[The nature of immunodeficiency induced by injections of lectins and cyclophosphamide].

Consecutive injections of T-cell mitogen (LcA, Con A) and cyclophosphamide (CY) produce an inhibition of T-cell, but not B-cell functions. This phenomenon was not a result of suppressor-cell activity of the action of some suppressor serum factors. Immunoreactivity of mice, treated with Con A CY is restored by thymocytes from intact donors, but not bone marrow cells. Using, monoclonal antibodies to Thy-1.2 antigen or anti-Ig serum it has been shown that pretreatment of mice with lectin and CY resulted in a decrease in T-cell, but not B-cell number in comparison with control mice. The above facts are indicative of CY-mediated elimination of T cells involved in proliferation and differentiation by lectin.