PT  - JOURNAL ARTICLE
AU  - K Tanimoto
AU  - T Moritoh
AU  - T Azuma
AU  - Y Horiuchi
TI  - Detection of IgG rheumatoid factor by concanavalin A treatment and complement fixation with IgG rheumatoid factor.
AID  - 10.1136/ard.35.3.240
DP  - 1976 Jun 01
TA  - Annals of the Rheumatic Diseases
PG  - 240--245
VI  - 35
IP  - 3
4099  - http://ard.bmj.com/content/35/3/240.short
4100  - http://ard.bmj.com/content/35/3/240.full
SO  - Ann Rheum Dis1976 Jun 01; 35
AB  - Concanavalin A (Con A) froms precipitates with carbohydrate-rich protein such as IgM, IgD, IgE, and IgA. Since IgG contains little carbohydrate and does not react with Con A, the activity of IgG-rheumatoid factor (RF) can be measured in the supernate of the Con A-treated serum. When the latex fixation test (LFT) and the sensitized sheep cell agglutination test (SSCA) were perfromed in the supernate for the detection of IgG-RF, LFT was positive in 32-1% of sera, out of 137 sera originally positive for LFT, and SSCA was positive in 18-5% of sera, out of 119 sera originally positive for SSCA. IgG-RF exhibited lower complement fixing ability than IgM-RF and correlated with agglutination titres of IgG-RF, while the CH50 of the original serum did not correlate with haemolytic activities of either IgM-RF or IgG-RF.