Molecular and functional characterization of chicken IL-15.
A cDNA encoding chicken interleukin-15 was cloned from a CD4+ T cell hybridoma expression library by screening with a rabbit antibody against a protein fraction of conditioned medium containing T cell growth promoting activity. The chicken IL-15 cDNA contains an open reading frame of 143 amino acids with a single potential N-linked glycosylation site. The predicted m.w. of the encoded protein (16 kDa) matched the size of an immunoreactive band on Western blots of E. coli expressing the recombinant IL-15. Amino acid and nucleotide sequence analyses of chicken IL-15 revealed 31% and 46% identity with bovine IL-15 respectively and lesser homologies to other mammalian IL-15s. Chicken IL-15 contained all 4 highly conserved cysteine residues present in mammalian IL-15 sequences. RT-PCR demonstrated that the chicken IL-15 gene is expressed in many tissues including spleen, intestine, and muscle and in established macrophage, T lymphoma and fibroblast cell lines. Activation of spleen cells with Con A enhanced the expression of IL-15 gene transcripts in a time-dependent manner. CHO-K1 cells transfected with the chicken IL-15 cDNA secreted a biologically active protein supporting the growth of Con A activated spleen lymphocytes. Continuous culture of spleen Con A lymphoblasts with chicken IL-15 over two months resulted in an enriched T lymphocyte population expressing the gammadeltaTCR, CD8alpha, and CD3 cell surface antigens.
Choi
K D
KD
Immunology and Disease Resistance Laboratory, Livestock and Poultry Sciences Institute, USDA, Beltsville, MD 20705, USA.
Lillehoj
H S
HS
Song
K D
KD
Han
J Y
JY
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D016466:CHO Cells; D002417:Cattle; D002645:Chickens; D003001:Cloning, Molecular; D006224:Cricetinae; D018076:DNA, Complementary; D006801:Humans; D019409:Interleukin-15 / Q000235:genetics* / Q000276:immunology*; D008969:Molecular Sequence Data; D012333:RNA, Messenger; D011817:Rabbits; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000276:immunology; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D014018:Tissue Distribution
D018076:DNA, Complementary; D019409:Interleukin-15; D012333:RNA, Messenger; D016692:Receptors, Antigen, T-Cell, gamma-delta