Using Western blotting, we investigated IgG antibodies against Mycobacterium bovis heat shock protein 65 (MB-Hsp65) fragments produced by cleavage with cyanogen bromide (CNBr) in 10 healthy controls, 11 patients with juvenile idiopathic arthritis (JIA), and 10 children with various diseases before haematopoietic stem cell transplantation (HSCT). CNBr cleaved MB-Hsp65 to three larger fragments: P1-163, P191-285, and P290-534.
Sera of JIA patients and those before HSCT reacted with individual MB-Hsp65 fragments P1-163 and P290-534 significantly more frequently when compared with healthy controls. These results suggested that the key B-cell epitopes of MB-Hsp65 might be located on the aforementioned sequences.