CD40LG and eosinophilic esophagitis: An increase in plasma B cell proportions was a salient feature of active EoE (rising from a median of 0.021% of all cells in non-active EoE, including both healthy and remission, to 0.535% in active EoE), especially for IgG+ (from a median of 0 to 0.044% across patients, FDR < 0.05, Wald test), IgM+ (from a median of 0 to 0.0019% across patients, FDR < 0.05), and cycling (from median of 0 to 0.024% across patients, FDR < 0.05) plasma cells, which represent only a handful (0–22) of cells detected in non-active EoE (Fig. 2a, b, d, Supplementary Fig. 3e, Supplementary Fig. 5a, b).