title: Vpr in plasma of HIV type 1-positive patients is correlated with the HIV type 1 RNA titers.
abstract: Vpr, an accessory gene product of HIV-1, has been reported in the plasma of HIV-1-positive patients, and exogenous Vpr induces the reactivation of viral production from latently infected cells and the apoptosis of T cells in vitro. These observations imply that Vpr is important in AIDS development, but the clinical relevance of the findings cannot be evaluated fully because the actual plasma Vpr concentration in HIV-1-positive patients is unknown. Here we generated two monoclonal antibodies against different portions of Vpr and successfully identified Vpr as a 14-kDa protein in HIV-1-positive patients. Semiquantitative analysis using a recombinant Vpr revealed that the concentration of Vpr in patient plasma was approximately 0.7 nM (10 ng/ml). Cross-sectional analysis of 52 HIV-1-positive patients revealed that the presence of Vpr detected in 20 patients was positively correlated with HIV-1 RNA copy number (p > 0.03), but not with the number of CD4(+) T cells. This is the first report demonstrating the actual amount of Vpr in HIV-1-positive patients, and the possible linkage of Vpr and viral titers indicates that it is important to continue to carry out the sequential analysis of Vpr, especially in clinical courses of HIV-1-positive patients. The threshold of viral titers, where Vpr appears in the patients' plasma, if present, contributes to better understanding the role of Vpr in AIDS pathogenesis.
authors.affiliation: Research Institute, International Medical Center of Japan, Shinjuku-ku, Tokyo 162-8655, Japan.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Hoshino
authors.forename: Binlian
authors.initials: B
authors.lastname: Sun
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Konishi
authors.forename: Mari
authors.initials: M
authors.lastname: Shimura
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Segawa
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Hagiwara
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Koyanagi
authors.forename: Aikichi
authors.initials: A
authors.lastname: Iwamoto
authors.forename: Jun-Ichi
authors.initials: J
authors.lastname: Mimaya
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Terunuma
authors.forename: Shigeyuki
authors.initials: S
authors.lastname: Kano
authors.forename: Yukihito
authors.initials: Y
authors.lastname: Ishizaka
mesh_terms: D000328:Adult; D000911:Antibodies, Monoclonal; D001483:Base Sequence; D003430:Cross-Sectional Studies; D005260:Female; D016336:Gene Products, vpr / Q000032:analysis / Q000097:blood*; D015658:HIV Infections / Q000097:blood*; D015497:HIV-1 / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D012367:RNA, Viral / Q000032:analysis / Q000097:blood*; D019562:Viral Load; D054325:vpr Gene Products, Human Immunodeficiency Virus
chemical_list: D000911:Antibodies, Monoclonal; D016336:Gene Products, vpr; D012367:RNA, Viral; D054325:vpr Gene Products, Human Immunodeficiency Virus