APPLICANT'S DESCRIPTION: In the prior years of the Program, the Vector Core has produced retroviral vectors for each of the projects. We have also gained proficiency in the design, construction and packaging of HIV-1 based lentiviral vectors. The Vector core will use current state-of-the-art vectors and packaging systems to design, construct, package and perform initial characterization of retroviral and lentiviral vectors for investigators of the Projects to pursue their scientific objectives.