10 research outputs found
COMPETITION AMONG HOSPITALS AND ITS MEASUREMENT: THEORY AND A CASE STUDY
Our paper provides several insights on the characteristics of the concept of “Poles d’Excellence Rurale” (PER) through bilateral comparisons with that of Competitive Pole (CP) and cluster. The concept of PER is a French government’ initiative designed for the development of rural areas similar to that of the Competitive Pole. We emphasize important particularities of these concepts by analyzing some of their similarities and major differences.Pole d’Excellence Rurale, Competitive Pole, cluster, rural development
Rare Copy Number Variants Observed in Hereditary Breast Cancer Cases Disrupt Genes in Estrogen Signaling and TP53 Tumor Suppression Network
Breast cancer is the most common cancer in women in developed countries, and the contribution of genetic susceptibility to breast cancer development has been well-recognized. However, a great proportion of these hereditary predisposing factors still remain unidentified. To examine the contribution of rare copy number variants (CNVs) in breast cancer predisposition, high-resolution genome-wide scans were performed on genomic DNA of 103 BRCA1, BRCA2, and PALB2 mutation negative familial breast cancer cases and 128 geographically matched healthy female controls; for replication an independent cohort of 75 similarly mutation negative young breast cancer patients was used. All observed rare variants were confirmed by independent methods. The studied breast cancer cases showed a consistent increase in the frequency of rare CNVs when compared to controls. Furthermore, the biological networks of the disrupted genes differed between the two groups. In familial cases the observed mutations disrupted genes, which were significantly overrepresented in cellular functions related to maintenance of genomic integrity, including DNA double-strand break repair (P = 0.0211). Biological network analysis in the two independent breast cancer cohorts showed that the disrupted genes were closely related to estrogen signaling and TP53 centered tumor suppressor network. These results suggest that rare CNVs represent an alternative source of genetic variation influencing hereditary risk for breast cancer
Thyrotropin receptor-specific lymphocytes in adenovirus-TSHR-immunized native and human leukocyte antigen-DR3-transgenic mice and in Graves' disease patient blood
BACKGROUND: Antigen-specific lymphocytes are increasingly investigated in autoimmune diseases and immune therapies. We sought to identify thyrotropin receptor (TSHR)-specific lymphocytes in mouse models of Graves' disease, including Graves' patient-specific immunotype human leukocyte antigen (HLA)-DR3, and in frozen and thawed Graves' patient blood samples. METHODS AND RESULTS: Splenic lymphocytes of adenovirus (Ad)-TSHR-immunized BALB/c mice were stimulated with TSHR-specific peptides C, D, or J. Furthermore, CD154-expressing cells were enriched, expanded in vitro, and analyzed for binding of peptide-major histocompatibility complex (MHC) II multimers ("tetramers," immunotype H2-IA(d)). Only peptides C and J were able to elicit increased expression/secretion of CD154 and interferon-Îł, and tetramers which were loaded with peptide C resulted in antigen-specific signals in splenic lymphocytes from Ad-TSHR-immunized mice. Accordingly, TSHR-specific HLA-DR3-MHC class II tetramers loaded with peptide p10 specifically bound to human HLA-DR3-(allele B1*03:01)-transgenic Bl/6 mouse splenic T lymphocytes. In addition, we fine-tuned a protocol to reliably measure thawed human peripheral blood mononuclear cells (PBMCs), which resulted in reliable recovery after freezing and thawing with regard to vitality and B and T cell subpopulation markers including regulatory T cells (CD3, CD4, CD25, FoxP3, CD25(high), CD127(low)). TSHR-specific HLA-DR3-MHC class II tetramers loaded with peptide p10 identified antigen-specific T cells in HLA-DR3-positive Graves' patients' thawed PBMCs. Moreover, stimulation-dependent release of interleukin (IL)-1beta, IL-6, tumor necrosis factor-alpha from thawed PBMCs occurred at the expected levels. CONCLUSIONS: Novel MHC II tetramers identified TSHR-specific T lymphocytes in Ad-TSHR-immunized hyperthyroid BALB/c or HLA-DR3-transgenic mice and in thawed human PBMCs from patients with Graves' disease. These assays may contribute to measure both disease severity and effects of novel immune therapies in future animal studies and clinical investigations of Graves' disease
Targeting Merkel cell carcinoma by engineered T cells specific to T-antigens of Merkel cell polyomavirus
