Treg cells inhibits the progression of middle ear inflammation in mice with chronic otitis media
Objective To explore the relationship between Treg cells and inflammation development in chronic otitis media(COM)mice.Methods COM mouse model was induced by intraperitoneal injection of non-typeable Haemophilus influenzae(NTHi)and blocking of eustachian tube(ET)in the middle ear,and healthy BALB/c mice were used as control group.Middle ear effusion(MEE)and middle ear mucosal(MEM)tissue of mice were collected at day 3,14,28 and 56 after modeling.The pathological changes of MEM tissue were detected by hematoxylin-eosin(HE)staining.The CD4+and Foxp3+T cell levels were evaluated by immunohisto-chemical staining.The levels of tumor necrosis factor α(TNF-α),interleukin-1 β(IL-1 β),IL-10 and transforming growth factor(TGF-β)in MEE and MEM tissue of mice were detected by enzyme-linked immunosorbent assay(ELISA)and Western blot,respectively.The proportion of CD4+CD25+Foxp3+cells was analyzed by flow cytometry.COM model mice were divided into PBS group and anti-CD25 group.The mice in anti-CD25 group were intraperitoneally injected with anti-CD25 mAb to simulate Treg depletion in vivo,and the mice in PBS group were intraperitoneally injected with the same amount of PBS solution.The MEE,MEM tissue,spleen and cervical lymph nodes of the mice were collected at day 56.The proportion of CD4+CD25+Foxp3+cells in spleen,cervical lymph nodes and MEM tissue,and the level of inflammatory factors in MEM and the level of bacteria in MEE were detected and analyzed.Results HE results showed that MEM of mice in control group was normal,while the inflammatory cell infiltration occurred in MEM tissue of mice in model group,and the numbers of bacteria and inflammatory cells and the thickness of MEM were increased(P＜0.05).Compared with control group,the proportion of CD4+CD25+Foxp3+cells in MEM tissues of mice was increased in model group(P＜0.05),and the levels of inflammatory factors IL-1 β,TNF-α,IL-10 and TGF-β in MEE and MEM tissues were increased(P＜0.01).Compared with PBS group,the proportion of CD4+CD25+Foxp3+cells in MEM tissue,spleen and neck lymph nodes of mice were decreased in anti-CD25 group(P＜0.05),and the bacterial count in MEE and the levels of inflammatory factors IL-1β,TNF-α,IL-10 and TGF-β in MEM were decreased(P＜0.01).Conclusion Treg cells play an important role in the maintenance of inflammation balance in chronic otitis media,inhibit the progression of inflammation,but excessive Treg cells inhibit the host's clearance of bacteria.
万方数据
维普
