Characterization of congenital antithrombin III (AT III) deficiency was determined with 2 dimensional crossed immunoelectrophoresis (CIE). CIE of a family member showed that the fast moving peak composed of AT III-heparin complex became smaller than normal plasma when CIE ran with high molecular heparin fraction.
However, the fast moving peak became bigger when that ran with low molecular heparin fraction. Especially, the family member (propositus' brother) was found to have considerably the large fast moving peak. It was thought as one of the reasons why his AT III showed normal heparin cofactor activity in spite of a half of it's antigen level.
CIE was determined after the infusion of AT III concentrate in propositus. As the increased level of it's antigen, the slow moving peak in CIE became bigger than original CIE. Also, it was suggested that there was abnormal AT III with low affinity to heparin in plasma's AT III after the infusion of concentrate. But the discrepancy between the functional activity and antigen level could not be found in the plasmas after AT III concentrate infusion.
Transient abnormality in CIE after the concentrate was shown to have the same electrophoretic heterogeneity as appearing under Sas' classification of 'classical' congenital AT III heterogeneity.