A comparison of anti-type II collagen antibody titres and isotype profiles in pregnant and virgin DBA/1 mice with collagen-induced arthritis.

In order to discover whether changes in the nature of the humoral response to type II collagen occur during pregnancy we compared, by enzyme-linked immunosorbent assay (ELISA), the anti-type II collagen antibody titres and isotype profiles of pregnant and virgin DBA/1 mice immunized with type II collagen. Significant reductions in the mean clinical scores and anti-collagen antibody titres were observed during late pregnancy. Titres of all of the anti-collagen isotypes tended to be lower in pregnant than non-pregnant mice, although only in the case of IgG3 was there a significant difference between the two groups. We conclude that while pregnancy may cause changes to the isotype distribution of anti-collagen antibodies it is not possible on the basis of this study to relate such changes to the remission of arthritis observed during pregnancy.