[Expression and significance of myeloid-derived suppressor cells-associated chemokine MIP-1γ and its receptor CCR1 in the spleen of hepatoma H22-bearing mice].

Objective To study the expression and significance of myeloid-derived suppressor cell (MDSC)-associated chemokines in the spleen of hepatoma H22-bearing mice. Methods The percentage of splenic MDSCs was examined by flow cytometry. Splenic MDSCs were sorted using flow cytometry and co-cultured with activated splenocytes, and then the level of IFN-γ in the supernatant of co-cultured cells was assayed by ELISA. The murine orthotopic hepatoma model was established. The differential cytokine expression in the spleens of normal and tumor-bearing mice was assayed by protein chip, and splenic MDSC-associated chemokines were verified using ELISA. The chemokine receptors on splenic MDSCs were also detected by flow cytometry. Results The percentage of splenic MDSCs was markedly raised in the tumor-bearing mice, and splenic MDSCs exhibited immune-inhibitory function. Ten up-regulated cytokines and nine down-regulated ones were found out using protein chip. Among the up-regulated cytokines, 5 cytokines were chemokines, namely B lymphocyte chemoattractant (BLC), chemokine (C-X-C motif) ligand 16 (CXCL16), macrophage/monocyte chemotactic protein-5 (MCP-5), macrophage inflammatory protein 1γ (MIP-1γ) and MIP-2. The level of splenic MDSC-associated chemokine MIP-1γ significantly increased in the spleen of tumor-bearing mice, and its receptor CCR1 was also expressed on the cell surface of splenic MDSCs. Conclusion Splenic MDSC-associated chemokine MIP-1γ and its receptor CCR1 were obtained by protein chip, and they might be associated with the accumulation of splenic MDSCs in hepatoma H22-bearing mice.