Fig. 3

a BTLA expression, plotted as mean fluorescence intensity (MFI) with boxplots, for B cell subtypes: naïve, pre-plasmablasts (pre-PB), plasmablasts (PB), transitional B cells (TB), switched memory cells (SM), non-switched memory cells (NSM), and double negative memory cells (DNM). BTLA expression was not significantly different between naïve B cells, TB and pre-PB. #PB displayed significantly decreased BTLA expression compared to naïve cells (p = 0.002), TB (p < 0.0001), and pre-PB (p = 0.006). ¤SM, NSM and DNM displayed lower BTLA expression compared to all other cell types (p < 0,00002). SM displayed significantly lower expression compared to NSM (p = 0.03) and DNM (p = 0.003). BTLA expression on NSM and DNM did not differ significantly. All p-values corrected with Bonferroni-Holm method. Figure is based on results from analyses of samples from 44 blood donors. b BTLA expression with regard to age. Figure is based on results from analyses of samples from 22 blood donors < 41 years, and 22 blood donors > = 41 yrs. c BTLA expression with regard to sex. Figure is based on results from analyses of samples from 23 women and 21 men. The boxplots shows median, with the upper and lower quartile as box limits and whiskers as min and max if no outliers are present. Outliers are marked with a circle (1,5–3 IQR)