Fig. 3.

Serum levels of anti-type II collagen (CII) antibodies after CII : chitosan feeding. Rats (n = 7–9) were fed diluent, chitosan, CII and CII : chitosan and immunized as described in Fig. 2; 28 days after the primary immunization serum samples were obtained and the anti-CII response was evaluated by enzyme-linked immunosorbent assay at a 1:500 dilution; (a) total immunoglobulin (Ig)G anti-CII; (b) IgG1 anti-CII; (c) IgG2a anti-CII; (d) IgG2b anti-CII. Difference versus diluent *P < 0·05; versus CII #P < 0·05.