Influence of CD148 polymorphisms on platelet aggregation induced by HIT antibodies. (A-B) Representative platelet aggregation curves obtained with washed platelets from noncarriers (A) and carriers of the CD148 276P/326Q alleles (B) incubated with HIT plasma in the presence of unfractionated heparin (0.5 IU/mL). All donors tested were FcγRIIA 131H/R heterozygotes. (C-D) Lag time (C) and maximum aggregation (D) obtained with 3 different HIT plasma samples in relation to Q276P/R326Q polymorphisms (▩ noncarriers n = 10 and ▨ carriers of 276P/326Q alleles n = 7). All donors tested were FcγRIIA 131H/R heterozygotes. The horizontal lines in the middle of box-and-whiskers plots show the median values. The tops and bottoms of boxes show the 25th and 75th percentiles. The whiskers define the 10th and 90th percentiles. Mann-Whitney U test was performed to compare aggregation parameters in relation to polymorphisms of CD148, and P values are displayed.