The molecular rules driving TCR cross-reactivity are poorly understood and, consequently, it is unclear the extent to which TCRs targeting the same Ag recognize the same off-target peptides. We determined TCR-peptide-HLA crystal structures and, using a single-chain peptide-HLA phage library, we generated peptide specificity profiles for three newly identified human TCRs specific for the cancer testis Ag NY-ESO-1-HLA-A2. Two TCRs engaged the same central peptide feature, although were more permissive at peripheral peptide positions and, accordingly, possessed partially overlapping peptide specificity profiles.
View Article and Find Full Text PDFRobust preclinical testing is essential to predict clinical safety and efficacy and provide data to determine safe dose for first-in-man studies. There are a growing number of examples where the preclinical development of drugs failed to adequately predict clinical adverse events in part due to their assessment with inappropriate preclinical models. Preclinical investigations of T cell receptor (TCR)-based immunotherapies prove particularly challenging as these biologics are human-specific and thus the conventional testing in animal models is inadequate.
View Article and Find Full Text PDFOpen Forum Infect Dis
July 2018
Background: In April 2014, a 46-year-old returning traveler from Liberia was transported by emergency medical services to a community hospital in Minnesota with fever and altered mental status. Twenty-four hours later, he developed gingival bleeding. Blood samples tested positive for Lassa fever RNA by reverse transcriptase polymerase chain reaction.
View Article and Find Full Text PDFInfect Control Hosp Epidemiol
December 2016
OBJECTIVE To facilitate surveillance and describe the burden of healthcare-associated infection (HAI) in nursing homes (NHs), we compared the quality of resident-level data collected by NH personnel and external staff. DESIGN A 1-day point-prevalence survey SETTING AND PARTICIPANTS Overall, 9 nursing homes among 4 Centers for Disease Control and Prevention (CDC) Emerging Infection Program (EIP) sites were included in this study. METHODS NH personnel collected data on resident characteristics, clinical risk factors for HAIs, and the presence of 3 HAI screening criteria on the day of the survey.
View Article and Find Full Text PDFCarbapenemase-producing, carbapenem-resistant Enterobacteriaceae, or CP-CRE, are an emerging threat to human and animal health, because they are resistant to many of the last-line antimicrobials available for disease treatment. Carbapenemase-producing Enterobacter cloacae harboring blaKPC-3 recently was reported in the upper midwestern United States and implicated in a hospital outbreak in Fargo, North Dakota (L. M.
View Article and Find Full Text PDFHere, we describe a fatal serious adverse event observed in a patient infused with autologous T-cell receptor (TCR) transduced T cells. This TCR, originally obtained from a melanoma patient, recognizes the well-described HLA-A*0201 restricted 26-35 epitope of MART-1, and was not affinity enhanced. Patient 1 with metastatic melanoma experienced a cerebral hemorrhage, epileptic seizures, and a witnessed cardiac arrest 6 days after cell infusion.
View Article and Find Full Text PDFCarbapenem-resistant Enterobacteriaceae (CRE) are a growing problem in the United States. We explored the feasibility of active laboratory-based surveillance of CRE in a metropolitan area not previously considered to be an area of CRE endemicity. We provide a framework to address CRE surveillance and to monitor changes in the incidence of CRE infection over time.
View Article and Find Full Text PDFMAGE A3, which belongs to the family of cancer-testis antigens, is an attractive target for adoptive therapy given its reactivation in various tumors and limited expression in normal tissues. We developed an affinity-enhanced T cell receptor (TCR) directed to a human leukocyte antigen (HLA)-A*01-restricted MAGE A3 antigen (EVDPIGHLY) for use in adoptive therapy. Extensive preclinical investigations revealed no off-target antigen recognition concerns; nonetheless, administration to patients of T cells expressing the affinity-enhanced MAGE A3 TCR resulted in a serious adverse event (SAE) and fatal toxicity against cardiac tissue.
View Article and Find Full Text PDFAn obstacle to cancer immunotherapy has been that the affinity of T-cell receptors (TCRs) for antigens expressed in tumors is generally low. We initiated clinical testing of engineered T cells expressing an affinity-enhanced TCR against HLA-A*01-restricted MAGE-A3. Open-label protocols to test the TCRs for patients with myeloma and melanoma were initiated.
View Article and Find Full Text PDFDNA double-strand breaks (DSBs) are biologically one of the most important cellular lesions and possess varying degrees of chemical complexity. The notion that the repairability of more chemically complex DSBs is inefficient led to the concept that the extent of DSB complexity underlies the severity of the biological consequences. The repair of DSBs by non-homologous end joining (NHEJ) has been extensively studied but it remains unknown whether more complex DSBs require a different sub-set of NHEJ protein for their repair compared with simple DSBs.
View Article and Find Full Text PDFT cell immunity can potentially eradicate malignant cells and lead to clinical remission in a minority of patients with cancer. In the majority of these individuals, however, there is a failure of the specific T cell receptor (TCR)–mediated immune recognition and activation process. Here we describe the engineering and characterization of new reagents termed immune-mobilizing monoclonal TCRs against cancer (ImmTACs).
