Construction of Recombinant Herpes Simplex Virus Type 1 with α 1b IFN
To study the biological r elevance of using herpes simplex vir uses as a vector for expressing cy tokines,a new kind of recombinant herpes simplex virus type 1(HSV1) that expressed human interferon α1 bIFN was constructedBased on a se t of cosmids containing the entire HSV1 genome,the α1bIFN expression bo x (the α1bIFN gene was placed under the control of the HCMV promoter) was inserted into HSV1 UL2 gene on cosmid 6 to generate cos6/α1bIFNBy co-transfecting cos6/α1bIFN with the other cosmids such as cosmid28,cos mid14,cosmid56 and cosmid48,HSV1-α 1bIFN/△UL2 was generated in the cell s by recombinationTo evaluate α1bIFN expression,vector infected cell cu lture media were assayed for α1bIF N releaseIn vitro characterizatio n of the recombinant interferon-α 1bIFN confirmed that the α1bIFN ex pressed in HSV1 infected cells was biologically activeThese cells di d not secrete detectable levels of α1bIFN when infected with control virusesCells infected at a multip licity of infection of 10 with HSV-α 1bIFN/△UL2 produced approximately 2 8×104IU/ml α1bIFN in 24 hrs,as de termined by a standard vecicular s tomatitis virus(VSV) replication inhibition assay. These vectors should be useful for in vivo analysis of the antiviral potential of α1bIFN ex pression from within the nervous system