Preliminary evidence of modulating Th1 cytokine after allergen challenge

We wanted to determine whether a paradigm switch in Th1/Th2 phenotypes in splenic lymphocytes could be induced in BALB/c mice after ultraviolet-B (UVB) irradiation and exposure to pollen. Results showed that UVB irradiation increased IL-1 but decreased IL-12 in vivo, and caused significant cell destruction of macrophages in vitro. We then gave mice cedar pollen intranasally, UVB irradiation (6kJ/cm²), and then splenic lymphocyte functions were examined. Results revealed that: 1) the level of IFN-gamma of splenic lymphocytes from UVB-irradiated mice was significantly decreased, especially in pollen-exposed mice; 2) UVB irradiation did not augment IL-4 levels; 3) IgE levels from UVB-irradiated mice did not increase. UVB irradiation (6kJ/cm²) did not induce Th2 response but suppressed Th1 cytokine, suggesting that Th1 could be more susceptible to UVB irradiation than Th2.