Development of IL-2-independent feline lymphoid cell lines chronically infected with feline immunodeficiency virus: importance for diagnostic reagents and vaccines

Intervirology. 1991;32(6):361-75. doi: 10.1159/000150220.


Two interleukin 2 (IL-2)-independent feline immunodeficiency virus (FIV) producer cell lines (FL-4 and FL-6) were produced by selecting cells from an IL-2-dependent culture of mixed peripheral blood lymphocytes infected with FIV. The new cell lines have been stable for over 1 year and spontaneously produce FIV with an average reverse transcriptase titer of 300,000 cpm/ml and an average sucrose gradient purified viral protein concentration of 1 mg/l. FIV produced from these cultures is highly infectious in vitro and in vivo. The FL-6 cell line was phenotyped as expressing the feline CD8 and Pan-T antigens, while the FL-4 cell line expressed the CD4, CD8, and Pan-T antigens. Both cell lines, however, express high levels of viral core and envelope proteins. Paraformaldehyde-inactivated whole virus and similarly inactivated whole-cell virus preparations induced a strong antibody response to core and envelope antigens in immunized cats. The establishment of FIV-producing feline IL-2-independent peripheral blood lymphocyte lines should be valuable for the development of FIV-diagnostic reagents and vaccines and also as a model for human acquired immunodeficiency syndrome vaccine development.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Cats
  • Cell Line*
  • Immunodeficiency Virus, Feline / growth & development*
  • Immunodeficiency Virus, Feline / immunology
  • Immunodeficiency Virus, Feline / isolation & purification
  • Immunodeficiency Virus, Feline / pathogenicity
  • Interleukin-2 / pharmacology
  • Kinetics
  • Lymphocytes / microbiology*
  • Virus Cultivation


  • Interleukin-2