Antibodies to CD9, a tetraspan transmembrane protein, inhibit canine distemper virus-induced cell-cell fusion but not virus-cell fusion.
Canine distemper virus (CDV) causes a life-threatening disease in several carnivores including domestic dogs. Recently, we identified a molecule, CD9, a member of the tetraspan transmembrane protein family, which facilitates, and antibodies to which inhibit, the infection of tissue culture cells with CDV (strain Onderstepoort). Here we describe that an anti-CD9 monoclonal antibody (MAb K41) did not interfere with binding of CDV to cells and uptake of virus. In addition, in single-step growth experiments, MAb K41 did not induce differences in the levels of viral mRNA and proteins. However, the virus release of syncytium-forming strains of CDV, the virus-induced cell-cell fusion in lytically infected cultures, and the cell-cell fusion of uninfected with persistently CDV-infected HeLa cells were strongly inhibited by MAb K41. These data indicate that anti-CD9 antibodies selectively block virus-induced cell-cell fusion, whereas virus-cell fusion is not affected.
Schmid
E
E
Institut für Virologie und Immunbiologie, D-97078 Würzburg, Germany.
Zurbriggen
A
A
Gassen
U
U
Rima
B
B
ter Meulen
V
V
Schneider-Schaulies
J
J
D000818:Animals; D000906:Antibodies / Q000276:immunology*; D015703:Antigens, CD / Q000276:immunology / Q000502:physiology*; D001921:Brain / Q000821:virology; D002459:Cell Fusion; D002462:Cell Membrane / Q000821:virology; D002478:Cells, Cultured; D002522:Chlorocebus aethiops; D004216:Distemper / Q000821:virology; D004217:Distemper Virus, Canine / Q000502:physiology*; D004285:Dogs; D015726:Giant Cells / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D008561:Membrane Fusion / Q000187:drug effects*; D008562:Membrane Glycoproteins; D012367:RNA, Viral / Q000378:metabolism; D060245:Tetraspanin 29; D014709:Vero Cells; D014764:Viral Proteins / Q000378:metabolism; D014774:Virulence
D000906:Antibodies; D015703:Antigens, CD; C554869:CD9 protein, human; D008562:Membrane Glycoproteins; D012367:RNA, Viral; D060245:Tetraspanin 29; D014764:Viral Proteins