In vitro selective effect of melphalan on human T-cell populations.
In vitro treatment with 2 micrograms/2 X 10(6) cells melphalan (L-PAM: L-phenylalanine mustard) significantly decreased the total number of T lymphocytes from peripheral blood (PBL) of healthy human donors and of the OKT4 population (precursor suppressor/helper/inducer) T cells as defined by monoclonal antibodies OKT3 and OKT4, respectively. No changes in the OKT+8 lymphocyte population (cytotoxic/mature suppressor cells) were observed following the same treatment. Preincubation of PBL with L-PAM at concentrations that do not affect the rate of DNA synthesis in PHA-stimulated lymphocytes inhibited the generation of T suppressor lymphocytes by ConA, as shown by their effect on PHA stimulation. Treatment of allogeneic PBL with L-PAM had no effect on mature suppressor T cells already induced by ConA, as shown by incubation of PBL with L-PAM after incubation with ConA.
Ben-Efraim
S
S
Komlos
L
L
Notmann
J
J
Hart
J
J
Halbrecht
I
I
D000911:Antibodies, Monoclonal; D002478:Cells, Cultured; D003208:Concanavalin A / Q000037:antagonists & inhibitors; D006801:Humans; D008213:Lymphocyte Activation / Q000187:drug effects; D008558:Melphalan / Q000633:toxicity*; D013601:T-Lymphocytes / Q000187:drug effects*; D013602:T-Lymphocytes, Cytotoxic / Q000187:drug effects; D050378:T-Lymphocytes, Regulatory / Q000187:drug effects
D000911:Antibodies, Monoclonal; D003208:Concanavalin A; D008558:Melphalan