TISSUE TRANSPLANTATION RECTIONS IN SCHISTOSOME TRANSMITTING SNAILS

异位心脏移植和同种异种心脏移植存活，即， 持续跳动，6个月后植入体腔内 日本血吸虫的主要中间宿主--光滑蜗牛 新大陆的曼苏尼。然而，来自其他属的异种移植物，除了 那些来自三卷海鞘的病毒被迅速摧毁，而不是 捐赠者与受赠者之间的分类距离(以及可能的系统发育)。 尽管这些结果加深了我们对 在软体动物的组织移植方面，仍然存在几个问题 细胞对移植物的反应的性质，非我的类型 受体血细胞识别的决定因素，以及 供受者系统发育距离与异种移植命运的关系。 因此，细胞对同种异体移植物的反应将与 那些反对同种异体的人。下一步，将试图改变命运 通过改变或遮盖细胞表面来治疗异体移植和异种移植 分子。辨别生理上的不适和 免疫排斥是异种移植死亡的机制，琼脂糖凝胶- 微囊化的异种移植物将被植入。最后，心脏移植来自 将开展与Helisoma密切相关的两个属的研究 进一步阐明H.trivolvis和H.trivolvis的系统发育关系 平纹拟青霉B.blomrata.除了先前的组织学技术之外 将开发一种移植物破坏的体外模型，并 肌动蛋白特异性染色方法将用于评估移植物的命运。

Heterotopic heart allografts and congeneric xenografts survive, i.e., continue to beat, for 6 months when implanted into the body cavity of the snail Biomphalaria glabrata, the main intermediate host of Schistosoma mansoni in the New World. However, xenografts from other genera, except those from Helisoma trivolvis, are rapidly destroyed, regardless of donor-recipient taxonomic (and presumably phylogenetic) distance. Although these results have enhanced our understanding of the fate of tissue transplants in molluscs, several questions remain with respect to the nature of the cellular response against grafts, the types of nonself determinants recognized by the recipient's hemocytes, and the relationship of donor-recipient phylogenetic distance and xenograft fate. Consequently, cellular responses against allografts will be compared to those against isografts. Next, an attempt will be made to alter the fate of allografts and xenografts by altering or masking cell surface molecules. To discern between physiological unsuitability and immunological rejection as the mechanism of xenograft death, agarose- encapsulated xenografts will be implanted. Finally, heart implants from two genera which are closely related to Helisoma will be carried out to further elucidate the phylogenetic relationship between H. trivolvis and B. glabrata. In addition to the histological techniques previously employed, an in vitro model of graft destruction will be developed, and an actin-specific staining method will be used to assess graft fate.