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

Abstract

PurposeThis 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).MethodsPeripheral 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.ResultsThe 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).ConclusionThese 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.

Diagnostic value of peripheral blood immune profiling in colorectal cancer

“…Dynamic cross-talk between various types of immune cells and secretory molecules such as cytokines and chemokines, immunoglobulins, and complement constitutes the immune network [ 8 ]. Thus, immunity is not the effect of single cells or molecules but a net effect resulting from the several compartments of the whole immune system [ 6 9 ]. The peripheral blood stream as opposed to the central lymphoid organs allows systemic immunity to react rapidly to exogenous and endogenous dangers that are able to breach the host in a physiologically steady state [ 10 ].…”

Functional activity of natural killer cells in biological fluids in patients with colorectal and ovarian cancers

“…The number NK cells in peripheral blood is significantly decreased in patients with disseminated forms of ovarian cancer [ 12 ]. However, there are contradictory data on both reduction and increase in the number of peripheral blood NK cells in colorectal cancer patients [ 13 – 15 ]. In our study no significant differences in the number of peripheral blood NK cells between colorectal cancer patients and healthy donors was found.…”

Hemacytotoxicity and natural killer lytic index: New parameters to evaluate natural killer cell immunity for clinical use in cancer

“…NK cell cytotoxicity against K562 cells was tested following two different PBMC isolation methods as described in our previous work (12). K562 cells (KCLBNo.…”

“…PBMCs are typically employed in research laboratories, owing to the simple preparation procedures in comparison with NK cell-specific isolations (2,10). However, the use of pooled PBMCs prepared by a given number of cells as effector cells has a clear disadvantage: Variations in NK cell frequency in every pool of PBMCs hinders the accurate interpretation of a net-or per-cell cytotoxicity for NK cells, particularly since cytotoxicity, described as the percent (%) of dead target cells, tends to be strongly influenced by alterations in the NK cell population size within PBMC preparations (11)(12)(13).Considering these factors, PBMCs in cytotoxicity assays should be quantified per ml of blood to reflect the natural fluctuations in the NK cell population within the bloodstream. …”