[Effect of intraperitoneal administration of Streptococcus group A and its cell fractions on the development of adjuvant arthritis in rats].

The effect produced by the intraperitoneal injection of live and heat-killed group A streptococci, the fractions of their cell walls (both intact and sonicated) and cytoplasm was studied on 450 white rats with experimental adjuvant arthritis (AA). The injection of live streptococci into rats with AA decreased the swelling of joints (by 70-80% in the second half of the experiment), reduced the titers of rheumatoid-like factor (RLF), and inhibited the development of polyarthritis. The use of heat-killed streptococci gave a less pronounced antiarthritic effect, while the fraction of streptococcal cell walls, similarly to live streptococci, decreased the swelling of joints (by 27-64%); at the same time a considerable drop in the titers of RLF was observed in 3 experiments, and the development of polyarthritis was registered in 38% of the test animals and in 62% of the control animals. In rats with AA the cytoplasm not subjected to ultracentrifugal purification decreased the swelling of joints (by 21-50%) and the titers of RLF. In this case the development of polyarthritis was observed in 48% of the test animals and in 70% of the control animals.