The Role of Atypical Chemokine Receptors in Neuroinflammation and Neurodegenerative Disorders

Neuroinflammation is associated with several neurodegenerative disorders, including Alzheimer's disease (AD), Parkinson's disease (PD), and multiple sclerosis (MS). Neuroinflammation provides protection in acute situations but results in significant damage to the nervous system if chronic. Overexpression of chemokines within the brain results in the recruitment and activation of glial and peripheral immune cells which can propagate a cascading inflammatory response, resulting in neurodegeneration and the onset of neurodegenerative disorders. Recent work has identified the role of atypical chemokine receptors (ACKRs) in neurodegenerative conditions. ACKRs are seven-transmembrane domain receptors that do not follow canonical G protein signaling, but regulate inflammatory responses by modulating chemokine abundance, location, and availability. This review summarizes what is known about the four ACKRs and three putative ACKRs within the brain, highlighting their known expression and discussing the current understanding of each ACKR in the context of neurodegeneration. The ability of ACKRs to alter levels of chemokines makes them an appealing therapeutic target for neurodegenerative conditions. However, further work is necessary to understand the expression of several ACKRs within the neuroimmune system and the effectiveness of targeted drug therapies in the prevention and treatment of neurodegenerative conditions.

A Novel Application of Spinning Disk Technology to Collect Plasma from Whole Blood Prior to Quantifying Plasma RNA

The spinning disk technology has previously been utilized to isolate bacterial components from blood in hours instead of days. We hypothesized that this platform could be applied as an alternative approach to isolating plasma RNA from a whole blood sample. We consequently tested the efficacy of the spinning disk technology to extract plasma from whole blood upstream of RNA isolation and analysis. To do so, we collected plasma using either the spinning disk or the typical two-spin centrifuge method. We found that the spinning disk method results in significantly more hemolysis during collection than the conventional two-spin centrifuge method. However, when plasma RNA recovered from both collection methods was quantified using quantitative Real-Time Polymerase Chain Reaction (qRT-PCR), we found that the spinning disk method yielded a higher plasma RNA concentration than the two-spin centrifuge method. This suggests that the spinning disk may be an efficient alternative method to recover plasma RNA. Further work is needed to determine whether red blood cell RNA contamination is present in the plasma RNA extracted from spinning disk-processed plasma.

Interleukin-10 enhances activity of ventral tegmental area dopamine neurons resulting in increased dopamine release

Dopamine transmission from the ventral tegmental area (VTA) to the nucleus accumbens (NAc) regulates important aspects of motivation and is influenced by the neuroimmune system. The neuroimmune system is a complex network of leukocytes, microglia and astrocytes that detect and remove foreign threats like bacteria or viruses and communicate with each other to regulate non-immune (e.g neuronal) cell activity through cytokine signaling. Inflammation is a key regulator of motivational states, though the effects of specific cytokines on VTA circuitry and motivation are largely unknown. Therefore, electrophysiology, neurochemical, immunohistochemical and behavioral studies were performed to determine the effects of the anti-inflammatory cytokine interleukin-10 (IL-10) on mesolimbic activity, dopamine transmission and conditioned behavior. IL-10 enhanced VTA dopamine firing and NAc dopamine levels via decreased VTA GABA currents in dopamine neurons. The IL-10 receptor was localized on VTA dopamine and non-dopamine cells. The IL-10 effects on dopamine neurons required post-synaptic phosphoinositide 3-kinase activity, and IL-10 appeared to have little-to-no efficacy on presynaptic GABA terminals. Intracranial IL-10 enhanced NAc dopamine levels in vivo and produced conditioned place aversion. Together, these studies identify the IL-10R on VTA dopamine neurons as a potential regulator of motivational states.

