Abstract: Objective To investigate the expression of ASK1 and PRKCD in the process of monocyte differentiation, and explore
their role in functional changes of hypersplenism spleen macrophages (MΦ) in portal hypertension (PH). Methods U937 cells
were stimulated to differentiate into monocyte/macrophage-like cells by cultivation in PMA and the mRNA expressions of
ASK1 and PRKCD were detected by q-PCR and the changes of protein expression were identified by western blot analysis. The
secretion of phagocytose related cytokines such as IL-10 and TNF-a were tested by ELISA, and the function of the
macrophage-like cells were studied by chicken red blood cell phagocytose test. Results The expressions of PRKCD and ASK1
mRNA were gradually decreased along with the cell differentiation, while the secretion of TNF-α was increased, IL-10
secretion reached a maximum at 24 h after PAM stimulation, and then gradually fell. The expression of ASK1 and p-ASK1
were rapidly increased compared with the non-stimulated U937 cells, while the expression of PRKCD and p-PRKCD were
sightly declined. The phagocytose test show that U937 cells induced with PMAwere able to swallow the chicken red blood cell.
Conclusion Up-regulated protein expression of ASK1 and p-ASK1 and down-regulated protein expression of PRKCD and
p-PRKCD in the process of PMA induced monocyte differentiation, are consist with the expression changes of splenic
macrophage phagocytosis in hypersplenism, which leads to increased activity of MΦ.