TY - JOUR
T1 - Co-expression of insulin-like growth factor-1 and interleukin-4 in an in vitro inflammatory model
AU - Manning, Kizzie
AU - Rachakonda, P. Sivaramakrishna
AU - Rai, Muhammad Farooq
AU - Schmidt, Michael F.G.
PY - 2010/6
Y1 - 2010/6
N2 - The ailment osteoarthritis (OA) has two aspects - inflammation and cartilage degradation - where combined transgene expression may offer an effective gene therapy. Our present study focuses on the co-expression of interleukin-4 (IL-4) and insulin-like-growth factor-1 (IGF-1), which specifically target inflammation and cartilage repair, respectively. In this study, we analyze the expression of IGF-1 and IL-4 from a single plasmid vector, where each gene is expressed through an independent promoter and enhancer sequence. Regenerative and anti-inflammatory effects of IGF-1 alone and of both IGF-1 and IL-4 were analyzed in an in vitro chondrocyte inflammatory model. Co-expression of both transgenes in primary chondrocytes was ascertained by immunoassays. Following stimulation with IL-1β and TNFα, pro-inflammatory mediators as well as IGF-binding proteins were down-regulated more effectively in the presence of both genes to levels comparable to the non-stimulated control. Further, cartilage regeneration proteins type II collagen and proteoglycans were up-regulated in stimulated cells transfected with IGF-1 alone and in combination with IL-4. The co-expression of IGF-1 and IL-4 shows that both transgenes complement each other by effectively triggering cartilage regeneration and reducing inflammation. Use of combinatorial transgene expression offers a promising avenue in the area of gene therapy in OA.
AB - The ailment osteoarthritis (OA) has two aspects - inflammation and cartilage degradation - where combined transgene expression may offer an effective gene therapy. Our present study focuses on the co-expression of interleukin-4 (IL-4) and insulin-like-growth factor-1 (IGF-1), which specifically target inflammation and cartilage repair, respectively. In this study, we analyze the expression of IGF-1 and IL-4 from a single plasmid vector, where each gene is expressed through an independent promoter and enhancer sequence. Regenerative and anti-inflammatory effects of IGF-1 alone and of both IGF-1 and IL-4 were analyzed in an in vitro chondrocyte inflammatory model. Co-expression of both transgenes in primary chondrocytes was ascertained by immunoassays. Following stimulation with IL-1β and TNFα, pro-inflammatory mediators as well as IGF-binding proteins were down-regulated more effectively in the presence of both genes to levels comparable to the non-stimulated control. Further, cartilage regeneration proteins type II collagen and proteoglycans were up-regulated in stimulated cells transfected with IGF-1 alone and in combination with IL-4. The co-expression of IGF-1 and IL-4 shows that both transgenes complement each other by effectively triggering cartilage regeneration and reducing inflammation. Use of combinatorial transgene expression offers a promising avenue in the area of gene therapy in OA.
KW - Arthritis
KW - IGF-1
KW - IL-4
KW - Inflammation
KW - Pro-inflammatory cytokines
UR - http://www.scopus.com/inward/record.url?scp=77952541151&partnerID=8YFLogxK
U2 - 10.1016/j.cyto.2010.01.010
DO - 10.1016/j.cyto.2010.01.010
M3 - Article
C2 - 20188584
AN - SCOPUS:77952541151
VL - 50
SP - 297
EP - 305
JO - Cytokine
JF - Cytokine
SN - 1043-4666
IS - 3
ER -