Modulation of natural and interleukin-2-induced tumour-cytolytic activities by the members of a protein family related to beta-thromboglobulin.
A preparation of three C-terminal fragments of the platelet protein beta-thromboglobulin was previously described to have immunomodulatory properties on phagocytic cells. One of the components is obviously identical to the recently described neutrophil-activating peptide 2 (NAP-2). In further investigations on this protein preparation (called factor C) we are able to show an additional influence on the tumour-cytolytic activities of mononuclear cells. Total neutralization of the factor C effect, by treating a factor C preparation with specific monoclonal antibody C24 prior to application in cell culture, proved that the effect is really restricted to factor C proteins. If factor C is given in combination with natural interleukin-2 (IL-2) a dose-dependent suppression of IL-2-mediated natural killer lymphokine-activated killer activity can be measured, which is first detectable 72 h after addition of factor C. Suppression does not occur if the both factors are added within a time interval of more than 12 h. Depletion of monocytes from mononuclear cells has no effect on factor-C-mediated cytotoxicity, demonstrating that factor C acts directly on lymphoid cells.
Klein-Struckmeier
A
A
Blood Transfusion Service of Lower Saxony, Department of Research and Development, Springe, Federal Republic of Germany.
Knüver-Hopf
J
J
Mohr
H
H
D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal; D060829:Arthropod Proteins; D002051:Burkitt Lymphoma / Q000276:immunology / Q000473:pathology / Q000628:therapy; D000001:Calcimycin / Q000494:pharmacology; D002478:Cells, Cultured; D003602:Cytotoxicity, Immunologic / Q000187:drug effects* / Q000276:immunology; D004357:Drug Synergism; D004792:Enzyme Precursors / Q000494:pharmacology*; D006801:Humans; D007111:Immunity, Cellular / Q000187:drug effects; D007167:Immunotherapy; D007376:Interleukin-2 / Q000494:pharmacology*; D015979:Killer Cells, Lymphokine-Activated / Q000187:drug effects; D007694:Killer Cells, Natural / Q000187:drug effects; D007963:Leukocytes, Mononuclear / Q000166:cytology / Q000187:drug effects / Q000276:immunology; D008213:Lymphocyte Activation / Q000187:drug effects; D008214:Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000276:immunology; D008969:Molecular Sequence Data; D012697:Serine Endopeptidases / Q000494:pharmacology*; D013268:Stimulation, Chemical; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D013997:Time Factors; D014407:Tumor Cells, Cultured; D001620:beta-Thromboglobulin / Q000494:pharmacology*
D000911:Antibodies, Monoclonal; D060829:Arthropod Proteins; D004792:Enzyme Precursors; D007376:Interleukin-2; D001620:beta-Thromboglobulin; D000001:Calcimycin; D012697:Serine Endopeptidases; C057151:Limulus clotting factor C; D013755:Tetradecanoylphorbol Acetate