A MONOCLONAL-ANTIBODY GENERATED BY ANTIGEN INOCULATION VIA TICK BITE IS REACTIVE TO THE BORRELIA-BURGDORFERI REV PROTEIN, A MEMBER OF THE 2.9-GENE FAMILY FOCUS

Murine monoclonal antibodies directed against proteins of Borrelia bur gdorferi B31 (low passage) were generated by the administration of ant igen via the bite of borrelia-infected ticks. This strategy was employ ed as a mechanism to create antibodies against antigens presented by t he natural route of tick transmission versus those presented by inocul ation with cultured borreliae. One of the resultant antibodies reacted with a 17-kDa antigen from cultured B. burgdorferi, as seen by immuno blot analysis. This antibody was used to screen a B. burgdorferi genom ic DNA lambda vector expression library, and an immunoreactive clone w as isolated. DNA sequence analysis of this clone, containing a 2.7-kb Insert, revealed several open reading frames. These open reading frame s were found to be homologs of genes discovered as a multicopy gene fa mily in the 297 strain of B. burgdorferi by Porcella et al. (S. F. Por cella, T. G. Popova, D. R. Akins, M. Li, J. D. Radolf, and M. V. Norga rd, J. Bacteriol. 178:3293-3307, 1996). By selectively subcloning gene s Found in this insert into an Escherichia coli plasmid expression vec tor, the observation was made that the rev gene product was the protei n reactive with the 17-kDa-specific monoclonal antibody. The rev gene product was found to be expressed in low-passage, but not in high-pass age, B. burgdorferi B31. Correspondingly, the rev gene was not present in strain B31 genomic DNA from cultures that had been passaged >50 ti mes. Serum samples from Lyme disease patients demonstrated an antibody response against the Rev protein. The generation of an anti-Rev respo nse in Lyme disease patients, and in mice by tick bite inoculation, pr ovides evidence that the Rev protein is expressed and immunogenic duri ng the course of natural transmission and infection.