De Clercq Evelien, Devriendt Bert, Yin Lizi, Chiers Koen, Cox Eric, Vanrompay Daisy
Vet Res. 2014 Sep 25;45(1):95. doi: 10.1186/s13567-014-0095-6.
The aim of the present study was to reveal the characteristic features of genital Chlamydia suis infection and re-infection in female pigs by studying the immune response, pathological changes, replication of chlamydial bacteria in the genital tract and excretion of viable bacteria. Pigs were intravaginally infected and re-infected with C. suis strain S45, the type strain of this species. We demonstrated that S45 is pathogenic for the female urogenital tract. Chlamydia replication occurred throughout the urogenital tract, causing inflammation and pathology. Furthermore, genital infection elicited both cellular and humoral immune responses. Compared to the primo-infection of pigs with C. suis, re-infection was characterized by less severe macroscopic lesions and less chlamydial elementary bodies and inclusions in the urogenital tract. This indicates the development of a certain level of protection following the initial infection. Protective immunity against re-infection coincided with higher Chlamydia-specific IgG and IgA antibody titers in sera and vaginal secretions, higher proliferative responses of peripheral blood mononuclear cells (PBMC), higher percentages of blood B lymphocytes, monocytes and CD8⁺ T cells and upregulated production of IFN-γ and IL-10 by PBMC.
本研究的目的是通过研究免疫反应、病理变化、衣原体在生殖道中的复制以及活菌的排泄情况，揭示雌性猪生殖系统猪衣原体感染和再感染的特征。用猪衣原体菌株S45（该物种的模式菌株）对猪进行阴道内感染和再感染。我们证明S45对雌性泌尿生殖道具有致病性。衣原体在整个泌尿生殖道中复制，引发炎症和病理变化。此外，生殖道感染引发了细胞免疫和体液免疫反应。与猪初次感染猪衣原体相比，再感染的特征是宏观病变较轻，泌尿生殖道中的衣原体原体和包涵体较少。这表明初次感染后产生了一定程度的保护作用。针对再感染的保护性免疫与血清和阴道分泌物中较高的衣原体特异性IgG和IgA抗体滴度、外周血单个核细胞（PBMC）较高的增殖反应、血液中较高比例的B淋巴细胞、单核细胞和CD8⁺T细胞以及PBMC中IFN-γ和IL-10的产生上调有关。
