CCL2 enhances the viability of human chorionic trophoblast cell line HTR-8/SVneo Cells by inhibiting Interleukin-24 Expression

Abstract

Background: To investigate the regulatory effect of interleukin-24 (IL-24) on cell viability of human chorionic trophoblast cell line (HTR-8/SVneo cells). Methods: Immunohistochemical staining was used to detect the expression of IL-24 and its receptors IL-20R1, IL-20R2, and IL-22R1 in villus tissue at early normal pregnancy. The effect of thymic stromal lymphopoietin (TSLP) and chemokine CCL2 on the expression of IL-24 in human chorionic trophoblast cell line HTR-8/SVneo cells was analyzed by In-cell Western. In addition, the effect of recombinant human IL-24 (rhIL-24) and CCL2 on the viability of HTR-8/SVneo cells was analyzed by MTT assay. Results: IL-24 and its receptors showed a strong positive staining in trophoblasts at early normal pregnancy. Compared with control group, expression of IL-24 in HTR-8/SVneo cells was significantly inhibited after in vitro stimulation of recombinant human CCL2 protein (rhCCL2) (P < 0.001). The viability of HTR-8/SVneo cells was significantly decreased after treatment with rhIL-24 (P < 0.001). In contrast, anti-IL-24 neutralizing antibody significantly enhanced the viability of HTR-8/SVneo cells (P < 0.01). In addition, rhCCL2 (100 μg/L); enhanced the viability of HTR-8/SVneo cells (P < 0.01) in vitro, but this effect was inhibited by treatment with rhIL-24. Conclusions: CCL2 enhances the viability of human trophoblast cell line HTR-8/SVneo cells in vitro by inhibiting the secretion of IL-24, which may be beneficial to blastocyst implantation and placental development.

Keywords

• CCL2; Cell Viability; Chorionic Trophoblasts; HTR-8/SVneo Cells; Interleukin-24