Effect of UV-B on lymphocytes and hematopoietic progenitors.
(A) Dose-dependent reduction of lymphocyte proliferation and hematopoietic progenitors. The differences between the residual percentage of colony formation and lymphocyte proliferation at 33J/m2 were significant (see text). At 66 J/m2, only the difference between lymphocyte proliferation response and CFU-GM was significant (P < .005). (B) Preservation of more primitive hematopoietic progenitors after UV-B irradiation. MNC were separated from cord blood (n = 5) and PBSC (n = 5) and irradiated with various doses of UV-B. Residual percentages of CFU-C, HPP-CFC, and LTC-IC at doses of 33 J/m2 were 69% ± 25.1%, 81.4% ± 17.9%, and 84.5% ± 4.3%, respectively. These differences were not significant. Results are all expressed as means ± SD. Error bars in the graph represent SE.