View Article and Find Full Text PDFEnterobacteriaceae that are resistant to multiple drugs are a public health concern and present a challenge to health care providers in terms of prevention and control. This article describes the changing resistance mechanisms that allow bacteria to circumvent antibiotics and how multidrug-resistant bacterial infections can spread within hospitals, among health care facilities, and across national borders. It also discusses the challenges associated with identifying and treating these infections and what health care providers need to do to prevent their transmission.
View Article and Find Full Text PDFA 44-year-old woman with long-standing common variable immunodeficiency who was receiving intravenous immune globulin suddenly had paralysis of all four limbs and the respiratory muscles, resulting in death. Type 2 vaccine-derived poliovirus was isolated from stool. The viral capsid protein VP1 region had diverged from the vaccine strain at 12.
View Article and Find Full Text PDFCellular lesions (e.g. DSBs) are induced into DNA upon exposure to radiation, with DSB complexity increasing with radiation ionization density.
View Article and Find Full Text PDFDNA Repair (Amst)
August 2010
When cells are exposed to radiation serious lesions are introduced into the DNA including double strand breaks (DSBs), single strand breaks (SSBs), base modifications and clustered damage sites (a specific feature of ionizing radiation induced DNA damage). Radiation induced DNA damage has the potential to initiate events that can lead ultimately to mutations and the onset of cancer and therefore understanding the cellular responses to DNA lesions is of particular importance. Using gammaH2AX as a marker for DSB formation and RAD51 as a marker of homologous recombination (HR) which is recruited in the processing of frank DSBs or DSBs arising from stalled replication forks, we have investigated the contribution of SSBs and non-DSB DNA damage to the induction of DSBs in mammalian cells by ionizing radiation during the cell cycle.
View Article and Find Full Text PDFIn Minnesota, incidence of invasive group B streptococcal disease was 3 times greater in older adults in long-term care facilities than in older adults in community settings (67.7/100,000 vs. 21.
View Article and Find Full Text PDFCell signaling initiated at the epidermal growth factor receptor (EGFR), RAS oncoproteins, or PI3K contributes to a common pathway that promotes tumor survival after radiation-induced DNA damage. Inhibition of signaling at the level of EGFR, RAS, and PI3K has been tested, but clinical applicability has been shown only at the level of the EGFR or by inhibiting RAS indirectly with prenyltransferase inhibitors. Inhibition of PI3K with LY294002 or wortmannin lacks specificity and has shown unacceptable toxicity in preclinical studies.
View Article and Find Full Text PDFDNA double strand breaks (DSBs) are amongst the most deleterious lesions induced within the cell following exposure to ionizing radiation. Mammalian cells repair these breaks predominantly via the nonhomologous end joining pathway which is active throughout the cell cycle and is error prone. The alternative pathway for repair of DSBs is homologous recombination (HR) which is error free and active during S- and G2/M-phases of the cell cycle.
View Article and Find Full Text PDFWe developed a biochemical kinetics approach to describe the repair of double-strand breaks (DSBs) produced by low-LET radiation by modeling molecular events associated with non-homologous end joining (NHEJ). A system of coupled nonlinear ordinary differential equations describes the induction of DSBs and activation pathways for major NHEJ components including Ku70/80, DNA-PKcs, and the ligase IV-XRCC4 heterodimer. The autophosphorylation of DNA-PKcs and subsequent induction of gamma-H2AX foci observed after ionizing radiation exposure were modeled.
View Article and Find Full Text PDFJ Am Geriatr Soc
August 2007
Objectives: To describe current systems used to track infections, antibiotic use, and antibiotic-resistant infections in Minnesota long-term care facilities (LTCFs).
Design: Self-administered multiple-choice survey assessing the methods, frequency, content, and dissemination of information used to track infections and antibiotic use.
Setting: Licensed Minnesota LTCFs providing skilled nursing care to geriatric residents as of June 2005.
Hyperglycaemia occurs in the majority of critically-ill patients, partly because patients are hypercatabolic and consequently have increased glucose levels and partly because of insulin resistance. Hyperglycaemia is associated with increased mortality in critical illness. In 2001 it was shown that mortality and other complications of critical illness can be decreased by adopting 'tight' glycaemic control (4.
View Article and Find Full Text PDFPurpose: To investigate quantitatively the induction and rejoining of DNA double strand breaks (DSB) in V79-4 and xrs-5 Chinese hamster cells and HF19 human fibroblast cells, using the phosphorylation of the histone protein H2AX (gamma-H2AX) as an indicator of DSB, exposed to low doses of either low linear energy transfer (LET) (60)Co gamma-rays or high LET a-particles.
Materials And Methods: Cells were irradiated with low or high LET (20 - 2000 mGy). The gamma-H2AX foci were detected using immunohistochemistry and quantified by image analysis.
Methods Mol Biol
March 2005
The method described in the following chapter utilizes a double thymidine block (an inhibitor of DNA synthesis) followed by treatment of cells with nocodazole (a mitotic inhibitor) to obtain large cell populations at distinct phases of the cell cycle. Treatment with double thymidine results in a G1/S-phase arrested cell population, and the use of flow cytometry allows progression of the cells through the cell cycle to be monitored. Flow cytometry enables the calculation of timings for collection of cells at distinct cell cycle phases from G1/S (following treatment with thymidine) through to G2/M (owing to the presence of nocodazole).
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