We aimed to determine whether the viral DNA is detectable in tonsillar tissue of constitutionally healthy individuals, and what the corresponding antiviral seroreactivities are.
We tested 229 matched pairs of tonsillar tissue biopsies and serum samples from asymptomatic donors for TSPyV DNA by real-time quantitative PCR with primer pairs and Taq-Man probes targeting the VP1 and LT genes. The sera were studied by enzyme immunoassay (EIA) for TSPyV-VP1-IgG and the PCR-positive individuals also for -IgM and -IgG-avidity.
TSPyV DNA was detectable in 8 (3.5%) of 229 tonsillar tissues, and in none of the corresponding sera. TSPyV IgG seroprevalence among children was 39% and among adults 70%. Each of the 8 PCR-positive subjects had antiviral IgG of high avidity but not IgM.
TSPyV PCR positivity of tonsillar samples of individuals with long-term immunity provides the first evidence of TSPyV in tonsils and suggests lymphoid tissue as a latency site of this emerging human pathogen.