Diagnostic value of proteins of three Borrelia species (Borrelia burgdorferi sensu lato) and implications for development and use of recombinant antigens for serodiagnosis of Lyme borreliosis in Europe

More and more assays for the serodiagnosis of Lyme borreliosis (LB) are based on recombinant antigens. However, so far, there is no consensus as to which are the most specific and sensitive proteins and how they should be used in combination to obtain tests with the best discrimination abilities. The present study was preceded by a detailed analysis of Western blots (WB) using whole-cell lysates of Borrelia burgdorferi sensu stricto strain PKa2, B. afzelii PKo, and B. garinii PBi (U. Hauser, G. Lehnert, R. Lobentanzer, and B. Wilske, J. Clin. Microbiol. 35:1433-1444, 1997). For the present work, the data bank from that study, containing information about the reactivities of 330 sera (from patients at different stages of LB [n = 189]; control group, n = 141), was reused. The specificities and sensitivities of various combinations of proteins from different strains were calculated for different interpretation criteria. For immunoglobulin G (IgG) WE, the recommended combination of antigens available to date as recombinant proteins included p83/100 of PKa2, p83/100 of PKo, p39 of PKo, p39 of PBI, and OspC of PBi (interpretation criterion, at least one reactive band required for a positive WE; specificity, 96.5%; sensitivity, 56.1%). The further addition of p58 of PKo, p17 of PKo, or p14 of PKo was most favorable in terms of both a considerable gain of sensitivity and little loss of specificity. IgG Western blotting with a whole-cell lysate of strain PKo might be improved by the addition of OspC of PBi. For IgG WE, the best combination, out of all bands, was p83/100, p58, p39, p30, and p21 of all three strains and OspC of PBI, p17b of PBi, p56 of PKa2, p43 of PKo, p17 of PKo, and p14 of PKo (interpretation criterion, at least two reactive bands required for a positive WB; specificity, 97.2%; sensitivity, 61.4%). An interpretation criterion of at least two reactive bands is more reliable than one of only one reactive band. For IgM WB, the best combination was OspC of PKo, OspC of PBi, p39 of all three strains, p17 of PKo, and strong reactions with p41 of all three strains (interpretation criterion, at least one reactive band required; specificity, 97.9%; sensitivity, 47.0%).