Kapatais-Zoumbos K, Chandler D K, Barile M F
Infect Immun. 1985 Mar;47(3):704-9. doi: 10.1128/iai.47.3.704-709.1985.
Because immunoglobulin A (IgA) is the predominant immunoglobulin at mucosal surfaces, IgA proteases produced by pathogenic bacteria are considered potential virulence factors for organisms that cause disease or gain entry at mucous membranes. To determine the role of IgA protease in the pathogenicity of mycoplasmal disease, a variety of human and animal mycoplasma and ureaplasma species were examined for IgA protease activity with human, murine, porcine, and canine IgA. None of the mycoplasma species examined showed detectable IgA protease activity with any of the IgAs tested. Twenty-eight strains of Ureaplasma urealyticum isolated from human urogenital tissues cleaved human IgA1, but no cleavage of human IgA2 or murine, porcine, or canine IgA was observed. Ureaplasmas isolated from nonhuman hosts (feline, canine, avian, and bovine [Ureaplasma diversum]) did not cleave human IgA1. Two strains of canine ureaplasmas were able to cleave canine IgA, but not murine IgA. Thus, ureaplasmas from other species can produce IgA protease, but the specificity of the enzyme was restricted to the IgA of the appropriate host. This finding suggests that IgA proteases could play a role in the selective host specificity of mucosal pathogens.
由于免疫球蛋白A（IgA）是黏膜表面的主要免疫球蛋白，病原菌产生的IgA蛋白酶被认为是那些在黏膜处引发疾病或侵入机体的微生物的潜在致病因素。为了确定IgA蛋白酶在支原体疾病致病性中的作用，研究人员使用人、鼠、猪和犬的IgA检测了多种人和动物支原体及脲原体的IgA蛋白酶活性。在所检测的支原体物种中，没有任何一种对所测试的任何一种IgA表现出可检测到的IgA蛋白酶活性。从人泌尿生殖组织分离出的28株解脲脲原体可切割人IgA1，但未观察到对人IgA2或鼠、猪或犬IgA的切割。从非人类宿主（猫、犬、禽类和牛[差异脲原体]）分离出的脲原体不能切割人IgA1。两株犬脲原体能够切割犬IgA，但不能切割鼠IgA。因此，来自其他物种的脲原体可产生IgA蛋白酶，但其酶的特异性仅限于相应宿主的IgA。这一发现表明，IgA蛋白酶可能在黏膜病原体的选择性宿主特异性中发挥作用。
