| First Author | Hart PH | Year | 2000 |
| Journal | J Invest Dermatol | Volume | 114 |
| Issue | 3 | Pages | 508-13 |
| PubMed ID | 10692110 | Mgi Jnum | J:61049 |
| Mgi Id | MGI:1354271 | Doi | 10.1046/j.1523-1747.2000.00909.x |
| Citation | Hart PH, et al. (2000) Ultraviolet B-induced suppression of immune responses in interleukin-4-/- mice: relationship to dermal mast cells. J Invest Dermatol 114(3):508-13 |
| abstractText | Ultraviolet B radiation is immunosuppressive by multiple mechanisms. In interleukin-4-/- mice, ultraviolet B radiation was not able to suppress delayed-type hypersensitivity or contact hypersensitivity responses when the sensitizing antigen was applied to nonirradiated sites. In contrast, ultraviolet B significantly suppressed contact hypersensitivity responses to haptens applied to irradiated sites in interleukin-4-/- mice. In mast cell depleted Wf/Wf mice, ultraviolet B radiation also significantly suppressed contact hypersensitivity responses to sensitizing antigens applied to irradiated but not to unirradiated sites. In both interleukin-4-/- mice and Wf/Wf mice, the mast cell product, histamine, was immunosuppressive implicating mast cells as the dysfunctional cell in interleukin-4-/- mice. The prevalence of dermal mast cells was similar in wild-type and interleukin-4-/- mice. Dermal mast cells of interleukin-4-/- mice, however, express very low levels of c-kit and did not significantly degranulate in response to ultraviolet B. Ultraviolet radiation induced significant and similar levels of serum interleukin-10 in wild-type and interleukin-4-/- mice. We conclude that interleukin-4 indirectly affects ultraviolet B suppression of contact hypersensitivity and delayed-type hypersensitivity responses to sensitizing antigens applied at sites other than those irradiated by providing a critical differentiative signal for dermal mast cells. This study further emphasizes the central role of mast cells in the initial processes by which ultraviolet B radiation is immunomodulatory for immune responses to sensitizing antigens applied to nonirradiated sites. |
