Genetic elimination of ?3(IV) collagen fails to rescue anti-collagen B cells.

ABSTRACT: Organ deposition of autoantibodies against the noncollagenous-1 domain of the ?3 chain of type IV collagen leads to severe kidney and lung injury in anti-glomerular basement membrane disease. The origin and regulation of these highly pathogenic autoantibodies remains unknown. Anti-?3(IV) collagen B lymphocytes are predicted to mature in vivo ignorant of target antigen because ?3(IV) collagen expression is highly tissue restricted and pathogenic epitopes are cryptic. However, a recent analysis of an anti-?3(IV)NC1 collagen autoantibody transgenic mouse model revealed that developing B cells are rapidly silenced by deletion and editing in the bone marrow. To dissect the role of collagen as central tolerogen in this model, we determined B cell fate in autoantibody transgenic mice genetically lacking ?3(IV) collagen. We found that absence of the tissue target autoantigen has little impact on the fate of anti-?3(IV)NC1 B cells. This implies a more complex regulatory mechanism for preventing anti-glomerular basement membrane disease than has been previously considered, including the possibility that a second antigen present in bone marrow engages and tolerizes anti-?3(IV)NC1 collagen B cells.

SUBMITTER: Clark AG 

PROVIDER: S-EPMC3260941 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature