Passive transfer of rabbit tick-immune serum to mice impairs the ability of <i>B. burgdorferi</i> infected nymphs to transmit spirochetes to mice.

<p>A. The ability of nymphs to feed on rabbits upon repeated infestation was decreased. Inset. Immunoblot of <i>B. burgdorferi</i> protein extract probed with anti-<i>Borrelia</i> antiserum (lane 1) or nymph-immune rabbit serum (lane 2). B. Inset. Quantitative RT-PCR assessment of <i>Borrelia</i> burden as scored by levels of <i>flaB</i> amplicons in the midguts (MG) and salivary glands (SG) of nymphs feeding on mice that received rabbit tick-immune serum (RTIS) or naive serum (NRS); and quantitative PCR assessment of <i>Borrelia</i> burden in the bladder and skin of mice that received rabbit tick-immune serum (RTIS) or naïve (NRS) serum.