System comprises four plasma proteins, circulating as zymogens in the bloodstream or being assembled on various cell types: the serine proteases factor XII (FXII), factor XI (FXI), and prekallikrein (PKK) and the nonenzymatic cofactor high-molecularweight kininogen (HK). The latter forms equimolar complexes with plasma kallikrein (PK) or FXI. The cascade is initiated upon contact to a negatively c
System comprises four plasma proteins, circulating as zymogens in the bloodstream or being assembled on various cell types: the serine proteases factor XII (FXII), factor XI (FXI), and prekallikrein (PKK) and the nonenzymatic cofactor high-molecularweight kininogen (HK). The latter forms equimolar complexes with plasma kallikrein (PK) or FXI. The cascade is initiated upon contact to a negatively c
System comprises four plasma proteins, circulating as zymogens in the bloodstream or being assembled on various cell types: the serine proteases factor XII (FXII), factor XI (FXI), and prekallikrein (PKK) and the nonenzymatic cofactor high-molecularweight kininogen (HK). The latter forms equimolar complexes with plasma kallikrein (PK) or FXI. The cascade is initiated upon contact to a negatively c
Ons trigger an activation of the contact system more potently than strains isolated from noninvasive infections. The present study gives new insights into the mechanisms by which S. pyogenes triggers the human contact system and stresses the function of soluble and surface located plasmin exploited as a group A streptococcal virulence factor through the action of streptokinase. treptococcus pyogen
N activator streptokinase might contribute to contact system activation by S. pyogenes. Here, we report that the human contact system is activated by the action of streptokinase. The role of secreted and surfacebound streptokinase in this process was investigated by comparing an M49 S. pyogenes wild-type strain with its isogenic ska mutant, which is unable to trigger plasmin activity in human plas
E bradykinin. The nonapeptide has a very short half-life (a matter of seconds) and exhibits its functions via the B1 and B2 receptors (3). Generating other mediators such as nitric oxide, prostaglandins, and leukotrienes, bradykinin is involved in the regulation of blood pressure, the induction of fever and pain, vascular leakage, and the chemotaxis of immune cells (4). In addition, further proces
E bradykinin. The nonapeptide has a very short half-life (a matter of seconds) and exhibits its functions via the B1 and B2 receptors (3). Generating other mediators such as nitric oxide, prostaglandins, and leukotrienes, bradykinin is involved in the regulation of blood pressure, the induction of fever and pain, vascular leakage, and the chemotaxis of immune cells (4). In addition, further proces
Ons trigger an activation of the contact system more potently than strains isolated from noninvasive infections. The present study gives new insights into the mechanisms by which S. pyogenes triggers the human contact system and stresses the function of soluble and surface located plasmin exploited as a group A streptococcal virulence factor through the action of streptokinase. treptococcus pyogen