Amebocytes

Pyrogenic A fever-producing substance. The presence of these substances is determined by the Limulus Amebocyte Lysate (LAL) test and measured in EU/ml (endotoxin units per milliliter). 

A preferred method for the detection of pyrogens is the limulus amebocyte lysate (LAL) test. A test sample is incubated with amebocyte lysate from the blood of the horseshoe crab, Limulus polyphemus. A pyrogenic substance will cause a gel to form. This is a result of the... 

Develeeshouwer, M.J., Comil, M.F. and Dony, J. (1985). Studies on the sensitivity and specificity of the limulus amebocyte lysate test and rabbit pyrogen assays. Appl. Environ. Microbiol. 50 1509-1511. 

Wearly, M. and Baker, B. (1977). Utilization of the limulus amebocyte lysage test for pyrogen testing of large-volume parenterals, administration sets and medical devices. Bull. Parenter. Drug Assoc. 31 127-133. 

Limulus Amebocyte Eysate (EAE) Test This test is used to detect the presence of endotoxins in the drug substance. It relies on the coagulation reaction between the endotoxin and the blood of a horseshoe crab. 

Limnlus amebocyte lysate A reagent for determining the quantity of bacterial endotoxins. It is obtained from the aqueous extracts of circulating amebocytes of the horseshoe crab. 

Sakai H, Hisamoto S, Fukutomi I, et al. Detection of lipopolysaccharide in hemoglobin-vesicles by Limulus amebocyte lysate test with kinetic-turbidimetric gel clotting analysis and pretreatment of surfactant. J Pharm Sci 2004 93 310. 

Limulus amebocyte lysate is obtained from a licensed manufacturer. Each lot of reagent is tested per USP for release. Endotoxin used in all bacterial endotoxin analysis testing is obtained from a licensed manufacturer and is standardized against the USP reference standard. 

The determination of the endotoxin with limulus amebocyte lysate (LAL) is based on gel formation of a mixture consisting of a solution of endotoxin of Gram-negative bacteria with a solution of lysate. The extent and speed of the reaction depend on the endotoxin concentration, pLL, and temperature. The reaction requires the presence of certain cations, a proclotting enzymes system, and clottable protein, which are produced by lysate. 

Novitsky, TJ. (1996). Limulus amebocyte lysate (LAL) assays. In Automated Microbial Identification and Quantitation Technologies for the 2000s, W.P. Olson, ed. Inter-pharm Press, Buffalo Grove, IL, 277-298. 

Isolated animal cells in tissue culture, no matter how highly differentiated, tend to revert quickly to one of three basic types known as epitheliocytes, mechanocytes, and amebocytes. Epitheliocytes are closely adherent cells derived from epithelial tissues and thought to be related in their origins to the two surface layers of the embryonic blastula. Mechanocytes, often called fibroblasts or fibrocytes, are derived from muscle, supporting, or connective tissue. Like the amebocytes, they arise from embryonic mesenchymal tissue cells that have migrated inward from the lower side of the blastula (Chapter 32). Neurons, neuroglia, and lymphocytes are additional distinct cell types. 

Amebic dystentery 187 Amebocytes 23, 25 Ameloblasts 442 Ameloblastin 442 Amelogenins 442 Amicyanin 817, 883 Amide(s)... 

Limulus Amebocyte Lysate test kit (Pyrogen Plus, BioWhittaker Inc., Walkersville, MD). 

Fie, J.K., Heyneman, D. and Jeong, K.H. (1976) Studies on resistance in snails. 4. Induction of ventricular capsules and changes in the amebocyte-producing organ during sensitization of Biomphalaria glabrata snails. Journal of Parasitology 62, 286-291. 

Following the dry-heat cycle, aseptically transfer the units containing endotoxin to an aseptic area for extraction procedures, sampling, and conducting the limulus amebocyte lysate (LAL) test. 

Endotoxin Detection - from Limulus Amebocyte Lysate to Recombinant Factor C... 

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