Whole Blood Assay Detects Endotoxin and Non-Endotoxin Pyrogens (P3098)

Pyrogenic contaminations may precipitate adverse effects that range from fever to death. There is limited surveillance on non-endotoxin pyrogens and a sensitive technique to detect them is essential. Cells of the immune system come in contact with pyrogens; this causes the release of mediators that induce fever. The Whole Blood Assay (WBA) exploits this human physiological response; human whole blood is incubated with test samples, and interleukin-1 beta (IL-1β) induced in the presence of pyrogenic contamination is measured by ELISA. In this study, we demonstrate the ability of WBA to detect non-endotoxin pyrogens. Human whole blood was incubated with different doses of the following non-endotoxin pyrogenic stimuli: lipoteichoic acid (gram positive bacteria cell wall), Pam2CSK4, FSL-1 (bacterial diacylated lipoproteins), zymosan (fungal [1, 3] - beta glucan) and fungal spores. Levels of induced IL-1β were compared with endotoxin stimulated blood and unstimulated blood as positive and negative controls respectively. All tested stimuli showed pro-inflammatory response compared to the negative control (p < 0.05) confirming that WBA effectively detects non-endotoxin pyrogens. In conclusion, WBA is a sensitive and valuable assay relevant to the human response to a broad range of pyrogenic stimuli. It can also be easily adapted for application in quality assessment of biotherapeutics and immunotoxicology.