Interferon-λ3 alleviates intestinal epithelium injury induced by porcine rotavirus in mice.

Interferons are a group of glycoproteins that are expressed in various cell types in their inflammatory responses to infections. In this study, we explored the protective effects of porcine interferon-λ3 (PIFN-λ3) on intestinal inflammation and injury in mice induced by porcine rotavirus (PRV). BALB/c mice were administrated by PIFN-λ3 or phosphate buffer solution (PBS) for three days prior to PRV infection. We show that PRV infection caused acute inflammatory responses in mice, as indicated by increases in serum concentrations of inflammatory cytokines such as the interlukin-1β (IL-1β), interlukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) (P < 0.05). However, PIFN-λ3 administration not only decreased their concentrations but also elevated the concentrations of immunoglobulin (Ig) M and IgG in the PRV challenged mice (P < 0.05). PRV infection significantly decreased the jejunal villus height and the ratio of villus height to crypt depth (V/C); however, PIFN-λ3 treatment significantly elevated the villus height and the abundance of tight junction protein ZO-1 in the jejunum (P < 0.05). Moreover, PIFN-λ3 decreased the replication of PRV in the jejunal epithelium, but significantly increased the abundance of sIgA and the activities of maltase and sucrase in the PRV-challenged mice (P < 0.05). Interestingly, PIFN-λ3 elevated the expression levels of sodium/glucose cotransporter 1 (SGLT1) and mucin 2 (MUC2) in the PRV-challenged mice (P < 0.05). Moreover, PIFN-λ3 significantly increased the expression levels of IL-10, signal transducer and activator of transcription 1 (STAT1), and critical interferon-stimulated genes such as the 2'-5' oligoadenylate synthetase-like 1 (OASL1), interferon-induced protein with tetratricopeptide repeats 1 (IFIT1) and radical S-adenosyl methionine domain containing 2 (RSAD2) in the jejunum upon PRV infection (P < 0.05). The anti-virus and anti-inflammatory effect of PIFN-λ3 should make it an attractive candidate to prevent various pathogen-induced bowel diseases.