Characterizing the Interplay of Lymphocytes in Graves' Disease

Graves' disease (GD) is a thyroid-specific autoimmune disease with a high prevalence worldwide. The disease is primarily mediated by B cells, which produce autoantibodies against the thyroid-stimulating hormone receptor (TSHR), chronically stimulating it and leading to high levels of thyroid hormones in the body. Interest in characterizing the immune response in GD has motivated many phenotyping studies. The immunophenotype of the cells involved and the interplay between them and their secreted factors are crucial to understanding disease progression and future treatment options. T cell populations are markedly distinct, including increased levels of Th17 and follicular helper T cells (Tfh), while Treg cells appear to be impaired. Some B cells subsets are autoreactive, and anti-TSHR antibodies are the key disease-causing outcome of this interplay. Though some consensus across phenotyping studies will be discussed here, there are also complexities that are yet to be resolved. A better understanding of the immunophenotype of Graves' disease can lead to improved treatment strategies and novel drug targets.

A Chromosome-length Assembly of the Black Petaltail (Tanypteryx hageni) Dragonfly

We present a chromosome-length genome assembly and annotation of the Black Petaltail dragonfly (Tanypteryx hageni). This habitat specialist diverged from its sister species over 70 million years ago, and separated from the most closely related Odonata with a reference genome 150 million years ago. Using PacBio HiFi reads and Hi-C data for scaffolding we produce one of the most high-quality Odonata genomes to date. A scaffold N50 of 206.6 Mb and a single copy BUSCO score of 96.2% indicate high contiguity and completeness.

Immunomodulatory role of oral microbiota in inflammatory diseases and allergic conditions

In recent years, the interplay between oral microbiota and systemic disease has gained attention as poor oral health is associated with several pathologies. The oral microbiota plays a role in the maintenance of overall health, and its dysbiosis influences chronic inflammation and the pathogenesis of gum diseases. Periodontitis has also been associated with other diseases and health complications such as cancer, neurogenerative and autoimmune disorders, chronic kidney disease, cardiovascular diseases, rheumatic arthritis, respiratory health, and adverse pregnancy outcomes. The host microbiota can influence immune cell development and immune responses, and recent evidence suggests that changes in oral microbiota composition may also contribute to sensitization and the development of allergic reactions, including asthma and peanut allergies. Conversely, there is also evidence that allergic reactions within the gut may contribute to alterations in oral microbiota composition. Here we review the current evidence of the role of the oral microbiota in inflammatory diseases and health complications, as well as its future relevance in improving health and ameliorating allergic disease.

Bioaerosol and microbial exposures from residential evaporative coolers and their potential health outcomes: A review

Evaporative cooling is an energy efficient form of air conditioning in dry climates that functions by pulling hot, dry outdoor air across a wet evaporative pad. While evaporative coolers can help save energy, they also have the potential to influence human health. Studies have shown residential evaporative coolers may pull outdoor air pollutants into the home or contribute to elevated levels of indoor bioaerosols that may be harmful to health. There is also evidence that evaporative coolers can enable a diverse microbial environment that may confer early-life immunological protection against the development of allergies and asthma or exacerbate these same hypersensitivities. This review summarizes the current knowledge of bioaerosol and microbiological studies associated with evaporative coolers, focusing on harmful and potentially helpful outcomes from their use. We evaluate the effects of evaporative coolers on indoor bacterial endotoxins, fungal β-(1 → 3)-D-glucans, dust mite antigens, residential microbial communities, and Legionella pneumophila. To our knowledge, this is the first review to summarize and evaluate studies on the influence that evaporative coolers have on the bioaerosol and microbiological profile of homes. This brings to light a gap in the literature on evaporative coolers, which is the lack of data on health effects associated with their use.

Alphaviruses: Host pathogenesis, immune response, and vaccine & treatment updates

Human pathogens belonging to the Alphavirus genus, in the Togaviridae family, are transmitted primarily by mosquitoes. The signs and symptoms associated with these viruses include fever and polyarthralgia, defined as joint pain and inflammation, as well as encephalitis. In the last decade, our understanding of the interactions between members of the alphavirus genus and the human host has increased due to the re-appearance of the chikungunya virus (CHIKV) in Asia and Europe, as well as its emergence in the Americas. Alphaviruses affect host immunity through cytokines and the interferon response. Understanding alphavirus interactions with both the innate immune system as well as the various cells in the adaptive immune systems is critical to developing effective therapeutics. In this review, we summarize the latest research on alphavirus-host cell interactions, underlying infection mechanisms, and possible treatments.

