title: Establishing Restricted Expression of Caveolin-1 in HIV Infected Cells and Inhibition of Virus Replication.
abstract: BACKGROUND
  Caveolin-1 (Cav-1) is the major protein of the caveolae and plays a role in multiple cellular functions and implicated to have anti-HIV activity. Regulated expression of Cav-1 is important for safe and effective use in order to exploit Cav-1 for HIV therapeutic applications.
  
  
  METHODS
  A series of Cav-1 and GFP expression vectors were constructed under the control of the HIV LTR for conditional expression or CMV promoter and the expression of Cav-1 was monitored in the presence or absence of Tat or HIV infection in order to establish the restricted expression of Cav-1 to HIV infected cells.
  
  
  RESULTS
  Cav-1 expression was evident under the control of the HIV LTR in the absence of Tat or HIV infection as demonstrated by immunoblot. Placing two internal ribosomal entry sequences (IRES) and a Rev response element, RRE (5'~ LTR-IRES-GFP-RRE-IRES-Cav-1~3') resulted in no expression of Cav-1 in the absence of Tat with effective expression in the presence of Tat. Transduction of HIV permissive cells with this construct using a foamy virus vector show that Cav-1 was able to inhibit HIV replication by 82%. Cells that received LTR-IRES-GFP-RRE-IRES-Cav-1 remain healthy in the absence of Tat or HIV infection.
  
  
  CONCLUSIONS
  These results taken together reveal the inclusion of two IRES establishes a significant reduction of leak through expression of Cav-1 in the absence of Tat or HIV infection. Such regulated expression will have therapeutic application of Cav-1 for HIV infection as well as broad applications which can be beneficial for other host-targeted interventions as therapeutics.
authors.affiliation: Department of Infectious Disease and Pathology, University of Florida, Gainesville, FL 32611, USA.
authors.forename: Yung-Tsun
authors.initials: YT
authors.lastname: Lo
authors.affiliation: Department of Infectious Disease and Pathology, University of Florida, Gainesville, FL 32611, USA.
authors.forename: Peter E
authors.initials: PE
authors.lastname: Nadeau
authors.affiliation: Department of Infectious Disease and Pathology, University of Florida, Gainesville, FL 32611, USA.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Lin
authors.affiliation: Department of Infectious Disease and Pathology, University of Florida, Gainesville, FL 32611, USA.
authors.forename: Ayalew
authors.initials: A
authors.lastname: Mergia
keywords: Caveolin-1; HIV; LTR; Tat.