Polyethylenimine-based antisense oligodeoxynucleotides of IL-4 suppress the production of IL-4 in a murine model of airway inflammation.
BACKGROUND
Interleukin-4 (IL-4) plays a crucial role as an inflammatory mediator in allergic asthma via inducing Th2 inflammation and IgE synthesis. To develop an effective therapeutic agent which specifically inhibits production of IL-4, antisense oligodeoxynucleotides (AS-ODNs) against murine IL-4 mRNA were generated and complexed with polyethylenimine (PEI) to improve intracellular delivery.


METHODS
AS-ODNs were generated against the translation initiation region of murine IL-4 mRNA, and complexed with linear PEI. In vitro efficacy of AS-ODNs/PEI complexes was tested by measuring IL-4 production in the D10.G4.1 cell line, and cytotoxicity was tested by XTT assay. Physicochemical properties of polyplexes were examined using atomic force microscopy (AFM) and DNase I protection assay. In vivo effects of IL-4 AS-ODNs/PEI complexes were tested in a murine model of airway inflammation. IL-4 concentrations in the bronchoalveolar lavage (BAL) fluid and circulating IgE levels were measured by ELISA, and histological analysis of lung tissues was performed.


RESULTS
IL-4 AS-ODNs/PEI complexes were spheres with an average diameter of 98 nm and resistant to DNase I-mediated degradation. IL-4 AS-ODNs/PEI complexes showed up to 35% inhibition of IL-4 production in D10.G4.1 cells without causing any toxicity, while naked ODNs gave less than 1% reduction. Furthermore, IL-4 AS-ODNs/PEI complexes were effective in suppressing secretion of IL-4 (up to 30% reduction) in the BAL fluid in an ovalbumin-sensitized murine model of airway inflammation. Circulating IgE levels were decreased, and airway inflammation was alleviated by treatment with IL-4 AS-ODNs polyplexes.


CONCLUSIONS
These data demonstrate that complexation of IL-4 AS-ODNs with PEI provides a potential therapeutic tool in controlling inflammation associated with allergic asthma, and further presents an opportunity to the development of clinical therapy based on combination of multiple AS-ODNs of cytokines and/or signaling effectors involved in Th2 inflammation and eosinophilia.
Seong
Ji-Hye
JH
National Research Laboratory for Drug and Gene Delivery, College of Pharmacy, Seoul National University, Seoul, Korea 151-742.
Lee
Kyung-Mi
KM
Kim
Sung Tae
ST
Jin
Su-Eon
SE
Kim
Chong-Kook
CK
D000818:Animals; D001249:Asthma / Q000235:genetics / Q000276:immunology* / Q000628:therapy; D002460:Cell Line; D004195:Disease Models, Animal; D004797:Enzyme-Linked Immunosorbent Assay; D004802:Eosinophilia; D005260:Female; D007249:Inflammation; D015847:Interleukin-4 / Q000096:biosynthesis*; D051379:Mice; D008807:Mice, Inbred BALB C; D016376:Oligonucleotides, Antisense / Q000276:immunology* / Q000627:therapeutic use*; D011094:Polyethyleneimine; D012333:RNA, Messenger; D012137:Respiratory System / Q000276:immunology
D016376:Oligonucleotides, Antisense; D012333:RNA, Messenger; D015847:Interleukin-4; D011094:Polyethyleneimine