title: Adaptation of feline immunodeficiency virus subtype B strain TM2 to a feline astrocyte cell line (G355-5 cells).
abstract: Based on receptor usage during infection, feline immunodeficiency virus (FIV) isolates can be divided into two groups; those that require feline CD134 (fCD134) as a primary receptor in addition to CXCR4 to enter the cells, and those that require CXCR4 only. Most primary isolates, including strain TM2, belong to the former group and cannot infect a feline astrocyte cell line (G355-5 cells) due to a lack of fCD134 expression. In a previous study, we found that G355-5 cells transduced with fCD134 (termed G355-5/fOX40 cells) were susceptible to strain TM2 and the inoculated cells became persistently infected. In this study, we examined the phenotype of the virus prepared from the persistently infected cells (termed strain TM2PI). Intriguingly, strain TM2PI replicated well in naïve G355-5 cells and the inoculated G355-5 cells (termed G355-5/TM2PI cells) became persistently infected. The infection of TM2PI in G355-5 cells was inhibited by CXCR4 antagonist AMD3100 and TM2PI infected other fCD134-negative, CXCR4-positive cell lines, FeTJ and 3201 cells. Four amino acid substitutions were found in the Env protein of the strain TM2PI when compared with that of the parental strain TM2. Among the substitutions, the Env amino acid position at 407 of TM2PI was substituted to lysine which has been known to be responsible for the FIV tropism for Crandell feline kidney cells. The strain TM2PI will be useful for studying the receptor switching mechanism and FIV pathogenesis in cats.
authors.affiliation: Laboratory of Signal Transduction, Department of Cell Biology, Institute for Virus Research, Kyoto University, 53 Shogoin-Kawaracho, Sakyo-ku, Kyoto 606-8507, Japan.
authors.forename: Mieko
authors.initials: M
authors.lastname: Ishikawa
authors.forename: Kenji
authors.initials: K
authors.lastname: Baba
authors.forename: Masayuki
authors.initials: M
authors.lastname: Shimojima
authors.forename: Masaya
authors.initials: M
authors.lastname: Okada
authors.forename: Takayuki
authors.initials: T
authors.lastname: Shojima
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Miura
authors.forename: Takayuki
authors.initials: T
authors.lastname: Miyazawa
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000821:virology*; D002415:Cats; D002460:Cell Line / Q000821:virology; D015686:Gene Products, env / Q000235:genetics* / Q000378:metabolism; D016089:Immunodeficiency Virus, Feline / Q000235:genetics / Q000254:growth & development*; D019718:Receptors, CXCR4 / Q000235:genetics / Q000378:metabolism; D053262:Receptors, OX40 / Q000235:genetics / Q000378:metabolism; D011991:Receptors, Virus / Q000235:genetics* / Q000378:metabolism; D014162:Transfection; D056189:Viral Tropism
chemical_list: D015686:Gene Products, env; D019718:Receptors, CXCR4; D053262:Receptors, OX40; D011991:Receptors, Virus