Inhibition of GM-CSF/IL-3/IL-5 Signaling by Antisense Oligodeoxynucleotides Targeting the Common Beta Chain of Their Receptors

Abstract

Granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-3 (IL-3), and IL-5 play a key role in allergic inflammation. They mediate their effect via receptors that consist of two distinct subunits, a cytokine-specific alpha subunit and a common beta subunit (βc) that transduces cell signaling. We sought to downregulate the biologic activities of GM-CSF, IL-3, and IL-5 simultaneously by inhibiting βc mRNA expression with antisense technology. Experiments were performed with TF-1 cells (a human erythroleukemia cell line expressing GM-CSF, IL-3, and IL-5 receptors, which proliferates in response to these cytokines), monocytic U937 cells, which require these cytokines for differentiation, and purified human eosinophils. Cells were treated with antisense phosphorothioate oligodeoxynucleotides (ODN) targeting βc mRNA. In contrast to nontreated cells and cells treated by sense or mismatched ODN, antisense ODN inhibited βc mRNA expression and significantly decreased the level of cell surface βc protein expression on TF-1 and U937 cells. Receptor function was also affected. Antisense ODN were able to inhibit TF-1 cell proliferation in vitro in the presence of GM-CSF, IL-3, or IL-5 in the culture medium and eosinophil survival. We suggest that antisense ODN against βc may provide a new therapeutic alternative for the treatment of neoplastic or allergic diseases associated with eosinophilic inflammation.