CD4 Inhibits Helper T Cell Activation at Lower Affinity Threshold for Full-Length T Cell Receptors Than Single Chain Signaling Constructs

CD4⁺ T cells are crucial for effective repression and elimination of cancer cells. Despite a paucity of CD4⁺ T cell receptor (TCR) clinical studies, CD4⁺ T cells are primed to become important therapeutics as they help circumvent tumor antigen escape and guide multifactorial immune responses. However, because CD8⁺ T cells directly kill tumor cells, most research has focused on the attributes of CD8⁺ TCRs. Less is known about how TCR affinity and CD4 expression affect CD4⁺ T cell activation in full length TCR (flTCR) and TCR single chain signaling (TCR-SCS) formats. Here, we generated an affinity panel of TCRs from CD4⁺ T cells and expressed them in flTCR and three TCR-SCS formats modeled after chimeric antigen receptors (CARs) to understand the contributions of TCR-pMHCII affinity, TCR format, and coreceptor CD4 interactions on CD4⁺ T cell activation. Strikingly, the coreceptor CD4 inhibited intermediate and high affinity TCR-construct activation by Lck-dependent and -independent mechanisms. These inhibition mechanisms had unique affinity thresholds dependent on the TCR format. Intracellular construct formats affected the tetramer staining for each TCR as well as IL-2 production. IL-2 production was promoted by increased TCR-pMHCII affinity and the flTCR format. Thus, CD4⁺ T cell therapy development should consider TCR affinity, CD4 expression, and construct format.

Exposome and Immunity Training: How Pathogen Exposure Order Influences Innate Immune Cell Lineage Commitment and Function

Immune memory is a defining characteristic of adaptive immunity, but recent work has shown that the activation of innate immunity can also improve responsiveness in subsequent exposures. This has been coined “trained immunity” and diverges with the perception that the innate immune system is primitive, non-specific, and reacts to novel and recurrent antigen exposures similarly. The “exposome” is the cumulative exposures (diet, exercise, environmental exposure, vaccination, genetics, etc.) an individual has experienced and provides a mechanism for the establishment of immune training or immunotolerance. It is becoming increasingly clear that trained immunity constitutes a delicate balance between the dose, duration, and order of exposures. Upon innate stimuli, trained immunity or tolerance is shaped by epigenetic and metabolic changes that alter hematopoietic stem cell lineage commitment and responses to infection. Due to the immunomodulatory role of the exposome, understanding innate immune training is critical for understanding why some individuals exhibit protective phenotypes while closely related individuals may experience immunotolerant effects (e.g., the order of exposure can result in completely divergent immune responses). Research on the exposome and trained immunity may be leveraged to identify key factors for improving vaccination development, altering inflammatory disease development, and introducing potential new prophylactic treatments, especially for diseases such as COVID-19, which is currently a major health issue for the world. Furthermore, continued exposome research may prevent many deleterious effects caused by immunotolerance that frequently result in host morbidity or mortality.

Obesity and CD8 T cell metabolism: Implications for anti-tumor immunity and cancer immunotherapy outcomes

Obesity is an established risk factor for many cancers and has recently been found to alter the efficacy of T cell-based immunotherapies. Currently, however, the effects of obesity on immunometabolism remain unclear. Understanding these associations is critical, given the fact that T cell metabolism is tightly linked to effector function. Thus, any obesity-associated changes in T cell bioenergetics are likely to drive functional changes at the cellular level, alter the metabolome and cytokine/chemokine milieu, and impact cancer immunotherapy outcomes. Here, we provide a brief overview of T cell metabolism in the presence and absence of solid tumor growth and summarize current literature regarding obesity-associated changes in T cell function and bioenergetics. We also discuss recent findings related to the impact of host obesity on cancer immunotherapy outcomes and present potential mechanisms by which T cell metabolism may influence therapeutic efficacy. Finally, we describe promising pharmaceutical therapies that are being investigated for their ability to improve CD8 T cell metabolism and enhance cancer immunotherapy outcomes in patients, regardless of their obesity status.

