Expression of receptor for advanced glycation end products in sarcoid granulomas
AMERICAN JOURNAL OF RESPIRATORY AND CRITICAL CARE MEDICINE
Authors: Campo, Ilaria; Morbini, Patrizia; Zorzetto, Michele; Tinelli, Carmine; Brunetta, Enrico; Villa, Chiara; Bombieri, Cristina; Cuccia, Mariaclara; Agostini, Carlo; Bozzi, Valeria; Facoetti, Angelica; Ferrarotti, Ilaria; Mazzola, Paola; Scabini, Roberta; Semenzato, Gianpietro; Pignatti, Pier Franco; Pozzi, Ernesto; Luisetti, Maurizio
Abstract
Rationale:The receptor for advanced glycation end products(RAGE) engages a number of ligands implicated in inflammatory processes. The RAGE coding gene maps to the 6p21.32 region, close to the genes DRB1 and BTNL2, which are associated with sarcoidosis. Objectives: We investigated a possible implication of RAGE in sarcoid granulomas. Methods: RAGE and major ligands (N-epsilon-carboxy-methyl-lysine [CML], S100A12, and S100B) expression was investigated by immunostaining of 99 paraffin-embedded biopsies of sarcoid tissues, and expression patterns were determined. Among the three RAGE gene single-nucleoticle polymorphisms investigated, -374 T/A was selected, characterized in terms of transcriptional effect (immunocytochemistry and real-time polymerase chain reaction), and its frequency was determined in DNA extracted from biopsies. Measurements and Results: RAGE, CIVIL, S100A12, and S100B immunoreactivity was observed in all sarcoid granulomas, although at different intensities. The degree of RAGE expression significantly correlated with the degree of S100A12 expression. The -374 TT/AT genotypes, associated with higher RAGE transcriptional activity, were more frequent in the sarcoidosis biopsy group than in control subjects, and the association was confirmed in a second, independent series of 101 patients with sarcoidosis. Conclusions: We showed the association of RAGE and its ligands with sarcoiclosis and suggest that an intrinsic genetic factor could be in part involved in its expression. In Italian patients, the -374 T/A polymorphism seems to be significantly associated with this disease.
Exomic Sequencing of Immune-Related Genes Reveals Novel Candidate Variants Associated with Alopecia Universalis
PLOS ONE
Authors: Lee, Seungbok; Paik, Seung Hwan; Kim, Hyun-Jin; Ryu, Hyeong Ho; Cha, Soeun; Jo, Seong Jin; Eun, Hee Chul; Seo, Jeong-Sun; Kim, Jong-Il; Kwon, Oh Sang
Abstract
Alopecia areata (AA) is a common autoimmune disorder mostly presented as round patches of hair loss and subclassified into alopecia totalis/alopecia universalis (AT/AU) based on the area of alopecia. Although AA is relatively common, only 5% of AA patients progress to AT/AU, which affect the whole scalp and whole body respectively. To determine genetic determinants of this orphan disease, we undertook whole-exome sequencing of 6 samples from AU patients, and 26 variants in immune-related genes were selected as candidates. When an additional 14 AU samples were genotyped for these candidates, 6 of them remained at the level of significance in comparison with 155 Asian controls (p<1.92610(-3)). Linkage disequilibrium was observed between some of the most significant SNPs, including rs41559420 of HLA-DRB5 (p<0.001, OR 44.57) and rs28362679 of BTNL2 (p<0.001, OR 30.21). While BTNL2 was reported as a general susceptibility gene of AA previously, HLA-DRB5 has not been implicated in AA. In addition, we found several genetic variants in novel genes (HLA-DMB, TLR1, and PMS2) and discovered an additional locus on HLA-A, a known susceptibility gene of AA. This study provides further evidence for the association of previously reported genes with AA and novel findings such as HLA-DRB5, which might represent a hidden culprit gene for AU.