T-cell reactivity against HSP60 relates to early but not advanced atherosclerosis

Background Anti-heat-shock protein 60 (HSP60) antibody-levels have been linked to carotid atherosclerosis and cardiovascular risk in a variety of studies. The potential role of cellular immune reactions against HSP60 has so far attracted little attention in epidemiological research. Methods and results In vitro T-cell reactivity to various HSP60s and tuberculin was assessed in blood samples from a elderly subpopulation of the Bruneck study (100 men, 50–69 years) and the young participants of the ARMY study (141 men, 17–18 years), and analyzed for a potential association with common carotoid artery intima-media thickness (IMT). In vivo skin reaction against tuberculin was recorded in subjects of the Bruneck study and correlated with the in vitro proliferative response to tuberculin (P = 0.004). T-cells isolated from peripheral blood of all individuals proliferated upon stimulation with HSP60s. In multivariate linear regression analysis adjusted for standard risk factors, T-cell stimulation was significantly related to IMT in the ARMY (P = 0.005 for human HSP60 and P = 0.064 for mycobacterial HSP60) but not in the Bruneck study. Conclusions T-cell reactivity against HSP60s correlated with IMT in male youngsters but not in men aged 50 and over, indicating a more prominent role of specific cellular immunity to HSP60s in the young and very early stages of atherosclerosis.