Anti Mycobacterium avium subsp. paratuberculosis heat shock protein 70 antibodies in the sera of Sardinian patients with multiple sclerosis.

 Heat shock protein (HSP) family members are highly conserved in both prokaryotic and eukaryotic organisms and are known to be immunodominant antigens in many bacteria. In particular, HSP70 has been linked to multiple sclerosis (MS), even if the available data are contradictory. Since different studies conducted on Sardinian subjects, have linked Mycobacterium avium subspecies paratuberculosis (MAP) presence to MS disease, and in view of the fact that human HSP70 is highly homologue to the majority of mycobacterial HSP70 proteins, we searched for anti-MAP HSP70 antibodies in the sera of 268 MS patients and 231 age and sex-matched healthy controls (HCs). All the subjects enrolled in the study were from Sardinia, which is an excellent setting for investigation since it has one of the highest prevalence of MS worldwide. HSP70 detection was carried out using ELISA methodology. A statistically significant difference was found between MS patients and HCs when analyzing the humoral response mounted against MAP HSP70 protein. Our study confirms that mycobacterial HSP70 might be involved in MS, and provides another piece of evidence sustaining the role played by MAP in MS in the context of Sardinian population.