Black K P, Fultz P N, Girard M, Jackson S
Department of Microbiology, University of Alabama at Birmingham, 35294-2170, USA.
AIDS Res Hum Retroviruses. 1997 Oct 10;13(15):1263-72. doi: 10.1089/aid.1997.13.1263.
HIV infection in humans causes various aberrancies in both the cellular and humoral immune systems, including functional abnormalities of B lymphocytes. In many instances, dysfunction occurs in the regulation of serum IgA, resulting in elevated concentrations of this immunoglobulin isotype. To determine whether HIV-1-infected chimpanzees develop IgA abnormalities similar to those observed in humans, we quantified total IgA, IgG, and IgM levels in sera collected longitudinally from six HIV-infected chimpanzees and one uninfected control animal. In comparison to immunoglobulin levels in the uninfected animal, two of the six infected chimpanzees exhibited increases in serum immunoglobulins following infection with HIV. Two other infected animals showed a marked decrease in the three isotypes within 10 months of exposure to HIV, followed by a return to baseline levels. The remaining two HIV-infected chimpanzees displayed serum immunoglobulin levels that paralleled the baseline levels and did not show great deviation over a period of 20 to 45 months postinfection. ELISA analyses of the IgA subclasses revealed possible abnormalities of the IgA2 subclass within the two animals that did not display irregular IgA, IgG, or IgM responses to HIV-1. Specific IgG, IgA, IgA1, and IgA2 antibodies to HIV antigens were detected by an enzyme immunoassay (EIA) kit and by Western blot analysis with IgA, IgA1, and IgA2 antibodies directed against the env, gag, and pol gene products. Because IgG can mask the detection of HIV-specific IgA antibodies in infected humans, Western blots and EIAs were also performed on IgG-depleted chimpanzee sera. The results demonstrated that in some instances, IgA reactivity against HIV antigens can be enhanced on removal of IgG. This study indicates that HIV-1 is capable of inducing abnormalities in serum IgA expression in chimpanzees. These results might further understanding of how HIV affects humoral responses in infected humans.
人类感染HIV会导致细胞免疫系统和体液免疫系统出现各种异常，包括B淋巴细胞的功能异常。在许多情况下，血清IgA的调节功能会出现障碍，导致这种免疫球蛋白亚型的浓度升高。为了确定感染HIV-1的黑猩猩是否会出现与人类相似的IgA异常，我们对6只感染HIV的黑猩猩和1只未感染的对照动物纵向采集的血清中的总IgA、IgG和IgM水平进行了定量分析。与未感染动物的免疫球蛋白水平相比，6只感染黑猩猩中有2只在感染HIV后血清免疫球蛋白水平升高。另外2只感染动物在接触HIV后10个月内三种亚型均显著下降，随后又恢复到基线水平。其余2只感染HIV的黑猩猩血清免疫球蛋白水平与基线水平相当，在感染后20至45个月内未出现明显偏差。对IgA亚类的ELISA分析显示，在两只对HIV-1未表现出不规则IgA、IgG或IgM反应的动物中，IgA2亚类可能存在异常。通过酶免疫分析（EIA）试剂盒以及使用针对env、gag和pol基因产物的IgA、IgA1和IgA2抗体进行的蛋白质印迹分析，检测到了针对HIV抗原的特异性IgG、IgA、IgA1和IgA2抗体。由于IgG会掩盖感染人类中HIV特异性IgA抗体的检测，因此还对去除IgG的黑猩猩血清进行了蛋白质印迹和EIA检测。结果表明，在某些情况下，去除IgG后针对HIV抗原的IgA反应性会增强。这项研究表明，HIV-1能够在黑猩猩中诱导血清IgA表达异常。这些结果可能会进一步加深我们对HIV如何影响感染人类体液反应的理解。
