Diagnostic value of peripheral blood immune profiling in colorectal cancer

PURPOSE: Little is known about the clinical value of peripheral blood immune profiling. Here, we aimed to identify colorectal cancer (CRC)-related peripheral blood immune cells and develop liquid biopsy-based immune profiling models for CRC diagnosis. METHODS: Peripheral blood from 131 preoperative patients with CRC and 174 healthy controls was analyzed by flow cytometry and automated hematology. CRC-related immune factors were identified by comparing the mean values of immune cell percentages and counts. Subsequently, CRC diagnostic algorithms were constructed using binary logistic regression. RESULTS: Significant differences were observed in percentages and counts of white blood cells, lymphocytes, neutrophils, regulatory T cells, and myeloid-derived suppressor cells (MDSCs) of patients and controls. The neutrophil/lymphocyte and Th1/Th2 ratios were also significantly different. Likewise, the percentages and counts of peripheral blood programed death 1, cytotoxic T lymphocyte antigen 4, B-and T-lymphocyte attenuator, and lymphocyte activation gene-3 were higher in patients with CRC. The binary logistic regression model included 12 variables, age, CD3+%, NK%, CD4+CD279+%, CD4+CD25+%, CD4+CD152+%, CD3+CD366+%, CD3+CD272+%, CD3+CD223+%, CD158b−CD314+CD3−CD56+%, Th2%, and MDSCs cells/µL, for the prediction of cancer. Results of retrospective and prospective evaluation of the area under the curve, sensitivity, and specificity were 0.980 and 0.940, 91.53% and 85.80%, and 93.50% and 86.20%, respectively. CONCLUSION: Peripheral blood immune profiling may be valuable in evaluating the immunity of CRC patients. Our liquid biopsy-based immune diagnostic method and its algorithms may serve as a novel tool for CRC diagnosis. Future largescale studies are needed for better characterization of its diagnostic value and potential for clinical application.

Reference Values for Peripheral Blood Lymphocyte Subsets in a Healthy Korean Population

Flow cytometric immunophenotyping of peripheral blood lymphocyte subsets is a powerful tool for evaluating cellular immunity and monitoring immune-mediated diseases. The numbers and proportions of blood lymphocyte subsets are influenced by factors such as gender, age, ethnicity, and lifestyle. This study aimed to establish reference ranges for peripheral blood lymphocyte subsets in a healthy Korean population. Blood samples from 294 healthy adults were collected. Lymphocyte subsets were analyzed using a single-platform method with a flow cytometer; white blood cells and lymphocytes were analyzed using an automated hematology analyzer. The mean value of the white blood cell count was 5,665 cells/microl, and the mean values of the subtype counts (percentages) were as follows: lymphocytes, 1,928 cells/microl (35.08%); CD3+ cells, 1,305 cells/microl (67.53%); CD3+CD4+ cells, 787 cells/microl (40.55%); CD3+CD8+ cells, 479 cells/microl (25.23%); CD3-CD19+ cells, 203 cells/microl (10.43%); and CD3-CD56+ cells, 300 cells/microl (15.63%). Additionally, the CD4+/CD8+ ratio was 1.81. In this study, gender and age significantly influenced blood lymphocyte subsets. Our results demonstrate that, as with other populations, a healthy Korean population has its own, region-specific, lymphocyte subset reference ranges.

Evaluation of cytolytic activity and phenotypic changes of circulating blood immune cells in patients with colorectal cancer by a simple preparation of peripheral blood mononuclear cells / 대한외과학회지

PURPOSE: This study aimed to assess the cytolytic activity and the phenotype of circulating blood immune cells in cancer patients by using a simple preparation of peripheral blood mononuclear cells (PBMCs). METHODS: Peripheral blood was obtained from 94 diagnosed colorectal cancer (CRC) patients and 112 healthy donors. PBMCs were cocultured with K562 cells for 2 hours and lactate dehydrogenase released from the dead K562 cells was measured by using a spectrophotometer. Meanwhile, PBMCs were stained with fluorescence conjugated monoclonal antibodies (mAbs) and analyzed by flow cytometry. RESULTS: The cytolytic activity of PBMCs were significantly different between CRC patient and healthy groups (8.82% +/- 3.84% vs. 17.51% +/- 8.57%; P < 0.001). However, no significant difference in the cytolytic activity was observed after surgery in the CRC patient group (before surgery, 8.82% +/- 3.84% vs. after surgery, 9.95% +/- 4.94%; P = 0.326). In addition, the percentage of peripheral blood natural killer cells was significantly higher in the preoperative patient group than in the healthy group (19.97% +/- 11.51% vs. 15.60% +/- 5.77%, P = 0.041). In contrast, the percentage of peripheral blood lymphocytes was lower in the preoperative patient group than in the healthy group (28.41% +/- 8.31% vs. 36.4% +/- 8.6%, P < 0.001). CONCLUSION: These results demonstrate that circulating blood immune cells of CRC patients are functionally impaired and undergo an immunophenotypic perturbation, and show that a simple preparation of PBMCs can be useful to evaluate cellular immunity in cancer.