title: A Leukocyte Immune-Type Receptor Subset Is a Marker of Antiviral Cytotoxic Cells in Channel Catfish, Ictalurus punctatus.
abstract: Channel catfish, Ictalurus punctatus, leukocyte immune type receptors (LITRs) represent a multigene family that encodes Ig superfamily proteins that mediate activating or inhibitory signaling. In this study, we demonstrate the use of mAb CC41 to monitor viral cytotoxic responses in catfish and determine that CC41 binds to a subset of LITRs on the surface of catfish clonal CTLs. Homozygous gynogenetic catfish were immunized with channel catfish virus (CCV)-infected MHC-matched clonal T cells (G14D-CCV), and PBL were collected at various times after immunization for flow cytometric analyses. The percentage of CC41(+) cells was significantly increased 5 d after primary immunization with G14D-CCV and at 3 d after a booster immunization as compared with control fish only injected with G14D. Moreover, CC41(+) cells magnetically isolated from the PBL specifically killed CCV-infected targets as measured by (51)Cr release assays and expressed messages for CD3γδ, perforin, and at least one of the CD4-like receptors as analyzed by RNA flow cytometry. When MLC effector cells derived from a G14D-CCV-immunized fish were preincubated with CC41 mAb, killing of G14D-CCV targets was reduced by ∼40%, suggesting that at least some LITRs have a role in target cell recognition and/or cytotoxicity. The availability of a LITR-specific mAb has allowed, to our knowledge for the first time, functional characterization of LITRs in an autologous system. In addition, the identification of an LITR subset as a cytotoxic cell marker will allow for more effective monitoring of catfish immune responses to pathogens.
authors: Department of Microbiology and Immunology, University of Mississippi Medical Center, Jackson, MS 39216;
authors: Erin B
authors: EB
authors: Taylor
authors: Warmwater Aquaculture Research Unit, U.S. Department of Agriculture-Agricultural Research Service, Stoneville, MS 38776; and.
authors: Mohadetheh
authors: http://orcid.org/0000-0002-9842-4623
authors: M
authors: Moulana
authors: Immunology Research Group, Department of Medical Biology, Faculty of Health Sciences, University of Tromso-Arctic University of Norway, N-9037 Tromso, Norway.
authors: Tor B
authors: http://orcid.org/0000-0002-6933-8419
authors: TB
authors: Stuge
authors: Warmwater Aquaculture Research Unit, U.S. Department of Agriculture-Agricultural Research Service, Stoneville, MS 38776; and.
authors: Sylvie M A
authors: SM
authors: Quiniou
authors: Department of Microbiology and Immunology, University of Mississippi Medical Center, Jackson, MS 39216;
authors: Eva
authors: E
authors: Bengten
authors: Department of Microbiology and Immunology, University of Mississippi Medical Center, Jackson, MS 39216; mwilson@umc.edu.
authors: Melanie
authors: M
authors: Wilson
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000378:metabolism; D049109:Cell Proliferation; D002999:Clone Cells; D003602:Cytotoxicity, Immunologic; D005393:Fish Diseases / Q000276:immunology*; D006566:Herpesviridae Infections / Q000276:immunology*; D007059:Ictaluridae; D052656:Ictalurivirus / Q000276:immunology*; D007114:Immunization; D007962:Leukocytes / Q000276:immunology* / Q000821:virology; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000378:metabolism; D011971:Receptors, Immunologic / Q000276:immunology / Q000378:metabolism*; D015398:Signal Transduction; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology* / Q000821:virology
chemical_list: D000911:Antibodies, Monoclonal; D016692:Receptors, Antigen, T-Cell, gamma-delta; D011971:Receptors, Immunologic