T helper cell-mediated in vitro responses of recently and remotely infected subjects to a candidate recombinant vaccine for human parvovirus b19.
T cell proliferation to human parvovirus B19 antigen was measured in 6 patients with recent B19 infection (1 with pneumonia and pleuritis), 1 patient with symptoms persisting >180 days after onset, 18 nonsymptomatic subjects with remote B19 immunity, and 12 B19-seronegative control subjects. Recombinantly expressed virus-like particles (VP1/2 capsids), a candidate B19 vaccine, were used as antigen. Virus-specific T helper cell proliferation was detectable in all the recently infected patients and in most (17/18) of the remotely infected subjects but not in the seronegative control subjects. The B19-specific T cell responses, in general, were most vigorous among the recently infected patients. However, such strong B19-specific proliferation was not confined within the acute phase, as 28% (5/18) of the remotely infected healthy individuals had B19-specific reactivity persisting at acute-phase levels, apparently for years or decades. These data indicate that B cells recognizing the VP1/2 capsids receive class II-restricted help from CD4(+) T lymphocytes.
Franssila
R
R
Department of Virology, Haartman Institute and Helsinki University Central Hospital Diagnostic, University of Helsinki, Helsinki, Finland FIN-00014. rauli.franssila@helsinki.fi
Hokynar
K
K
Hedman
K
K
D000210:Acute-Phase Reaction; D000328:Adult; D000956:Antigens, Viral / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology; D002213:Capsid / Q000235:genetics / Q000276:immunology; D002478:Cells, Cultured; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010322:Parvoviridae Infections / Q000517:prevention & control*; D016732:Parvovirus B19, Human / Q000235:genetics / Q000276:immunology*; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*; D014614:Vaccines, Synthetic / Q000276:immunology*; D014765:Viral Vaccines / Q000276:immunology*
D000956:Antigens, Viral; D014614:Vaccines, Synthetic; D014765:Viral Vaccines