Functional Th1 Cells Are Required for Surgical Adhesion Formation in a Murine Model

Tissue trauma in the peritoneal and pelvic cavities following surgery or bacterial infection results in adhesions that are a debilitating cause of intestinal obstruction, chronic pelvic pain, and infertility in women. We recently demonstrated that CD4+ αβ T cells are essential for development of this process. Using a murine model of experimental adhesion formation, we now demonstrate that adhesion formation is characterized by the selective recruitment of Tim-3+, CCR5+, CXCR3+, IFN-γ+ cells, indicating the presence of a Th1 phenotype. We further demonstrate that adhesion formation is critically dependent on the function of Th1 cells because mice genetically deficient for IFN-γ, T-bet, or treated with Abs to the Th1-selective chemoattractant IL-16 show significantly less adhesion formation than wild-type mice. In addition, disrupting the interaction of the Th1-specific regulatory molecule Tim-3, with its ligand, significantly exacerbates adhesion formation. This enhanced response is associated with increases in the level of neutrophil-attracting chemokines KC and MIP-2, known to play a role in adhesiogenesis. These data demonstrate that the CD4+ T cells orchestrating adhesion formation are of the Th1 phenotype and delineate the central role of T-bet, Tim-3, IFN-γ, and IL-16 in mediating this pathogenic tissue response.