ELISA

Programmed death-ligand 1 (PD-L1), also known as cluster of differentiation 274 (CD274) or B7 homolog 1 (B7-H1), is a protein that in humans is encoded by the CD274 gene. PD-L1 is a 40kDa type 1 transmembrane protein that has been speculated to play a major role in suppressing the immune system during particular events such as pregnancy, tissue allografts, autoimmune disease and other disease states such as hepatitis. Normally the immune system reacts to foreign antigens where there is some accumulation in the lymph nodes or spleen which triggers a proliferation of antigen-specific CD8+ T cell. The formation of PD-1 receptor / PD-L1 or B7.1 receptor /PD-L1 ligand complex transmits an inhibitory signal which reduces the proliferation of these CD8+ T cells at the lymph nodes and supplementary to that PD-1 is also able to control the accumulation of foreign antigen specific T cells in the lymph nodes through apoptosis which is further mediated by a lower regulation of the gene Bcl-2.

Iduronate 2-sulfatase (IDS) is a sulfatase enzyme associated with Hunter syndrome. It encodes a member of the sulfatase family of proteins. Iduronate 2-sulfatase is involved in the lysosomal degradation of the glycosaminoglycans heparan sulfate and dermatan sulfate. The encoded preproprotein is proteolytically processed to generate two polypeptide chains. Mutations in this gene are associated with the X-linked lysosomal storage disease mucopolysaccharidosis type II, also known as Hunter syndrome. Alternative splicing results in multiple transcript variants, at least one of which encodes a preproprotein that is proteolytically processed.

Iduronate 2-sulfatase (IDS) is a sulfatase enzyme associated with Hunter syndrome. It encodes a member of the sulfatase family of proteins. Iduronate 2-sulfatase is involved in the lysosomal degradation of the glycosaminoglycans heparan sulfate and dermatan sulfate. The encoded preproprotein is proteolytically processed to generate two polypeptide chains. Mutations in this gene are associated with the X-linked lysosomal storage disease mucopolysaccharidosis type II, also known as Hunter syndrome. Alternative splicing results in multiple transcript variants, at least one of which encodes a preproprotein that is proteolytically processed.

Apolipoprotein E (APOE) is a class of apolipoprotein found in the chylomicron and Intermediate-density lipoprotein (IDLs) that is essential for the normal catabolism of triglyceride-rich lipoprotein constituents. In peripheral tissues, APOE is primarily produced by the liver and macrophages, and mediates cholesterol metabolism in an isoform- dependent manner. In the central nervous system, APOE is mainly produced by astrocytes, and transports cholesterol to neurons via APOE receptors, which are members of the low density lipoprotein receptor gene family. This protein is involved in Alzheimer’s disease and cardiovascular disease.

Apolipoprotein A1 is a protein that in humans is encoded by the APOA1 gene. This gene encodes apolipoprotein A-I, which is the major protein component of high density lipoprotein (HDL) in plasma. The encoded preproprotein is proteolytically processed to generate the mature protein, which promotes cholesterol efflux from tissues to the liver for excretion, and is a cofactor for lecithin cholesterol acyltransferase (LCAT), an enzyme responsible for the formation of most plasma cholesteryl esters. This gene is closely linked with two other apolipoprotein genes on chromosome 11. Defects in this gene are associated with HDL deficiencies, including Tangier disease, and with systemic non-neuropathic amyloidosis. Alternative splicing results in multiple transcript variants, at least one of which encodes a preproprotein.

8-hydroxy-2-deoxy Guanosine (8-OHdG) is produced by the oxidative damage of DNA by reactive oxygen and nitrogen species and serves as an established marker of oxidative stress. Hydroxylation of guanosine occurs in response to both normal metabolic processes and a variety of environmental factors (i.e., anything that increases reactive oxygen and nitrogen species). Increased levels of 8-OHdG are associated with the aging process as well as with a number of pathological conditions including cancer, diabetes, and hypertension. In complex samples such as plasma, cell lysates, and tissues, 8-OHdG can exist as either the free nucleoside or incorporated in DNA. Once the blood enters the kidney, free 8-OHdG is readily filtered into the urine, while larger DNA fragments remain in the bloodstream. Because of the complexity of plasma samples, urine is a more suitable matrix for the measurement of free 8-OHdG than plasma. Urinary levels of 8-OHdG range between 2.7-13 ng/mg creatine, while plasma l

Nitrotyrosine has been identified as a marker of inflammation and NO production. Nitrotyrosine is formed in presence of the active metabolite NO. Various pathways including the formation of peroxinitrite lead to nitrotyrosine production. Since nitrotyrosine is a stable end product of peroxynitrite oxidation, assessment of its plasma concentration may be useful as a marker of NO-dependent damage in vivo. Since NOX is only an indicator for enhanced NO production, protein associated nitrotyrosine might be a more suitable marker for damage induced by reactive nitrogen intermediates derived from NO. Furthermore, most proteins have a longer half life in the circulation than NOX levels. The presence of nitrotyrosine has been detected in various inflammatory processes including atherosclerotic plaques, celiac disease, rheumatoid arthritis, chronic renal failure and septic shock. In normal plasma low, undetectable, levels of nitrotyrosine are present. Nitrosylation of the amino acid tyrosine oc

TMB ELISA Peroxidase Substrate (3, 3', 5, 5' - Tetramethylbenzidine) is a chromogenic substrate used to visualize antibody reactivity in ELISA experiments. In the presence of peroxidases, TMB can act as an electron donor for the conversion of peroxides to water, changing the color of solution to a blue color equivalent to the degree of reactivity. This reaction can be halted with acid to change the TMB to yellow. TMB ELISA Peroxidase Substrate is ideal for investigators in Microbiology, Immunology, and Cancer research.

TMB ELISA Peroxidase Substrate (3, 3', 5, 5' - Tetramethylbenzidine) is a chromogenic substrate used to visualize antibody reactivity in ELISA experiments. In the presence of peroxidases, TMB can act as an electron donor for the conversion of peroxides to water, changing the color of solution to a blue color equivalent to the degree of reactivity. This reaction can be halted with acid to change the TMB to yellow. TMB ELISA Peroxidase Substrate is ideal for investigators in Microbiology, Immunology, and Cancer research.