High level of T-cell infiltration in colorectal carcinomas (CRCs) is a good prognostic indicator, but the tumor reactivity of this infiltrate (tumor infiltrating lymphocytes [TIL]) is poorly documented. This study examined the presence, phenotype and functional features of tumor-reactive lymphocytes in human CRC. Freshly dissociated TIL and T cell lines were isolated from CRC samples and from some paired normal colonic mucosa. Four tumor cell lines were obtained. Autologous tumor reactivity of CRC TIL and tumor-reactive cell features were analyzed. We demonstrate the presence among CRC TIL of variable fractions (up to 18%) of double positive CD4 1 CD8ab 1 (DP) ab T cells. Interestingly, a high proportion (16-20%) of this TIL subset displayed tumor reactivity, whilst this was the case for no or few single positive TIL. Low levels of DP TIL were found in most CRC samples and in normal colonic mucosa, but these cells were higher in metastatic CRC. Furthermore, we showed that DP TIL were polyclonal, restricted by HLA class-I, proliferated poorly and secreted higher amounts of IL-4 and IL-13 than single positive T cells, on cognate or CD3 stimulation. DP CRC TIL also expressed CD103, confirming their mucosal origin. Increased frequencies of tumor-reactive DP TIL in metastatic CRC suggest that these cells play a role in the metastatic process of this cancer. Based on their high secretion of IL-4 and IL-13 and on previously described roles of these cytokines in cancers, we postulate that DP TIL could favor CRC growth or metastasis and/or downmodulate immune responses to these tumors.Recent studies have highlighted the high prognostic value of the density of T cells infiltrating colorectal carcinomas (CRC), implying an important contribution of T-cell responses to the control of this cancer. 1 Nonetheless, contrary to other cancers such as melanomas, 2 evidence that CRC may induce tumor-specific T-cell responses in an autologous setting is still scarce. 3 This may be due to the difficulty in obtaining stable CRC cell lines required for the detection of T cells specific to individual tumor antigens such as frameshift mutations. 4 Alternatively, it might result from the presence of qualitatively unique T-cell responses in this cancer, which has not yet been appropriately addressed.We previously reported that CRC-reactive c9d2 T cells were present in several CRC ascites. 5 The aim of the present study was to analyze the presence of conventional and unconventional tumor-reactive ab T cells, such as CD4 þ CD8 þ double positive cells (DP), in a significant series of CRC.As reviewed by Parel et al., 6 DP T lymphocytes account for a small and heterogeneous subset of TCRab cells. At present, three subsets of these cells could be distinguished: (i) conventional CD8 þ T cells that on activation express low CD4 levels; (ii) conventional CD4 þ T cells that acquire longterm CD8aa expression in vivo, as a result of exposure to unknown factors associated with the intestinal environment, aging or HIV infection and (iii) T cells stably e...
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Late disruption of stapled oesophagojejunal anastomosis SirThe interesting case-report written by M. Burke and R. M. Kirk (Br. J. Surg. 1983; 7 0 246-7) raises the question of the true healing of end-toend stapled anastomosis. We have recently observed such a case of very late dehiscence of colorectal anastomosis undertaken with a circular stapler.A 16-year-old girl was operated upon for sigmoid volvulus, on 22 October 198 I . Sigmoidectomy with Hartmann's procedure was performed. Three months later, an end-to-end transanal colorectal anastomosis using a 31 mm EEA staple cartridge was fashioned under satisfactory conditions. The postoperative period was uneventful. Radiological studies were normal. On 12 January 1983, 1 year after restoration of continuity, the patient complained of a pelvic pain occurringafter an effort to defecate. It extended rapidly to the abdomen. At examination, typical signs of peritonitis were found and free air in the abdomen was demonstrated. Gastrografin enema showed a leak on the left side of the anastomosis (Fig.
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