Extinct type of human parvovirus B19 persists in tonsillar B cells.

Extinct type of human parvovirus B19 persists in tonsillar B cells.

Nat Commun. 2017 Apr 04;8:14930

Authors: Pyöriä L, Toppinen M, Mäntylä E, Hedman L, Aaltonen LM, Vihinen-Ranta M, Ilmarinen T, Söderlund-Venermo M, Hedman K, Perdomo MF

Abstract
Parvovirus B19 (B19V) DNA persists lifelong in human tissues, but the cell type harbouring it remains unclear. We here explore B19V DNA distribution in B, T and monocyte cell lineages of recently excised tonsillar tissues from 77 individuals with an age range of 2-69 years. We show that B19V DNA is most frequent and abundant among B cells, and within them we find a B19V genotype that vanished from circulation >40 years ago. Since re-infection or re-activation are unlikely with this virus type, this finding supports the maintenance of pathogen-specific humoral immune responses as a consequence of B-cell long-term survival rather than continuous replenishment of the memory pool. Moreover, we demonstrate the mechanism of B19V internalization to be antibody dependent in two B-cell lines as well as in ex vivo isolated tonsillar B cells. This study provides direct evidence for a cell type accountable for B19V DNA tissue persistence.

PMID: 28374737 [PubMed - in process]

http://ift.tt/2oZPrxX