Seroprevalence and Cross-reactivity of Human Polyomavirus 9

Jérôme T.J. Nicol, Antoine Touzé, Rémy Robinot, Francoise Arnold, Elisa Mazzoni, Mauro Tognon, and Pierre Coursaget

Author affiliations: Institut National de la Santé et de la Recherche Médicale, Tours, France (J.T.J. Nicol, A. Touzé, R. Robinot, F. Arnold, P. Coursaget); Université François Rabelais, Tours (J.T.J. Nicol, A. Touzé, R. Robinot, F. Arnold, P. Coursaget); and School of Medicine, University of Ferrara, Ferrara, Italy (E. Mazzoni, M. Tognon)

Abstract

Many humans have antibodies against simian lymphotropic polyomavirus (LPyV), but its DNA has not been found in humans. Identification of human polyomavirus 9 (HPyV9) led us to compare the seroprevalence and cross-reactivity of LPyV and HpyV9. Results could indicate that humans who have antibodies against LPyV are infected by HPyV9.

To date, 9 human polyomaviruses (HPyVs) have been identified: BK polyomavirus, JC polyomavirus, Karolinska Institute polyomavirus, Washington University polyomavirus, human polyomavirus 6 and 7, Trichodysplasia spinulosa-associated polyomavirus, Merkel cell polyomavirus (MCPyV), and human polyomavirus 9 (HPyV9), which was identified in 2010 in human blood and skin samples (1,2). Serologic studies have shown that most adults have been exposed to HPyVs, and cross-reactivity studies have shown antigenic similarities between simian virus 40 and BK polyomavirus and, to a lesser extent, between simian virus 40 and JC polyomavirus (3–5). Interpretation of phylogenetic analysis of viral protein 1 (VP1) sequences predicts that cross-reactivity might also occur between Trichodysplasia spinulosa-associated polyomavirus and Bornean orangutan PyV, between MCPyV and chimpanzee polyomaviruses, and between HPyV9 and simian lymphotropic polyomavirus (LPyV).
Serologic survey results have shown that 15.0%–30.0% of humans have antibodies against LPyV, suggesting that the human population has been exposed to an antigenically related PyV (4–6). However, because LPyV DNA sequences have not been reported among humans (7,8), LPyV has thus far been considered to be a virus with a narrow host range, limited to nonhuman primates. The 2010 identification of HPyV9 (1,2), a virus phylogenetically related to LPyV (84.0% of identity), led us to investigate the seroprevalence of this newly discovered polyomavirus and to evaluate the existence of cross-reactivity that might explain the LPyV seroprevalence in humans.