title: Involvement of TLR21 in baculovirus-induced interleukin-12 gene expression in avian macrophage-like cell line HD11.
abstract: Our previous work showed that baculovirus (Antheraea pernyi nuclear polyhedrosis virus [ApNPV]) induced a strong innate immunity and protected chicken from a lethal challenge of bronchitis virus. The purpose of present study was to determine the chicken Toll-like receptors (TLRs) used by BV-infected immune cells to induce this immune response. We first investigated the expression of the Toll-like receptor (TLR) genes in resting and BV-infected HD11 (chicken macrophage-like cell line) and DT40 (chicken B cell-like cell line) cells. Expressions of TLRs were detected in both cell types. After BV stimulation, TLR21 was the only upregulated TLR in HD11 cells, and all the TLRs were down-regulated in DT40 cells. Since TLR activation generally leads to cytokine induction, we then determined the expression of IL-12 in the two cell lines following treatment with BV or oligodeoxynucleotides (ODN) containing CpG dinucleotides (CpG-ODN). BV and CpG-ODN treatment induced the expression of IL-12 in HD11 but not in DT40 cells. HD11 cells transfected with siRNA specific for TLR21 significantly diminished BV- and CpG-ODN-induced IL-12 expression. Therefore, BV and CpG-ODN stimulated IL-12 expression involved TLR21 signaling and chicken TLR21 may have similar functions to the mammalian TLR9.
authors.affiliation: School of Environmental & Biological Science & Technology, Dalian University of Technology, RP116023, Dalian, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Han
authors.forename: Mingshan
authors.initials: M
authors.lastname: Niu
authors.forename: Lijia
authors.initials: L
authors.lastname: An
authors.forename: Wenli
authors.initials: W
authors.lastname: Li
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D016367:Baculoviridae / Q000187:drug effects / Q000235:genetics* / Q000276:immunology; D001483:Base Sequence; D002460:Cell Line; D002645:Chickens / Q000235:genetics / Q000276:immunology; D017931:DNA Primers; D005786:Gene Expression Regulation; D055785:Gene Knockdown Techniques; D020868:Gene Silencing; D018664:Interleukin-12 / Q000235:genetics*; D008264:Macrophages / Q000187:drug effects / Q000276:immunology*; D009838:Oligodeoxyribonucleotides / Q000737:chemistry; D034741:RNA, Small Interfering / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D051193:Toll-Like Receptors / Q000235:genetics* / Q000276:immunology; D015854:Up-Regulation
chemical_list: D000900:Anti-Bacterial Agents; D017931:DNA Primers; D009838:Oligodeoxyribonucleotides; D034741:RNA, Small Interfering; D051193:Toll-Like Receptors; D018664:Interleukin-12