Four members of an Italian family (two with histories of venous thromboembolism) had a qualitative defect of antithrombin III reflected by normal antigen concentrations and half-normal antithrombin activity with or without heparin. Anti-factor Xa activities were consistently borderline low (about 70% of normal). For the propositus' plasma and serum the patterns of antithrombin III in crossed-immunoelectrophoresis with or without heparin were indistinguishable from those of normal plasma or serum. A normal affinity of antithrombin III for heparin was documented by heparin-sepharose chromatography. Affinity adsorption of the propositus' plasma to human α-thrombin immobilized on sepharose beads revealed defective binding of the antithrombin III to thrombin-sepharose. Hence the molecular defect of this variant appears to be at the active site responsible for binding and neutralizing thrombin, thus accounting for the low thrombin inhibitory activity.
|Titolo:||Characterization of an abnormal antithrombin (Milano 2) with defective thrombin binding|
TRIPODI, ARMANDO (Primo)
|Settore Scientifico Disciplinare:||Settore BIO/12 - Biochimica Clinica e Biologia Molecolare Clinica|
Settore MED/09 - Medicina Interna
Settore MED/15 - Malattie del Sangue
|Data di pubblicazione:||1986|
|Appare nelle tipologie:||01 - Articolo su periodico|