In vitro influence of IL-24 on functions of CD8 + T cells from patients with non-small cell lung cancer / 中华微生物学和免疫学杂志

ABSTRACT

Objective:To investigate the in vitro influence of IL-24 on the functions of CD8 + T cells from patients with non-small cell lung cancer (NSCLC). Methods:Twenty-eight NSCLC patients and 17 healthy individuals were enrolled in this study. Peripheral blood mononuclear cells (PBMC) and bronchoalveolar lavage fluid (BALF) were collected to isolate CD8 + T cells. Real-time reverse transcription-PCR was used to detect the expression of IL-24 receptors (IL-20R1, IL-20R2 and IL-22R1) at mRNA level in CD8 + T cells. Changes in the expression of perforin and granzyme B were measured by flow cytometry after stimulating purified CD8 + T cells with different concentrations of recombinant human IL-24 (10 ng/ml and 100 ng/ml). In vitro direct and indirect contact co-culture systems were established for CD8 + T cells and NSCLC cell line (NCI-H1882 cells). CD8 + T cells induced target cell death and expression of IFN-γ and TNF-α in response to IL-24 stimulation were analyzed. Student′s t test or LSD- t test was used for intergroup comparison. Results:The expression of IL-22R1 at mRNA level was not detected in CD8 + T cells. No significant difference in IL-20R1 or IL-20R2 expression at mRNA level in CD8 + T cells was observed between healthy individuals and NSCLC patients, or between non-tumor sites and tumor sites ( P>0.05). Perforin and granzyme B expression was significantly reduced in CD8 + T cells from peripheral bloods and tumor sites of NSCLC patients as compared with those from healthy individuals and non-tumor sites (all P<0.05). Low concentration of IL-24 (10 ng/ml) did not affect perforin or granzyme B expression in CD8 + T cells ( P>0.05), but high concentration of IL-24 (100 ng/ml) significantly enhanced the expression of perforin and granzyme B in CD8 + T cells from NSCLC patients ( P<0.05). In the direct contact co-culture system, increased ratio of dead target cells and up-regulated IFN-γ and TNF-α expression were induced after stimulating CD8 + T cells from tumor sites in NSCLC patients with high concentration of IL-24 (100 ng/ml), but low concentration of IL-24 (10ng/ml) had no significant influence on CD8 + T cell-induced target cell death and cytokine production. In the indirect contact co-culture system, neither target cell death nor cytokine production induced by CD8 + T cells was affected by IL-24 stimulation. Conclusions:High concentration of IL-24 promoted the in vitro cytolytic function of CD8 + T cells from NSCLC patients, but might not influence the in vivo functions of CD8 + T cells.