@article{mbs:/content/journal/jgv/10.1099/0022-1317-78-1-83, author = "Okamoto, Kousuke and Tsurudome, Masato and Ohgimoto, Shinji and Kawano, Mitsuo and Nishio, Machiko and Komada, Hiroshi and Ito, Morihiro and Sakakura, Yasuo and Ito, Yasuhiko", title = "An anti-fusion regulatory protein-1 monoclonal antibody suppresses human parainfluenza virus type 2-induced cell fusion", journal= "Journal of General Virology", year = "1997", volume = "78", number = "1", pages = "83-89", doi = "https://doi.org/10.1099/0022-1317-78-1-83", url = "https://www.microbiologyresearch.org/content/journal/jgv/10.1099/0022-1317-78-1-83", publisher = "Microbiology Society", issn = "1465-2099", type = "Journal Article", abstract = "Fusion regulatory protein-1 (FRP-1) regulates virus-mediated cell fusion and induces polykaryocyte formation of monocytes without any fusogen. We have recently reported that FRP-1 and the 4F2/CD98 heavy chain are identical molecules. Cell fusion in Newcastle disease virus (NDV)-infected HeLa cells was enhanced when cells were incubated with anti-FRP-1 MAb. Anti-FRP-1 MAbs also induced human immunodeficiency virus gp160-mediated cell fusion. However, HBJ127, an anti-FRP- 1/4F2/CD98 MAb that enhanced cell fusion in NDV- infected cells, delayed human parainfluenza virus type 2 (HPIV-2)-induced cell fusion in HeLa cells, although these viruses belong to the same genus Rubulavirus. No anti-FRP-1 MAbs enhanced cellfusion in HPIV-2-infected HeLa cells. Anti-FRP-1 MAbs including HBJ127 showed no effect on virus growth and expression levels of virus-specific polypeptides in HPIV-2-infected HeLa cells, indicating thatthe delay in cell fusion by an anti-FRP-1 MAb is not due to suppression of virus replication. When HeLa cells were transfected with an expression vector harbouring HPIV-2 HN and F genes, cell fusion was also suppressed by HBJ127, but the effect was weak in comparison with virus-infected cells. These data indicate anti-FRP-1 antibodies not only induce/enhance, but also inhibit/delay virus- induced cell fusion and therefore FRP-1 molecules are multifunctional.", }