65 research outputs found

    Acute Cholecystitis Is a Common Complication after Allogeneic Stem Cell Transplantation and Is Associated with the Use of Total Parenteral Nutrition

    Get PDF
    AbstractThe incidence and risk factors for acute cholecystitis after allogeneic hematopoietic stem cell transplantation (HSCT) are not well defined. Of 644 consecutive adult transplants performed at our institution between 2001 and 2011, acute cholecystitis occurred in the first year of transplant in 32 patients (5.0%). We conducted 2 retrospective case-control studies of this population to determine risk factors for cholecystitis after HSCT and to evaluate the performance of different methods of imaging to diagnosis cholecystitis in patients undergoing HSCT compared with non-HSCT patients. In the HSCT population, development of cholecystitis was associated with an increased 1-year overall mortality rate (62.5% versus 19.8%, P < .001). The risk of developing cholecystitis was higher in patients who received total parenteral nutrition (TPN) (adjusted odds ratio, 3.41; P = .009). There was a trend toward more equivocal abdominal ultrasound findings in HSCT recipients with acute cholecystitis compared with nontransplant patients (50.0% versus 30.6%, P = .06). However, hepatobiliary iminodiacetic acid (HIDA) scans were definitively positive for acute cholecystitis in most patients in both populations (80.0% of HSCT recipients versus 77.4% of control subjects, P = .82). In conclusion, acute cholecystitis is a common early complication of HSCT, the risk is increased in patients who receive TPN, and it is associated with high 1-year mortality. In HSCT recipients with findings suggestive of acute cholecystitis, especially those receiving TPN, early use of HIDA scan may be considered over ultrasound

    Antigen glycosylation regulates efficacy of CAR T cells targeting CD19

    Get PDF
    While chimeric antigen receptor (CAR) T cells targeting CD19 can cure a subset of patients with B cell malignancies, most patients treated will not achieve durable remission. Identification of the mechanisms leading to failure is essential to broadening the efficacy of this promising platform. Several studies have demonstrated that disruption of CD19 genes and transcripts can lead to disease relapse after initial response; however, few other tumor-intrinsic drivers of CAR T cell failure have been reported. Here we identify expression of the Golgi-resident intramembrane protease Signal peptide peptidase-like 3 (SPPL3) in malignant B cells as a potent regulator of resistance to CAR therapy. Loss of SPPL3 results in hyperglycosylation of CD19, an alteration that directly inhibits CAR T cell effector function and suppresses anti-tumor cytotoxicity. Alternatively, over-expression of SPPL3 drives loss of CD19 protein, also enabling resistance. In this pre-clinical model these findings identify post-translational modification of CD19 as a mechanism of antigen escape from CAR T cell therapy

    The Metagenome of an Anaerobic Microbial Community Decomposing Poplar Wood Chips

    Get PDF
    This study describes the composition and metabolic potential of a lignocellulosic biomass degrading community that decays poplar wood chips under anaerobic conditions. We examined the community that developed on poplar biomass in a non-aerated bioreactor over the course of a year, with no microbial inoculation other than the naturally occurring organisms on the woody material. The composition of this community contrasts in important ways with biomass-degrading communities associated with higher organisms, which have evolved over millions of years into a symbiotic relationship. Both mammalian and insect hosts provide partial size reduction, chemical treatments (low or high pH environments), and complex enzymatic ‘secretomes’ that improve microbial access to cell wall polymers. We hypothesized that in order to efficiently degrade coarse untreated biomass, a spontaneously assembled free-living community must both employ alternative strategies, such as enzymatic lignin depolymerization, for accessing hemicellulose and cellulose and have a much broader metabolic potential than host-associated communities. This would suggest that such a community would make a valuable resource for finding new catalytic functions involved in biomass decomposition and gaining new insight into the poorly understood process of anaerobic lignin depolymerization. Therefore, in addition to determining the major players in this community, our work specifically aimed at identifying functions potentially involved in the depolymerization of cellulose, hemicelluloses, and lignin, and to assign specific roles to the prevalent community members in the collaborative process of biomass decomposition. A bacterium similar to Magnetospirillum was identified among the dominant community members, which could play a key role in the anaerobic breakdown of aromatic compounds. We suggest that these compounds are released from the lignin fraction in poplar hardwood during the decay process, which would point to lignin-modification or depolymerization under anaerobic conditions

    Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adults

    Get PDF
    Background Underweight and obesity are associated with adverse health outcomes throughout the life course. We estimated the individual and combined prevalence of underweight or thinness and obesity, and their changes, from 1990 to 2022 for adults and school-aged children and adolescents in 200 countries and territories. Methods We used data from 3663 population-based studies with 222 million participants that measured height and weight in representative samples of the general population. We used a Bayesian hierarchical model to estimate trends in the prevalence of different BMI categories, separately for adults (age ≥20 years) and school-aged children and adolescents (age 5–19 years), from 1990 to 2022 for 200 countries and territories. For adults, we report the individual and combined prevalence of underweight (BMI 2 SD above the median). Findings From 1990 to 2022, the combined prevalence of underweight and obesity in adults decreased in 11 countries (6%) for women and 17 (9%) for men with a posterior probability of at least 0·80 that the observed changes were true decreases. The combined prevalence increased in 162 countries (81%) for women and 140 countries (70%) for men with a posterior probability of at least 0·80. In 2022, the combined prevalence of underweight and obesity was highest in island nations in the Caribbean and Polynesia and Micronesia, and countries in the Middle East and north Africa. Obesity prevalence was higher than underweight with posterior probability of at least 0·80 in 177 countries (89%) for women and 145 (73%) for men in 2022, whereas the converse was true in 16 countries (8%) for women, and 39 (20%) for men. From 1990 to 2022, the combined prevalence of thinness and obesity decreased among girls in five countries (3%) and among boys in 15 countries (8%) with a posterior probability of at least 0·80, and increased among girls in 140 countries (70%) and boys in 137 countries (69%) with a posterior probability of at least 0·80. The countries with highest combined prevalence of thinness and obesity in school-aged children and adolescents in 2022 were in Polynesia and Micronesia and the Caribbean for both sexes, and Chile and Qatar for boys. Combined prevalence was also high in some countries in south Asia, such as India and Pakistan, where thinness remained prevalent despite having declined. In 2022, obesity in school-aged children and adolescents was more prevalent than thinness with a posterior probability of at least 0·80 among girls in 133 countries (67%) and boys in 125 countries (63%), whereas the converse was true in 35 countries (18%) and 42 countries (21%), respectively. In almost all countries for both adults and school-aged children and adolescents, the increases in double burden were driven by increases in obesity, and decreases in double burden by declining https://researchonline.ljmu.ac.uk/images/research_banner_face_lab_290.jpgunderweight or thinness. Interpretation The combined burden of underweight and obesity has increased in most countries, driven by an increase in obesity, while underweight and thinness remain prevalent in south Asia and parts of Africa. A healthy nutrition transition that enhances access to nutritious foods is needed to address the remaining burden of underweight while curbing and reversing the increase in obesity

    Natural killer cells in the graft versus host and graft versus tumour responses

    Get PDF
    Deposited with permission of the author. © 2012 Dr. Saar GillSince their description as agents of natural cytotoxicity more than 30 years ago, natural killer (NK) cells have generated great interest due to their ability to kill tumour cells in vitro in the absence of prior encounter or stimulation and without the need for antigen presentation. Animal studies have shown that depletion of NK cells leads to enhanced tumour growth, and these observations led to efforts to harness the anti-tumour effect of adoptively transferred “lymphokine activated killer” (LAK) cells some 20 years ago. Although LAK cells ultimately failed to deliver on their preclinical promise, exciting results in the field of haploidentical bone marrow transplantation then led to a resurgence of interest in the application of NK cell alloreactivity for the treatment of malignancy. Unlike T cells, allogeneic NK cells do not cause graft-versus-host disease (GVHD), providing further reassurance that NK cells could be safely transferred from allogeneic MHC-mismatched donors into patients. Indeed, recent efforts to re-infuse ex-vivo expanded autologous or allogeneic NK cells into patients with malignancy have been shown to be feasible and safe. However, conclusive evidence of clinical efficacy is still lacking. The main aim of this dissertation was to explore the barriers to successful NK cell anti-tumour immunotherapy, by tracing the fate of NK cells adoptively transferred into mice. A systematic approach was employed to interrogate each of the requisite steps in successful cellular therapy: Trafficking to tumour, accumulation, target recognition through cognate receptors, engagement of effector functions, and persistence of effector cells until all target cells are eliminated. Using several NK-sensitive mouse tumour models, in Chapter 3 NK cells were shown to be unable to mediate regression of established tumours or improve the survival of tumour-bearing mice, despite robust homing and accumulation within the tumour. This surprising observation implied that NK cells had become dysfunctional after transfer, and in Chapter 4 the transferred NK cells were shown to have down-regulated expression of activating receptors and reduced cytokine production and cytotoxic capacities. A molecular mechanism for this observation was provided by highlighting a concomitant down-regulation of the canonical NK cell transcription factor Eomesodermin, with partial correction of the dysfunctional phenotype after overexpression of this transcription factor in transferred NK cells. The acquired dysfunction was dependent on proliferation, which could be induced by homeostatic expansion or by exposure to tumour. Due to similarities with the process of CD8+ T cell exhaustion, this novel observation was termed “NK cell exhaustion”. Subsequently, adoptively transferred NK cells were found to exhibit anti- T cell immunity functions, impairing the function of tumour-specific T cells (Chapter 5) and mediating a reduction in T cell-mediated GVHD (Chapter 6), and suggesting that under certain conditions the role of NK cells switches from a predominantly inflammatory to a mostly immunoregulatory function, arguably a form of functional plasticity. These findings have clear implications for the field of NK cellular immunotherapy, explore important concepts in immunology, and will hopefully contribute to a future systematic evaluation of the transcriptional programs involved in NK cell exhaustion thus leading to a better understanding of the requirements for successful NK cellular immunotherapy

    Chimeric antigen receptor T-cell therapy for acute myeloid leukemia: how close to reality?

    No full text

    Cancer immunotherapy comes of age and looks for maturity

    No full text
    As Nature Communications celebrates a 10-year anniversary, the field has witnessed the transition of cancer immunotherapy from a pipe dream to an established powerful cancer treatment modality. Here we discuss the opportunities and challenges for the future
    corecore