Monomeric homologue of mammalian CD28 is expressed on chicken T cells

• Published in: The Journal of immunology (1950) Vol. 152; no. 8; pp. 3848 - 3851
• Main Authors: Young, JR, Davison, TF, Tregaskes, CA, Rennie, MC, Vainio, O
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Am Assoc Immnol 15.04.1994; American Association of Immunologists
• Subjects: Amino Acid Sequence; Animals; Biological and medical sciences; CD28 Antigens - classification; CD28 Antigens - metabolism; Chickens - immunology; Cloning, Molecular; DNA, Complementary - genetics; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Humans; Immunobiology; Inbreeding; Lymphoid cells: ontogeny, maturation, markers, receptors, circulation and recirculation; Mice; Molecular Sequence Data; Molecular Weight; Precipitin Tests; Sequence Alignment; Sequence Homology, Amino Acid; T-Lymphocytes - immunology; Human; Rodentia; Monoclonal antibody; Gene expression; Characterization; Vertebrata; Mammalia; Complementary DNA; Mouse; T-Lymphocyte; Evolution; Chicken; Aves; Molecular cloning; Monomer; Comparative study; Aminoacid sequence
• ISSN: 0022-1767; 1550-6606
• DOI: 10.4049/jimmunol.152.8.3848

A mAb recognizing a 40- to 44-kDa monomeric molecule on the surface of chicken T cells was used to screen a cDNA expression library made from Con A-stimulated chicken spleen cells. The sequence of the cDNA obtained encoded a molecule having 50% amino acid sequence identity with mammalian CD28, but the cysteine residue involved in the inter-chain bridge of the mammalian CD28 homodimer was not conserved in the chicken sequence. The molecule produced in transfected COS-7 cells was also recognized by another mAb that had previously been thought to recognize an avian homologue of CD2. The sequence data establish that this molecule is a homologue of mammalian CD28 in the strict evolutionary sense.