Novel monoclonal antibodies against thymidine kinase 1 and their potential use for the immunotargeting of lung, breast and colon cancer cells

BACKGROUND

Thymidine kinase 1 (TK1) is a pyrimidine salvage pathway enzyme that is up-regulated in malignant tissues and elevated in the serum of cancer patients. While TK1 has been well established as a tumor biomarker, little has been done to explore its potential as a tumor target. Recently, we reported the membrane expression of TK1 on malignant cells, but not on normal cells. This study explores the possible use of monoclonal antibodies for the targeting of membrane associated TK1 in lung, breast, colon and prostate cancer cells.

METHODS

We generated and evaluated a panel of monoclonal antibodies against six different epitopes exposed in the tetrameric form of TK1. Antibodies were developed with hybridoma technology and validated with Western blot, siRNA TK1 knockdown, enzyme-linked immunosorbent assay (ELISA) and flow cytometry. The therapeutic potential of the antibodies was evaluated in vitro in antibody-dependent cell-mediated-cytotoxicity (ADCC) experiments.

RESULTS

Binding of the antibodies to TK1 was confirmed by Western blot in purified recombinant protein, cancer serum, and cell lysate. After a TK1 knockdown was performed, a reduction of TK1 expression was observed with five antibodies. Using indirect ELISA, we identified 3B2E11, 9C10, 7H2, 3B4, 8G2 among the most sensitive antibodies (LOD = 10.73-66.9 pg/ml). Surface expression of TK1 on the membrane of various cancer cell lines was analyzed with flow cytometry. Antibodies 8G2, 3B4, 7HD and 5F7G11 detected TK1 on the membrane of various cancer cell lines, including lung, prostate, colon and breast. No significant binding was detected on normal lymphocytes. Increased cytolysis of lung (~ 70%. p = 0.0001), breast (~ 70%, p = 0.0461) and colon (~ 50% p = 0.0216) cancer cells by effector cells was observed when anti-TK1 antibodies were added during ADCC experiments.

CONCLUSIONS

The antibodies developed showed potential to be used to detect and target TK1 on the membrane of various tumor cells. The targeting of TK1 in malignant cells using monoclonal antibodies may be a feasible approach for the elimination of high TK1 expressing tumor cells.

Hypoxanthine Guanine Phosphoribosyltransferase expression is negatively correlated with immune activity through its regulation of purine synthesis

INTRODUCTION

The purpose of this study was to examine the effects of elevated Hypoxanthine Guanine Phosphoribosyltransferase (HPRT) on the immune response in the tumor microenvironment.

METHODOLOGY

HPRT expression was evaluated in cancer patients and correlated with cytokine expression, survival, and immune cell infiltration. An HPRT knockdown cell line was created to evaluate HPRT impact on purine expression and subsequent purine treatment was administered to immune cells to determine their influence on cell activation.

RESULTS

HPRT expression was negatively correlated with the general expression of both pro-inflammatory and anti-inflammatory cytokines. Additionally, HPRT expression was also negatively correlated with the infiltration of immune cell subsets: B-cells, CD4 + T cells, macrophages, neutrophils, and dendritic cells (p < 0.001) and CD8 + T-cells (p < 0.01). When HPRT was knocked down in a Raji cell line, the levels of adenosine were reduced significantly compared to the wild type. When examining the level of Ca2+ influx of Raji compared to the HPRT Raji knockdown cell, there was a significant decrease in calcium influx in the knockdown cells when compared to the wild type cells. This demonstrates that HPRT had a significant impact on overall cell activation and the ability of the cells to properly influx calcium needed for their activation.

CONCLUSIONS

We conclude that purine levels significantly reduce immune cell activation in cancer and the upregulation of HPRT in malignant tissue is a contributing factors to the immunosuppressive microenvironment.

