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Objectives: To study the willingness of dental patients to donate biospecimens for research purpose and to examine factors that may influence such a decision., Materials and Methods: A face-to-face interview was conducted using a pretested structured survey instrument on 408 adult dental patients attending a university hospital for dental care. Descriptive statistics were generated, and the x03C7;2 test was used to examine differences between groups. p values ≤0.5 were considered statistically significant., Results: Of the 408 participants, only 71 (17.4%) had heard of the terms biobanking/biospecimens, but 293 (71.9%) approved of the idea of using biospecimens for biomedical research, and 228 (55.9%) were willing to donate biospecimens and give personal information for research purposes. In participants who were unwilling to participate in biobanking, fear of information leakage was the most frequently reported reason, while in participants who were willing to donate biospecimens, the potential to provide more effective and less costly treatments was the most frequently reported reason. The preferences of the 228 participants who were willing to donate biospecimens were as follows: give a sample of removed oral tissues including extracted teeth (n = 105, 46.1%), donate a blood sample (n = 52, 23%), donate a sample of saliva (n = 43, 18.6%), and give a urine sample (n = 28, 12.3%)., Conclusion: Dental patients had a generally positive attitude towards biomedical research and biobanking. The most preferred types of biospecimens to donate in a dental setting were removed tissues, including extracted teeth and blood samples., (© 2016 S. Karger AG, Basel.)

There is an increasing need in biology and clinical medicine to robustly and reliably measure tens to hundreds of peptides and proteins in clinical and biological samples with high sensitivity, specificity, reproducibility, and repeatability. Previously, we demonstrated that LC-MRM-MS with isotope dilution has suitable performance for quantitative measurements of small numbers of relatively abundant proteins in human plasma and that the resulting assays can be transferred across laboratories while maintaining high reproducibility and quantitative precision. Here, we significantly extend that earlier work, demonstrating that 11 laboratories using 14 LC-MS systems can develop, determine analytical figures of merit, and apply highly multiplexed MRM-MS assays targeting 125 peptides derived from 27 cancer-relevant proteins and seven control proteins to precisely and reproducibly measure the analytes in human plasma. To ensure consistent generation of high quality data, we incorporated a system suitability protocol (SSP) into our experimental design. The SSP enabled real-time monitoring of LC-MRM-MS performance during assay development and implementation, facilitating early detection and correction of chromatographic and instrumental problems. Low to subnanogram/ml sensitivity for proteins in plasma was achieved by one-step immunoaffinity depletion of 14 abundant plasma proteins prior to analysis. Median intra- and interlaboratory reproducibility was <20%, sufficient for most biological studies and candidate protein biomarker verification. Digestion recovery of peptides was assessed and quantitative accuracy improved using heavy-isotope-labeled versions of the proteins as internal standards. Using the highly multiplexed assay, participating laboratories were able to precisely and reproducibly determine the levels of a series of analytes in blinded samples used to simulate an interlaboratory clinical study of patient samples. Our study further establishes that LC-MRM-MS using stable isotope dilution, with appropriate attention to analytical validation and appropriate quality control measures, enables sensitive, specific, reproducible, and quantitative measurements of proteins and peptides in complex biological matrices such as plasma., (© 2015 by The American Society for Biochemistry and Molecular Biology, Inc.)

During T cell activation by antigen-presenting cells (APCs), the diverse spatiotemporal organization of components of T cell signaling pathways modulates the efficiency of activation. Here, we found that loss of the tyrosine kinase interleukin-2 (IL-2)-inducible T cell kinase (Itk) in mice altered the spatiotemporal distributions of 14 of 16 sensors of T cell signaling molecules in the region of the interface between the T cell and the APC, which reduced the segregation of signaling intermediates into distinct spatiotemporal patterns. Activation of the Rho family guanosine triphosphatase Cdc42 at the center of the cell-cell interface was impaired, although the total cellular amount of active Cdc42 remained intact. The defect in Cdc42 localization resulted in impaired actin accumulation at the T cell-APC interface in Itk-deficient T cells. Reconstitution of cells with active Cdc42 that was specifically directed to the center of the interface restored actin accumulation in Itk-deficient T cells. Itk also controlled the central localization of the guanine nucleotide exchange factor SLAT [Switch-associated protein 70 (SWAP-70)-like adaptor of T cells], which may contribute to the activation of Cdc42 at the center of the interface. Together, these data illustrate how control of the spatiotemporal organization of T cell signaling controls critical aspects of T cell function.