title: Cloning and functional characterization of chicken stem cell antigen 2.
abstract: Stem cell antigen 2 (SCA2) is a Ly6 family member whose function is largely unknown. To characterize biological properties and tissue distribution of chicken SCA2, SCA2 was expressed in E. coli, purified, and a polyclonal antibody developed. Utilizing the polyclonal antibody, SCA2 is a 13 kDa cell surface protein anchored by a glycosyl-phosphatidylinositol (GPI) moiety. SCA2 is expressed in connective tissues of thymus and bursa based on immunohistochemistry, immunoprecipitation, and western blots. In bursal follicles, SCA2 is specifically expressed on the cortical-medullary epithelial cells (CMEC) surrounded by MHC class II presenting cells. Expression profiles of bursal cells induced by contact with SCA2-expressing cells shows down-regulation of numerous genes including CD79B, B cell linker (BLNK), spleen tyrosine kinase (SYK), and gamma 2-phospholipase C (PLCG2) that are involved in the B cell receptor (BCR) and immune response signaling pathways. These results suggest chicken SCA2 plays a role in regulating B lymphocytes.
authors: United States Department of Agriculture, Agricultural Research Service, Avian Disease and Oncology Laboratory, 3606 E. Mount Hope Rd., East Lansing, MI 48823, USA.
authors: Weifeng
authors: W
authors: Mao
authors: Henry D
authors: HD
authors: Hunt
authors: Hans H
authors: HH
authors: Cheng
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology / Q000378:metabolism; D015153:Blotting, Western; D002469:Cell Separation; D002645:Chickens / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D003001:Cloning, Molecular; D005434:Flow Cytometry; D005786:Gene Expression Regulation; D007150:Immunohistochemistry; D047468:Immunoprecipitation; D008565:Membrane Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D008969:Molecular Sequence Data; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000276:immunology*
chemical_list: D008565:Membrane Proteins; C084839:thymic shared antigen-1