T. Appelboom et al., ANTIBODIES TO SMALL RIBONUCLEOPROTEIN AND TO 73-KD HEAT-SHOCK PROTEIN- 2 DISTINCT MARKERS OF MIXED CONNECTIVE-TISSUE DISEASE, Clinical and experimental immunology, 100(3), 1995, pp. 486-488
We set out to discover whether antibodies to small ribonucleoprotein a
ntigens (RNP) and to 73-kD heat shock protein (hsp 73) which have been
proposed as markers of mixed connective tissue disease (MCTD) recogni
ze different epitopes. MCTD serum was immunoadsorbed on hsp 73-coupled
Sepharose and the affinity retained, and non-retained fractions were
checked by immunoblotting for recognition of either purified bovine hs
p 73 or calf thymus extract RNPs. The hsp 73 affinity-bound serum frac
tion recognized hsp 73 but not RNP antigens, the reverse being true fo
r the non-retained fraction. We conclude that anti-hsp 73 and anti-RNP
s are distinct markers of MCTD.