Bacterial endotoxin interacts with the human immune system via complex immunological pathways. The evaluation of endotoxicity is important in the development of safe vaccines and immunomodulatory therapeutics. The Limulus amebocyte lysate (LAL) assay is generally accepted by the FDA for use for the quantification of lipopolysaccharide (LPS), while the rabbit pyrogen test (RPT) is used to estima...

The Limulus amoebocyte lysate (LAL) test was evaluated for rapid detection of gram-negative bacteriuria in an adult patient population. Time to gelation of a standard LAL preparation was used as a measure of significant (greater than 10(5) bacteria per ml) gram-negative bacteriuria, and the results of 190 LAL assays were compared with quantitative urine cultures. Initially, 33 of 36 urine speci...

The presence of endotoxin (detected by the Limulus amebocyte lysate assay) was compared to the presence of viable Haemophilus influenzae and Moraxella catarrhalis (detected by PCR) in 106 middle-ear effusions from pediatric patients with chronic otitis media. Endotoxin was found in 81 of the 106 specimens. Of these 81 specimens, 66 (81.5%) also tested positive for one or both of the gram-negati...

Spectral sensitivity curves can be distorted by screening pigments. We have determined whether this is true for Limulus polyphemus by determining, from receptor potentials recorded using intracellular microelectrodes, spectral sensitivity curves for normal animals and for white-eyed animals (which lack screening pigment). Our results show: (a) In median ocelli, the curve for UV-sensitive recept...

We present a flexible analytical method for the study of coagulation systems by monitoring elastography (EG). The rapid detection of endotoxin is achieved by the EG analysis of endotoxin-induced limulus amebocyte lysate coagulation. This method is superior to other methods using the same reagents in not only sensitivity but also detecting time.

Applicability of the endotoxin test to diphtheria-tetanus-acellular pertussis combined (DTaP) vaccines was examined. We found some DTaP vaccines that strongly interfered with Limulus amoebocyte lysate (LAL) activity of endotoxin without affecting lethal activity of endotoxin in D-galactosamine-treated mice. LAL activity that was interfered in such vaccines increased apparently after the treatme...

Microorganisms such as Gram-negative or Gram-positive bacteria, viruses and fungi contain components that activate the innate immune system. These components, called pyrogens (Greek: pyros=fire), can occur independently of viable microorganisms and are a major safety concern in parenterally administered drugs, since they can cause severe reactions such as fever, organ failure, and shock in the ...

PURPOSE To measure the endotoxin concentration (EC) of 25 commercially available, hyaluronic acid- and hydroxypropylmethylcellulose-based (HPMC) ophthalmic viscosurgical devices (OVDs). METHODS The in vitro Limulus amebocyte lysate (LAL) assay, which indicates the presence of endotoxins originating from gram-negative bacteria, was used to determine the EC. The procedure was performed accordin...

Elevated plasma lipopolysaccharide (LPS), an indicator of microbial translocation from the gut, is a likely cause of systemic immune activation in chronic HIV infection. LPS induces monocyte activation and trafficking into brain, which are key mechanisms in the pathogenesis of HIV-associated dementia (HAD). To determine whether high LPS levels are associated with increased monocyte activation a...