title: The expressed TCRβ CDR3 repertoire is dominated by conserved DNA sequences in channel catfish.
abstract: We analyzed by high-throughput sequencing T cell receptor beta CDR3 repertoires expressed by αβ T cells in outbred channel catfish before and after an immunizing infection with the parasitic protozoan Ichthyophthirius multifiliis. We compared CDR3 repertoires in caudal fin before infection and at three weeks after infection, and in skin, PBL, spleen and head kidney at seven and twenty-one weeks after infection. Public clonotypes with the same CDR3 amino acid sequence were expressed by αβ T cells that underwent clonal expansion following development of immunity. These clonally expanded αβ T cells were primarily located in spleen and skin, which is a site of infection. Although multiple DNA sequences were expected to code for each public clonotype, each public clonotype was predominately coded by an identical CDR3 DNA sequence in combination with the same J gene in all fish. The processes underlying this shared use of CDR3 DNA sequences are not clear.
authors.affiliation: Department of Infectious Diseases, College of Veterinary Medicine, The University of Georgia, Athens, GA 30602, USA. Electronic address: rfindly@uga.edu.
authors.forename: R Craig
authors.initials: RC
authors.lastname: Findly
authors.affiliation: Department of Infectious Diseases, College of Veterinary Medicine, The University of Georgia, Athens, GA 30602, USA. Electronic address: fdn452@uga.edu.
authors.forename: Frank D
authors.initials: FD
authors.lastname: Niagro
authors.affiliation: Department of Infectious Diseases, College of Veterinary Medicine, The University of Georgia, Athens, GA 30602, USA. Electronic address: hwd@uga.edu.
authors.forename: Harry W
authors.initials: HW
authors.lastname: Dickerson
mesh_terms: D000818:Animals; D049109:Cell Proliferation; D016798:Ciliophora / Q000276:immunology*; D016770:Ciliophora Infections / Q000276:immunology*; D060966:Clonal Selection, Antigen-Mediated; D002999:Clone Cells; D022801:Complementarity Determining Regions / Q000235:genetics*; D005393:Fish Diseases / Q000276:immunology*; D029941:Fish Proteins / Q000235:genetics*; D059014:High-Throughput Nucleotide Sequencing; D007059:Ictaluridae / Q000276:immunology*; D008213:Lymphocyte Activation; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000235:genetics*; D013601:T-Lymphocytes / Q000502:physiology*
chemical_list: D022801:Complementarity Determining Regions; D029941:Fish Proteins; D016693:Receptors, Antigen, T-Cell, alpha-beta
keywords: CDR3 repertoire; High-throughput DNA sequencing; T cell receptor; Teleost