Silva J R, Mendes E G, Mariano M
Departmento de Histologia e Embriologia, Instituto de Ciências Biomedicas, Cidade Universitária, São Paulo, Brazil.
J Invertebr Pathol. 1995 Mar;65(2):147-51. doi: 10.1006/jipa.1995.1022.
The existence of phagocytes in the Amphioxus is a matter of debate since early studies of Metchnikoff, who could not induce inflammation in this animal. To reinvestigate this important phenomenon, we sectioned the distal portion of the animal and analyzed, by morphological methods, the presence of phagocytes in the wound. The analysis of the wound by optical and electron microscopy did not detect cells with morphological characteristics of phagocytes in it. The wound is completely covered by the external cuticle of the animal 24 hr after the lesion was made. A second section of the animal leads to abnormal healing of the lesion. The insertion of a surgical silk thread in the muscle of the animals results--after 13 days--in a collection of cells surrounding the foreign body. The ultrastructural analysis of these cells showed they are endothelial cells rather than specialized phagocytes. Yet, the Amphioxus is able to mount an allograph rejection when the animals are tied together by suture. This intriguing capacity of the Amphioxus to cope with tissue healing, infection, and other pathologies without phagocytes is discussed.
自梅契尼科夫早期研究以来，文昌鱼中吞噬细胞的存在一直存在争议，他无法在这种动物中诱发炎症。为了重新研究这一重要现象，我们对动物的远端部分进行了切片，并通过形态学方法分析了伤口中吞噬细胞的存在情况。通过光学显微镜和电子显微镜对伤口的分析未在其中检测到具有吞噬细胞形态特征的细胞。在损伤形成24小时后，伤口被动物的外表皮完全覆盖。对动物的第二次切片导致损伤愈合异常。在动物肌肉中插入手术丝线，13天后会导致异物周围出现细胞聚集。对这些细胞的超微结构分析表明它们是内皮细胞而非特化的吞噬细胞。然而，当动物通过缝合绑在一起时，文昌鱼能够产生异体排斥反应。本文讨论了文昌鱼在没有吞噬细胞的情况下应对组织愈合、感染和其他病理状况的这种有趣能力。
