Fig. 5. CCL17 is increased in IL-13-responsive myeloid cells in BP patients, and CCL17 and PLA2G2A promote the secretion of IL-13 and pathogenic anti-BP180-NC16A autoantibody.

a Hierarchical plot showing inferred intercellular communication network of CCL17-CCR4 signaling. b The feature plot and the bar chart showing CCL17 mRNA expression within total skin cells between BP (n = 5) and HC (n = 8). c Protein level of CCL17 in serum from BP (n = 73) and HC (n = 32) by ELISA. d The feature plot and the bar chart showing CCR4 mRNA expression within total skin cells between BP (n = 5) and HC (n = 8). In the box plot b–d: Minima: Lower limit of the whisker. Maxima: Upper limit of the whisker. Center: Median line inside the box. The upper and lower box bounds represent the 25% and 75% percentile of data. e Flow plots of CD3⁺ T cells from PBMCs showing the expression of CCR4 treated by CCL17 recombinant protein (left panel), and the frequency of CCR4 (right panel) in BP (n = 30) and HC (n = 16) groups. f The positive correlation between the level of PLA2G2A and CCL17 in serum from in BP patients (n = 73). P-value was calculated using two-sided Pearson correlation test. r-value was Pearson correlation coefficient. g The level of CCL17 in PBMC from BP patients (n = 26) and HC (n = 7) treated with PLA2G2A recombinant protein. h Effect of CCL17 treatment on the IL-13 secretion from BP patients (n = 26) and HC (n = 13). i Effect of PLA2G2A treatment on the IL-13 secretion from BP patients (n = 20) and HC (n = 13). j, k ELISA analysis of anti-BP180-NC16A antibody titers in supernatants of CCL17 (j) or PLA2G2A (k) stimulated PBMCs from BP patients (n = 26) and HC (n = 22). P-values in b–d were calculated using two-sided Mann–Whitney U-test. P-values in e and g–k were calculated using paired two-sided Student’s t-test. *P < 0.05, **P < 0.01, ****P < 0.0001, only P-values < 0.05 are shown. Each sample is represented as one dot.