Anti-inflammatory protein of Schistosoma japonicum directs the differentiation of the WEHI-3B JCS cells and mouse bone marrow cells to macrophages.

Sj16 is an anti-inflammatory protein identified from Schistosoma japonicum. Our previous studies showed that recombinant Sj16 (rSj16) could suppress host's inflammatory responses and inhibit macrophage maturation. In the present study, the effects of rSj16 on the differentiation of the murine myeloid leukemia WEHI-3B JCS cell line and on mouse hematopoiesis were investigated. Our data demonstrated that rSj16 expressed and purified from Escherichia coli could suppress the proliferation of the WEHI-3B JCS cells in a time- and concentration-dependent manner, while not affect the viability of the cells. Further studies indicated that rSj16 induced macrophage differentiation of the WEHI-3B JCS cells, and arrested the cell cycle in the G1/G0 and G2/M phases. The macrophage differentiation of the rSj16-treated WEHI-3B JCS cells was confirmed by their expression of macrophage specific antigen F4/80 and phagocytic activity. Furthermore, our results revealed that rSj16 biased the colony formation of mouse bone marrow cells towards macrophage linage.