Pereira M C, Leite V H, Leite A C
Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
Med Vet Entomol. 2001 Mar;15(1):22-7. doi: 10.1046/j.1365-2915.2001.00273.x.
Skin biopsies from larvae of Rattus norvegicus, experimentally infested with Dermatobia hominis (Linnaeus Jr) (Diptera: Cuterebridae), were processed for histopathological studies. Two days after infestation, the first-stage larvae (L1) were located deep in the dermis, surrounded by an inflamed area infiltrated predominantly by neutrophils. On the fourth day a thin necrotic layer could be seen close to the larvae, surrounded by large numbers of neutrophils, lymphocytes, macrophages with a few eosinophils and mast cells. A small warble was formed after the fourth day, increasing in size until the seventh day, when the L1 moulted to the second-stage larva (L2). The inflammatory process continued with increasing numbers of neutrophils, macrophages, lymphocytes, eosinophils and mast cells invading the area, as well as the proliferation of fibroblasts and endothelial cells and the appearance of a few localized haemorrhages. After 18-20 days, the L2 moulted to the third-stage larva (L3), when a few plasma cells could be seen in the inflamed area. At 25-30 days there was a reduction in the necrotic layer, as well as in the number of neutrophils and lymphocytes, although large amounts of eosinophils, plasma cells, and collagen fibres were seen. The L3 usually left the host after 30 days. Two days later, the larval cavity was reduced, mast cells infiltrated the region and collagen fibre production were increased. After 7 days, an intense infiltration of plasma cells and scattered necrotic areas could be seen. A scar formed after 10 days. This study showed the laboratory rat to be a suitable model for studies of D. hominis infestation.
对实验感染人皮蝇（双翅目：狂蝇科）的褐家鼠幼虫进行皮肤活检，用于组织病理学研究。感染两天后，第一期幼虫（L1）位于真皮深层，周围是主要由中性粒细胞浸润的炎症区域。第四天，在幼虫附近可见一层薄的坏死层，周围有大量中性粒细胞、淋巴细胞、巨噬细胞，还有少量嗜酸性粒细胞和肥大细胞。第四天之后形成了一个小的疖肿，其大小不断增加，直到第七天，此时L1蜕皮变为第二期幼虫（L2）。炎症过程持续，中性粒细胞、巨噬细胞、淋巴细胞、嗜酸性粒细胞和肥大细胞不断侵入该区域，同时成纤维细胞和内皮细胞增殖，并出现一些局部出血。18 - 20天后，L2蜕皮变为第三期幼虫（L3），此时在炎症区域可见少量浆细胞。在25 - 30天时，坏死层以及中性粒细胞和淋巴细胞数量减少，不过可见大量嗜酸性粒细胞、浆细胞和胶原纤维。L3通常在30天后离开宿主。两天后，幼虫腔缩小，肥大细胞浸润该区域，胶原纤维生成增加。7天后，可见浆细胞强烈浸润和散在的坏死区域。10天后形成瘢痕。本研究表明实验大鼠是研究人皮蝇感染的合适模型。
