CD4+ T-lymphocytes are activated by surgical stress following colorectal resection in cancer patients.

The aim of the present study was to measure adenosine triphosphate (ATP) levels in CD4+ T cells as a marker of T-cell activity following surgery for colorectal cancer using the ImmuKnow assay kit. A total of 16 consecutive patients who underwent surgical resection for colorectal cancer between August and December, 2012 were enrolled in this study, of whom 7 underwent laparoscopic resection and 9 underwent open abdominal surgery. The intracellular ATP levels in CD4+ T-lymphocytes were measured using the ImmuKnow assay kit preoperatively and on the 1st, 4th and 8th postoperative days, as were the white blood cell (WBC) count, lymphocyte count and C-reactive protein (CRP) levels. The ATP level of the CD4+ T-cells was significantly elevated on the 1st day following surgery compared to the preoperative level (P<0.01) and gradually returned to preoperative levels; the lymphocyte count was significantly decreased on the 1st postoperative day (P<0.001). In addition, the ImmuKnow assay demonstrated that only the ATP level, but not the WBC count, lymphocyte count or CRP level, exhibited a significant difference on the 1st (P=0.080) and 8th (P=0.042) postoperative days between the laparoscopic and open abdominal surgery groups. In conclusion, the ATP level of CD4+ T-lymphocytes was increased in response to surgical stress, in tandem with a decrease in the lymphocyte count. Therefore, the ImmuKnow assay kit may be clinically applicable for monitoring the immune response following surgery, as it exhibits a higher sensitivity compared to other assays.