Ex Vivo Gene Delivery of IL-1Ra and Soluble TNF Receptor Confers a Distal Synergistic Therapeutic Effect in Antigen-Induced Arthritis

Abstract

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. Retroviral vectors carrying IL-1Ra, sTNFR-Ig, or both genes together were used to stably infect autologous rabbit fibroblasts that were then injected intra-articularly into arthritic rabbit knee joints. The intra-articular delivery of either IL-1Ra- or sTNFR-Ig-expressing fibroblasts was antiinflammatory and chondro-protective in both the injected and noninjected contralateral joints. In addition, we demonstrate that the co-delivery of both antagonists in combination results in a synergistic effect in disease amelioration in both the treated and nontreated joints. These ex vivo results suggest that trafficking of vector-modified inflammatory cells is not the main mechanism responsible for the observed distal spread of the therapeutic effect. Moreover, the results demonstrate that local, ex vivo gene therapy for arthritis could be effective in blocking pathologies within untreated, distant arthritic joints.

Electro-gene therapy of collagen-induced arthritis by using an expression plasmid for the soluble p75 tumor necrosis factor receptor-Fc fusion protein

“…39,40 Recently, it has been reported that local gene transfer could result in a systemic therapeutic effect without systemic elevation of the therapeutic protein. 19,41 Further investigation on the mechanism responsible for these phenomena may help to develop the clinically relevant protocol for electroporation-based gene delivery strategy for the treatment of human RA.…”

Protection against collagen-induced arthritis by intramuscular gene therapy with an expression plasmid for the interleukin-1 receptor antagonist

“…Similar to our observation, it was reported that a contralateral therapeutic effect was achieved even though significant levels (41 ng/ml) of soluble TNFa receptor or IL-1Ra were not detected in animal fluids by ELISA. 36,37 It was suggested that certain kinds of transduced cells might play an important role(s) in contralateral therapeutic effects. 36 Furthermore, it was also reported that dendritic cells could be transfected by intramuscular injection of plasmid DNA and that the transfected dendritic cells could modulate the immune responses.…”

The contralateral effect conferred by intra-articular adenovirus-mediated gene transfer of viral IL-10 is specific to the immunizing antigen

“…The contralateral effect was first observed following injection of adenoviral vectors expressing IL-1and sTNF soluble receptors 7 and has been more recently observed following intra-articular gene transfer of IL-4, 19 FasL, 20 IL-1Ra, 9 and NF-kB decoy oligonucleotides. 10 Hypothetically, the contralateral effect could be conferred by several mechanisms including leakage of virus from the injected joint, generalized immunosuppression due to overexpression of transgene product, migration of genetically modified or functionally altered cells or through a neurogenic pathway.…”

“…8 In addition, the ex vivo gene transfer of IL-1Ra and soluble TNF-a receptor either alone or in combination using genetically modified autologous synovial fibroblasts transplanted intra-articularly was shown to confer a contralateral effect in contralateral control joints, demonstrating that the remedial effects conferred to distant joints do not require direct in vivo delivery of genes. 9 In addition, administration of NF-kB deoxyoligonucleotides/liposome complexes into rat knee joints, able to block TNF and IL-1 expression by macrophages and dendritic cells (DC), conferred a contralateral therapeutic effect in untreated inflamed knee joints. 10 Taken together, these results suggest that the contralateral effect is not restricted to any particular delivery vector, anti-inflammatory/immunosuppressive gene product or arthritis model.…”