Latent infection of human herpesvirus 7 in CD4(+) T lymphocytes.
To determine the cell populations in peripheral blood that are infected latently with human herpesvirus 7 (HHV-7), the real-time polymerase chain reaction (PCR) was used to determine the quantities of viral DNA in adherent and non-adherent cells from 71 healthy volunteers. Real-time PCR, which detected the U31 gene of HHV-7, was developed to measure viral load. The majority of non-adherent cells (14/16; 87.5%) contained HHV-7 DNA, while most of the adherent cells did not (1/16; 6.3%). HHV-7 viral load in non-adherent cells was significantly higher than that in adherent cells (P < 0.0001). Then, HHV-7 DNA load was compared between the CD4-positive and -negative cell fractions derived from the non-adherent cells of 26 healthy adults. As in the previous experiment, only 2 (7.7%) of the 26 adherent cell specimens contained small amounts of HHV-7 DNA (27.7 copies/1 x 10(6) cells and 208.7 copies/1 x 10(6) cells). In contrast, 88.5% of CD4(+) T cell samples (23/26 specimens) were positive for HHV-7 DNA, ranging from 0.4 to 3,542.8 copies/1 x 10(6) cells. Viral DNA was detected in only 3 (11.5%) of the 26 CD4(-) T cell specimens, with 8.4, 63.5, and 74.1 copies/1 x 10(6) cells. HHV-7-positive DNA loads were significantly higher in the CD4(+) T cells than those observed in the CD4(-) T cells (P = 0.0005). The relationship between HHV-7 viral loads in non-adherent cells and those in saliva was investigated. Comparison of HHV-7 DNA load between blood CD4(+) T cells and saliva revealed that the HHV-7 DNA load in saliva correlated with that present in CD4(+) T cells (r = 0.415; P = 0.0174).
Miyake
Fumi
F
Department of Pediatrics, Fujita Health University School of Medicine, Toyoake, Aichi, Japan.
Yoshikawa
Tetsushi
T
Sun
He
H
Kakimi
Akira
A
Ohashi
Masahiro
M
Akimoto
Shiho
S
Nishiyama
Yukihiro
Y
Asano
Yoshizo
Y
D000328:Adult; D015496:CD4-Positive T-Lymphocytes / Q000821:virology*; D002448:Cell Adhesion; D004279:DNA, Viral / Q000032:analysis; D005260:Female; D016199:Herpesvirus 7, Human / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology*; D006801:Humans; D008297:Male; D016133:Polymerase Chain Reaction; D019349:Roseolovirus Infections / Q000821:virology*; D012463:Saliva / Q000821:virology; D019562:Viral Load; D017735:Virus Latency
D004279:DNA, Viral