Inflammasome activation and vitiligo/nonsegmental vitiligo progression

Summary Background Polymorphisms of NLR (nucleotide‐binding domain and leucine rich repeat containing) family, pyrin domain containing protein 1 ( NLRP 1) have been found in patients with vitiligo/nonsegmental vitiligo ( NSV ), and increased NLRP 1 expression has been detected in the leading edge of lesional skin biopsies. Objectives To evaluate the presence and intensity of NLRP 1 immunostaining in lesional and perilesional skin of patients with vitiligo/ NSV and to search for possible correlations between NLRP 1 and interleukin ( IL )‐1β expression, lymphocytic infiltrates and disease activity. Methods Of 14 consecutive vitiligo/ NSV patients, eight had active disease [ V itiligo E uropean T ask F orce ( VETF ) spreading score +1 to +5], one patient had stable disease and five patients had regressive disease ( VETF spreading score −1 to −3). We performed immunostaining for NLRP 1, B and T lymphocytes, IL ‐1β and kallikrein 7 on lesional and perilesional vitiligo skin. Results NLRP 1 and IL ‐1β immunostaining in perilesional vitiligo/ NSV skin was significantly associated with progressive disease ( P  =   0·009 and 0·04, respectively) and performed better than the simple detection of lymphocytic infiltrates. Conclusions Our findings suggest that markers of the NLRP 1 inflammasome could be a useful test for assessing disease activity in addition to the detection of inflammatory infiltrates in the progressing margins of vitiligo/ NSV lesions.