Regulatory T cells and monocytes crosstalk in patients with gastric cancer.

INTRODUCTION: Primary function of regulatory T(Treg) cells is to control and regulate the immune responses. In many patients with tumor tissues, increased Treg cell numbers have been reported. In this study, we aimed to measure the cellular content of blood samples in patients with gastric cancer (GC) and define their role in tumor progression. METHODS: We prospectively evaluated 34 gastric cancer cases and 20 healthy control samples. The blood was collected from both the gastric coronary and peripheral veins of the patients and only from the peripheral vein of the control group. Cellular content and lymphocyte subset including, regulatory T cells, were determined by flow cytometric analysis. RESULTS: The GC patients revealed similar percentages of T cells, B cells, neutrophils, and eosinophils in the venous samples from periphery vein and gastric coronary. The percentage of monocytes from the tumor-draining gastric coronary vein was significantly lower than monocytes from the peripheral vein in gastric cancer patients (p=0.03). T-regulatory cells had a higher percentage in samples obtained from gastric cancer patients compared with the control group. CONCLUSION: Our findings confirmed that patients with gastric cancer have a significantly higher percentage of regulatory T cells than the control group, suggesting that they may contribute to the tumor progress. Regulatory T cells and monocytes interact in patients with GC, which can be used as a parameter in the clinical follow-up of patients with GC. KEY WORDS: Gastric cancer, Treg cell, Flow cytometry, FoxP3.

Effects of erythropoietin on bacterial translocation in a rat model of experimental colitis.

OBJECTIVES: In this experimental study, it was aimed to assess the effects of erythropoietin (EPO) on bacterial translocation in a rat model of colitis. MATERIAL AND METHODS: The rats were randomly assigned into control, colitis and EPO-treated groups (n= 8 in each group). Saline solution (NS) was administered to control rats via rectal route. A trinitrobenzene sulfonic acid and ethanol mixture (TNBS-E) was used to induce colitis in the experiment groups. No treatment was administered to colitis group after induction. Starting at one day after induction of colitis with TNBS-E, EPO (1000 IU/kg) was administered subcutaneously for three days to the rats in the EPO-treated group. Colonic inflammation was assessed by gross and microscopic examination on day five. Blood samples were obtained to evaluate bacterial translocation while hepatic, mesenteric tissue samples and mesenteric lymph node (MLN) samples were collected for tissue culture. Tissue myeloperoxidase (MPO) levels, and tumor necrosis factor alpha (TNF- α) and endotoxin levels in the sera were studied. RESULTS: Significant gross and microscopic differences were found in the comparison between colitis and EPO-treated groups (p <0.05). MPO level was significantly lower when compared to the colitis group (p <0.05). Serum TNF-α and plasma endotoxin levels were significantly lower in the EPO-treated group than the colitis group (p <0.05). Bacterial translocation was lower in the liver, spleen, MLNs and systemic blood in the EPO-treated group when compared to the colitis group (p <0.05). CONCLUSION: In TNBS-E-induced rat model of colitis, EPO significantly decreased inflammation and bacterial translocation based on histopathological, biochemical and microbiological parameters.