MHC variation, multiple simultaneous infections and physiological condition in the subterranean rodent Ctenomys talarum.
MHC variation, multiple simultaneous infections and physiological condition in the subterranean rodent Ctenomys talarum.
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地下啮齿动物 Ctenomys talarum 的 MHC 变异、多重同时感染和生理状况。
DOI：
10.1016/j.meegid.2011.03.016
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发表时间：
2011
期刊：
影响因子：
--
通讯作者：
E. Lacey
中科院分区：
文献类型：
--
作者：
A. Cutrera;R. Zenuto;E. Lacey
寄生虫和病原体可以在塑造宿主种群的遗传多样性方面发挥重要作用，特别是在与宿主免疫反应相关的基因方面。为了在脊椎动物自然种群中探索这种关系，我们将地下啮齿动物ctenomys talarum（talas tuco-tuco）的主要组织相容性复合体（MHC）变异表征为寄生虫负荷和对新抗原进行适应性免疫反应能力的功能。具体来说，我们量化了MHC II类DRB位点的基因型多样性，这与(1)多属寄生虫感染的自然变异（MHC基因的潜在选择因子）和(2)绵羊红细胞注射后产生的抗体（免疫能力的一种衡量标准）有关。使用共惯性多变量统计分析数据，并结合个体状况（血细胞比容、白细胞谱、体重）和寄生虫暴露风险（捕获季节、性别）的流行病学指标。在研究人群中，DRB杂合子明显过量。共惯性分析显示，特异性DRB等位基因与寄生虫载量和针对绵羊红细胞的体液免疫反应强度之间存在显著关联。特异性DRB氨基酸序列的存在似乎比DRB位点的杂合性与寄生虫负荷和对新抗原的反应有更强的相关性。这些数据表明，寄生虫驱动的平衡选择在维持c自然种群中MHC变异方面发挥了作用。talarum。同时，这些发现强调了使用不同参数来研究同时面临多种免疫挑战的自由生活动物的生理条件、免疫能力和MHC多样性之间相互作用的重要性。
Parasites and pathogens can play a significant role in shaping the genetic diversity of host populations, particularly at genes associated with host immune response. To explore this relationship in a natural population of vertebrates, we characterized Major Histocompatibility Complex (MHC) variation in the subterranean rodentCtenomys talarum(the talas tuco-tuco) as a function of parasite load and ability to mount an adaptive immune response against a novel antigen. Specifically, we quantified genotypic diversity at the MHC class II DRB locus in relation to (1) natural variation in infection by multiple genera of parasites (potential agents of selection on MHC genes) and (2) antibody production in response to injection with sheep red blood cells (a measure of immunocompetence). Data were analyzed using co-inertia multivariate statistics, with epidemiological proxies for individual condition (hematocrit, leukocyte profile, body weight) and risk of parasite exposure (season of capture, sex). A significant excess of DRB heterozygotes was evident in the study population. Co-inertia analyses revealed significant associations between specific DRB alleles and both parasite load and intensity of humoral immune response against sheep red blood cells. The presence of specific DRB aminoacid sequences appeared to be more strongly associated with parasite load and response to a novel antigen than was heterozygosity at the DRB locus. These data suggest a role for parasite-driven balancing selection in maintaining MHC variation in natural populations ofC. talarum.At the same time, these findings underscore the importance of using diverse parameters to study interactions among physiological conditions, immunocompetence, and MHC diversity in free-living animals that are confronted with multiple simultaneous immune challenges.
DOI：
10.1073/pnas.97.8.4204
发表时间：
2000-04-11
影响因子：
11.1
作者：
Sousa, AO;Mazzaccaro, RJ;Bloom, BR
通讯作者：
Bloom, BR