Fig. 1.

Increased frequency of circulating T follicular helper (cTfh) cells in multiple sclerosis (MS) patients than in healthy controls (HC). Fresh peripheral blood mononuclear cells (PBMCs) from HC and MS patients were surface‐stained with anti‐CD3, anti‐CD4, anti‐chemokine receptor type 5 (CXCR5) and anti‐programmed cell death 1 (PD‐1) antibodies. (a) Construction of fine singlets; representative example of flow cytometry gating of total live PBMCs by exclusion of debris, doublets and dead cells; (b) gating strategy: CD3⁺CD4⁺ T cells (left) were defined by gating them on PBMCs after constructing fine singlets, CXCR5⁺PD‐1⁺ cells (right) defined as cTfh cells which were selected by gating from CD3⁺CD4⁺ T cells (left); (c) percentages of CD4⁺ T cells in MS and HC were calculated and compared; (d) percentage of cTfh cells in MS patients was calculated and compared to that of HC, **P = 0·003. Each data point represents each individual.