Detection of antibodies to RANA and its clinical significances in rheumatoid arthritis

The authors have set up a method by indirect immunofluorescence assay （（?）F） for the detect-ion of antibodies to rheumatoid arthritis associated nuclear antigen （RANA） and used it to testanti-RANK in various connective tissue diseases （GTD） and normal controls.The results showedthat the positive rate （40.45%） and geometric mean titers（1:83.6） of anti.RANA in RA were si-gnificahtiy higher than those in other CTDs and normal controls.The frequency and mean titersof anti RANA in seropositive RA were closely similar to those in seronegative RA.The detectionof anti-RANA was not obviously affected by the presence of antinuclear antibodies （ANA）,anti-SS-A,anti-SS-B and RF.This paper indicated that the frequency of anti-RANA increased withprolongation of the course of RA.There were no correlations between anti-RANA and diseaseactivity and anti-rheumatic drug therapies.
It is suggested that the detection of anti-RANA may be useful for diagnosis of RA and diffe-rentiation from other seronegative arthritides.