The effect of low-dose irradiation on unstimulated and PHA-stimulated human lymphocyte subsets.
A culture system was used to evaluate the radiosensitivity of CD4+ and CD8+ T cells, Leu 19+ cells, and B cells obtained from normal adult males. Unstimulated CD8+ lymphocytes (D0 = 55 cGy) were twice as radiosensitive as CD4+ cells (D0 = 115 cGy). B cells had an intermediate radiosensitivity (D0 = 100 cGy). Leu 19+ cells were much more radioresistant and expressed a D0 of 550 cGy. When lymphoid cells were irradiated 1 or 4 days before phytohemagglutinin (PHA) stimulation, they were more radiosensitive than if they were first stimulated with PHA and then irradiated. When lymphoid cells were irradiated 1 h after PHA stimulation each lymphocyte subset was characterized by an increase in the D0 to 150 cGy for B cells to 290 cGy for CD4+ cells, and to 240 cGy for CD8+ cells. In contrast, Leu 19+ cells exhibited a decrease in their D0 to 290 cGy after they were stimulated by PHA.
Stewart
C C
CC
Los Alamos National Laboratory, New Mexico 87545.
Stevenson
A P
AP
Habbersett
R C
RC
D000328:Adult; D000368:Aged; D000954:Antigens, Surface / Q000032:analysis; D002470:Cell Survival / Q000528:radiation effects; D002478:Cells, Cultured; D004307:Dose-Response Relationship, Radiation; D006801:Humans; D008213:Lymphocyte Activation / Q000187:drug effects; D008214:Lymphocytes / Q000145:classification / Q000187:drug effects / Q000528:radiation effects*; D008297:Male; D008875:Middle Aged; D010835:Phytohemagglutinins / Q000494:pharmacology; D011836:Radiation Tolerance
D000954:Antigens, Surface; D010835:Phytohemagglutinins