Constitutive expression of HIV-VLPs in stably transfected insect cell line for efficient delivery system

We have previously developed HIV-1 Pr55gag-based virus-like particles (HIV-VLPs) as presentation and delivery model using a transient Baculovirus expression system. Here we describe the establishment and characterization of stably transfected insect cell line for the constitutive and reproducible production of HIV-VLPs. The persistence of HIV gag coding gene has been verified in clonal resistant insect cells and the protein expression has been confirmed by Western blot analysis. The resulting HIV-VLPs have been evaluated by standard transmission electron microscopy and their immunogenicity has been evaluated in vivo. Our results demonstrate that this strategy is highly efficient for constitutive expression of conformational enveloped VLPs which can be employed as presentation and delivery system for pathogen as well as tumor-associated antigens. This represents, to our knowledge, the first example of stably transfected insect cell line for the constitutive production of VLPs.