An assessment of an automated assay and an ELISA method for collagen binding activity levels using congenital and acquired von Willebrand disease samples

Introduction: Enzyme-linked immunosorbent assay (ELISA) is a platebased assay intended for measuring proteins and antibodies. (1) The ELISA method is tedious and a lengthy process. (2) HemosIL AcuStar VWF:CB is a fully automated method. Several publications have described a comparison between an ELISA method and an automated method. A comparison was performed to evaluate the automated method. Method: A comparison between TECHNOZYM ® vWF:CBA ELISA and HemosIL AcuStar VWF:CB was performed. A total of 44 samples was included in the comparison which included congenital and acquired vWD. A reference interval was established; 50 healthy donors were collected from New Zealand Blood Service and from the laboratory and run on the and HemosIL AcuStar VWF:CB. Results: The HemosIL AcuStar is statistically analysed by Pearson's Correlation coefficient (r2 ) and it showed a strong linear relationship (r=0.9795) with a negative bias of -14.6. The pvalue was 0.0722 (>0.05) which is not statistically significant showing a strong evidence that even with a small sample size, the Hemosil AcuStar is a suitable replacement for Technozyme ELISA method. Conclusions: The statistical analysis demonstrated a good correlation between Acustar VWF:CB and ELISA assays for normal and VWD patients. HemosIL AcuStar VWF:CB is a potential alternative to a ELISA method for measuring CBA levels.