Treponema pallidum upregulates prostaglandin E2 through BiP-PERK-COX-2 signaling pathway in vitro to inhibit the phagocytosis of macrophages

doi:10.3969/j.issn.1673-8640.2026.06.010

Abstract

Abstract:

Objective To analyze the effect of Treponema pallidum on the phagocytosis of macrophages and whether this effect is achieved through the regulation of prostaglandin E2 secretion pathway. Methods Human monocytic cell line THP-1 was differentiated into macrophages by phorbol myristate acetate（PMA） as the main cell experimental model. The phagocytosis of macrophages was determined by fluorescent microsphere phagocytosis assay. The secretion level of prostaglandin E2 in the cell supernatant was determined by enzyme-linked immunosorbent assay（ELISA）. The expression of endoplasmic reticulum stress marker proteins（BiP，PERK and COX-2） was determined by western blotting. BiP inhibitor，PERK inhibitor，COX-2 inhibitor and prostaglandin E2 antibody were used for intervention experiments to verify whether Treponema pallidum inhibited the phagocytosis of macrophages by upregulating prostaglandin E2 through the activation of BiP-PERK-COX-2 signaling pathway. Results Treponema pallidum inhibited the phagocytosis of fluorescent microspheres by macrophages in a concentration-dependent manner. Treponema pallidum induced the secretion of prostaglandin E2 by macrophages，and the use of prostaglandin E2 antibody could reverse the phagocytosis inhibition caused by Treponema pallidum. BiP inhibitor，PERK inhibitor and COX-2 inhibitor could all effectively inhibit the production of prostaglandin E2 and restore the phagocytosis of macrophages. Conclusions Treponema pallidum inhibits the phagocytosis of macrophages in vitro by upregulating prostaglandin E2 through the activation of BiP-PERK-COX-2 signaling pathway.

Key words: Treponema pallidum, Macrophage, Phagocytosis, Prostaglandin E2

CLC Number:

R377

YI Dongyu, CHEN Rong, LI Na, SHEN Zhenhua. Treponema pallidum upregulates prostaglandin E2 through BiP-PERK-COX-2 signaling pathway in vitro to inhibit the phagocytosis of macrophages[J]. Laboratory Medicine, 2026, 41(6): 583-589.

Figures/Tables 5

References 24

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