Coccidiosis is an intestinal parasitic disease that is caused by Eimeria tenella and other species, and it seriously restricts the economic development of the broiler breeding industry. In this study, a recombinant Lactobacillus plantarum with an invasive effect was constructed, and it expressed the TA4-AMA1 protein of E. tenella. After oral immunization with recombinant L. plantarum, specific humoral and mucosal immune levels were measured by indirect ELISA, and the differentiation of T cells was analysed by flow cytometry. After challenge with sporulated oocysts, the body weight, oocyst shedding and cecum lesions of the chicken were evaluated. The results indicated that chickens immunized with recombinant invasive L. plantarum produced higher levels of specific antibodies in the serum than did the non-immunized controls, and the secretory IgA (sIgA) levels were increased in the intestinal washes compared to those of the controls (P < 0.05). Flow cytometry showed that recombinant invasive L. plantarum significantly stimulated T cell differentiation compared to the PBS group (P < 0.01, P < 0.001), and a higher proportion of CD4⁺ and CD8⁺ T cells were detected in peripheral blood. Moreover, the lesion scores and histopathological caecum sections showed that immunizing chickens with recombinant invasive L. plantarum can significantly relieve pathological damage in the cecum (P < 0.01), and the relative body weight gain was 89.64 %, which was higher than the 79.83 % gain in the chickens immunized with non-invasive L. plantarum. After the challenge, faeces from ten chickens in each group were collected between 4 and 7 days, and the oocysts per gram (OPG) was determined by the McMaster technique. The data indicated that oocysts in the faeces of chickens immunized with the recombinant invasive L. plantarum were significantly lower than those of the controls (P < 0.01). The results suggest that recombinant invasive L. plantarum effectively activated immune responses against E. tenella infection and can be used as a candidate vaccine against E. tenella infection.

球虫病是一种由艾美球虫和其他物种引起的肠道寄生虫病，严重限制了肉鸡育种业的经济发展。在这项研究中，构建了具有侵袭作用的重组植物乳杆菌，并表达了大肠杆菌的TA4-AMA1蛋白。用重组植物乳杆菌口服免疫后，通过间接ELISA检测特定的体液和粘膜免疫水平，并通过流式细胞术分析T细胞的分化。用带孢子的卵囊攻击后，评估鸡的体重，卵囊脱落和盲肠病变。结果表明，鸡用重组侵袭性免疫与未免疫的对照组相比，植物乳杆菌在血清中产生的特异性抗体水平更高，并且与对照组相比，肠道洗涤液中的分泌型IgA（sIgA）水平有所提高（P <0.05）。流式细胞仪显示，与PBS组相比，重组侵入性植物乳杆菌显着刺激T细胞分化（P <0.01，P <0.001），并且在外周血中检测到更高比例的CD4 ⁺和CD8 ⁺ T细胞。此外，病变分数和组织病理学盲肠切片显示用重组侵入性植物乳杆菌对鸡进行免疫可以显着缓解盲肠的病理损伤（P <0.01），相对体重增加为89.64％，高于无创植物乳杆菌免疫的鸡的体重增加79.83％。攻击后，在4至7天之间收集每组10只鸡的粪便，并通过McMaster技术确定每克卵囊（OPG）。数据表明，用重组侵入性植物乳杆菌免疫的鸡粪便中的卵囊明显低于对照组（P <0.01）。结果表明，重组侵入性植物乳杆菌可有效激活针对大肠杆菌的免疫反应，并可作为抗大肠杆菌的候选疫苗大肠埃希菌感染。