搜索结果: 'methocult media formulations for mouse hematopoietic cells serum containing'

Carbonic anhydrases (CAs) comprise a family of zinc-containing enzymes that catalyze the reversible hydration of carbon dioxide. CAs contribute to a myriad of physiological processes,including pH regulation,anion transport and water balance. To date,16 known members of the mammalian alpha-CA family have been identified. Given that the catalytic family members share identical reaction chemistry,their physiologic roles are influenced greatly by their tissue and sub-cellular locations. CAVI is the lone secreted CA and exists in both saliva and the gastrointestinal mucosa. An alternative,stress-inducible isoform of CAVI (CAVI-b) has been shown to be expressed from a cryptic promoter that is activated by the CCAAT/Enhancer-Binding Protein Homologous Protein (CHOP). The CAVI-b isoform is not secreted and is currently of unknown physiological function. Here we use neuronal models,including a model derived using Car6 and CHOP gene ablations,to delineate a role for CAVI-b in ischemic protection. Our results demonstrate that CAVI-b expression,which is increased through CHOP-signaling in response to unfolded protein stress,is also increased by oxygen-glucose deprivation (OGD). While enforced expression of CAVI-b is not sufficient to protect against ischemia,CHOP regulation of CAVI-b is necessary for adaptive changes mediated by BDNF that reduce subsequent ischemic damage. These results suggest that CAVI-b comprises a necessary component of a larger adaptive signaling pathway downstream of CHOP. View Publication

The classical model of hematopoiesis predicts a dichotomous lineage restriction of multipotent hematopoietic progenitors (MPPs) into common lymphoid progenitors (CLPs) and common myeloid progenitors (CMPs). However,this idea has been challenged by the identification of lymphoid progenitors retaining partial myeloid potential (e.g.,LMPPs),implying that granulocytes can arise within both the classical lymphoid and the myeloid branches. Here,we resolve this issue by using cell-surface CD133 expression to discriminate functional progenitor populations. We show that eosinophilic and basophilic granulocytes as well as erythrocytes and megakaryocytes derive from a common erythro-myeloid progenitor (EMP),whereas neutrophilic granulocytes arise independently within a lympho-myeloid branch with long-term progenitor function. These findings challenge the concept of a CMP and restore dichotomy to the classical hematopoietic model. View Publication

During drug development,measurement of suitable pharmacodynamic biomarkers is key to establishing in vivo drug activity. Binding of monoclonal antibody (mAb) therapeutics to soluble target proteins often results in elevated serum levels of their target antigen,and measuring total (free and bound) concentration of the target antigen can be an important means of demonstrating that the mAb has reached its specific target. However,accurately measuring soluble circulating antigen in preclinical or clinical samples in the presence of a therapeutic mAb presents a bioanalytical challenge. Particularly in the case of low molecular weight and/or multimeric targets,epitopes for capture and detection of the target by reagent antibodies can be obscured by bound therapeutic mAb. Lymphotoxin-alpha (LTα) is a cytokine in the TNF superfamily that has been implicated in the pathophysiology of autoimmune disease,and is a therapeutic target for neutralizing mAb. During preclinical safety studies in cynomolgus macaques,we encountered difficulties in measuring total LTα in serum of dosed animals. When serum LTα trimer was saturated with the anti-LTα mAb,binding of two reagent antibodies,as required for a classic sandwich ELISA,was not feasible,and dissociation methods were also found to be unsuitable. We therefore developed an approach in which excess anti-LTα mAb was added to the in vitro assay system to fully saturate all binding sites,and an anti-idiotypic antibody was used to detect bound therapeutic antibody. Using this method,total LTα could be accurately measured in cynomolgus macaque serum,and was observed to increase with increasing anti-LTα therapeutic mAb dose. Additional in vitro studies demonstrated that the method worked equally well in human serum. This assay strategy will be useful for quantifying total concentrations of other small and/or multimeric target proteins in the presence of a therapeutic antibody. View Publication

There is a medical need for an agent with the positive effects of estrogen on bone and the cardiovascular system,but without the negative effects on reproductive tissue. Raloxifene (LY139481 HCI) is a benzothiophene derivative that binds to the estrogen receptor and inhibits the effects of estrogen on the uterus. In an ovariectomized (OVX) rat model we investigated the effects of raloxifene on bone loss (induced by estrogen deficiency),serum lipids,and uterine tissue. After oral administration of raloxifene for 5 wk (0.1-10 mg/kg per d) to OVX rats,bone mineral density in the distal femur and proximal tibia was significantly greater than that observed in OVX controls (ED50 of 0.03-0.3 mg/kg). Serum cholesterol was lower in the raloxifene-treated animals,which had a minimal effective dose of 0.1 mg/kg and an approximate oral ED50 of 0.2 mg/kg. The effects of raloxifene on bone and serum cholesterol were comparable to those of a 0.1-mg/kg per d oral dose of ethynyl estradiol. Raloxifene diverged dramatically from estrogen in its lack of significant estrogenic effects on uterine tissue. Ethynyl estradiol produced a marked elevation in a number of uterine histologic parameters (e.g.,epithelial cell height,stromal eosinophilia). These data suggest that raloxifene has promise as an agent with beneficial bone and cardiovascular effects in the absence of significant uterine effects. View Publication