目的 探讨多房棘球蚴感染对小鼠腹腔ST2⁺ T细胞亚群功能及其免疫检查点分子表达的影响。 方法 11只BALB/c小鼠随机分为感染组（5只）、对照组（6只）。感染组每鼠经肝门静脉接种4 000个多房棘球蚴原头节，对照组注射等量的生理盐水。感染24周后小鼠腹腔内注入RPMI 1640，取腹腔内液体，离心后收集淋巴细胞，采用流式细胞术筛选小鼠腹腔不同T细胞亚群，检测生长刺激表达基因2蛋白（ST2）的表达变化，比较不同ST2⁺ T细胞亚群功能和表达免疫检查点分子杀伤细胞凝集素样受体G1（KLRG1）、淋巴细胞激活基因-3（LAG3）和程序性死亡受体-1（PD-1）的细胞比例与绝对数，及分泌细胞因子γ干扰素（IFN-γ）、白细胞介素4（IL-4)和IL-17A的细胞比例与绝对数。采用SPSS 25.0 软件进行统计学分析，采用独立样本t检验。 结果 感染后24周，感染组小鼠腹腔内可见囊泡状或实体病灶，ST2⁺CD4⁺ T细胞绝对数为（5.06 ± 3.06）× 10⁴，记忆ST2⁺CD4⁺ T细胞绝对数为（4.66 ± 3.18）× 10⁴，均高于对照组的（3.31 ± 2.77）× 10³和（3.27 ± 2.77）× 10³（t = 3.442、3.035，均P < 0.05）；且感染组小鼠腹腔记忆ST2⁺CD4⁺ T细胞比例为（22.78 ± 6.05）%，绝对数为（4.66 ± 3.18）× 10⁴，均高于非记忆ST2⁺CD4⁺ T细胞比例[（6.68 ± 1.25）%]和绝对数[（3.88 ± 5.20）× 10³]（t = 5.830、2.962，P < 0.01、 0.05）；感染组小鼠腹腔记忆ST2⁺CD8⁺ T细胞比例为（7.03 ± 1.09）%，高于非记忆ST2⁺CD8⁺ T细胞的（4.10 ± 1.57）%（t = 3.417，P < 0.01）。感染小鼠中表达KLRG1、LAG3和PD-1的记忆ST2⁺CD4⁺ T细胞绝对数分别为（2.77 ± 1.41）× 10³、（5.52 ± 3.95）× 10³、（6.59 ± 3.75）× 10³，均高于对照组的（3.66 ± 6.42）× 10²、（1.67 ± 0.72）× 10²、（1.69 ± 1.49）× 10³（t = 3.760、3.356、2.956，P < 0.01、0.05、0.05）。感染组小鼠分泌IFN-γ的记忆ST2⁺CD4⁺ T、ST2⁺CD8⁺ T细胞比例为（5.48 ± 1.33）%和（16.24 ± 4.08）%，均低于对照组的（14.82 ± 3.04）%和（44.70 ± 5.31）%（t = -6.325、-9.786，均P < 0.01）；感染组小鼠分泌IL-4的记忆ST2⁺CD8⁺ T细胞比例为（13.10 ± 3.60）%，高于对照组的（4.59 ± 0.36）%（t = 5.264，P < 0.01）。 结论 多房棘球蚴感染小鼠腹腔T细胞和记忆T细胞表面ST2表达上调，且表达记忆ST2⁺ T细胞KLRG1、LAG3和PD-1分子的比例上调伴随IFN-γ分泌能力减弱，提示记忆ST2⁺ T细胞存在免疫功能耗竭。

Objective To investigate the effect of Echinococcus multilocularis infection on the function of ST2⁺ T cell subsets and the expression of immune checkpoint molecules in the abdominal cavity of mice. Methods Eleven BALB/c mice were randomly divided into the infection group (5) and control group (6). Each mouse in the infection group was inoculated with 4 000 E. multilocularis protoscoleces via the hepatic portal vein, and the control group was injected with the same amount of normal saline. After 24 weeks of infection, RPMI 1640 was injected intraperitoneally into the mice to collect the intraperitoneal fluid, which was centrifuged to harvest lymphocytes. Flow cytometry was used to screen different T cell subsets in mouse abdominal cavity, detect the expression change of growth stimulating gene 2 protein (ST2), compare different ST2⁺ T cell subsets’ functions and the proportion and the absolute number of cells which express molecular killer cell agglutinin like receptor G1 (KLRG1), lymphocyte activating gene 3 (LAG3) and programmed death receptor 1 (PD-1), and the cells which secrete cytokines interferon-γ (IFN-γ）, interleukin-4 (IL-4) and IL-17A. SPSS 25.0 software was used for statistical analysis, and independent sample t-test was used. Results At 24 weeks after infection, cystic or solid lesions were found in the abdominal cavity of mice in the infection group, and the absolute number of ST2⁺CD4⁺ T cells was (5.06 ± 3.06) × 10⁴, the absolute number of memory ST2⁺CD4⁺ T cells is (4.66 ± 3.18) × 10⁴, higher than that of the control group (3.31 ± 2.77) × 10³ and (3.27 ± 2.77) × 10³ (t = 3.442, 3.035; P < 0.05). The percentage of ST2⁺CD4⁺ T cells in the abdominal cavity of the infected mice was (22.78 ± 6.05)%, and the absolute number was (4.66 ± 3.18) × 10⁴, both higher than the proportion and the absolute number of non-memory ST2⁺CD4⁺ T cells[(6.68 ± 1.25)% and (3.88 ± 5.20) × 10³ ] (t = 5.830, 2.962; P < 0.01, 0.05). The percentage of ST2⁺CD8⁺ T cells in the abdominal cavity of infected mice was (7.03 ± 1.09)%, higher than that of non-memory ST2⁺CD8⁺ T cells (4.10 ± 1.57)% (t = 3.417, P < 0.01). The absolute number of memory ST2⁺CD4⁺ T cells expressing KLRG1, LAG3 and PD-1 in the infection group was (2.77 ± 1.41) × 10³, (5.52 ± 3.95) × 10³, (6.59 ± 3.75) × 10³, higher than that of the control group (3.66 ± 6.42) × 10², (1.67 ± 0.72) × 10², (1.69 ± 1.49) × 10³ (t = 3.760, 3.356, 2.956; P < 0.01, 0.05, 0.05). IFN-γ is secreted by ST2⁺CD4⁺ T and ST2⁺CD8⁺ T cells in the abdominal cavity of mice in the infection group. The proportion was (5.48 ± 1.33)% and (16.24 ± 4.08)%, lower than (14.82 ± 3.04)% and (44.70 ± 5.31)% in the control group (t = -6.325, -9.786; P < 0.01). The proportion of memory ST2⁺CD8⁺ T cells secreting IL-4 in infected mice was (13.10 ± 3.60)%, higher than that in control mice (4.59 ± 0.36)% (t = 5.264, P < 0.01). Conclusion The expression of ST2 on the surface of peritoneal T cells and memory T cells was up-regulated in E. multilocularis-infected mice, and the percentage of KLRG1, LAG3 and PD-1 molecules were upregulated on memory ST2⁺ T cells with a concomitant decrease in IFN-γ secretion capacity, suggesting the memory ST2⁺ T cells showing immune function exhaustion.