HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Ikeda, F. Articles by Hoshino, H. Search for Related Content PubMed PubMed Citation Articles by Ikeda, F. Articles by Hoshino, H.

Human Complement Component C1q Inhibits the Infectivity of Cell-Free HTLV-I¹

Fumihiro Ikeda^*,, Yuji Haraguchi, Atsushi Jinno, Yuichi Iino, Yasuo Morishita^*, Hiroshi Shiraki^§ and Hiroo Hoshino^2,

^* Second Department of Surgery and Departments of Hygiene and Virology and Emergency and Critical Care Medicine, Gunma University School of Medicine, Maebashi, Gunma, Japan; and ^§ Fukuoka Red Cross Blood Center, Chikushino, Fukuoka, Japan

Human T cell leukemia virus type I (HTLV-I) is a retrovirus that is not lysed by human serum or complement. It has not been determined, however, whether HTLV-I directly binds to complement components or whether it retains infectivity after incubation with human serum. We investigated the effects of human serum on the infectivity of cell-free HTLV-I produced by human and animal cells. Plating of vesicular stomatitis virus (HTLV-I) pseudotypes prepared in cat or human cells and formation of HTLV-I DNA after infection of cell-free HTLV-I produced by cat or human cells were markedly inhibited by treatment with fresh human serum, but not by heat-inactivated serum. HTLV-I infection was also inhibited by treatment with C2-, C3-, C6-, or C9-deficient serum, but not by C1q-deficient serum. Inhibitory activities of normal human serum against HTLV-I were neutralized by anti-C1q serum. Furthermore, purified C1q inhibited HTLV-I infection. The direct binding of C1q to HTLV-I was confirmed by comigration of C1q with HTLV-I virion upon sucrose density gradient ultracentrifugation of HTLV-I virion treated with C1q. Binding assay using synthetic envelope peptides indicated that C1q bound to an extramembrane region of the gp21 transmembrane protein. These findings indicate that the human complement component C1q inactivates HTLV-I infectivity.

This article has been cited by other articles:

				A. Mirsaliotis, K. Nurkiyanova, D. Lamb, J. M. Woof, and D. W. Brighty Conformation-Specific Antibodies Targeting the Trimer-of-Hairpins Motif of the Human T-Cell Leukemia Virus Type 1 Transmembrane Glycoprotein Recognize the Viral Envelope but Fail To Neutralize Viral Entry J. Virol., June 1, 2007; 81(11): 6019 - 6031. [Abstract] [Full Text] [PDF]

				U. Kishore, S. K. Gupta, M. V. Perdikoulis, M. S. Kojouharova, B. C. Urban, and K. B. M. Reid Modular Organization of the Carboxyl-Terminal, Globular Head Region of Human C1q A, B, and C Chains J. Immunol., July 15, 2003; 171(2): 812 - 820. [Abstract] [Full Text] [PDF]

				H. W. Favoreel, G. R. Van de Walle, H. J. Nauwynck, and M. B. Pensaert Virus complement evasion strategies J. Gen. Virol., January 1, 2003; 84(1): 1 - 15. [Abstract] [Full Text] [PDF]

				A. Jinno, Y. Haraguchi, H. Shiraki, and H. Hoshino Inhibition of Cell-Free Human T-Cell Leukemia Virus Type 1 Infection at a Postbinding Step by the Synthetic Peptide Derived from an Ectodomain of the gp21 Transmembrane Glycoprotein J. Virol., November 1, 1999; 73(11): 9683 - 9689. [Abstract] [Full Text] [PDF]