List Labs provides endotoxin or lipopolysaccharides (LPS) for research and clinical investigation. This material has been extracted from bacterial cell walls of different strains of E. coli, Salmonella typhimurium and Salmonella minnesota. Several of the endotoxins have been further purified to remove traces of residual protein and nucleic acids, producing either the Ultra Pure or HPTTM. Contact us for more information about E. coli O113, extracted at high purity and under GMP conditions for use in clinical trials: GMP ListTM HPTTM LPS.
LPS structure may be generally described as three linked regions. The first structural feature is the lipid component called Lipid A, primarily responsible for the effects of endotoxin. Linked to Lipid A is the core antigen or R polysaccharide, a short chain of sugars including 2-keto 3-deoxyoctonate (KDO). The third structural feature is attached to the core polysaccharide and is more elaborate, containing up to 40 repeating subunits of 3 to 5 sugars, referred to as the O antigen, O side chain or O polysaccharide. Variations in the composition of the O antigen account for different antibody responses to bacteria species. Lipid A, acting alone or as a component of LPS, is a potent modulator of the mammalian immune response. The presence of Lipid A or LPS in mammalian macrophages or endothelial cells triggers a signaling cascade leading to the secretion of pro-inflammatory cytokines and nitric oxide. LPS also acts as a B cell mitogen.
The origin of businesses is often an interesting story. List Biological Laboratories is no exception. The company was founded in 1978 by Linda Shoer. Linda was an entrepreneurial scientist in Silicon Valley, who’d been relocated with her husband from Boston. She had an idea for a company and leveraged an initial order into a loan […]
By: Md. Elias, Ph.D, Senior Scientist What are Endotoxins? Endotoxins (aka lipopolysaccharide, LPS or lipoglycan) are part of the outer membrane of Gram-negative bacteria consisting of a lipid moiety and a polysaccharide moiety, the latter is composed of an inner core, outer core and O-antigen joined by covalent bonds1. In animals the lipid part of […]
By: Md. Elias, Ph.D, Senior Scientist List Labs is one of the leading manufacturers of high quality adjuvants from bacterial sources. Our highly purified adjuvants for research and development are Tetanus Toxoid (Product #191), Cholera Toxin B Subunit (Product #104), Diphtheria Toxin CRM197 Mutant (Product #149), Adenylate Cyclase Mutant, Cya-AC– (Product #198L), Pertusis Toxin Mutant (Product #184), […]
By: Karen Crawford, Ph.D., President Eva Purro, Director of Quality Assurance Dom C. Ouano, Marketing While most of List Labs’ products are intended as research reagents (Research Grade), several can be produced as GMP products for use in humans. Below are key differences between the two. Research Only VS Preclinical/Clinical/Human Use Reagent grade products for […]
By: Suzanne Canada, Ph.D. Tanager Medical Writing Concerns over outbreaks of potentially serious childhood diseases are in the news again in California with an increase in whooping cough infections in 2014, caused by the pathogen Bordetella pertussis, and a measles outbreak in December 2014 to February 2015. Since outbreaks and epidemics may be infrequent, many […]
By: Karen Crawford, Ph.D. President, List Biological Laboratories, Inc. Many bacterial products are potent immune system activators, helping our bodies identify and defend against microbial invasions. The innate immune system or non-specific immune system is found in animals as well as in plants, fungi and insects and is employed when pathogens break through the […]
By: Suzanne Canada, Ph.D. Tanager Medical Writing Vaccines have been used to help control diseases for more than 200 years and are the common practice for children and adults. Childhood vaccination has substantially reduced the morbidity and mortality from infectious diseases in much of the developed world, and influenza vaccinations have reduced the impact […]
What is Lipopolysaccharide? Lipopolysaccharide (LPS), a component of the outer membrane of Gram-negative bacteria, is a potent stimulator of the vertebrate innate immune system. This innate immune system, mediated by macrophages and dendritic cells, generates a rapid response to infectious agents. Structural patterns common to diverse LPS molecules are recognized by Toll-like receptors (TLR) and […]