| Description | HLA-DRB1 Human Pre-designed siRNA Set A contains three designed siRNAs for HLA-DRB1 gene (Human), as well as a negative control, a positive control, and a FAM-labeled negative control. Components HLA-DRB1 siRNA-1: 5 nmol (HPLC) HLA-DRB1 siRNA-2: 5 nmol (HPLC) HLA-DRB1 siRNA-3: 5 nmol (HPLC) siRNA HLA-DRB1 Human Pre-designed siRNA Set A contains three designed siRNAs for HLA-DRB1 gene (Human), as well as a negative control, a positive control, and a FAM-labeled negative control. Components HLA-DRB1 siRNA-1: 5 nmol (HPLC) HLA-DRB1 siRNA-2: 5 nmol (HPLC) HLA-DRB1 siRNA-3: 5 nmol (HPLC) siRNA Negative Control: 5 nmol (HPLC) FAM-labeled siRNA Negative Control: 5 nmol (HPLC) GAPDH siRNA Positive Control:5 nmol (HPLC)... Read More | Protein Purity>95% by SDS-PAGEExtinction Coeff.A276 nm = 0.456 at 1.0 mg/mLMolecular Weight8,759 Da (single chain)General DescriptionNatural human C4a is prepared by cleavage of human C4 protein by human C1s. It is produced during activation of both the classical and lectin pathways of complementProtein Purity>95% by SDS-PAGEExtinction Coeff.A276 nm = 0.456 at 1.0 mg/mLMolecular Weight8,759 Da (single chain)General DescriptionNatural human C4a is prepared by cleavage of human C4 protein by human C1s. It is produced during activation of both the classical and lectin pathways of complement. C4a is a member of the anaphylatoxin family of three proteins (C3a, C4a and C5a) produced by the activation of complement (Hugli, T.E. et al. (1981)). It is an unglycosylated polypeptidecontaining 77 amino acids with a molecular mass of 8,759 daltons. Many of the biological functions of C4a are similar to those of C3a, but the specific activities are far below those of C3a. C4a activity is so low, in fact, that it was initially thought to be inactive. These measured activities include inducing muscle contraction in the guinea pig ileum test (spasmogenic activity), desensitization of muscle to C3a stimulation suggesting that the same receptor for both C3a and C4a is involved (tachyphylactic activity) and inducing vascular permeability in human skin (Gorski J.P. et al. (1979)). C4a does not show tachyphylactic activity against C5a or chemotactic activity. Removal of the C-terminal arginine by serum carboxypeptidase N destroys all these activities (Meuller-Ortiz, S.L., et al. (2009)). C4a appears to act through the C3a receptor (C3aR) which is a G-protein coupled receptor found widely distributed on peripheral tissues, lymphoid cells (neutrohphils, monocyes, and eosinophils) and in the central nervous system (astrocytes, neurons and glial cells) (Law, S.K.A. and Reid, K.B.M. (1995)). Physical Characteristics & StructureMolecular weight: 8,759 calculated molecular mass. Observed mass (MALDI-TOF) is 8,762 + 9 mass units. pI = 9.0 to 9.5 (Gorski, J.P. et al. (1981))Amino acid sequence (77 amino acids): NVNFQKAINE KLGQYASPTA KRCCQDGVTR LPMMRSCEQR AARVQQPDCR EPFLSCCQFA ESLRKKSRDK GQAGLQRC4a is thought to be structurally very similar to C3a and C5a to which it is homologous. Thus its 3D structure is probably similar to the X-ray-derived crystal structureof C3a (Huber, R. et al. (1980)) and the NMR derived structure of C3a: Nettesheim, D.G. et al. (1988); Murray, I. et al. (1999).FunctionSee General Description above. C4a exhibits much weaker biological activities than C3a and C5a. Its activity in inducing erythema and edema in human skin is 25,000-fold weaker than that of C5a and 100-fold weaker than C3a per nanomole. The spasmogenic activity of C4a is 2000-fold weaker than C5a and 100-fold weaker than that of C3a. Due to these differences the role of C4a in these responses in vivo is thought to be negligible.AssaysTwo well established assays for C4a and C3a functional activities include induction of contraction in the guinea pig ileum and the permeation of a dye such as trypan blue from the vasculature into skin. The anaphylatoxins also induce mast cell degranulation, (measured as histamine release), platelet aggregation, IL-1 release from monocytes and the release of prostaglandins and leukotrienes from many cells and tissues. The other assays used for C3a (Dodds, A.W. and Sim, R.B. (1997)) should also respond to C4a, but few reports have described utilizing these assays with C4a. ELISA kits for the assay of C4a levels (or more correctly C4a desArg levels) in blood and other fluids are sold by several companies. These measurements are useful for detecting complement activation in vivo, but the interpretation of their meaning is complicated