Plasma resistance factors in Biomphalaria glabrata

描述：导致非易感性感染的机制 曼氏血吸虫在光滑生物钉螺中的分布情况尚不清楚。 不敏感的最有可能的解释是免疫抵抗， 可能涉及(1)识别寄生虫为非我和/或未能 识别寄生虫为自身，(2)对寄生虫产生细胞毒反应 孢子囊，以及(3)抵抗或对抗寄生虫免疫抑制 可能干扰(1)或(2)的因素。包括细胞和体液 机制(可能独立起作用或与血细胞协同作用)一直是 与孢子囊破坏有关。这种抵抗力可以转移到 不敏感的蜗牛既过继，通过移植的造血细胞 造血细胞生成器官(APO)或被动，通过注射血浆。虽然 被动转会被描述在16年前，它一直保留着 未被研究，尽管有可能阐明体液机制 血吸虫抗药性。初步研究证实， 来自其他类型抗药性蜗牛的血浆中的抗性因子，并具有 提供了有关影响持续时间、孢子囊命运的新信息 在被动转移阻力的蜗牛中，以及阻力 因素分子量和来源。这项提议试图进一步描述 被动地将抗性转移给曼氏血吸虫并鉴定相关的 血浆阻力系数(S)。

DESCRIPTION: Mechanisms responsible for no susceptibility to infection with Schistosoma mansoni in Biomphalaria glabrata snails are not well understood. The most likely explanation for non-susceptibility is immunological resistance, possibly involving (1) recognizing the parasite as non-self and/or failing to recognize the parasite as self, (2) mounting a cytotoxic response against the sporocyst, as well as (3) withstanding or countering parasite immunosuppressive factors, which could interfere with (1) or (2). Both cellular and humoral mechanisms (which may act independently or in concert with hemocytes) have been implicated in sporocyst destruction. This resistance can be transferred to non-susceptible snails both adoptively, by transplants of the hematopoietic amebocyte-producing organ (APO) or passively, by injections of plasma. Although passive transfer was described over 16 years ago, it has remained uninvestigated, despite the potential for elucidating humoral mechanisms of schistosome resistance. Preliminary studies have confirmed the presence of resistance factor in plasma from additional types of resistant snails, and have provided new information on the duration of the effect, the fate of sporocysts in snails with passively transferred resistance, as well as the resistance factor molecular weight and source. This proposal seeks to further characterize passively transferred resistance to S. mansoni and to identify the relevant plasma resistance factor(s).