Epitope mapping of monoclonal antibodies by mass spectrometry: Identification of protein antigens in complex biological systems

We describe the application of immunoaffinity extraction and mass spectrometry to the analysis of Ty1 Gag protein in lysates of Saccharomyces cerevisiae. A magnetic bead-conjugated monoclonal antibody was used to achieve selective extraction, the specificity of which was established by matrix-assisted laser desorption/ionization mass spectrometric (MS) analysis of an extract of the lysate of cells overexpressing the Ty1 Gag protein. MS analysis of similar extracts of lysates following tryptic hydrolysis confirmed selective extraction of the epitope-containing peptide fragment. Sufficient sensitivity was achieved to allow the application of this approach to the analysis of lysates of wild-type cells. Furthermore, the sequence of the epitope-containing peptide was confirmed by electrospray-tandem MS. To our knowledge, this constitutes the first report of the application of immunoaffinity extraction and tandem MS analysis to the characterization of an antigen recovered from a complex cellular system

The 412 retrotransposon and the development of gonadal mesoderm in Drosophila

We have shown that the expression of the 412 retrotransposon provides a useful early marker for the development of the gonadal mesoderm in Drosophila embryos. 412 is initially expressed in a set of parasegmentally repeated stripes from parasegments (PS) 2-14 in the mesoderm at the extended germ band stage. During germ band retraction the bulk of 412 expression declines except in dorsolateral clusters of cells in PS10, 11 and 12, where high levels of 412 expression remain. These mesodermal cell clusters are associated with germ cells and subsequently they coalesce, rounding up to form the gonads. The gonadal mesoderm thus appears to originate specifically from three abdominal parasegments, PS10, 11 and 12. We show that the maintenance of high levels of 412 expression in gonadal mesoderm is not induced by contact with germ cells, but rather depends on genetic control by the homeotic genes abdominal-A and Abdominal-B

The consultant practitioner: an evolving role to meet changing NHS needs.

Since the introduction of the consultant practitioner role, with its huge variability in purpose and context, it has had to evolve in response to the changing needs of the NHS to achieve sustainability and transformation of services. AIM: This article reflects on the relevance of the consultant practitioner role and the impact of an action learning set in hastening its evolution in one NHS foundation trust. METHOD: From a process of collective critical reflection on their practice, six consultant practitioners analysed the impact they have had on influencing services and empowerment of their patients. Additionally, they have analysed the impact of an externally facilitated action learning set as a catalyst for change. RESULTS: All six consultant practitioners recognised that working together through the learning set enabled them to be more influential and effective. It encouraged them to share their experiences of continuous service improvement and crystalised their views on the impact they have had in delivering the organisation's vision. CONCLUSION: From their critical reflection, the six consultant practitioners acknowledged the influence of the action learning set on accelerating their confidence and competence to lead, and evaluating new models of care delivery at scale and pace. They recognised how far they have travelled in achieving the four dimensions of the role and ultimately their impact on their local sustainability and transformation plan (STP) and their trust's vision