A full semester flow cytometry course improves graduate and undergraduate student confidence

Flow cytometry is a versatile and high throughput technique for rapid and efficient biological testing. It requires a high level of conceptual, technical, and analytical skills to properly design experiments, effectively operate flow cytometry machines, and analyze the data. A lack of training and development of any of these three skills can result in underutilization and improper use of flow cytometric machines that can impede research progress. Often students develop these conceptual, technical, and analysis skills from trial and error, but many students either do not use this powerful flow cytometry technology, use it improperly or ineffectively, or give up using it without proper training and support. Here we report on a course which teaches flow cytometry skills to undergraduate and graduate students. The design of this course is unique in that it teaches conceptual, technical, and analytical skills related to flow cytometry in a full semester format. Undergraduate and graduate students reported significant increases in their confidence levels over the course of the semester. Here we provide our findings and resources for others who may want to implement a similar course.

Genomics Education in the Era of Personal Genomics: Academic, Professional, and Public Considerations

Since the completion of the Human Genome Project in 2003, genomic sequencing has become a prominent tool used by diverse disciplines in modern science. In the past 20 years, the cost of genomic sequencing has decreased exponentially, making it affordable and accessible. Bioinformatic and biological studies have produced significant scientific breakthroughs using the wealth of genomic information now available. Alongside the scientific benefit of genomics, companies offer direct-to-consumer genetic testing which provide health, trait, and ancestry information to the public. A key area that must be addressed is education about what conclusions can be made from this genomic information and integrating genomic education with foundational genetic principles already taught in academic settings. The promise of personal genomics providing disease treatment is exciting, but many challenges remain to validate genomic predictions and diagnostic correlations. Ethical and societal concerns must also be addressed regarding how personal genomic information is used. This genomics revolution provides a powerful opportunity to educate students, clinicians, and the public on scientific and ethical issues in a personal way to increase learning. In this review, we discuss the influence of personal genomics in society and focus on the importance and benefits of genomics education in the classroom, clinics, and the public and explore the potential consequences of personal genomic education.

Associations between evaporative cooling and dust-mite allergens, endotoxins, and β-(1 → 3)-d-glucans in house dust: A study of low-income homes

Recent work suggests that evaporative coolers increase the level and diversity of bioaerosols, but this association remains understudied in low-income homes. We conducted a cross-sectional study of metropolitan, low-income homes in Utah with evaporative coolers (n = 20) and central air conditioners (n = 28). Dust samples (N = 147) were collected from four locations in each home and analyzed for dust-mite allergens Der p1 and Der f1, endotoxins, and β-(1 → 3)-d-glucans. In all sample locations combined, Der p1 or Der f1 was significantly higher in evaporative cooler versus central air conditioning homes (OR = 2.29, 95% CI = 1.05-4.98). Endotoxin concentration was significantly higher in evaporative cooler versus central air conditioning homes in furniture (geometric mean (GM) = 8.05 vs 2.85 EU/mg, P < .01) and all samples combined (GM = 3.60 vs 1.29 EU/mg, P = .03). β-(1 → 3)-d-glucan concentration and surface loads were significantly higher in evaporative cooler versus central air conditioning homes in all four sample locations and all samples combined (P < .01). Our study suggests that low-income, evaporative cooled homes have higher levels of immunologically important bioaerosols than central air-conditioned homes in dry climates, warranting studies on health implications and other exposed populations.

Abstract 2369: HPRT overexpression may contribute to the immunosuppressive tumor microenvironment

