Prevalence of IgG reactivity in Lyme borreliosis patients versus Borrelia garinii and Borrelia afzelii in a restricted area of Northern Italy

This survey evaluates the antibody band patterns of sera taken from clinically defined cases of Lyme borreliosis, towards three locally isolated strains of Borrelia burgdorferi, belonging to the three species: Borrelia sensu stricto, Borrelia garinii and Borrelia afzelii, by means of Western blot. The sera were taken from patients resident in a limited area of Friuli Venezia Giulia (FVG) region. The data indicated that, besides a different feature of the band reactivity which correlated to the different stages of Lyme borreliosis, there was a preferential reactivity to the species Borrelia afzelii and Borrelia garinii. An immunodominant band at 51 kDa, corresponding to a protein visible in the electrophoretic profile of strain BL3 (B. afzelii), behaved like a marker of an early infection, because it was present exclusively in the sera of patient with ECM. The overall findings would indicate that B. afzelii and B. garinii are the prevalent genospecies in the FVG area, even if strains belonging to B. sensu stricto have been also isolated in this area. Consequently strains representative of these two species must be used as antigens in Western blot.