Establishment of titration system for human herpesvirus 6 and evaluation of neutralizing antibody response to the virus.
The susceptibilities of seven T-cell lines to human herpesvirus 6 (HHV-6) infection were examined. MT-4 cells were the most susceptible of these lines to infection with this virus. Therefore, chemically adhered MT-4 cell monolayers were used for infectious HHV-6 assay by indirect immunofluorescent-antibody (IFA) staining. When cell monolayers were fixed 30 to 45 h postinfection, the foci stained with IFA were easy to count and a linear relationship was observed between the number of foci and the virus concentration. MT-4 cell monolayers were also used for a focus reduction neutralizing-antibody test. In this test, sera from patients in the convalescent stage of exanthem subitum all showed significant neutralizing activity (1:80 to 1:320), whereas sera from patients in the acute stage of disease showed no detectable neutralizing activity. The titers of neutralizing antibody correlated well with the levels of anti-HHV-6 antibodies detected by IFA.
Asada
H
H
Department of Virology, Osaka University, Japan.
Yalcin
S
S
Balachandra
K
K
Higashi
K
K
Yamanishi
K
K
D000914:Antibodies, Viral / Q000032:analysis / Q000096:biosynthesis; D002460:Cell Line; D005077:Exanthema Subitum / Q000276:immunology / Q000382:microbiology; D006564:Herpesviridae / Q000145:classification / Q000276:immunology / Q000302:isolation & purification*; D006566:Herpesviridae Infections / Q000276:immunology; D006801:Humans; D007223:Infant; D009500:Neutralization Tests; D013601:T-Lymphocytes / Q000276:immunology
D000914:Antibodies, Viral