Abstract Current screening methods have poor specificity and sensitivity for detecting cardiac abnormalities that predispose young athletes to sudden death. Natriuretic peptides (NPs) show promise in ...screening asymptomatic populations for structural heart disease, but little is known about their use in student athletes. This study sought to describe the distribution and characteristics of NP levels in a population of college athletes and determine the relationship between NPs and the pre-participation exam (PPE) and hand-held echocardiography (HHE). We evaluated 457 college varsity athletes with B-type NP (BNP) and N-terminal proBNP (NT-proBNP) levels and a standard PPE; 200 also underwent HHE. NT-proBNP and BNP levels were highly correlated ( r = 0.87, p < 0.001), with a median of 21 pg/ml and 8 pg/ml respectively. 95% of athletes had NT-proBNP < 84 pg/ml and 95% had BNP < 33 pg/ml. Levels were higher in athletes with a history of exertional dizziness/syncope but did not correlate with other elements of the PPE or with HHE, although no major cardiac structural abnormalities were identified in this population. In men, there were weak correlations between NP levels and number of days per week performing distance running, strenuous exercise, or sprinting. In conclusion, NPs are only weakly correlated with intensity of physical training, and most college athletes have low NP levels; further studies are needed to elucidate the significance of elevated NP levels in this population, as they may provide incremental information beyond that provided by the PPE and echocardiography.
Abstract
While immune checkpoint inhibitors (ICIs) have revolutionized cancer therapy, only a small percentage of patients demonstrate therapeutic response. Understanding the cellular and molecular ...mechanism of action of ICIs could help identify novel biomarkers of ICI response and therefore select patients who are more likely to obtain a clinically durable response. To identify the unknown molecular interactions between cancer and immune cells that shape therapeutic response, we leveraged single-cell RNA-sequencing (scRNA-seq) of CD45+ intratumoral cells in a preclinical sarcoma model. Our unsupervised learning method CoGAPS detected gene signatures associated with distinct cellular responses to anti-PD-1 and anti-CTLA-4 treatment, either monotherapy or in combination. Notably, this analysis identified unanticipated synergy between PD1 and CTLA4 blockade in combination, including upregulation of antigen presentation and downregulation of regulatory T cell pathways. A subset of dual treated immune cells also revealed a signature consisting of autoimmune and steroidogenic genes, which we hypothesize may be involved in immune related adverse effects.
Annotating the cellular landscape of these molecular patterns identified novel interactions between NK cells and CTLA4 blockade. Importantly, NK cells in the monotherapy treated group showed upregulation of granzymes and perforin, suggesting enhanced activation and degranulation as a mechanism of ICI response. To examine the relevance of this signature in humans, we first assessed the correlation between CTLA4 expression and CIBERSORT cell type classification in cancers FDA approved for ICI therapy from The Cancer Genome Atlas. This revealed a positive correlation between CTLA4 and NK cell activation. RT-qPCR and western blot analysis in human NK cell lines and donor cells confirmed CTLA4 expression. We are currently expanding these results to assess the functional role of CTLA4 in the anti-tumor response of human NK cells during ICI treatment. Additionally, we relate learned therapeutic response signatures to patients through our transfer learning method, projectR. We queried the occurrence of our preclinical signatures in scRNA-seq of human CD45+ intratumoral cells collected from 48 ICI treated melanoma patients. The NK signature was highest in patients responsive to CTLA4 blockade, either single or dual ICI. We also identified T cell specific transcriptional signatures associated with upregulation of T cell trafficking and proliferation pathways enriched in patients who were responsive to ICI. Notably, these signatures were present prior to treatment, indicating their potential to predict clinical responders to ICI. Collectively, our data identify clinically relevant cellular perturbations in ICI responders and contribute to our mechanistic understanding of ICI response.
Citation Format: Emily F. Davis-Marcisak, Allison A. Fitzgerald, Neeha Zaidi, Elizabeth M. Jaffee, Louis M. Weiner, Elana J. Fertig. Transfer learning identifies common cellular determinants of immune checkpoint inhibitor response between preclinical tumor models and patients abstract. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3413.
