Differential expression of U2AF35 in the arthritic joint of avian reovirus-infected chicks.
To identify cell types and genes that are differentially expressed during immunopathogenesis of avian reovirus (ARV)-induced viral arthritis (VA), we inoculated arthrotropic strain S1133 of ARV into 1-day-old broilers, and examined tissue histology as well as RNA expression at different days post-inoculation (PI). Using immunohistochemical staining, we detected many CD68 expressing macrophages in and around the blood vessels of the arthritic joints. By RT-PCR, we found that expression of matrix metalloproteinase-2 (MMP-2) and bone morphogenetic protein-2 (BMP-2) was induced earlier in footpads and hock joints of ARV-infected chickens. By employing suppression subtractive hybridization (SSH) technique and RT-PCR, we further identified that small subunit of U2 snRNP auxiliary factor (U2AF35 or U2AF1) mRNA was differentially induced in the joint of ARV-infected chickens. By in situ hybridization (ISH), mRNA signals of U2AF35 and BMP-2 were located in chondrocytes within/near the epiphyseal plate and secondary center of ossification, and in epidermal cells and dermal fibroblast-like cells of arthritic joints. In addition, U2AF35 mRNA was expressed in the inflammatory infiltrates of the bone marrow of ARV-infected arthritic joints, while MMP-2 was mainly detected in chondrocytes. Interestingly, among U2AF35, MMP-2, and BMP-2 that were differentially expressed in the joint of ARV-infected chickens, only U2AF35 induction correlated well with arthritic manifestation. Because U2AF35 may assist in mRNA splicing of proinflammatory chemokines and cytokines, our results indicated that U2AF35 induction might play an immunopathological role in ARV-induced arthritis. This study has first associated U2AF35 to viral arthritis.
Fan
Yi-Hsin
YH
Graduate Institute of Veterinary Microbiology, National Chung Hsing University, 250 Kuo Kuang Road, Taichung 40227, Taiwan, ROC.
Lin
Chun-Da
CD
Chiou
Shiow-Her
SH
Chow
Kuan-Chih
KC
Chi
Yung-Sheng
YS
Lee
Long-Huw
LH
Shien
Jui-Hung
JH
Shieh
Happy K
HK
D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D001170:Arthritis, Infectious / Q000276:immunology / Q000473:pathology / Q000662:veterinary* / Q000821:virology; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology; D002645:Chickens; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D005786:Gene Expression Regulation; D007150:Immunohistochemistry / Q000662:veterinary; D017403:In Situ Hybridization / Q000662:veterinary; D007596:Joints / Q000276:immunology / Q000473:pathology; D020778:Matrix Metalloproteinase 2 / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology; D009687:Nuclear Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D030101:Orthoreovirus, Avian / Q000276:immunology*; D011201:Poultry Diseases / Q000235:genetics / Q000276:immunology / Q000473:pathology / Q000821:virology*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012088:Reoviridae Infections / Q000276:immunology / Q000473:pathology / Q000662:veterinary* / Q000821:virology; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D012261:Ribonucleoproteins / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D013047:Specific Pathogen-Free Organisms; D000072668:Splicing Factor U2AF; D016212:Transforming Growth Factor beta / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology
D000914:Antibodies, Viral; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D009687:Nuclear Proteins; D012333:RNA, Messenger; D012261:Ribonucleoproteins; D000072668:Splicing Factor U2AF; D016212:Transforming Growth Factor beta; D020778:Matrix Metalloproteinase 2