Purpose: The causative agent of most cases of Merkel cell carcinoma (MCC) has been identified as the Merkel cell polyomavirus (MCV). MCV-encoded T-antigens (Tags) are essential not only for virus-mediated tumorigenesis but also for maintaining MCC cell lines in vitro. MCV Tags are thus an appealing target for viral oncoprotein-directed T cell therapy for MCC. With this study, we aimed to isolate and characterize Tag-specific T cell receptors (TCR) for potential use in gene therapy clinical trials. Experimantal design: T cell responses against MCV Tag epitopes were investigated by immunizing transgenic mice that express a diverse human TCR repertoire restricted to HLA-A2. Human lymphocytes genetically engineered to express Tag-specific TCRs were tested for specific reactivity against MCC cell lines. The therapeutic potential of Tag-specific TCR gene therapy was tested in a syngeneic cancer model. Results: We identified naturally processed epitopes of MCV Tags and isolated Tag-specific TCRs. T cells expressing these TCRs were activated by HLA-A2-positive cells loaded with cognate peptide or cells that stably expressed MCV Tags. We showed cytotoxic potential of T cells engineered to express these TCRs in vitro and demonstrated regression of established tumors in a mouse model upon TCR gene therapy. Conclusions: Our findings demonstrate that MCC cells can be targeted by MCV Tag-specific TCRs. Although recent findings suggest that approximately half of MCC patients benefit from PD1 pathway blockade, additional patients may benefit if their endogenous T cell response can be augmented by infusion of transgenic MCV-specific T cells such as those described here
Tumor-infiltrating merkel cell polyomavirus-specific T cells are diverse and associated with improved patient survival
Tumor-infiltrating CD8(+) T cells are associated with improved survival of patients with Merkel cell carcinoma (MCC), an aggressive skin cancer causally linked to Merkel cell polyomavirus (MCPyV). However, CD8(+) T-cell infiltration is robust in only 4% to 18% of MCC tumors. We characterized the T-cell receptor (TCR) repertoire restricted to one prominent epitope of MCPyV (KLLEIAPNC, "KLL") and assessed whether TCR diversity, tumor infiltration, or T-cell avidity correlated with clinical outcome. HLA-A*02:01/KLL tetramer(+) CD8(+) T cells from MCC patient peripheral blood mononuclear cells (PBMC) and tumor-infiltrating lymphocytes (TIL) were isolated via flow cytometry. TCR{beta} (TRB) sequencing was performed on tetramer(+) cells from PBMCs or TILs (n = 14) and matched tumors (n = 12). Functional avidity of T-cell clones was determined by IFN{gamma} production. We identified KLL tetramer(+) T cells in 14% of PBMC and 21% of TIL from MCC patients. TRB repertoires were strikingly diverse (397 unique TRBs were identified from 12 patients) and mostly private (only one TCRb clonotype shared between two patients). An increased fraction of KLL-specific TIL (>1.9%) was associated with significantly increased MCC-specific survival P = 0.0009). T-cell cloning from four patients identified 42 distinct KLL-specific TCRa/b pairs. T-cell clones from patients with improved MCC-specific outcomes were more avid (P < 0.05) and recognized an HLA-appropriate MCC cell line. T cells specific for a single MCPyV epitope display marked TCR diversity within and between patients. Intratumoral infiltration by MCPyV-specific T cells was associated with significantly improved MCC-specific survival, suggesting that augmenting the number or avidity of virus-specific T cells may have therapeutic benefit
Misregulation of mitotic chromosome segregation in a new type of autosomal recessive primary microcephaly
Primary autosomal recessive microcephaly (MCPH) is a congenital disorder characterized by a pronounced reduction of brain size and mental retardation. We present here a consanguineous Turkish family clinically diagnosed with MCPH and without linkage to any of the known loci (MCPH1-MCPH7). Autozygosity mapping identified a homozygous region of 15.8 Mb on chromosome 10q11.23-21.3, most likely representing a new locus for MCPH. Although we were unable to identify the underlying genetic defect after extensive molecular screening, we could delineate a possible molecular function in chromosome segregation by the characterization of mitosis in the patients' cells. Analyses of chromosome nondisjunction in T-lymphocytes and fibroblasts revealed a significantly elevated rate of nondisjunction in the patients' cells as compared to controls. Mitotic progression was further explored by immunofluorescence analyses of several chromosome and spindle associated proteins. We detected a remarkable alteration in the anaphase distribution of Aurora B and INCENP, which are key regulators of chromosome segregation. In particular, a fraction of both proteins remained abnormally loaded on chromosomes during anaphase in MCPH patients' cells while in cells of normal control subjects both proteins are completely transferred to the spindle midzone. We did not observe any other alterations regarding cell cycle progression, chromosome structure, or response to DNA damage. Our observations point towards a molecular role of the underlying gene product in the regulation of anaphase/telophase progression possibly through interaction with chromosomal passenger proteins. In addition, our findings represent further evidence for the proposed role of MCPH genes in the regulation of mitotic progression