title: Combinations of CD45 isoforms are crucial for immune function and disease.
abstract: Expression of the CD45 Ag in hemopoietic cells is essential for normal development and function of lymphocytes, and both mice and humans lacking expression exhibit SCID. Human genetic variants of CD45, the exon 4 C77G and exon 6 A138G alleles, which alter the pattern of CD45 isoform expression, are associated with autoimmune and infectious diseases. We constructed transgenic mice expressing either an altered level or combination of CD45 isoforms. We show that the total level of CD45 expressed is crucial for normal TCR signaling, lymphocyte proliferation, and cytokine production. Most importantly, transgenic lines with a normal level, but altered combinations of CD45 isoforms, CD45(RABC/+) and CD45(RO/+) mice, which mimic variant CD45 expression in C77G and A138G humans, show more rapid onset and increased severity of experimental autoimmune encephalomyelitis. CD45(RO/+) cells produce more TNF-alpha and IFN-gamma. Thus, for the first time, we have shown experimentally that it is the combination of CD45 isoforms that affects immune function and disease.
authors.affiliation: The Edward Jenner Institute for Vaccine Research, Compton, Berkshire RG20 7NN, United Kingdom.
authors.forename: Ritu
authors.initials: R
authors.lastname: Dawes
authors.forename: Svetla
authors.initials: S
authors.lastname: Petrova
authors.forename: Zhe
authors.initials: Z
authors.lastname: Liu
authors.forename: David
authors.initials: D
authors.lastname: Wraith
authors.forename: Peter C L
authors.initials: PC
authors.lastname: Beverley
authors.forename: Elma Z
authors.initials: EZ
authors.lastname: Tchilian
mesh_terms: D000818:Animals; D049109:Cell Proliferation; D002478:Cells, Cultured; D016207:Cytokines / Q000096:biosynthesis; D004681:Encephalomyelitis, Autoimmune, Experimental / Q000139:chemically induced / Q000276:immunology* / Q000378:metabolism / Q000473:pathology*; D017493:Leukocyte Common Antigens / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D008213:Lymphocyte Activation / Q000276:immunology; D051379:Mice; D008822:Mice, Transgenic; D009185:Myelin Proteins; D018992:Myelin-Associated Glycoprotein / Q000494:pharmacology; D063308:Myelin-Oligodendrocyte Glycoprotein; D010446:Peptide Fragments / Q000494:pharmacology; D020033:Protein Isoforms / Q000172:deficiency / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism
chemical_list: D016207:Cytokines; C571326:MOG protein, human; C571327:Mog protein, mouse; D009185:Myelin Proteins; D018992:Myelin-Associated Glycoprotein; D063308:Myelin-Oligodendrocyte Glycoprotein; D010446:Peptide Fragments; D020033:Protein Isoforms; D017493:Leukocyte Common Antigens