Lentivirus

Feline Immunodeficiency Virus (FIV) Based Vectors

  • Infects dividing and non-dividing cells.
  • Long term, stable gene expression resulting from genomic integration.
  • Potential for pseudotyping with a wide variety of viral envelope glycoproteins that broaden cell tropism/specificity.
  • Viral titers typically range from 1x107 TU/ml to 5x108 TU/ml (transducing units). Factors such as expression cassette size or choice of envelope will influence titer.
  • FIV encodes for no viral proteins and typically innate or adaptive immune responses are minimal as compared to adenoviral vectors.
  • FIV accommodates insert sizes of 6.5 kb. Larger expression cassettes can be packaged but decreases in titers will be expected.

Human Immunodeficiency Virus (HIV) Based Vectors

  • Infects dividing and non-dividing cells.
  • Long term, stable gene expression resulting from genomic integration.
  • Potential for pseudotyping with a wide variety of viral envelope glycoproteins that broaden cell tropism/specificity.
  • Vector titers typically range from 1x107 TU/ml to 5x108 TU/ml. Factors such as expression cassette size or choice of envelope will influence titer.
  • HIV encodes for no viral proteins and typically innate or adaptive immune responses are minimal as compared to adenoviral vectors.
  • HIV accommodates insert sizes of 6.5 kb. Larger expression cassettes can be packaged but decreases in titers will be expected.

Moloney Murine Leukemia Retrovirus (mMLV) Based Vectors

  • Broad cell tropism.
  • Transduces dividing cells.
  • Titers typically range from 106–107 TU/ml.
  • Stable gene expression due to viral genome integration.
  • mMLV accommodates insert sizes of 6.5 kb. Larger expression cassettes can be packaged but decreases in titers will be expected.

Further information about the differences between the lentiviral or retroviral vectors can be found here.