2018 Volume 67 Issue 3 Pages 334-339
Plasminogen activator inhibitor-1 (PAI-1), an inhibitor of fibrinolysis, is induced by inflammatory cytokines. Therefore, an increase in the concentration of PAI-1 is a significant factor for sepsis-associated disseminated intravascular coagulation. In this study, we evaluated the fundamental performance of the new reagent kit “nanopia PAI-1” for the measurement of PAI-1. The coefficient of variation (CV) of within-run precision was in the range of 1.29–3.85%. In the examination for on-board reagent stability, the concentration of PAI-1 was reduced from day 6 after the first reagent installation, whereas the CV of between-day precision in the case of installing the reagent in each measurement was stable at 2.32–5.09%. No effects of interfering substances on the measurement nor the prozone phenomenon were observed. Satisfactory results were obtained in terms of linearity and quantitation limit. The correlation with the control reagent was strong. In addition, because PAI-1 exists in platelets, we examined the effect of residual platelets on PAI-1 plasma levels. While no difference in PAI-1 was observed among the fresh samples immediately after the preparation of the platelet concentrate, the PAI-1 concentration of the freeze-thawed samples increased with platelet count and the number of freeze-thawing cycles. Therefore, the sample preparation based on the “Expert Consensus on Standardization of Sample Preparation for Clotting Time Assay” and the restriction to one freeze-thawing cycle are necessary for storing the sample for PAI-1 measurement. In conclusion, these results indicate that nanopia PAI-1 has good performance and is valuable for routine and emergency laboratory tests.
