Abstract
The effects of cyclophosphamide on the activities of the three kinds of T-cells shown below were investigated. Namely, (i) immunocompetent T-cells appearing at the time of immunization with homologous carrier antigen, (ii) T-cells participating in delayed type skin reactions and (iii) T-cells taking part in in vitro transformation.
The results of theinvestigation are as follows :
1) Cyclophosphamide did not show suppressive effect on the activity of helper T cells in production of anti-DNP antibody.
2) Cyclophosphamide exhibited suppressive effect on antigen-induced in vitro transformation, if administered during or after immunization. The strongest suppressive effect was observed, if administered simultaneously with antigen.
3) The treatment of cyclophosphamide did not affect the induction of local transfer of delayed type skin hypersensitivity. The local transfer test with nylon adherent lymphocytes separated from nylon wool column gave negative results, if the lymphocytes were obtained from the guinea pigs not treated with cyclophosphamide, but positive results if they were from the guinea pigs treated with cyclophosphamide.
These results suggest that the suppressor cells induced in LNC (A) might be eliminated by cyclophosphamide.
