Lymphocyte reactivity against purified Lyme disease Borrelia cell components in individuals with neuroborreliosis

Lymphocyte proliferative responses to whole-cell antigen and three subcellular protein fractions of Lyme disease Borrelia were investigated. The lymphocytes were obtained from patients previously diagnosed as having early or late neuroborreliosis. Patients with late neuroborreliosis were tested 1–7 yr after antibiotic treatment of the disease. One of the subcellular protein fractions contained 12 proteins of defined molecular weights, the second fraction contained predominantly the outer surface proteins (Osp) A and OspB, and the third fraction contained, as the major component, the flagellum of Lyme disease Borrelia. This study demonstrated that the lymphocyte proliferative assay had a sensitivity of 88% in late neuroborreliosis patients and 75% in patients with previous early neuroborreliosis when whole cells were used as antigen. A similar sensitivity had previously been seen when the sera of these patients had been analysed for Borrelia burgdorferi-specific IgG antibodies. Of the three subcellular fractions, the flagellin fraction demonstrated the highest sensitivity, 64% in late neuroborreliosis patients and 62% in patients with previous early neuroborreliosis. Furthermore, the whole-cell antigen and the flagellin fraction showed matching specificity (73%) in this lymphocyte proliferative assay. The results of the present study show that the determination of lymphocyte proliferative responses to subcellular components of Borrelia is a useful complement to the determination of serological responses for the diagnosis of Lyme borreliosis. This study also showed that the lymphocyte proliferative assay had a sensitivity similar to that of serology, irrespective of whether patients had active borreliosis or if testing successfully treated patients.