Role of high mobility group box protein 1 (HMGB1) in peripheral blood from patients with multiple sclerosis

Background: high mobility group box protein 1 (hmgb1) is a transcriptional regulator that is receiving increasing attention in autoimmune disorders including multiple sclerosis (ms). here,we investigated the role of hmgb1 in the peripheral blood compartment from ms patients. methods: hmgb1 mrna expression levels were determined by pcr in peripheral blood mononuclear cells (pbmc) of 29 healthy controls and 57 untreated ms patients (26 with relapsing-remitting ms - rrms,13 with secondary progressive ms - spms,and 18 with primary progressive ms - ppms). hmgb1 protein levels were measured by elisa in serum samples from 18 hc and 37 untreated ms patients (13 with rrms,14 with spms,and 10 with ppms). results: hmgb1 expression levels were increased in pbmc from the whole ms group compared with controls (p = 0.03). further stratification of the ms group revealed higher expression levels in pbmc from patients with relapse-onset ms,and differences were statistically significant for rrms patients compared with ppms patients and controls (p = 4 × 10-5 and p = 0.005,respectively) and also for spms patients compared with ppms patients (p = 0.001). hmgb1 serum levels were increased in the whole ms group compared with controls (p = 2 × 10-4). in ms clinical forms,the highest hmgb1 serum levels were observed in rrms patients,and differences were statistically significant compared to ppms patients (p = 5 × 10-5),spms patients (p = 0.001),and controls (p = 0.001). conclusions: these results point to a role of hmgb1 mrna and protein levels as disease activity biomarkers to discriminate the more inflammatory relapse-onset ms forms,particularly rrms,from the less inflammatory ppms form of the disease. © 2015 malhotra et al.; licensee biomed central.