Читать книгу Diagnostics and Therapy in Veterinary Dermatology - Группа авторов - Страница 19

Acids, bases, free radicals, UVR, and natural or synthetic poisons are not always avoidable, thus the immune system is essential for protecting the host from these harmful substances. While it is intuitive that the innate immune system would protect against toxins and chemicals, both adaptive and immune responses are involved. Solar UVR causes formation of damaging free radicals. Natural moisturizing factors in the stratum corneum (specifically urocanic acid), keratinocyte DNA, and Langerhans cells all function as chromophores that absorb the UVR. When the UVR is absorbed, these cells produce TNF‐ α, IL‐10, and IL‐4 that encourage an adaptive immune response. TNF‐α and IL‐10 limit the recruitment of inflammatory cells to ensure an environment with just enough neutrophils and NK cells to eliminate any pathogens breaking through the temporarily damaged skin barrier.