Characterization of a platelet derived factor modulating phagocyte functions and cooperating with interleukin 1.
During experiments aiming at the generation of monoclonal antibodies against native human interleukin 2 an antibody of different specificity was obtained, recognizing a polypeptide contaminant within the antigen preparation used for immunization. This antigen was shown to represent a release protein from human blood platelets. Amino acid sequence analysis of the immunopurified antigen revealed its identity as beta-thromboglobulin antigen. Depending on the source of antigen (freshly lysed platelets, platelet containing cell culture supernatants) various forms of the polypeptide, differing in the degree of N-terminal truncation, were found. Beta-thromboglobulin antigen preparations differing in peptide composition also had different capacities for modulating spontaneous as well as Fc-receptor dependent chemiluminescence of human monocytes and granulocytes. In contrast to former reports, no mitogenic activity for human dermal fibroblasts was found with beta-TG antigen (CTAP III) alone, but only in combination with human interleukin 1 and heparin, the three molecules acting synergistically. These findings indicate that beta-TG antigen could play a functional role in linking the blood clotting system to the immune system.
Brandt
E
E
Forshungsinstitut Borstel, Institut für Experimentelle Biologie und Medizin, FRG.
Ernst
M
M
Loppnow
H
H
Flad
H D
HD
D000911:Antibodies, Monoclonal; D000941:Antigens / Q000302:isolation & purification; D001792:Blood Platelets / Q000276:immunology*; D002455:Cell Division / Q000187:drug effects; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects / Q000276:immunology; D006493:Heparin / Q000494:pharmacology; D006801:Humans; D066298:In Vitro Techniques; D007375:Interleukin-1 / Q000494:pharmacology / Q000502:physiology*; D008163:Luminescent Measurements; D010586:Phagocytes / Q000276:immunology*; D001620:beta-Thromboglobulin / Q000276:immunology
D000911:Antibodies, Monoclonal; D000941:Antigens; D007375:Interleukin-1; D001620:beta-Thromboglobulin; D006493:Heparin