Hyperactive Himar1 transposase mediates transposition in cell culture and enhances gene expression in vivo.

The use of nonviral delivery systems results in transient gene expression, in part because of the low efficiency of DNA integration. Previously, vectors based on transposon systems such as Sleeping Beauty have been shown to be able to increase stable transfection efficiencies in cell culture and in animal models. Himar1, a reconstructed active transposon belonging to the Tc1/mariner superfamily, also has been used as a vector for stable gene delivery, but the rate of transposition after transfection is low.

PhiC31 integrase mediates integration in cultured synovial cells and enhances gene expression in rabbit joints.

Background: Gene transfer to synovium in joints has been shown to be an effective approach for treating pathologies associated with rheumatoid arthritis (RA) and related joint disorders. However, the efficiency and duration of gene delivery has been limiting for successful gene therapy for arthritis. The transient gene expression that often accompanies non-viral gene delivery can be prolonged by integration of vector DNA into the host genome.

Human, viral or mutant human IL-10 expressed after local adenovirus-mediated gene transfer are equally effective in ameliorating disease pathology in a rabbit knee model of antigen-induced arthritis.

IL-10 is a Th2 cytokine important for inhibiting cell-mediated immunity while promoting humoral responses. Human IL-10 (hIL-10) has anti-inflammatory, immunosuppressive as well as immunostimulatory characteristics, whereas viral IL-10 (vIL-10), a homologue of hIL-10 encoded by Epstein Barr virus (EBV), lacks several immunostimulatory functions. The immunostimulatory characteristic of hIL-10 has been attributed to a single amino acid, isoleucine at position 87, which in vIL-10 is alanine.

Exosomes derived from IL-10-treated dendritic cells can suppress inflammation and collagen-induced arthritis.

We have demonstrated previously that local, adenoviral-mediated gene transfer of viral IL-10 to a single joint of rabbits and mice with experimental arthritis can suppress disease in both the treated and untreated contralateral joints. This contralateral effect is mediated in part by APCs able to traffic from the treated joint to lymph nodes as well as to untreated joints. Moreover, injection of dendritic cells (DC) genetically modified to express IL-4 or Fas ligand was able to reverse established murine arthritis.

Ex vivo gene delivery of IL-1Ra and soluble TNF receptor confers a distal synergistic therapeutic effect in antigen-induced arthritis.

Intra-articular expression of antagonists of interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) in arthritic rabbit knee and mouse ankle joints by direct adenoviral-mediated intraarticular delivery results in amelioration of disease pathology in both the treated and contralateral untreated joints. Previous experiments suggest that direct adenoviral infection of resident antigen-presenting cells (APCs) and subsequent traveling of these cells to other sites of inflammation and lymph nodes might be responsible for this "contralateral effect." To determine whether genetic modification of APCs is required for the contralateral effect, we have used an ex vivo approach utilizing genetically modified fibroblasts to express IL-1 receptor antagonist protein (IL-1Ra) and soluble TNF-alpha receptor (sTNFR) locally in arthritic joints.