Characterization of BMS-911543, a functionally selective small-molecule inhibitor of JAK2.

We report the characterization of BMS-911543, a potent and selective small-molecule inhibitor of the Janus kinase (JAK) family member, JAK2. Functionally, BMS-911543 displayed potent anti-proliferative and pharmacodynamic (PD) effects in cell lines dependent upon JAK2 signaling, and had little activity in cell types dependent upon other pathways, such as JAK1 and JAK3. BMS-911543 also displayed anti-proliferative responses in colony growth assays using primary progenitor cells isolated from patients with JAK2(V617F)-positive myeloproliferative neoplasms (MPNs). Similar to these in vitro observations, BMS-911543 was also highly active in in vivo models of JAK2 signaling, with sustained pathway suppression being observed after a single oral dose. At low dose levels active in JAK2-dependent PD models, no effects were observed in an in vivo model of immunosuppression monitoring antigen-induced IgG and IgM production. Expression profiling of JAK2(V617F)-expressing cells treated with diverse JAK2 inhibitors revealed a shared set of transcriptional changes underlying pharmacological effects of JAK2 inhibition, including many STAT1-regulated genes and STAT1 itself. Collectively, our results highlight BMS-911543 as a functionally selective JAK2 inhibitor and support the therapeutic rationale for its further characterization in patients with MPN or in other disorders characterized by constitutively active JAK2 signaling.

A simple HPLC method for the simultaneous analysis of insulin and ovomucoid.

An analytical HPLC method is reported for the simultaneous determination of insulin and its enzyme inhibitor, chicken ovomucoid. Verapamil was used as an internal standard. The elution was achieved using a gradient technique (10-15% B for 4 min, 15-35% B from 5th to 11th min and 35-10% B from 12th to 22nd min). The mobile phase used was 0.05% v/v trifluoroacetic acid (TFA) in water and 0.05% v/v TFA in acetonitrile with a flow rate of 1.2 ml/min. The analytes were detected at 210 nm after resolution using a reversed phase C-18 column. Insulin, ovomucoid and verapamil (IS) were eluted at 11.9, 14.2, and 18 min, respectively, free from any interfering endogenous peaks during a run time of 22 min. Linear relationships were observed between the detector response and the concentrations of the analytes (0.05-1 I.U/ml for insulin (r2 = 0.9975) and 5-100 microg/ml for the chicken ovomucoid (r2 = 0.9993)). The assay was found to be highly selective and sensitive due to the absence of any interfering peaks. The lower C.V and % error values of the assay indicates that the assay could accurately and precisely quantitate both insulin and ovomucoid in the examined concentration range. This method can be used for the simultaneous quantitation of insulin and chicken ovomucoid.