Pépin M, Fontaine J J, Pardon P, Marly J, Parodi A L
Institut National de la Recherche Agronomique, Laboratoire de Pathologie Infectieuse et Immunologie, Nouzilly, France.
Vet Microbiol. 1991 Oct;29(2):123-34. doi: 10.1016/0378-1135(91)90120-5.
Histological responses during experimental Corynebacterium pseudotuberculosis infection in lambs were investigated in parotid lymph nodes for ten days following inoculation. Lambs were infected by the subcutaneous route into the right eyelid with a virulent strain of C. pseudotuberculosis. Multiple microscopic acute abscesses, predominantly infiltrated with polymorphonuclear (PMN) leucocytes, were seen in the right parotid lymph node on the 1st day post-inoculation (PI). This massive PMN infiltration coincided with a peripheral blood granulocytosis. On day 3 PI, an influx of histiocytes was observed, while the microabscesses became confluent. From day 3 to day 10 PI, these lesions became enlarged and transformed into typical pyogranulomas with a central necrosis and a peripheral mantle of mononuclear cells composed of macrophages, epithelioid cells and lymphocytes; these histological changes were associated with a bacterial dissemination limited to the superficial lymph nodes. A lymphoid hyperplasia with prominent germinal centers was observed in the draining lymph nodes from day 3 PI. These results illustrate the dual role of granulomatous lesions in chronic bacterial infections: although they limit bacterial dissemination, the granulomas do not impair the persistence of infectious organisms in the host, leading to focal tissue damage.
对接种后十天内羔羊腮腺淋巴结在实验性伪结核棒状杆菌感染期间的组织学反应进行了研究。羔羊通过皮下途径在右眼睑接种一株强毒伪结核棒状杆菌。接种后第1天（PI），在右侧腮腺淋巴结中可见多个主要由多形核（PMN）白细胞浸润的微观急性脓肿。这种大量的PMN浸润与外周血粒细胞增多同时出现。接种后第3天，观察到组织细胞流入，同时微脓肿融合。从接种后第3天到第10天，这些病变扩大并转变为典型的脓性肉芽肿，伴有中央坏死和由巨噬细胞、上皮样细胞和淋巴细胞组成的外周单核细胞层；这些组织学变化与局限于浅表淋巴结的细菌播散有关。从接种后第3天起，在引流淋巴结中观察到具有明显生发中心的淋巴样增生。这些结果说明了肉芽肿性病变在慢性细菌感染中的双重作用：虽然它们限制了细菌播散，但肉芽肿并不损害感染性生物体在宿主体内的持续存在，从而导致局部组织损伤。