Immunotherapy has revolutionized cancer treatment. Certain immunotherapies, such as immune checkpoint inhibitors and CAR-T cell therapy, provide long lasting remissions. Unfortunately, the majority ...of tumors are unresponsive to immunotherapy and tumors that initially respond frequently develop resistance. In order to improve patient clinical outcomes a greater understanding of anti-tumor immunology is required to broaden and refine immunotherapy treatment. While there are two types of cytotoxic lymphocytes that kill malignant cells, CD8+ T cells and natural killer (NK) cells, NK cells are under-studied in comparison to CD8+ T cells. In this dissertation, I explore multiple ways to enhance NK cell anti-cancer properties. In cancer, patients with high tumoral NK cell content and activation have improved survival and response to immunotherapy. Because of this, NK cells are emerging as major targets to promote cancer immunotherapy. Current NK-focused immunotherapy approaches include autologous or allogenic NK cell transfer, CAR-NK cells, NK immune checkpoint inhibitors, bi- or tri-specific killer engagers (BiKEs and TriKES), and cytokine super-agonists. An impediment to all these therapies is inadequate NK cell honing to and/or infiltration into solid tumors. The first part of this dissertation describes approaches to enhance NK cell tumor honing and infiltration, either through pharmacologic means or by genetic engineering. Specifically, I detail 1) that NK cells express fibroblast activation protein (FAP) which regulates NK cell tumor infiltration (chapters 1, 2, 4 and 5) and 2) how a dipeptidyl peptidase inhibitor, which inhibits FAP and other members of the dipeptidyl peptidase family, enhances NK cell tumor infiltration and increases anti-PD-1 efficacy (chapter 3). Once NK cells enter the tumor milieu, they can become exhausted, limiting their anti-tumor potential. NK cell exhaustion is marked by upregulation of immune checkpoints. While PD-1 and CTLA-4 are immune checkpoints expressed by exhausted T cells, their expression and functionality in NK cells is controversial. In chapter 6, I demonstrate human NK cells express CTLA-4 and suggest anti-CTLA-4 immune checkpoint therapy may restore NK cell function leading to tumoral NK cell activation. In sum, this dissertation describes multiple novel approaches to altering NK cell biology to enhance their anti-tumor activity and potentially improve patient outcomes.
One of the most common urologic problems afflicting millions of people worldwide is urinary tract infection (UTI). The severity of UTIs ranges from asymptomatic bacteriuria to acute cystitis, and in ...severe cases, pyelonephritis and urosepsis. The primary cause of UTIs is uropathogenic
(UPEC), for which current antibiotic therapies often fail. UPEC forms multicellular communities known as biofilms on urinary catheters, as well as on and within bladder epithelial cells. Biofilm formation protects UPEC from environmental conditions, antimicrobial therapy, and the host immune system. Previous studies have investigated UPEC biofilm formation in aerobic conditions (21% oxygen); however, urine oxygen tension is reduced (4-6%), and urine contains molecules that can be used by UPEC as alternative terminal electron acceptors (ATEAs) for respiration. This study was designed to determine whether these different terminal electron acceptors utilized by
influence biofilm formation. A panel of 50 urine-associated
isolates was tested for the ability to form biofilm under anaerobic conditions and in the presence of ATEAs. Biofilm production was reduced under all tested sub-atmospheric levels of oxygen, with the notable exception of 4% oxygen, the reported concentration of oxygen within the bladder.
We present a series of 6 critically ill children with multisystem inflammatory syndrome in children. Key findings of this syndrome include fever, diarrhea, shock, and variable presence of rash, ...conjunctivitis, extremity edema, and mucous membrane changes.
Significance Systemic lupus erythematosus (SLE) is a chronic systemic autoimmune disease that presents with a diverse array of clinical symptoms and afflicts over 1.5 million Americans. Current ...treatments involve immunosuppressive regimens associated with debilitating and adverse effects. With the description of a role for innate signaling in SLE, safe and efficient therapies that block Toll-like receptors also have been stymied by the relative short in vivo half lives of known inhibitors and the dangerous outcome of complete MyD88 blockade. Key natural regulators of the disease process are not well described but are more likely to provide disease-specific therapeutics with fewer adverse effects. In this study, we have identified a novel function for Stimulator of interferon genes as a suppressor of disease and a target for future SLE therapeutics.
