Possible Role of Streptococcus pyogenes in Mucocutaneous Lymph Node Syndrome VIII. Immunological Tolerance to S. pyogenes-Associated Antigens Seems Essential to Induction of MCLS

In our previous studies, we attempted to show that new-born mice infected with an attenuated strain of Streptococcus pyogenes , and exposed to streptococcal antigens approximately one month later, failed to develop a humoral response to those antigens but were able to respond normally to other unrelated antigens. Since such immunological characteristics are identical to those of patients with the mucacutaneous lymph node syndrome (MCLS), the present studies were performed with the aim of assessing the antibody-forming activities of peripheral blood lymphocytes collected from MCLS patients. These lymphocytes were cultured in the presence of pokeweed mitogen, streptolysin-O and streptococcal C-polysaccha-ride, leading to their refractoriness to S. pyogenes-associated antigens coupled with normal responsiveness to unrelated antigens. The implication of such immunological responsiveness elicited from neonatal exposure to streptococcal antigens is discussed, particularly with reference to the induction of MCLS.