Antibody Repertoires in Humanized NOD-scid-IL2Rγnull Mice and Human B Cells Reveals Human-Like Diversification and Tolerance Checkpoints in the Mouse

摘要: Immunodeficient mice reconstituted with human hematopoietic stem cells enable the in vivo study of hematopoiesis. In particular, NOD-scid-IL2Rγ(null) engrafted have been shown to reasonable levels T and B cell repopulation can mount T-cell dependent responses; however, antigen-specific B-cell responses this model are generally poor. We explored whether developmental defects immunoglobulin gene repertoire might be partly responsible for low level antibody model. Roche 454 sequencing was used obtain over 685,000 reads from cDNA encoding heavy (IGH) light (IGK IGL) genes isolated immature, naive, or total splenic mice, compared 940,000 peripheral two healthy volunteers. find that while naive repertoires humanized chiefly indistinguishable those blood cells, display highly correlated patterns segment use, complementarity-determining region H3 (CDR-H3) nevertheless extremely diverse specific each individual. Despite diversity, preferential D(H)-J(H) pairings repeatedly occur within CDR-H3 interval strikingly similar across all examined, implying a genetic constraint imposed on generation. Moreover, length, charged amino-acid content, hydropathy between humans no evidence global autoimmune signatures. Importantly, statistically greater usage inherently autoreactive IGHV4-34 IGKV4-1 observed newly formed immature relative finding consistent deletion humans. Overall, our results provide key features primary shaped by factors intrinsic principally unaltered differences mouse stromal microenvironments.