title: Anti-V3 humanized antibody KD-247 effectively suppresses ex vivo generation of human immunodeficiency virus type 1 and affords sterile protection of monkeys against a heterologous simian/human immunodeficiency virus infection.
abstract: In an accompanying report (Y. Eda, M. Takizawa, T. Murakami, H. Maeda, K. Kimachi, H. Yonemura, S. Koyanagi, K. Shiosaki, H. Higuchi, K. Makizumi, T. Nakashima, K. Osatomi, S. Tokiyoshi, S. Matsushita, N. Yamamoto, and M. Honda, J. Virol. 80:5552-5562, 2006), we discuss our production of a high-affinity humanized monoclonal antibody, KD-247, by sequential immunization with V3 peptides derived from human immunodeficiency virus type 1 (HIV-1) clade B primary isolates. Epitope mapping revealed that KD-247 recognized the Pro-Gly-Arg V3 tip sequence conserved in HIV-1 clade B isolates. In this study, we further demonstrate that in vitro, KD-247 efficiently neutralizes CXCR4- and CCR5-tropic primary HIV-1 clade B and clade B' with matching neutralization sequence motifs but does not neutralize sequence-mismatched clade B and clade E isolates. Monkeys were provided sterile protection against heterologous simian/human immunodeficiency virus challenge by the passive transfer of a single high dose (45 mg per kg of body weight) of KD-247 and afforded partial protection by lower antibody doses (30 and 15 mg per kg). Protective neutralization endpoint titers in plasma at the time of virus challenge were 1:160 in animals passively transferred with a high dose of the antibody. The antiviral efficacy of the antibody was further confirmed by its suppression of the ex vivo generation of primary HIV-1 quasispecies in peripheral blood mononuclear cell cultures from HIV-infected individuals. Therefore, KD-247 promises to be a valuable tool not only as a passive immunization antibody for the prevention of HIV infection but also as an immunotherapy for the suppression of HIV in phenotype-matched HIV-infected individuals.
authors.affiliation: AIDS Research Center, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo 162-8640, Japan.
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Eda
authors.forename: Toshio
authors.initials: T
authors.lastname: Murakami
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Ami
authors.forename: Tadashi
authors.initials: T
authors.lastname: Nakasone
authors.forename: Mari
authors.initials: M
authors.lastname: Takizawa
authors.forename: Kenji
authors.initials: K
authors.lastname: Someya
authors.forename: Masahiko
authors.initials: M
authors.lastname: Kaizu
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Izumi
authors.forename: Naoto
authors.initials: N
authors.lastname: Yoshino
authors.forename: Shuzo
authors.initials: S
authors.lastname: Matsushita
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Higuchi
authors.forename: Hajime
authors.initials: H
authors.lastname: Matsui
authors.forename: Katsuaki
authors.initials: K
authors.lastname: Shinohara
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Takeuchi
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Koyanagi
authors.forename: Naoki
authors.initials: N
authors.lastname: Yamamoto
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Honda
mesh_terms: D020816:Amino Acid Motifs / Q000276:immunology; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D003429:Cross Reactions; D015483:HIV Antibodies / Q000276:immunology*; D015699:HIV Envelope Protein gp120 / Q000737:chemistry / Q000276:immunology*; D015658:HIV Infections / Q000821:virology*; D015497:HIV-1 / Q000145:classification / Q000276:immunology; D000882:Haplorhini; D006801:Humans; D007116:Immunization, Passive; D010446:Peptide Fragments / Q000276:immunology*; D016097:Simian Acquired Immunodeficiency Syndrome / Q000276:immunology; D015302:Simian Immunodeficiency Virus / Q000276:immunology; D013045:Species Specificity
chemical_list: D000911:Antibodies, Monoclonal; D015483:HIV Antibodies; D015699:HIV Envelope Protein gp120; D010446:Peptide Fragments