Rasmussen K R, Healey M C, Cheng L, Yang S
Department of Animal, Dairy and Veterinary Sciences, Utah State University, Logan 84322-5600, USA.
J Parasitol. 1995 Jun;81(3):429-33.
Cryptosporidiosis is a diarrheal disease in humans and other animals caused by the coccidian parasite, Cryptosporidium parvum. This study was undertaken to determine the effectiveness of dehydroepiandrosterone (DHEA) in reducing C. parvum infections in immunosuppressed adult C57BL/6N mice and to identify the immunomodulatory effects of DHEA that result in increased resistance to cryptosporidiosis. Dexamethasone-immunosuppressed mice were readily infected with C. parvum following orogastric intubation with 10(6) oocysts/mouse. DHEA treatment of these mice significantly reduced (P < 0.01) both fecal oocyst shedding and parasite colonization of the ilea. Immunosuppressed mice treated with DHEA had more splenic total T cells, CD4+ T cells, and CD8+ T cells than immunosuppressed mice that were not treated, but the differences were not always significant. Moreover, nonimmunosuppressed mice treated with DHEA had significantly more (P < 0.05) splenic total T cells, CD4+ T cells, and total B cells than nonimmunosuppressed mice that did not receive DHEA. Of particular interest was the significantly larger (P < 0.05) number of CD8+ T cells in immunosuppressed, C. parvum-infected, DHEA-treated mice compared with the same mice that were not treated. Up-regulation of the immune system by exogenous DHEA may be useful in the treatment and palliation of cryptosporidiosis.
隐孢子虫病是由球虫寄生虫微小隐孢子虫引起的人类和其他动物的腹泻病。本研究旨在确定脱氢表雄酮（DHEA）在降低免疫抑制的成年C57BL/6N小鼠微小隐孢子虫感染方面的有效性，并确定DHEA导致对隐孢子虫病抵抗力增强的免疫调节作用。用10(6)个卵囊/小鼠经口胃插管后，地塞米松免疫抑制的小鼠很容易感染微小隐孢子虫。对这些小鼠进行DHEA治疗可显著降低（P < 0.01）粪便中卵囊排出量和回肠中的寄生虫定植。接受DHEA治疗的免疫抑制小鼠比未接受治疗的免疫抑制小鼠有更多的脾脏总T细胞、CD4+ T细胞和CD8+ T细胞，但差异并不总是显著。此外，接受DHEA治疗的非免疫抑制小鼠比未接受DHEA的非免疫抑制小鼠有显著更多（P < 0.05）的脾脏总T细胞、CD4+ T细胞和总B细胞。特别值得关注的是，与未接受治疗的相同小鼠相比，接受DHEA治疗的免疫抑制、感染微小隐孢子虫的小鼠中CD8+ T细胞数量显著更多（P < 0.05）。外源性DHEA对免疫系统的上调可能有助于隐孢子虫病的治疗和缓解。
