Immune-related, lectin-like receptors are differentially expressed in the myeloid and lymphoid lineages of zebrafish

Department of Biology, University of South Florida, 4202 East Fowler Avenue, Tampa, FL 33620, USA.
Immunogenetics (Impact Factor: 2.49). 03/2006; 58(1):31-40. DOI: 10.1007/s00251-005-0064-3
Source: PubMed

ABSTRACT The identification of C-type lectin (Group V) natural killer (NK) cell receptors in bony fish has remained elusive. Analyses of the Fugu rubripes genome database failed to identify Group V C-type lectin domains (Zelensky and Gready, BMC Genomics 5:51, 2004) suggesting that bony fish, in general, may lack such receptors. Numerous Group II C-type lectin receptors, which are structurally similar to Group V (NK) receptors, have been characterized in bony fish. By searching the zebrafish genome database we have identified a multi-gene family of Group II immune-related, lectin-like receptors (illrs) whose members possess inhibiting and/or activating signaling motifs typical of Group V NK receptors. Illr genes are differentially expressed in the myeloid and lymphoid lineages, suggesting that they may play important roles in the immune functions of multiple hematopoietic cell lineages.

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    • "In addition to these considerations, the genomes of two species of bony fish, medaka and zebrafish, have been sufficiently resolved and adequately annotated to make possible the consideration of other gene families in the context of what we understand to be the general features of multigene families encoding the polymorphic NK receptors seen in higher vertebrates. Specifically, no compelling evidence exists for sequence orthologs of either KIRs or class V C-type lectin-related receptors (Zelensky and Gready, 2004; Panagos et al., 2008), members of which constitute MHC I receptors on human and mouse NK cells, respectively. "
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    ABSTRACT: Novel immune-type receptors (NITRs) comprise an exceptionally large, diversified family of activating and inhibitory receptors that has been identified in bony fish. Here, we characterized the structure of an activating NITR that is expressed by a cytotoxic natural killer (NK)-like cell line and that specifically binds an allogeneic B cell target. A single amino acid residue within the NITR immunoglobulin variable (V)-type domain accounts for specificity of the interaction. Structures solved by X-ray crystallography revealed that the V-type domains of NITRs form homodimers resembling rearranging antigen-binding receptor heterodimers. CDR1 elements of both subunits of NITR dimers form ligand-binding surfaces that determine specificity for the nonself target. In the evolution of immune function, it appears that a specific NK type of innate recognition may be mediated by a complex germline multigene family of V structures resembling those that are somatically diversified in adaptive immunological responses.
    Immunity 09/2008; 29(2):228-37. DOI:10.1016/j.immuni.2008.05.018 · 19.75 Impact Factor
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    • "The inability of pre-E11 AGM cells, which have been shown to possess multilineage (including lymphoid) differentiation capacity in vitro (Cumano, 1996), to engraft adult animals may thus be due to immune rejection via natural killer (NK) cells that are highly radioresistant (Waterfall et al., 1987) and efficiently destroy MHCI-deficient cells (Lanier, 2005). Surface molecules related to mammalian NK receptors are expressed in zebrafish leukocytes (Panagos et al., 2006), suggesting that NK cells may play an important role in the immune rejection of transplanted cells. Finally, engraftment may also be difficult due to limited niche space in embryonic recipients. "
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