PT  - JOURNAL ARTICLE
AU  - Wisnieski, J J
AU  - Jones, S M
TI  - Comparison of autoantibodies to the collagen-like region of C1q in hypocomplementemic urticarial vasculitis syndrome and systemic lupus erythematosus.
DP  - 1992 Mar 01
TA  - The Journal of Immunology
PG  - 1396--1403
VI  - 148
IP  - 5
4099  - http://www.jimmunol.org/content/148/5/1396.short
4100  - http://www.jimmunol.org/content/148/5/1396.full
SO  - J. Immunol.1992 Mar 01; 148
AB  - Hypocomplementemic urticarial vasculitis syndrome (HUVS) is an apparent autoimmune disorder that resembles SLE. We previously showed that C1q precipitins in HUVS sera are IgG autoantibody to human C1q. We have compared HUVS anti-C1q autoantibody to a similar autoantibody in the serum of some patients with SLE. As with anti-C1q autoantibody in SLE sera, the HUVS autoantibody binds only to the collagen-like region (CLR) of C1q. In both HUVS and SLE, IgG2 is the predominant subclass of IgG autoantibody and IgM autoantibody to C1q is uncommon. In both diseases, anti-C1q autoantibodies bind preferentially to surface-adsorbed C1q or CLR fragments compared to these antigens in solution. Finally, when HUVS or SLE autoantibodies were added to CLR-coated wells already bound, respectively, by SLE or HUVS autoantibodies, no increases in CLR binding were observed, suggesting that HUVS and SLE autoantibodies to C1q bind to the same CLR epitope(s).