An excerpt of this article as follows:
Pyrogens are substances that can induce shock, fever or death with the most common type of pyrogen being the gram-negative bacteria-derived lipopolysaccharide or endotoxin.
There are currently three approved methods for the testing of pyrogenicity; the rabbit pyrogen test (RPT), the bacterial endotoxin test (BET) using limulus amoebocyte lysate (LAL) and the monocyte activation test (MAT). Both the BET and the MAT were developed to replace the rabbit pyrogen test in effort to reduce the number of animals used in pyrogen testing.
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