-1-reactive antibody repertoire.
abstract: Characterization of the human antibody (Ab) repertoire in mouse models of the human immune system is essential to establish their relevance in translational studies. Single human B cells were sorted from bone marrow and periphery of humanized NOD/SCID γc(null) (hNSG) mice at 8-10 months post engraftment with human cord blood-derived CD34(+) stem cells. Human IG variable heavy (V(H)) and kappa (V(κ)) genes were amplified, cognate V(H)-V(κ) gene-pairs assembled as single-chain variable fragment-Fc Abs (scFvFcs) and functional studies were performed. Although overall distribution of V(H) genes approximated the normal human Ab repertoire, analysis of the V(H)-third complementarity-determining regions in the mature B-cell subset demonstrated an increase in length and positive charges, suggesting autoimmune characteristics. Additionally, >70% of V(κ) sequences utilized V(κ)4-1, a germline gene associated with autoimmunity. The mature B-cell subset-derived scFvFcs displayed the highest frequency of autoreactivity and polyspecificity, suggesting defects in checkpoint control mechanisms. Furthermore, these scFvFcs demonstrated binding to recombinant HIV envelope corroborating previous observations of poly/autoreactivity in anti-HIVgp140 Abs. These data lend support to the hypothesis that anti-HIV broadly neutralizing antibodies may be derived from auto/polyspecific Abs that escaped immune elimination and that the hNSG mouse could provide a new experimental platform for studying the origin of anti-HIV-neutralizing Ab responses.
authors.affiliation: Department of Cancer Immunology and AIDS, Dana-Farber Cancer Institute, Boston, MA 02115, USA.
authors.forename: H
authors.initials: H
authors.lastname: Chang
authors.forename: S
authors.initials: S
authors.lastname: Biswas
authors.forename: A S
authors.initials: AS
authors.lastname: Tallarico
authors.forename: P T N
authors.initials: PT
authors.lastname: Sarkis
authors.forename: S
authors.initials: S
authors.lastname: Geng
authors.forename: M M
authors.initials: MM
authors.lastname: Panditrao
authors.forename: Q
authors.initials: Q
authors.lastname: Zhu
authors.forename: W A
authors.initials: WA
authors.lastname: Marasco
mesh_terms: D000818:Animals; D001323:Autoantibodies / Q000097:blood / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D005260:Female; D015326:Gene Rearrangement, B-Lymphocyte, Heavy Chain; D015483:HIV Antibodies / Q000097:blood / Q000276:immunology* / Q000378:metabolism; D015497:HIV-1 / Q000276:immunology*; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000737:chemistry / Q000235:genetics; D008297:Male; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D011485:Protein Binding / Q000276:immunology; D027041:Somatic Hypermutation, Immunoglobulin; D060152:V(D)J Recombination; D054299:env Gene Products, Human Immunodeficiency Virus / Q000276:immunology / Q000378:metabolism
chemical_list: D001323:Autoantibodies; D015483:HIV Antibodies; D007143:Immunoglobulin Heavy Chains; D054299:env Gene Products, Human Immunodeficiency Virus; C097729:gp140 envelope protein, Human immunodeficiency virus 1