The purpose of this study was to examine the possible effects that Hypoxanthine Guanine Phosphoribosyltransferase (HPRT) may have on the immune response in the tumor microenvironment. HPRT is a salvage pathway enzyme responsible for recycling guanosine throughout the cell cycle, and we have shown that it is significantly upregulated in numerous solid malignancies. As a necessary component of the S phase in the cell cycle, guanosine has also been regarded as a potential neuroprotectant in the central nervous system (CNS). We thus hypothesized that there may be a correlation between the observed upregulation of HPRT and the relative downregulation of the immune system mediated by the differential regulation of guanosine. Using data from The Cancer Genome Atlas (TCGA), we analyzed over 200 cytokine genes and found a negative correlation between the level of HPRT expression in cancer and the general expression level of both pro-inflammatory and anti-inflammatory cytokine expression. We further analyzed data showing the relative infiltration level of individual immune cell subsets in solid tumors compared with elevated HPRT levels. We found the most significant negative correlations between HPRT expression and immune cell infiltration for B-cells (p &lt; 0.001), CD8+ T-cells (p &lt; 0.01), CD4+ T-cells (p &lt; 0.001), macrophages (p &lt; 0.001), neutrophils (p &lt; 0.001), and dendritic cells (p &lt; 0.001) in lung squamous cell carcinoma. Other significant negative correlations were found in kidney renal clear cell carcinoma, prostate adenocarcinoma, and breast invasive carcinoma. To further analyze this reduction in infiltration, we examined the relationship between HPRT expression and both costimulatory and coinhibitory molecules and found a significant negative correlation. Because of these observed associations between HPRT levels and cytokine expression, we hypothesized that the increased guanosine production was the mechanism by which HPRT was affecting the immune system in the tumor microenvironment. To test this, we examined the level of Ca2+ influx using Fluo-4 assays of B-cell (Raji), T-cell (Jurkat), and monocyte (THP-1) cell lines when treated with guanosine as a measure of overall cell activation. We then compared this activation to untreated cells and cells treated with adenosine, a known anti-inflammatory agent. When treated with guanosine, a significant reduction in activation was found in THP-1s (p &lt; 0.01) and Rajis (p &lt; 0.01), but not in Jurkats. However, under hypoxic and hypoglycemic conditions similar to those commonly found within the tumor microenvironment, Jurkat activation was significantly reduced (p &lt; 0.05) when treated with guanosine. From this data, we conclude that guanosine levels significantly reduce immune cell activation in the tumor microenvironment and that the upregulation of HPRT in malignant tissue may be one of the contributing factors of the immunosuppressive nature of the microenvironment.

Citation Format: Michelle H. Townsend, Zachary D. Ewell, Claudia M. Tellez Freitas, Dallas J. Larsen, Eliza L. Bitter, Kelsey B. Bennion, Stephen R. Piccolo, K Scott Weber, Richard A. Robison, Kim L. O'Neill. HPRT overexpression may contribute to the immunosuppressive tumor microenvironment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2369.

Effects of high affinity engineered class II-restricted full length and single chain CAR-format T cell receptors specific for a naturally occurring Listeria monocytogenes epitope on T cell activation and specificity

High affinity T cell receptors (TCRs) are absent from the native T cell repertoire. While current hypotheses propose that high affinity TCRs are more sensitive to antigen and have a competitive advantage in immune responses, emerging evidence suggests that higher affinity T cells may reach a threshold where they experience decreased functionality, loss of binding specificity, and become prone to anergy. High affinity TCRs are especially attractive to facilitate immunotherapies as native TCR binding affinity may be too low to effectively initiate activation. However, the effects of increased TCR affinity for CD4+ T cells specific for naturally occurring epitopes is poorly understood. To address this question, we engineered via yeast display several class II-restricted high affinity TCRs specific for a naturally occurring peptide from Listeria monocytogenes protein listeriolysin O. Our high affinity clones have KD values as low as 8.7 nM and half-lives as long as 174 minutes when measured by tetramer dissociation assays. This panel of class II restricted high affinity TCRs specific for a naturally occurring Listeria monocytogenes epitope provides a novel means of testing the role of affinity and CD4+ T cell activation responses in the context of an infection.

The nuclear variant of bone morphogenetic protein 2 (nBMP2) is expressed in macrophages and alters calcium response

