Serum immunoglobulin levels in IIJ mice and age-matched SJL/J controls. Serum was collected and Ig measured by ELISA. (A) through (C) Average levels of (A) total Ig, (B) IgG1, (C) IgG2b, (D) anti-collagen type II Ig and (E) anti-joint homogenate Ig. AR and NAR IIJ mice were littermates and were between 87 and 207 days old. No correlations between antibody level and age, sex, disease severity or days since disease onset were found (data not shown). (F) Amount of total Ig rheumatoid factor (RF) in NAR and AR littermates and age-matched SJL/J controls. All mice were 55 to 189 days old, and AR mice had had clinical disease for a minimum of four weeks. RF level did not correlate with total Ig or age (data not shown). Groups were compared by performing a t-test. Filled circles, squares, and triangles represent data points from NAR. Early AR, and Late AR mice, respectively.
Adipue et al. Arthritis Research & Therapy 2011 13:R114 doi:10.1186/ar3399