Altered CD27-related T cell subsets reflect immune imbalance in systemic lupus erythematosus

This study aims to analyze CD27 expression in various subsets of CD4+ T cells in peripheral blood, explore the functional characteristics of the CD27+ subsets in regulatory T cells (Tregs) and CD4+ T cells, and assess their immunological alterations in newly diagnosed systemic lupus erythematosus (SLE) patients.

Peripheral blood was collected from 34 newly diagnosed, untreated SLE patients and 22 healthy controls. Flow cytometry was used to analyze CD27 expression on T cell subsets, comparing the functional markers between CD27+ and CD27- subsets. CD27 expression on Tregs and total CD4+ T cells in SLE patients and healthy controls were compared. ROC curves were constructed, and areas under the curve (AUCs) was calculated to evaluate the diagnostic value of CD27-related T cell subsets for SLE.

The proportion of Tregs in the peripheral blood of SLE patients was increased, and CD27 expression was higher in Tregs than in CD4+ T cells in healthy individuals. CD27+ CD4+ T cells exhibited higher CD45RA and lower CD226 expression. CD27+ Tregs showed higher Helios and TIGIT expression and lower CD226 expression. CD27+ cell proportions in both CD4+ T cells and Tregs were significantly reduced in SLE patients. The AUC for CD27-related T cell subsets in diagnosing newly diagnosed SLE ranged from 0.6238 to 0.86.

CD27⁺ CD4⁺ T cells show reduced activation features, while CD27⁺ Tregs exhibit enhanced regulatory potential. Their decreased proportions in SLE patients suggest early immune dysregulation.