accumulation of ccr4+ ctla-4hi foxp3+cd25hi regulatory t cells in colon adenocarcinomas correlate to reduced activation of conventional t cells积累ccr4 + ctla-4hi foxp3 + cd25hi调节性t细胞在结肠腺癌与传统的t细胞的活化.pdfVIP

+ hi + hi Accumulation of CCR4 CTLA-4 FOXP3 CD25 Regulatory T Cells in Colon Adenocarcinomas Correlate to Reduced Activation of Conventional T Cells 1 1 1 1 ¨ 2 Helena Svensson *, Veronica Olofsson , Samuel Lundin , Chakradhar Yakkala , Stellan Bjorck , Lars ¨ 2 2 ¨ 1 Borjesson , Bengt Gustavsson , Marianne Quiding-Jarbrink ¨ 1 Department of Microbiology and Immunology, Institute of Biomedicine, University of Gothenburg, Goteborg, Sweden, 2 Department of Surgery, Institute of Clinical ¨ Sciences, University of Gothenburg, Goteborg, Sweden Abstract Background: Colorectal cancer usually gives rise to a specific anti-tumor immune response, but for unknown reasons the resulting immunity is not able to clear the tumor. Recruitment of activated effector lymphocytes to the tumor is important for efficient anti-tumor responses, while the presence of regulatory T cells (Treg) down-modulate tumor-specific immunity. We therefore aimed to determine homing mechanisms and activation stage of Treg and effector T cell infiltrating colon tumors compared to cells from the unaffected mucosa in patients suffering from colon adenocarcinoma. Methodology/Principal Findings: Lymphocytes were isolated from unaffected and tumor mucosa from patients with colon adenocarcinoma, and flow cytometry, immunohistochemistry, and quantitative PCR was used to investigate the homing