Therapeutic Effect And Its Potential Mechanism Of Anti-Tim3Antibody In Mice With Sepsis

ObjectiveThe aim of this study is to explore the change of immunopathology level in thethymus, spleen, lung and liver tissue in septic mice treated with anti-Tim3antibody andwhether the anti-Tim3antibody improve the survival of mice with sepsis.Methods1. Classic CLP mice models were established according to literature.TwelveC57BL/6mice were randomly divided into sepsis model group (CLP, n=6) and Shamgroup (Sham, n=6). At24h after CLP model surgery, the expression of Tim3onlymphocytes of each group was measured by flow cytometry.2. Forty C57BL/6mice were randomly divided into four groups, i.e., Sham group(Sham, n=10), CLP group (CLP, n=10), Isotype antibody control group (Isotype, n=10),anti-Tim3antibody group (anti-Tim3, n=10). Survival time of mice in each group wasrecorded for7days after CLP challenge.3. Twenty four C57BL/6mice were randomly divided into four groups, i.e., Shamgroup (Sham, n=6), CLP group (CLP, n=6), Isotype control group (Isotype, n=6),anti-Tim3antibody group (anti-Tim3, n=6). Saline, anti-Tim3antibody or Isotype controlantibody were administered immediately after surgery (50ug/150ul), respectively. At24hafter surgery, lung and liver tissue of mice in each group were harvested for pathologicalexamination. Thymus and spleen tissue of mice in each group were harvested for TUNELpathological examination. Thymus and spleen tissue were stained with AV-PI for T cellapoptosis. Plasma TNF-α, IL-10, IL-6and IFN-γ were examined by ELISA. Bacterialclearance rate of blood and peritoneal lavage were determined..Results1. At24h after CLP surgery, The expression of Tim3on CD8+T cells wassignificantly higher in sepsis group than that of sham group(P<0.01).2. Anti-Tim3antibody, saline, or Isotype antibody was given to mice, respectively.It showed that anti-Tim3antibody improved the survival of septic mice, compared withCLP and Isotype group (P<0.01).3.At24h after CLP surgery, the damage of lung and liver tissue was attenuated inanti-Tim3group compared with CLP and Isotype group.Our TUNEL staining resultsindicated that the apoptosis in anti-Tim3group were lower than that of CLP and Isotype group. The proportion T cell apoptosis of thymus and spleen tissue was significantlylower in anti-Tim3group compared with CLP and Isotype group. The expression ofTNF-α, IL-6, and IFN-γ in anti-Tim3group were significantly lower than that of CLPand Isotype group. The expression of IL-10in anti-Tim3group was significantly higherthan that of CLP and Isotype group. Bacterial clearance rate of blood and peritoneallavage was significantly improved in anti-Tim3group compared with CLP and Isotypegroup. the number of Neutrophils of peritoneal lavage in mice from anti-Tim3group wasincreased significantly compared with that CLP and Isotype group (P<0.01).ConclusionThe expression of Tim3on CD8+T cells from spleen increased significantly afterCLP challenge. Anti-Tim3antibody can improve the survival of mice with CLPchallenge.s. Anti-Tim3antibody could inhibit the apoptosis of T cell apoptosis in thymusand spleen, with improvement in abdominal and blood bacterial clearance rate, andregulation the number of neutrophils.