Neutralizing antibody responses to human herpesviruses 6 and 7 do not cross-react with each other, and maternal neutralizing antibodies contribute to sequential infection with these viruses in childhood.
Seroprevalence of human herpesvirus 6 (HHV-6) and HHV-7 infections is very high throughout the world, and almost all people are exposed first to HHV-6 and second to HHV-7 in their childhood. However, it is not clear whether the neutralizing (NT) antibody response between each virus is cross-reactive or not. To elucidate the NT antibody response between each virus, 55 serum samples from an adult group (subjects 22 to 88 years old) and 60 serum samples from a young group (subjects 2 to 18 years old) were examined by a dot blot method for detecting viral late antigen. Thirty-nine serum samples obtained from cord bloods and a few serum samples obtained from pediatric patients with exanthem subitum were also examined to assess the maternal transferred NT antibodies against each virus. The NT antibody titers against HHV-7 in the adult group remained high throughout all the individuals, and none were negative. Those against HHV-6 were high values in the young group but low values, including negative values (three samples), in the adult group. These results suggested that the NT antibody response to either HHV-6 or HHV-7 in each individual was specific to each virus and did not cross-react with each other. In the adult group, the NT antibody response to HHV-6 decreased, while that to HHV-7 remained high throughout all the individuals. Maternal transferred NT antibody titers against HHV-7 were higher and remained longer after birth than those of HHV-6, and these findings were in accord with the clinical observation that HHV-6 infection usually occurs earlier than HHV-7 infection.
Yoshida
Mariko
M
Department of Virology, Okayama University Graduate School of Medicine and Dentistry, Okayama, Japan. mariko@md.okayama-u.ac.jp
Torigoe
Sadayoshi
S
Ikeue
Kumiko
K
Yamada
Masao
M
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000914:Antibodies, Viral / Q000097:blood / Q000276:immunology*; D000918:Antibody Specificity; D002648:Child; D002675:Child, Preschool; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay; D005077:Exanthema Subitum / Q000276:immunology*; D015654:Herpesvirus 6, Human / Q000276:immunology*; D016199:Herpesvirus 7, Human / Q000276:immunology*; D006801:Humans; D007112:Immunity, Maternally-Acquired / Q000276:immunology; D007223:Infant; D007231:Infant, Newborn; D008875:Middle Aged; D009500:Neutralization Tests; D019349:Roseolovirus Infections / Q000276:immunology*
D000914:Antibodies, Viral