by the fact that clearance of the anaphylatoxins is rapid. In vivoFreshly drawn normal human serum contains significant levels of all three anaphylatoxins. Although these may represent the resting concentration in vivo it is difficult to draw or store blood without some complement activation so a true in vivo concentration is difficult to determine. The presence of EDTA and Futhan in the collection tubes can minimize this background (Pfeifer, P.H. et al. (1999)). Full activation of all C4 in blood (600µg/mL) would result in ~3,400 nM C4a (~30 µg/mL). Due to the low biological activity of C4a it could require activation of most of the C4 in a small region to achieve the micromolar C4a concentrations necessary to elicit a response.RegulationC4a levels are regulated by three processes: formation, inactivation and clearance. There are two enzymes that cleave C4 and release C4a: C1s and MASP-2. C4a is “inactivated” by removal of its C-terminal arginine amino acid. The product C4a desArg (or C4a without the C-terminal arginine) is produced by the action of the plasma enzyme carboxypeptidase N (Mueller-Ortiz S.L. et al. (2009)). The inactivation is rapid and most C4a is converted to C4a desArg within minutes of its formation. Inactivated C4a lack measurable biological activity. Because of the large number of cells bearing C3a/C4areceptors (endothelial, immune, smooth muscle, neuronal, etc.) the capture, internalization and digestion of C4a and C4a desArg probably results in its removal from circulation.DeficienciesA deficiency of C4 or a deficiency of all of the enzymes that cleave C4 to generate C4a could result in the absence of C4a. There are no known complete deficiencies of all ofthe C4 cleaving enzymes. Examples of C4 deficient humans and mice exist (Wessels, M.R. et al. (1995)), but the degree to which pathologies associated with C4 deficiency are due to the lack of C4 or the absence of C4a is unclear. DiseasesThere are no known diseases connected to C4a or C4a desArg. Precautions/Toxicity/HazardsThe source of C4a is human serum, therefore appropriate precautions must be observed even though the source was shown by certified tests to be negative for HBsAg, HTLV-I/II, STS, and for antibodies to HCV, HIV-1 and HIV-II.Injection can cause anaphylatic shock which is a generalized circulatory collapse similar to that caused by an allergic reaction.Hazard Code: B WGK Germany 3... Read More | Inquire | Extinction CoeffA280 nm = 1.0 at 1.0 mg/mlGeneral DescriptionProduct is whole polyclonal antiserum from goats immunized with highly purified mouse complement protein. This product is not a purified IgG fraction. Goats are maintained in FDA certified facilities.Physical Characteristics & Extinction CoeffA280 nm = 1.0 at 1.0 mg/mlGeneral DescriptionProduct is whole polyclonal antiserum from goats immunized with highly purified mouse complement protein. This product is not a purified IgG fraction. Goats are maintained in FDA certified facilities.Physical Characteristics & StructureAntibodies present in the antisera are primarily IgG.ApplicationsImmunodiffusion: Effective against NMS and plasma at 1/32 dilution Suggested starting dilutions:Western Blot: 1/500 to 1/1000. Most effective against non-reduced antigen.ELISA: 1/500 to 1/2000... Read More | Vabicaserin hydrochloride is a 5-hydroxytryptamine 2C ( 5-HT 2C ) receptor -selective agonist with an EC 50 of 8 nM.In VitroVabicaserin displaces 125 I-(2,5-dimethoxy)phenylisopropylamine binding from human 5-HT 2C receptor sites in Chinese hamster ovary cell membranes with a K i value of 3 nM and Vabicaserin hydrochloride is a 5-hydroxytryptamine 2C ( 5-HT 2C ) receptor -selective agonist with an EC 50 of 8 nM.In VitroVabicaserin displaces 125 I-(2,5-dimethoxy)phenylisopropylamine binding from human 5-HT 2C receptor sites in Chinese hamster ovary cell membranes with a K i value of 3 nM and is >50-fold selective over a number of serotonergic, noradrenergic, and dopaminergic receptors. Binding affinity determined for the human 5-HT 2B receptor subtype using [ 3 H]5HT is 14 nM. Vabicaserin is a potent and full agonist (EC 50, 8 nM; E max, 100%) in stimulating 5-HT 2C receptor-coupled calcium mobilization and exhibits 5-HT 2A receptor antagonism and 5-HT 2B antagonist or partial agonist activity in transfected cells, depending on the level of receptor expression. Vabicaserin exhibits lower affinity at the 5-HT 2C antagonist binding site (22 nM) labeled with [ 3 H]mesulergine. Additional binding studies indicate that Vabicaserin