title: Activation of natural killer-like YT-INDY cells by oligodeoxynucleotides and binding by homologous pattern recognition proteins.
abstract: The present study was designed to examine the binding and signalling effects of single base and CpG dinucleotide phosphodiester (Po) oligodeoxynucleotides (ODN) on the human natural killer (NK)-like cell line (YT-INDY). Single base Po ODN composed of 20-mers of guanosine (dG20), adenosine (dA20), cytosine (dC20) or thymidine (dT20) as well as 'conventional' Po CpG ODN were examined for their ability to bind and activate YT-INDY cells. Binding by dG20 and CpG ODN to YT-INDY cells was saturable and specific. dG20 binding was competitively inhibited by homologous dG20 and heterologous CpG ODN but not by dC20 and dA20. Two different YT-INDY membrane proteins (18 and 29 kDa) were identified by ligand (Southwestern) blotting with biotinylated dG20 and CpG. The specificity of the ODN-binding protein(s) was further confirmed by ODN depletion experiments using a teleost recombinant protein orthologue [nonspecific cytotoxic cells (NCC) cationic antimicrobial protein-1 (ncamp-1)] known to bind CpG and dG20. Cell proliferation and activation studies showed that dG20 and CpG treatment of YT-INDY cells induced cellular DNA synthesis (i.e. G1 to S-phase conversion). This signalling function was accompanied in dG20-treated cells by proliferation 10 h posttreatment. Both dG20 and CpG ODN binding induced a calcium flux in YT-INDY cells within seconds of treatment. These experiments demonstrated that Po single base dG20 and CpG ODN bind to a (potential) new class of cell-surface proteins that mediate the activation of YT-INDY cells.
authors.affiliation: Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, 30602, USA.
authors.forename: H
authors.initials: H
authors.lastname: Kaur
authors.forename: L
authors.initials: L
authors.lastname: Jaso-Friedmann
authors.forename: J H
authors.initials: JH
authors.lastname: Leary
authors.forename: K
authors.initials: K
authors.lastname: Praveen
authors.forename: Z
authors.initials: Z
authors.lastname: Brahmi
authors.forename: D L
authors.initials: DL
authors.lastname: Evans
mesh_terms: D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000906:Antibodies; D026501:Blotting, Southwestern; D002118:Calcium / Q000378:metabolism; D045744:Cell Line, Tumor; D018899:CpG Islands / Q000235:genetics / Q000276:immunology*; D004268:DNA-Binding Proteins / Q000378:metabolism; D006657:Histones / Q000276:immunology; D006801:Humans; D007694:Killer Cells, Natural / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D008213:Lymphocyte Activation / Q000187:drug effects / Q000276:immunology*; D009838:Oligodeoxyribonucleotides / Q000276:immunology* / Q000494:pharmacology; D011485:Protein Binding / Q000276:immunology; D051192:Receptors, Pattern Recognition / Q000378:metabolism*
chemical_list: D000276:Adjuvants, Immunologic; D000906:Antibodies; C408982:CPG-oligonucleotide; D004268:DNA-Binding Proteins; D006657:Histones; D009838:Oligodeoxyribonucleotides; D051192:Receptors, Pattern Recognition; D002118:Calcium