Specific types of activated Factor XII increase following thrombolytic therapy with tenecteplase

Abstract

In patients admitted with STEMI, thrombolytic therapy with TNK-tpa resulted in a significant short-lasting increase in specific types of XIIa (namely XIIaA), whereas other types of XIIa (XIIaR) were largely unaffected by this intervention.

Changes of plasma activated Factor XII type A (XIIaA) concentrations following percutaneous coronary intervention (PCI)

“…No data exists as to whether the recently described specific types of XIIa might exert different actions in CAD. We have previously described an immediate increase of one specific type of XIIa (XIIaA) following thrombolytic therapy with tenecteplase [5]. However, our data could not answer sufficiently whether the increases following treatment were caused by tenecteplase alone or whether concomitant treatment may have contributed to the changes in XIIaA.…”

“…XIIa measurements were performed on all samples using two microtitre plate ELISA assays preferentially measuring different types of activated Factor XII [4,5]. Both assays employed a highly specific monoclonal antibody (Mab 2/215) that reacts with XIIa but shows no detectable binding to Factor XII zymogen [8].…”

“…Both assays employed a highly specific monoclonal antibody (Mab 2/215) that reacts with XIIa but shows no detectable binding to Factor XII zymogen [8]. A detailed description of the sample analysis for the determination of XIIaA and XIIaR has been recently reported [5].…”

“…Recent research indicates that in-vivo XIIa exists in multiple forms [4,5], two of which have been termed XIIaA and XIIaR. XIIaR is characterised by the necessity of exposing the epitope by adding an agent (such as Triton) to disrupt binding of the XIIa to other molecular species, whilst XIIaA requires no such treatment before it is measured.…”

“…XIIaR is characterised by the necessity of exposing the epitope by adding an agent (such as Triton) to disrupt binding of the XIIa to other molecular species, whilst XIIaA requires no such treatment before it is measured. We have recently reported that treatment with tenecteplase leads to a short lasting increase in blood concentrations of XIIaA, whereas concentrations of XIIaR remained unchanged [5]. During the last decade, PCI with stent implantation has been shown to be superior to thrombolysis and has become the golden standard therapy for the treatment of STEMI [6].…”