possesses affinity for the 5-HT 2B and 5-HT 1A receptors with K i values of 14 and 112 nM, respectively. MCE has not independently confirmed the accuracy of these methods. They are for reference only.In VivoAfter a single oral dose of [ 14 C]Vabicaserin at 50, 5, and 15 mg/kg, unchanged drug represents less than 19, 20, and 35% of total plasma radioactivity at all the time points examined in mice, rats, and dogs, respectively. The carbamoyl glucuronide (CG) represents approximately 7 to 36% of plasma radioactivity in mice and 2 to 28% of plasma radioactivity in dogs but is not detected in rat plasma after the single [ 14 C]Vabicaserin dose. However, the CG is observed in rat plasma after multiple-dose administration of Vabicaserin at higher doses, and the CG is approximately 20 times less than Vabicaserin based on steady-state AUC 0-24 values. The estimated plasma AUC 0-24 ratios of CG to the parent drug are 1.5 and 1.7 in mice and dogs after the single [ 14 C]Vabicaserin dose, respectively. The plasma AUC 0-24 ratios for the CG to Vabicaserin at steady state with doses used for safety assessment are less for mice (0.2-0.6) and slightly higher for dogs (1.8-4.0) compared with the single dose values. The CG is detected in dog urine in similar amounts to the parent drug, although it is not detected in mouse or rat urine after the single [ 14 C]Vabicaserin dose. Radioactivity in a 0- to 24-h bile collection from rats receiving a 5 mg/kg [ 14 C]Vabicaserin dose accounts for 19 and 24% of the administered dose in males and females, respectively. Although the CG is not detected in urine or feces of rats after a single oral administration, it represents an average of up to 30% of biliary radioactivity in male rats and 15% in female rats. In monkeys after a single oral 25-mg/kg dose of Vabicaserin, the plasma concentrations of the CG exceeded those of Vabicaserin at all the time points (2-24 h) postdose, although the amount of CG relative to Vabicaserin decreased by 24 h postdose, with ratios of 17.5 at 2 h and 1.7 at 24 h. The CG to Vabicaserin AUC 0-24 ratio of 12:1 indicates that the CG is a major metabolite in monkeys. MCE has not independently confirmed the accuracy of these methods. They are for reference only.Animal administrationMice and Rats For metabolism studies in mice, rats, and dogs, radiolabeled doses are used. Male and female CD-1 mice and Sprague-Dawley rats are used. The dose vehicle for mice and rats contained 2% (w/w) Tween 80 and 0.5% methylcellulose in water. Nonfasted male and female mice weighing from 27.8 to 33.8 g at the time of dosing are given a single 50-mg/kg (∼300 µCi/kg) dose of Vabicaserin at a volume of 20 mL/kg via intragastric gavage. Mice are kept in metabolic cages in groups of five. Nonfasted male rats weighing from 318 to 345 g and female rats weighing from 227 to 255 g at the time of dosing are given a single 5-mg/kg (∼300 µCi/kg) dose of Vabicaserin at a volume of 2.5 mL/kg via intragastric gavage. Four bile duct-cannulated male rats weighing from 387 to 411 g and four bile duct-cannulated female rats weighing from 291 to 325 g at the time of dosing are nonfasted and are given a single 5-mg/kg (323 µCi/kg) dose of Vabicaserin at a volume of 5.0 mL/kg via intragastric gavage. Rats are kept individually in metabolism cages. Dogs Four male beagle dogs, weighing from 7.6 to 9.8 kg at the time of dosing, are from an in-house colony. Approximately 11 mg of [ 14 C]Vabicaserin hydrochloride and 940 mg of nonlabeled Vabicaserin hydrochloride are dissolved in methanol and then evaporated under a nitrogen stream to dryness. Capsules (number 2) are filled with accurate amounts (126.7-138.1 mg) of the mixed drug substance according to animal weights to give a dosage of 15 mg/kg (39 µCi/kg). The filled gelatin capsules are then enteric-coated manually. Each dog is given one enteric-coated capsule containing [ 14 C]Vabicaserin as the hydrochloride salt. Animals are fed 2 h before dosing and are housed individually in metabolic cages. Monkey Four male cynomolgus monkeys, weighing from 5.4 to 9.6 kg at the time of dosing, are from an in-house colony. Nonfasted monkeys are given a single 25-mg/kg dose of nonradiolabeled Vabicaserin at a volume of 2 mL/kg via intragastric gavage. The vehicle is the same as used in mice and rats. Animals are housed individually in metabolic cages. aladdin has not independently confirmed the accuracy of these methods. They are for reference only.IC50& Target:5-HT 2C Receptor 8 nM (EC 50 )... Read More |