[Effect of staphylococcal enterotoxin A on the development of Lewis lung carcinoma in mice].

The effect of Staphylococcus aureus enterotoxin A (SEA) was studied for its effect on the development of the Lewis carcinoma in mice. It was shown that administration of SEA immediately after the appearance of the primary node in mice after transplantation of tumour cells led to insignificant inhibition of the node growth and a slight decrease of tumour metastasizing into the lungs. Inoculation of mice after the appearance of the primary node with 1/microgram of SEA 5 times a week significantly increased their survival rate. The lack of the marked effect of SEA appears to be associated with the disturbance of the immune interferon system functioning in tumour-bearing mice, since the production of serum interferon induced by SEA in mice with tumours was considerably lower than in the intact ones.