Cytosolic DNA-sensing pathways that signal via Stimulator of interferon genes (STING) mediate immunity to pathogens and also promote autoimmune pathology in DNaseII- and DNaseIII-deficient mice. In contrast, we report here that STING potently suppresses inflammation in a model of systemic lupus erythematosus (SLE). Lymphoid hypertrophy, autoantibody production, serum cytokine levels, and other indicators of immune activation were markedly increased in STING-deficient autoimmune-prone mice compared with STING-sufficient littermates. As a result, STING-deficient autoimmune-prone mice had significantly shorter lifespans than controls. Importantly, Toll-like receptor (TLR)-dependent systemic inflammation during 2,6,10,14-tetramethylpentadecane (TMPD)-mediated peritonitis was similarly aggravated in STING-deficient mice. Mechanistically, STING-deficient macrophages failed to express negative regulators of immune activation and thus were hyperresponsive to TLR ligands, producing abnormally high levels of proinflammatory cytokines. This hyperreactivity corresponds to dramatically elevated numbers of inflammatory macrophages and granulocytes in vivo. Collectively these findings reveal an unexpected negative regulatory role for STING, having important implications for STING-directed therapies.
Urbanization and human-led development have increased more rapidly along shorelines and in coastal watersheds than inland regions over the past century. The result of major land use changes for both ...urban tracts and agriculture to serve the urban areas, as well as infrastructure development is increased runoff carrying sediments, nutrients, pollutants, pharmaceuticals, and toxins downstream to estuarine systems. The increased runoff levels are only the tip of the iceberg, with human development resulting in increased fecal bacteria from urbanization and excess nutrients from agriculture leading to harmful algal blooms. Estuaries act as a natural filter between land and sea, but have been overloaded by the influx of sediments and pollutants in recent decades. As a result, there have been a variety of impacts to estuarine ecosystems and water quality including increased sediment load, eutrophication, harmful algal blooms, fecal bacteria, as well as shellfish and fisheries declines. In some estuarine systems, the reduction in light penetration to the benthos has led to the loss of seagrasses. In others, seasonal hypoxia is a visible symptom of prolonged eutrophication. There is a need to augment long-term monitoring techniques with new technologies and data processing methods to better understand the current state of estuaries and work towards mitigating human impacts on estuarine ecosystems and water quality.
The phylum Deinococcus-Thermus is a deeply-branching lineage of bacteria widely recognized as one of the most extremophilic. Members of the Thermus genus are of major interest due to both their ...bioremediation and biotechnology potentials. However, the molecular mechanisms associated with these key metabolic pathways remain unknown. Reverse-transcription quantitative PCR (RT-qPCR) is a high-throughput means of studying the expression of a large suite of genes over time and under different conditions. The selection of a stably-expressed reference gene is critical when using relative quantification methods, as target gene expression is normalized to expression of the reference gene. However, little information exists as to reference gene selection in extremophiles. This study evaluated 11 candidate reference genes for use with the thermophile Thermus scotoductus when grown under different culture conditions. Based on the combined stability values from BestKeeper and NormFinder software packages, the following are the most appropriate reference genes when comparing: (1) aerobic and anaerobic growth: TSC_c19900, polA2, gyrA, gyrB; (2) anaerobic growth with varied electron acceptors: TSC_c19900, infA, pfk, gyrA, gyrB; (3) aerobic growth with different heating methods: gyrA, gap, gyrB; (4) all conditions mentioned above: gap, gyrA, gyrB. The commonly-employed rpoC does not serve as a reliable reference gene in thermophiles, due to its expression instability across all culture conditions tested here. As extremophiles exhibit a tendency for polyploidy, absolute quantification was employed to determine the ratio of transcript to gene copy number in a subset of the genes. A strong negative correlation was found to exist between ratio and threshold cycle (CT) values, demonstrating that CT changes reflect transcript copy number, and not gene copy number, fluctuations. Even with the potential for polyploidy in extremophiles, the results obtained via absolute quantification indicate that relative quantification is appropriate for RT-qPCR studies with this thermophile.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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