Influence of various forms of dialyzable leukocyte extracts on rat adjuvant arthritis

Adjuvant-induced arthritis in rats is a chronic inflammatory disease, widely used as an animal model for rheumatoid arthritis. In our study the effect of various fractions of dialyzable leukocyte extract (DLE): DLE I-molecular weight below 10 kDa (commercial preparation), DLE II-molecular weight below 5 kDa (suppressor fraction), DLE III-molecular weight 5-10 kDa on rat adjuvant-induced arthritis was studied. The adjuvant arthritic (AA) rats were treated with DLE fractions i.p. in solutions containing an active substance isolated from 12.5 x 10(6) and 6.25 x 10(6) leukocytes from day 1 (adjuvant injected) through day 18, every second day (total 9 times). Various markers of inflammation, immune function and joint destruction were evaluated: hindpaw volume, serum hyaluronic acid, serum albumin and biopterin in urine. All these markers showed a significant improvement after using fraction DLE II in comparison with AA controls. Fractions DLE I and DLE III influenced only some markers of inflammation and immune function. Our results demonstrated a therapeutical effect of fraction DLE II on rat adjuvant-induced arthritis.