Tagami H, Kudoh K, Takematsu H
Department of Dermatology, Tohoku University School of Medicine, Sendai, Japan.
Dermatologica. 1989;179 Suppl 1:1-8. doi: 10.1159/000248439.
Infections by dermatophytes (dermatophytosis) naturally stimulate the immune system as in those by other microorganisms to induce various immunological phenomena. However, differing from other infections, the infecting organisms cannot become a direct target of antibody response or phagocytosis because they reside only in the barrier membrane of the body surface, i.e. in the stratum corneum. Thus, the immunity against dermatophytes is relative as compared with the absolute one noted in other infections such as measles and mumps. In dermatophytosis, a unique behavior of the epidermis as noted in contact dermatitis plays an important role in the defense against infection. Dermatitic changes induced by fungal products, particularly those due to contact sensitivity to a fungal antigen, trichophytin, enhance epidermopoiesis, which leads to increased turnover of the epidermis with their resultant elimination from the skin surface. Furthermore, the dermatophytes in the stratum corneum provoke transepidermal leukocyte chemotaxis by generating chemotactic C5a anaphylatoxin in exudating serum via alternative complement pathway activation in addition to a release of low molecular weight chemotactic factors. Such neutrophilic migration with the formation of subcorneal pustules also enhances epidermal proliferation as in psoriasis.
皮肤癣菌感染（皮肤癣菌病）与其他微生物感染一样，自然会刺激免疫系统以诱发各种免疫现象。然而，与其他感染不同的是，感染的生物体不会成为抗体反应或吞噬作用的直接靶点，因为它们仅存在于体表的屏障膜中，即角质层中。因此，与麻疹和腮腺炎等其他感染中所见到的绝对免疫相比，针对皮肤癣菌的免疫是相对的。在皮肤癣菌病中，如接触性皮炎中所见到的表皮的独特行为在抵御感染中起重要作用。真菌产物引起的皮肤炎症变化，特别是对真菌抗原癣菌素接触敏感所致的变化，会增强表皮形成，从而导致表皮更新加快，使其从皮肤表面清除。此外，角质层中的皮肤癣菌除了释放低分子量趋化因子外，还通过替代补体途径激活在渗出血清中产生趋化性C5a过敏毒素，从而引发经表皮白细胞趋化作用。这种伴有角膜下脓疱形成的嗜中性粒细胞迁移也会像在银屑病中一样增强表皮增殖。
