ab1902

Suppression of adjuvant arthritis in rats by boar seminal immunosuppressive fraction

L. Veselsky¹, B. Zelezná¹, J. Dostál², M. Stancíková³, K. Svík³, R. Rokyta⁴, J. Jurcovicová^4,5

1Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague; 2Institute of Animal Physiology and Genetics, Academy of Sciences of the Czech Republic, Libechov, Czech Republic; 3 Research Institute of Rheumatic Diseases, Piest'any, Slovak Republic, 4Department of Normal, Pathological and Clinical Physiology, Third Medical Faculty of Charles University, Prague, Czech Republic, 5Institute of Experimental Endocrinology, Slovak Academy of Sciences, Bratislava, Slovak Republic.

ABSTRACT
Objective
The effect of the immunosuppressive fraction of boar seminal vesicle fluid (ISF) was tested on the manifestation of adjuvant arthritis (AA) in rats.

Methods
The inhibitory effect of ISF on mitogen-stimulated proliferation of rat lymphocytes was evaluated by immunoassay using bromodeoxyuridine incorporation. Adjuvant arthritis was induced in male Long Evans rats with Mycobacterium butyricum in adjuvant. ISF was administered at the time of the induction of arthritis. At the time of maximal manifestation of the disease, the hind paw swelling and thymus weight were estimated. IgM and IgG in the rat blood sera were quantified by sandwich ELISA. Serum corticosterone was analyzed by radioimmunoassay. Serum NO2-/NO3- were estimated by diazotation. Serum albumin was measured spectrophotometrically. The expression of IL-6 mRNA in peritoneal macrophages was estimated by dot-blot hybridization.

Results
Treatment of arthritic rats with ISF attenuated hind paw edema. The production of IgG subclasses dropped in ISF-treated AA rats. The thymus mass and serum albumin concentration were partially restored due to the ISF treatment. Serum corticosterone as well as NO2-/NO3- concentrations were reduced by the ISF effect. The expression of IL-6 in peritoneal macrophages was inhibited in AA rats after ISF treatment.

Conclusion
ISF attenuated the manifestation of AA in rats and mitigated the inflammation. Immunoglobulin production was most probably inhibited by the decreased proliferation of B lymphocytes.

Key words
Seminal immunosuppressor, adjuvant arthritis inhibition, IgM and IgG subclasses, anti-inflammatory effect.

This work was supported by the Grant Agency of the Czech Republic, grant No.204/98/0827, grant No. 605/98/1064, and by the Grant Agency of the Ministry of Health of the Czech Republic, grant No. NC/4534-3.
Please address correspondence and reprint requests to: Dr. Leopold Veselsky, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Flemingovo n‡m. 2, 166 37 Prague, Czech Republic.