Erucic acid improves the pregnancy complicated with systemic lupus erythematosus by inhibiting the effector function of CD8+ T cell

Pathogenic CD8+ T cells are closely related to the development of systemic lupus erythematosus. Erucic acid (EA) has been proved to have anti-inflammatory activity. However, whether EA can regulate pathogenic CD8+ T cells function in pregnancy complicated with systemic lupus erythematosus (pSLE) has not been investigated. In our study, we detected enhanced CD8+ T cell effector function and decreased EA levels in patients with pSLE compared to healthy pregnancy control. Plasma EA levels were negatively correlated with the severity complications of pSLE. In blood from patients with pSLE, EA inhibited the effector function of CD8+ T cells and the maintenance of stem cell-like memory CD8+ T cells. Mechanically, EA inhibited STAT3 phosphorylation and promoted ferroptosis, which contributed directly to the attenuated effector function of CD8+ T cells in pSLE. Moreover, EA supplementation in pregnant MRL/lpr mice inhibited the effector function of uterine CD8+ T cells and alleviated placental pathological damage. Our findings reveal the modulatory effects of EA on pathogenic CD8+ T cells from an immune response perspective, thus providing new insights into therapeutic strategy for patients with pSLE.