The relationship between ABO groups and subgroups, factor VIII and von Willebrand factor

Area of Science:

• Hematology
• Immunogenetics
• Molecular Biology

Background:

• ABO blood group antigens are expressed on various cells, including platelets and endothelial cells.
• These antigens can influence the levels of certain coagulation factors, such as von Willebrand factor (VWF) and factor VIII (FVIII).
• Understanding these relationships is crucial for assessing hemostasis and thrombosis risk.

Purpose of the Study:

• To investigate the correlation between different ABO blood groups and plasma levels of VWF antigen (VWF:Ag), FVIII, and VWF ristocetin cofactor activity (VWF:RCo).
• To compare factor levels across various ABO subgroups, including rare phenotypes.

Main Methods:

• Blood group phenotyping using serological and molecular tests on 114 donors.
• Quantification of plasma VWF:Ag, FVIII, and VWF:RCo levels.
• Statistical analysis to determine correlations and significant differences between groups.

Main Results:

• Plasma levels of VWF:Ag, FVIII, and VWF:RCo in rare subgroups (A3O1, AxO1, BelO1) were comparable to the O1O1 group.
• A2O1 blood group donors exhibited significantly higher levels of VWF:Ag (p=0.01), FVIII (p=0.04), and VWF:RCo (p<0.001) compared to O1O1 donors.
• Strong positive correlations were found between VWF:Ag and FVIII (R=0.77; p=0.001), and between VWF:Ag and VWF:RCo (R=0.75; p=0.001).

Conclusions:

• The ABO blood group, particularly the A2 subgroup, is associated with variations in VWF and FVIII plasma levels.
• These findings highlight the impact of specific ABO genotypes on hemostatic factor concentrations.
• Further research may elucidate the mechanisms underlying these blood group-dependent differences in coagulation factors.