| Popis: |
Treatment of mice with certain photosensitizers combined with exposure to visible light limits the development of theimmunologically-mediated contact hypersensitivity (CHS) response against topically-applied chemical haptens. Understandingof the inhibitory action of photosensitizers upon the CHS response is incomplete. Benzoporphyrin derivative monoacid ring A(BPD-MA, verteporfm), a photosensitizer with immunomodulatory activity, strongly depressed CHS responses to the haptendinilrofluorobenzene (DNFB). However, if mice were administered 1 ig of a recombinant preparation of the pro-inflammatorycytokine interleukin-12 (rIL-12), full-fledged CHS responses to DNFB ensued in animals treated with BPD-MA and light. Incontrast, when rIL-12 was given in combination with an anti-IL-12 antibody the restorative effect ofrlL-12 on the CHS responseof PDT-treated mice was blocked. Evaluation of the cytokine status of spleen and draining lymph node cells showed for DNFBpainted animals, that the release of the immunosuppressive cytokine IL-lO was increased by PDT and rIL-12 counter-acted theincrease in IJ,.lO liberation associated with PDT. These studies indicate that IL-lO formation is upregulated and the availabilityofIL-12 may be limited in mice treated with PDT. These features may contribute to deficient CHS responses observed with PDTKey words: antigen presentation, benzoporphyrin derivative, contact hypersensitivity, cytokines, immune modulation,immunosuppression, interferon-y, interleukin-4, interleukin-lO, interleukin-12, photodynamic therapy, photosensitizers.Abbreviations: APC, antigen presenting cells; BPD-MA, benzoporphyrin derivative monoacid ring A, verteporfm; CHS,contact hypersensitivity; DC, dendritic cell; DNFB, 2,4-dinitrofluorobenzene; IFN-'y, interferon-y; IL, interleukin; LC,Langerhans cells; PDT, photodynamic therapy; r, recombinant. |
