Anti-p35

The p35 kDa protein of the spirochete Borrelia burgdorferi is being investigated for use as an early diagnostic marker of Lyme Disease. Borrelia may change its antigenic composition in its need for adaptation to stresses imposed by changes in conditions from cycling between its arthropod and mammalian hosts. This group of B. burgdorferi proteins may be induced in the tick midgut during the feeding event. The p35 protein elicits a protective immunity from wild type B. burgdorferi. It has been shown that p35 expression in B. burgdorferi is upregulated in the stationary growth phase, and that a temperature of 34°C but not 24°C influenced the expression. The expression of a majority of the proteins expressed in early Lyme disease is affected pH, being abundantly expressed at pH 7.0 (resembling the tick midgut pH of 6.8 during feeding) but only sparsely at pH 8.0 (a condition closer to that of the unfed tick midgut pH of 7.4). The encoding genes may be coregulated. The 35-kDa antigen has been shown to be a statistically significant marker in IgG immunoblots in a study of patients with early Lyme disease who presented with erythema migrans. Recombinant p35 protein may be useful as a diagnostic reagent, especially in combination with other antigens that have been deemed relevant in serodiagnosis of early Lyme disease.