Pyrogen detection methods: Comparison of bovine whole blood assay (bWBA) and monocyte activation test (MAT)

BACKGROUND: Pyrogen detection is of utmost importance in pharmaceutical industry, laboratories and health care institutions. As an alternative to the animal-consuming rabbit pyrogen test or Limulus amoebocyte lysate test, the monocyte activation test was introduced as a gold standard method in the European Pharmacopoeia. However, the monocyte activation test has not gained wide acceptance in practice. METHODS: We stimulated bovine whole blood with different endotoxin preparations (lipopolysaccharide E.coli 0127:B8 and 0113:H10), as well as the non-endotoxin pyrogens peptidoglycan and lipoteichoic acid. Prostaglandin E(2) (PGE(2)) served as read out. RESULTS: Employing PGE(2) as read out enabled detection limits of 0.04 EU/ml for lipopolysaccharide 0127:B8, 0.25 EU/ml for lipopolysaccharide 0113:H10 and 10 μg/ml of lipoteichoic acid as well as peptidoglycan. To evaluate the bWBA test system as a possible alternative to the MAT we performed a peer-to-peer comparison of the two methods and confirmed similar sensitivities. CONCLUSIONS: In conclusion, the bovine whole blood assay (bWBA) reproducibly enabled sensitive detection of endotoxin and non-endotoxin pyrogens and may thus become a viable alternative for pyrogen testing.