Autoreactivity in an HIV-1 broadly reactive neutralizing antibody variable region heavy chain induces immunologic tolerance.
We previously reported that some of the rare broadly reactive, HIV-1 neutralizing antibodies are polyreactive, leading to the hypothesis that induction of these types of neutralizing antibody may be limited by immunologic tolerance. However, the notion that such antibodies are sufficiently autoreactive to trigger B cell tolerance is controversial. To test directly whether rare neutralizing HIV-1 antibodies can activate immunologic tolerance mechanisms, we generated a knock-in mouse in which the Ig heavy chain (HC) variable region rearrangement (V(H)DJ(H)) from the polyreactive and broadly neutralizing human monoclonal antibody 2F5 was targeted into the mouse Igh locus. In vitro, this insertion resulted in chimeric human/mouse 2F5 antibodies that were functionally similar to the human 2F5 antibody, including comparable reactivity to human and murine self-antigens. In vivo, the 2F5 V(H)DJ(H) insertion supported development of large- and small pre-B cells that expressed the chimeric human/mouse Igmu chain but not the production of immature B cells expressing membrane IgM. The developmental arrest exhibited in 2F5 V(H)DJ(H) knock-in mice is characteristic of other knock-in strains that express the Ig HC variable region of autoreactive antibodies and is consistent with the loss of immature B cells bearing 2F5 chimeric antibodies to central tolerance mechanisms. Moreover, homozygous 2F5 V(H)DJ(H) knock-in mice support reduced numbers of residual splenic B cells with low surface IgM density, severely diminished serum IgM levels, but normal to elevated quantities of serum IgGs that did not react with autoantigens. These features are consistent with elimination of 2F5 HC autoreactivity by additional negative selection mechanism(s) in the periphery.
Verkoczy
Laurent
L
Duke Human Vaccine Institute and Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA. laurent.verkoczy@duke.edu
Diaz
Marilyn
M
Holl
T Matt
TM
Ouyang
Ying-Bin
YB
Bouton-Verville
Hilary
H
Alam
S Munir
SM
Liao
Hua-Xin
HX
Kelsoe
Garnett
G
Haynes
Barton F
BF
D000818:Animals; D057134:Antibodies, Neutralizing / Q000235:genetics / Q000276:immunology*; D001324:Autoantigens / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology / Q000502:physiology; D002460:Cell Line; D005260:Female; D055879:Gene Knock-In Techniques; D015321:Gene Rearrangement; D015497:HIV-1 / Q000235:genetics / Q000276:immunology*; D006801:Humans; D007108:Immune Tolerance / Q000235:genetics / Q000276:immunology*; D007143:Immunoglobulin Heavy Chains / Q000235:genetics / Q000276:immunology*; D007135:Immunoglobulin Variable Region / Q000235:genetics / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000276:immunology; D013154:Spleen / Q000166:cytology
D057134:Antibodies, Neutralizing; D001324:Autoantigens; D007143:Immunoglobulin Heavy Chains; D007135:Immunoglobulin Variable Region; D011993:Recombinant Fusion Proteins