Eh. Beutner et al., ANTINUCLEAR ANTIBODIES (ANA) AND COMPLEMENT-FIXING ANA IN SYSTEMIC CONNECTIVE-TISSUE DISEASES, Immunological investigations, 27(1-2), 1998, pp. 97-104
Screening for antinuclear antibodies (ANA) with parallel tests for com
plement fixing ANA (C-ANA) reveal that C-ANA react either as strongly
as or more strongly than ANA in most cases of systemic lupus erythemat
osus (SLE) and related disorders including CREST syndrome. But sera of
drug induced LE and other ANA positive subjects have weak or no C-ANA
. (P < 0.0005). Titrations with parallel C-ANA/ANA tests of two cases
reveal primarily ANA and less C-ANA reactions in a case of drug induce
d LE but in CREST syndrome both ANA and C-ANA tests yield elevated tit
ers with stronger C-ANA reactions. These findings point to distinct im
munochemical mechanisms in C-ANA and ANA reactions.