Modular Nucleic Acid Assembled p/MHC Microarrays for Multiplexed Sorting of Antigen-Specific T Cells

The human immune system consists of a large number of T cells capable of recognizing and responding to antigens derived from various sources. The development of peptide-major histocompatibility (p/MHC) tetrameric complexes has enabled the direct detection of these antigen-specific T cells. With the goal of increasing throughput and multiplexing of T cell detection, protein microarrays spotted with defined p/MHC complexes have been reported, but studies have been limited due to the inherent instability and reproducibility of arrays produced via conventional spotted methods. Herein, we report on a platform for the detection of antigen-specific T cells on glass substrates that offers significant advantages over existing surface-bound schemes. In this approach, called “Nucleic Acid Cell Sorting (NACS)”, single-stranded DNA oligomers conjugated site-specifically to p/MHC tetramers are employed to immobilize p/MHC tetramers via hybridization to a complementary-printed substrate. Fully assembled p/MHC arrays are used to detect and enumerate T cells captured from cellular suspensions, including primary human T cells collected from cancer patients. NACS arrays outperform conventional spotted arrays assessed in key criteria such as repeatability and homogeneity. The versatility of employing DNA sequences for cell sorting is exploited to enable the programmed, selective release of target populations of immobilized T cells with restriction endonucleases for downstream analysis. Because of the performance, facile and modular assembly of p/MHC tetramer arrays, NACS holds promise as a versatile platform for multiplexed T cell detection

Demographic and Clinical Variation in Veterans Health Administration Provision of Assistive Technology Devices to Veterans Poststroke

Objectives: To examine variation in provision of assistive technology (AT) devices and the extent to which such variation may be explained by patient characteristics or Veterans Health Administration (VHA) administrative region. Design: Retrospective population-based study. Setting: VHA. Participants: Veterans poststroke in fiscal years 2001 and 2002 (N=12,046). Interventions: Not applicable. Main Outcome Measure: Provision of 8 categories of AT devices. Results: There was considerable regional variation in provision of AT. For example, differences across administrative regions in the VHA ranged from 5.1 to 28.1 standard manual wheelchairs per 100 veterans poststroke. Using logistic regression, with only demographic variables as predictors of standard manual wheelchair provision, the c statistic was .62, and the pseudo R2 was 2.5%. Adding disease severity increased the c statistic to .67 and the pseudo R2 to 6.2%, and adding Veteran Integrated Network System further increased the c statistic to .72 and pseudo R2 to 9.8%. Conclusions: Our research showed significant variation in the provision of AT devices to veterans poststroke, and it showed that patient characteristics accounted for only 6.2% of the variation. VHA administrative region and disability severity accounted for equivalent amounts of the variation

{\eta} and {\eta}' mesons from Nf=2+1+1 twisted mass lattice QCD

We determine mass and mixing angles of eta and eta' states using Nf=2+1+1 Wilson twisted mass lattice QCD. We describe how those flavour singlet states need to be treated in this lattice formulation. Results are presented for three values of the lattice spacing, a=0.061 fm, a=0.078 fm and a=0.086 fm, with light quark masses corresponding to values of the charged pion mass in a range of 230 to 500 MeV and fixed bare strange and charm quark mass values. We obtain 557(15)(45) MeV for the eta mass (first error statistical, second systematic) and 44(5) degrees for the mixing angle in the quark flavour basis, corresponding to -10(5) degrees in the octet-singlet basis.Comment: 28 pages, 9 figures, version to appear in JHEP, extended discussion of autocorrelation times and comparison to results available in the literature, added a comment for FS-effects and clarified the description of our blocking procedur

Renormalisation constants of quark bilinears in lattice QCD with four dynamical Wilson quarks

We present preliminary results of the non-perturbative computation of the RI-MOM renormalisation constants in a mass-independent scheme for the action with Iwasaki glue and four dynamical Wilson quarks employed by ETMC. Our project requires dedicated gauge ensembles with four degenerate sea quark flavours at three lattice spacings and at several values of the standard and twisted quark mass parameters. The RI-MOM renormalisation constants are obtained from appropriate O(a) improved estimators extrapolated to the chiral limit.Comment: 7 pages, 8 figures, Talk presented at the XXIX International Symposium on Lattice Field Theory (Lattice 2011), July 10-16, 2011, Squaw Valley, Lake Tahoe, California, US

A Systematic Review of Music Therapy Practice and Outcomes with Acute Adult Psychiatric In-Patients

PMCID: PMC3732280This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

Simultaneous Detection of Circulating Autoreactive CD8+ T-Cells Specific for Different Islet Cell–Associated Epitopes Using Combinatorial MHC Multimers

textabstractOBJECTIVE - Type 1 diabetes results from selective T-cell-mediated destruction of the insulin-producing β-cells in the pancreas. In this process, islet epitope-specific CD8+T-cells play a pivotal role. Thus, monitoring of multiple islet-specific CD8+T-cells may prove to be valuable for measuring disease activity, progression, and intervention. Yet, conventional detection techniques (ELISPOT and HLA tetramers) require many cells and are relatively insensitive. RESEARCH DESIGN AND METHODS - Here, we used a combinatorial quantum dot major histocompatibility complex multimer technique to simultaneously monitor the presence of HLA-A2 restricted insulin B10-18, prepro-insulin (PPI)15-24, islet antigen (IA)-2797-805, GAD65114-123, islet-specific glucose-6-phosphatase catalytic subunit-related protein (IGRP)265-273, and pre-pro islet amyloid polypeptide (ppIAPP)5-13-specific CD8+T-cells in recent-onset diabetic patients, their siblings, healthy control subjects, and islet cell transplantation recipients. RESULTS - Using this kit, islet autoreactive CD8+T-cells recognizing insulin B10-18, IA-2797-805, and IGRP265-273were shown to be frequently detectable in recent-onset diabetic patients but rarely in healthy control subjects; PPI15-24proved to be the most sensitive epitope. Applying the "Diab-Q-kit" to samples of islet cell transplantation recipients allowed detection of changes of autoreactive T-cell frequencies against multiple islet cell-derived epitopes that were associated with disease activity and correlated with clinical outcome. CONCLUSIONS - A kit was developed that allows simultaneous detection of CD8+T-cells reactive to multiple HLA-A2-restricted β-cell epitopes requiring limited amounts of blood, without a need for in vitro culture, that is applicable on stored blood samples

MHC-based detection of antigen-specific CD8+ T cell responses

The hallmark of adaptive immunity is its ability to recognise a wide range of antigens and technologies that capture this diversity are therefore of substantial interest. New methods have recently been developed that allow the parallel analysis of T cell reactivity against vast numbers of different epitopes in limited biological material. These technologies are based on the joint binding of differentially labelled MHC multimers on the T cell surface, thereby providing each antigen-specific T cell population with a unique multicolour code. This strategy of ‘combinatorial encoding’ enables detection of many (at least 25) different T cell populations per sample and should be of broad value for both T cell epitope identification and immunomonitoring