Production of autoantibodies against DNA and collagen after inoculation of rabbits with Trypanosoma equiperdum.

The aim of the study was to investigate the induction of autoantibodies in rabbits after the inoculation with Trypanosoma equiperdum. Eight female rabbits were inoculated s.c. with 5 x 10(6) parasites of Trypanosoma equiperdum. Four of these animals were treated with Diminazen (Berenil) at a dosage of 28 mg per rabbit by intramuscular injection 35 days p. i. Two additional non-infected rabbits served as negative controls. 9 days p.i. all infected animals possessed serum antibodies against Typanosoma equiperdum. Titers peaked to 1:2048, measured between 14 and 30 days p.i. and were persistent until the end of examinations. In parallel, there was an increase of anti-dsDNA and anti-collagen autoantibodies, but not of autoantibodies against recombinant U1RNP and La antigens. In comparison to patients with systemic lupus erythematosus, the anti-DNA binding of rabbit's sera was reduced more strongly in presence of increasing salt concentrations. In addition, the sera of inoculated rabbits recognized several unknown bands of a cell extract in immunoblotting. The parallel increase of antibodies against Trypanosoma, control foreign antigens, DNA and collagen suggests a polyclonal stimulation of the immune system. It was concluded that this rabbit model seems to be sufficient to investigate the mechanisms which are able to induce autoimmune phenomena.