Increased circulating heat shock protein Hsp70 serum levels as a potential biomarker in bronchial asthma patients

The 70 kDa major stress-inducible member of the heat shock protein 70 family Hsp70 plays an important pathogenic role in inflammatory and autoimmune diseases, including bronchial asthma, and therefore the detection of the levels of the circulating chaperone in serum or plasma could be employed as a diagnostic and prognostic marker. The prospective open single-center study enrolled 78 adult bronchial asthma patients and age-matched healthy volunteers (n = 78). Serum HSP70 levels were measured using the ELISA Kit. Serum concentrations of HSP70 as detected by the R&D Systems Hsp70 ELISA in asthmatics patients were significantly higher as compared to control subjects constituting 31.2 ng/ml (p < 0.001) and were negatively correlated with FEV1 (forced expiratory volume in 1 s) and FEV1/FVC in all patients with bronchial asthma. When compared the chaperone levels in non-eosinophilic and eosinophilic (> 150 cells/µL) asthma patients, statistical significance was detected (p < 0.05). Analysis revealed a significant increase of cytokines (IL-4, IL-17, IL-25, IL-33) and TSLP in bronchial asthma patients. Strong correlation was observed between the Hsp70 level and smoking (p < 0.001), but not with age and gender: In conclusion, increased Hsp70 levels in serum of asthmatic patients may serve as a potential biomarker of the disease pending further validation.