Development of new endotoxin measurement assay using bioluminescence method

Abstract

Turbidimetric kinetic assay is currently used for plasma endotoxin measurement. In our previous study, we reported that its measurement accuracy was not high. Because many endotoxins in the blood exist in the bound state to or are taken up by leukocytes, we developed a measurement method that used leukocyte-rich plasma. This method significantly increased the accuracy of endotoxin measurement. In this study, we investigated whether newly developed automated bioluminescence method can be used to measure endotoxins using LRP. Blood was collected from 24 patients with suspected bacterial infection upon their arrival at our hospital and 8 healthy individuals.　Comparison of measurement times revealed that the automated bioluminescence method required 20 min in all cases. This time was significantly shorter than that for the turbidimetric kinetic assay method. Comparing of the endotoxin levels revealed a significant correlation between the values from both methods. In addition, the automated bioluminescence method tended to show higher values. Considering measurement time and accuracy, the automated bioluminescence method may be an excellent diagnostic tool for infectious diseases.