Photo by mertguller from unsplash
Previous studies have shown that dexamethasone (Dex) reduces the levels of anti‐nuclear (ANA) and anti‐dsDNA antibodies in MRL/lpr mice (a mouse model of SLE). However, the effect of Dex on… Click to show full abstract
Previous studies have shown that dexamethasone (Dex) reduces the levels of anti‐nuclear (ANA) and anti‐dsDNA antibodies in MRL/lpr mice (a mouse model of SLE). However, the effect of Dex on T follicular helper (Tfh) cells is less documented. Here, using the MRL/lpr mouse model, we investigated the influence of Dex on Tfh cells and potential underlying mechanisms. The data showed that the proportion of Tfh cells, identified as CD4+CXCR5+ICOS+, CD4+CXCR5+PD‐1+ or CD4+BCL‐6+ cells, markedly decreased after treatment with the Dex, in both Balb/c mice and MRL/lpr mice. Dex significantly inhibited IL‐21 expression at both the mRNA and the protein levels. Dex also significantly reduced the proportion of germinal centre B cells and decreased serum IgG, IgG2a/b and IgA levels. Moreover, a positive correlation between the proportion of Tfh cells (CD4+CXCR5+ICOS+, CD4+CXCR5+PD‐1+ or CD4+BCL‐6+) and autoantibodies was observed. Dex significantly increased the Prdm1 and Stat5b mRNA expression and decreased the Bcl‐6 and c‐Maf mRNA expression of CD4+T cells. In brief, Dex inhibited the Tfh development, which relies on many other transcription factors in addition to Bcl‐6. Our data indicate that Dex can be used as a Tfh cell inhibitor in SLE.