title: Isolation and characterization of lymphocyte-like cells from a lamprey.
abstract: Lymphocyte-like cells in the intestine of the sea lamprey, Petromyzon marinus, were isolated by flow cytometry under light-scatter conditions used for the purification of mouse intestinal lymphocytes. The purified lamprey cells were morphologically indistinguishable from mammalian lymphocytes. A cDNA library was prepared from the lamprey lymphocyte-like cells, and more than 8,000 randomly selected clones were sequenced. Homology searches comparing these ESTs with sequences deposited in the databases led to the identification of numerous genes homologous to those predominantly or characteristically expressed in mammalian lymphocytes, which included genes controlling lymphopoiesis, intracellular signaling, proliferation, migration, and involvement of lymphocytes in innate immune responses. Genes closely related to those that in gnathostomes control antigen processing and transport of antigenic peptides could be ascertained, although no sequences with significant similarity to MHC, T cell receptor, or Ig genes were found. The data suggest that the evolution of lymphocytes in the lamprey has reached a stage poised for the emergence of adaptive immunity.
authors.affiliation: Max-Planck-Institut für Biologie, Abteilung Immungenetik, Corrensstrasse 42, D-72076 Tübingen, Germany.
authors.forename: Werner E
authors.initials: WE
authors.lastname: Mayer
authors.forename: Tatiana
authors.initials: T
authors.lastname: Uinuk-Ool
authors.forename: Herbert
authors.initials: H
authors.lastname: Tichy
authors.forename: Lanier A
authors.initials: LA
authors.lastname: Gartland
authors.forename: Jan
authors.initials: J
authors.lastname: Klein
authors.forename: Max D
authors.initials: MD
authors.lastname: Cooper
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics; D000818:Animals; D015415:Biomarkers; D002455:Cell Division; D002465:Cell Movement; D003546:Cysteine Endopeptidases / Q000235:genetics; D020224:Expressed Sequence Tags; D015870:Gene Expression; D020869:Gene Expression Profiling; D007798:Lampreys; D008214:Lymphocytes / Q000145:classification / Q000166:cytology* / Q000378:metabolism; D051379:Mice; D009097:Multienzyme Complexes / Q000235:genetics; D046988:Proteasome Endopeptidase Complex; D015398:Signal Transduction / Q000235:genetics
chemical_list: D018528:ATP-Binding Cassette Transporters; D015415:Biomarkers; D009097:Multienzyme Complexes; D003546:Cysteine Endopeptidases; D046988:Proteasome Endopeptidase Complex