An anti-plasminogen antibody preparation that inhibits the activation of human plasminogen but enhances the activator activity of the B-chain-streptokinase complex.
An anti-Glu-plasminogen (GLU-PLG) polyclonal antibody antiserum was prepared in the goat, and specific IgG anti-GLU-PLG antibodies were purified by affinity chromatography using a sepharose-GLU-PLG column. In chromogenic assay studies, the anti-GLU-PLG antibody preparation was found to be an effective inhibitor of the activation of PLG, and it produced different inhibition curves with four different PLG activators. 80% inhibition of streptokinase (SK) activation of GLU-PLG occurred with an anti-GLU-PLG antibody/GLU-PLG molar ratio of 1:1, whereas at this ratio only 28% and 36% inhibition of the plasmin-streptokinase (PLN-SK) and the B-chain-streptokinase (B-SK) complexes occurred. At a 1:1 molar ratio of antibody to PLN, no inhibition of PLN activity occurred. When the anti-GLU-PLG antibody preparation was incubated with each PLG activator, an enhancement in the activator activity of the B-SK complex, but not the other activators was observed with mini-plasminogen (MINI-PLG). Enhancement occurred at a molar ratio of 1:1 and reached a peak of 97% enhancement at a molar ratio of 10:1. Enhanced activator activity of the B-SK complex of 49% occurred at a molar ratio of 1:1 when GLU-PLG was the substrate. At higher molar ratios inhibition of activator activity on GLU-PLG was observed, but not on MINI-PLG. These results indicate that there are multiple activator binding sites on PLG, that these four activators all bind differently to GLU-PLG and MINI-PLG, that some antibody populations that are specific for the PLN B-chain can stimulate activator activity, while other antibody populations that are specific for either the PLN A-chain or the B-chain are inhibitory.
Summaria
L
L
Department of Surgery, Evanston Hospital, IL 60201.
Pavlovic
B
B
Sandesara
J
J
D000818:Animals; D000906:Antibodies / Q000302:isolation & purification*; D002851:Chromatography, High Pressure Liquid; D004058:Diffusion; D004338:Drug Combinations / Q000276:immunology; D004591:Electrophoresis, Polyacrylamide Gel; D004789:Enzyme Activation; D005343:Fibrinolytic Agents / Q000276:immunology*; D006041:Goats; D006801:Humans; D010958:Plasminogen / Q000276:immunology*; D013300:Streptokinase / Q000276:immunology*
D000906:Antibodies; D004338:Drug Combinations; D005343:Fibrinolytic Agents; C049423:streptokinase-plasminogen complex; D010958:Plasminogen; D013300:Streptokinase