Protective immunity induced by recombinant protein CPSIT_p8 of Chlamydia psittaci
Protective immunity induced by recombinant protein CPSIT_p8 of Chlamydia psittaci
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鹦鹉热衣原体重组蛋白CPSIT_p8诱导的保护性免疫
DOI：
10.1007/s00253-016-7494-8
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发表时间：
2016-07-01
影响因子：
5
通讯作者：
Wu, Yimou
中科院分区：
文献类型：
--
作者：
Liang, Mingxing;Wen, Yating;Wu, Yimou
鹦鹉热衣原体是一种具有广泛宿主范围的人畜共患病原体，可导致人类严重的呼吸道和全身性疾病。目前，针对C.没有鹦鹉热感染的资料。衣原体质粒是一种重要的毒力因子，其编码的质粒蛋白在衣原体感染和相应的免疫应答中起重要作用。在这项研究中，我们评估了质粒蛋白疫苗预防C。鹦鹉热肺部感染的小鼠模型。用纯化的重组CPSIT_p8蛋白免疫BALB/c小鼠，间隔2周，共免疫3次，然后感染C.鹦鹉免疫显著降低了感染小鼠肺部的衣原体负荷，导致IFN-γ水平降低，并减轻了炎症程度。体内或体外中和C.用从免疫小鼠收集的血清处理鹦鹉热并不减少活的C.这表明CPSIT_p8特异性抗体不具有中和能力。此外，使用小鼠抗CPSIT_p8抗体的共聚焦荧光显微镜显示CPSIT_p8定位于C.鹦鹉热6BC感染的细胞。我们的结果表明，CPSIT_p8蛋白诱导了针对C. psittaci在小鼠中的表达，代表了预防C.鹦鹉热感染
Chlamydia psittaci is a zoonotic pathogen with a broad host range that can lead to severe respiratory and systemic disease in humans. Currently, an effective commercial vaccine against C. psittaci infection is not available. The chlamydial plasmid is an important virulence factor and encodes plasmid proteins that play important roles in chlamydial infection and the corresponding immune response. In this study, we assessed the efficacy of vaccination with plasmid proteins at preventing C. psittaci lung infection in a murine model. BALB/c mice were immunized intraperitoneally, three times at 2-week intervals, with purified recombinant CPSIT_p8 protein and then infected with C. psittaci. Immunization significantly decreased chlamydial load in the lungs of infected mice, resulted in a lower level of IFN-γ, and reduced the extent of inflammation. In vivo or in vitro neutralization of C. psittaci with sera collected from immunized mice did not reduce the amount of viable C. psittaci in the lungs of mice, indicating that CPSIT_p8-specific antibodies do not have neutralizing capacity. Furthermore, confocal fluorescence microscopy using a mouse anti-CPSIT_p8 antibody revealed that CPSIT_p8 was localized inside the inclusion of C. psittaci 6BC-infected cells. Our results demonstrate that CPSIT_p8 protein induces significant protective immunity against challenge with C. psittaci in mice and represents a promising new vaccine candidate for the prevention of C. psittaci infection.