Role of peripheral blood lymphocyte subsets in echinococcosis-induced sensitization in mice / 中华微生物学和免疫学杂志

ABSTRACT

Objective:To establish a BALB/c mouse model of Echinococcus granulosus allergy and investigate the role of lymphocyte subsets in Echinococcus granulosus-induced sensitization. Methods:Echinococcus granulosus was isolated from the liver of sheep naturally infected with Echinococcus granulosus and cultured for 40 d. BALB/c mice were intraperitoneally injected with 50 microcapsules and sensitized by intraperitoneal injection of 0.1 ml/10 g of larval Echinococcus granulosus capsule six months after infection. According to the symptom scores 1 h after sensitization, these mice were divided into two groups non-sensitized group ( n=6) and sensitized group ( n=6). The mice ( n=6) in control group were injected with sterile saline. Blood sample was collected from the angular vein of each mouse. Flow cytometry was used to detect B cells, NK cells and CD3 +/CD4 +/CD8 + T cells. Cytometric bead array was used to measure IL-4, IL-6 and IL-13. Results:The percentage of B cells was significantly higher in the non-sensitized group than in the control group ( P<0.001), but no significant difference was observed between the sensitized group and the control group. Compared with the non-sensitized group, the percentage of B cells in the sensitized group decreased significantly ( P<0.01). Compared with the control group, the percentages of NK cells in the non-sensitized group and the sensitized group decreased significantly ( P<0.001 and P<0.01). Compared with the non-sensitized group, the percentage of NK cells in the sensitized group increased significantly ( P<0.05). Compared with the control group, the percentage of CD3 + and CD4 + T cells in the non-sensitized group decreased significantly ( P<0.05), while the percentage of CD8 + T cells increased significantly ( P<0.01). Compared with the control group, the percentage of CD3 + and CD4 + T cells in the sensitized group increased significantly ( P<0.05 and P<0.001), while no significant change in the percentage of CD8 + T cells was detected. Compared with the non-sensitized group, the percentage of CD3 + and CD4 + T cells in the sensitized group increased significantly ( P<0.05), while the percentage of CD8 + T cells decreased significantly ( P<0.01). The levels of IL-4, IL-6 and IL-13 were significantly higher in the non-sensitized group than in the control group ( P<0.001). Compared with the control group, the sensitized group showed increased IL-4 ( P>0.05), significantly increased IL-6 ( P<0.01) and decreased IL-13 ( P>0.05). The levels of IL-4, IL-6 and IL-13 in the sensitized group were significantly lower than those in the non-sensitized group ( P<0.001). Conclusions:The BALB/c mouse model of allergy induced by larval Echinococcus granulosus was successfully established. This study proved that the humoral immune response induced by Th2 cells played an important role in Echinococcus granulosus-induced sensitization, which provides an important scientific basis for establishing a prevention and treatment strategy for patients with anaphylactic shock caused by extravasation of Echinococcus granulosus fluid.