Streptococcal cell wall arthritis: studies with nude (athymic) inbred Lewis rats.

Group A streptococcal cell walls, upon intraperitoneal administration, fail to induce a chronic arthritis in athymic inbred Lewis rats (mu/mu). In contrast, heterozygous euthymic littermates (+/mu) develop a chronic arthritis upon administration of the cell wall material. Chronic arthritis can be readily induced in athymic rats if they are reconstituted intravenously with spleen cells derived from normal heterozygous euthymic littermates. Both athymic and euthymic rats develop the acute arthritis elicited by cell walls. These studies indicate that the requirements in the host for the induction of acute and chronic arthritis are different. Induction of acute arthritis is not dependent on functional T lymphocytes whereas the induction of chronic arthritis is dependent on functional T cells.