Anti-inflammatory Effect of Alloferon on Ovalbumin-induced Asthma

Asthma is a well-known inflammatory lung disease; however, the specific underlying mechanism is largely unknown. We previously demonstrated that alloferon effectively downregulates pulmonary inflammation. In this study, we examined whether alloferon has a therapeutic effect on asthma. Alloferon remarkably decreased the number of eosinophils, macrophages, and neutrophils in the bronchoalveolar lavage fluid (BALF) from ovalbumin (OVA)-induced asthma mice. It was synergistically decreased with 2.5 mg/kg prednisolone (PDA). Inflammatory cell infiltration around the bronchioles and in the alveolus of OVA-induced asthma mice was effectively prevented by alloferon alone and combined treatment with alloferon and PDS. The production of IL-5 and IL-17 was decreased by alloferon alone and combined treatment with alloferon and PDS. There was no change the level of total immunoglobulin (Ig) following alloferon administration; however, total Ig was decreased by PDS. IgG2a levels were not changed by either alloferon alone or alloferon in combination with PDS. However, the levels of OVA-specific IgG1 and IgE were decreased by alloferon and PDS. In conclusion, our results suggest that a combination of alloferon and prednisolone is effective for the treatment of asthma, as it prevents inflammatory cell infiltration via the down-regulation of IL-5 and IL-17 production and decreases IgG1 and IgE production via the suppression of T helper type 2 immune response.

Alloferon Alleviates Dextran Sulfate Sodium-induced Colitis

Dysfunction of gut immune regulation is involved in mucosal damage in inflammatory bowel disease (IBD). However, there is still no efficacious immune-regulator for the treatment of IBD. Alloferon is a novel immune-modulatory peptide that was originally isolated from infected insects. It shows anti-inflammatory effects by the regulation of cytokine production by immune cells and their activities. Therefore, we investigated the effect of alloferon in a mouse model of colitis using dextran sulfate sodium (DSS). Colitis was induced by administration of DSS in drinking water for 7 consecutive days. It was confirmed by the presence of weight loss, diarrhea, hematochezia, and colon contraction. Alloferon was injected 4 days after DSS administration. We found that alloferon improved the pathogenesis of IBD based on the reduced disease activity index (DAI) and colon contraction. Edema, epithelial erosion, and immune cell infiltration were found in mice administered DSS, but the phenomena were reduced following alloferon treatment. The plasma level of IL-6, a classical pro-inflammatory cytokine in colitis, was also decreased by alloferon. Moreover, alloferon inhibited the TNF-alpha-induced degradation and phosphorylation of IkappaB in Colo205 colon cancer cells. Taken together, these results show that alloferon has anti-inflammatory effects and attenuates DSS-induced colitis.