We previously identified a nuclear variant of bone morphogenetic protein 2 (BMP2), named nBMP2, that is translated from an alternative start codon. Decreased nuclear localization of nBMP2 in the nBmp2NLS^tm mouse model leads to muscular, neurological, and immune phenotypes—all of which are consistent with aberrant intracellular calcium (Ca²⁺) response. Ca²⁺ response in these mice, however, has yet to be measured directly. Because a prior study suggested impairment of macrophage function in nBmp2NLS^tm mutant mice, bone marrow derived (BMD) macrophages and splenic macrophages were isolated from wild type and nBmp2NLS^tm mutant mice. Immunocytochemistry revealed that nuclei of both BMD and splenic macrophages from wild type mice contain nBMP2, while the protein is decreased in nuclei of nBmp2NLS^tm mutant macrophages. Live-cell Ca²⁺ imaging and engulfment assays revealed that Ca²⁺ response and phagocytosis in response to bacterial supernatant are similar in BMD macrophages isolated from naïve (uninfected) nBmp2NLS^tm mutant mice and wild type mice, but are deficient in splenic macrophages isolated from mutant mice after secondary systemic infection with Staphylococcus aureus, suggesting progressive impairment as macrophages respond to infection. This direct evidence of impaired Ca²⁺ handling in nBMP2 mutant macrophages supports the hypothesis that nBMP2 plays a role in Ca²⁺ response.

Common gut microbial metabolites of dietary flavonoids exert potent protective activities in β-cells and skeletal muscle cells

Flavonoids are dietary compounds with potential anti-diabetes activities. Many flavonoids have poor bioavailability and thus low circulating concentrations. Unabsorbed flavonoids are metabolized by the gut microbiota to smaller metabolites, which are more bioavailable than their precursors. The activities of these metabolites may be partly responsible for associations between flavonoids and health. However, these activities remain poorly understood. We investigated bioactivities of flavonoid microbial metabolites [hippuric acid (HA), homovanillic acid (HVA), and 5-phenylvaleric acid (5PVA)] in primary skeletal muscle and β-cells compared to a native flavonoid [(-)-epicatechin, EC]. In muscle, EC was the most potent stimulator of glucose oxidation, while 5PVA and HA simulated glucose metabolism at 25 μM, and all compounds preserved mitochondrial function after insult. However, EC and the metabolites did not uncouple mitochonndrial respiration, with the exception of 5PVA at10 μM. In β-cells, all metabolites more potently enhanced glucose-stimulated insulin secretion (GSIS) compared to EC. Unlike EC, the metabolites appear to enhance GSIS without enhancing β-cell mitochondrial respiration or increasing expression of mitochondrial electron transport chain components, and with varying effects on β-cell insulin content. The present results demonstrate the activities of flavonoid microbial metabolites for preservation of β-cell function and glucose utilization. Additionally, our data suggest that metabolites and native compounds may act by distinct mechanisms, suggesting complementary and synergistic activities in vivo which warrant further investigation. This raises the intriguing prospect that bioavailability of native dietary flavonoids may not be as critical of a limiting factor to bioactivity as previously thought.

Membrane expression of thymidine kinase 1 and potential clinical relevance in lung, breast, and colorectal malignancies

Background

Lung, breast, and colorectal malignancies are the leading cause of cancer-related deaths in the world causing over 2.8 million cancer-related deaths yearly. Despite efforts to improve prevention methods, early detection, and treatments, survival rates for advanced stage lung, breast, and colon cancer remain low, indicating a critical need to identify cancer-specific biomarkers for early detection and treatment. Thymidine kinase 1 (TK1) is a nucleotide salvage pathway enzyme involved in cellular proliferation and considered an important tumor proliferation biomarker in the serum. In this study, we further characterized TK1’s potential as a tumor biomarker and immunotherapeutic target and clinical relevance.

Methods

We assessed TK1 surface localization by flow cytometry and confocal microscopy in lung (NCI-H460, A549), breast (MDA-MB-231, MCF7), and colorectal (HT-29, SW620) cancer cell lines. We also isolated cell surface proteins from HT-29 cells and performed a western blot confirming the presence of TK1 on cell membrane protein fractions. To evaluate TK1’s clinical relevance, we compared TK1 expression levels in normal and malignant tissue through flow cytometry and immunohistochemistry. We also analyzed RNA-Seq data from The Cancer Genome Atlas (TCGA) to assess differential expression of the TK1 gene in lung, breast, and colorectal cancer patients.

Results

We found significant expression of TK1 on the surface of NCI-H460, A549, MDA-MB-231, MCF7, and HT-29 cell lines and a strong association between TK1’s localization with the membrane through confocal microscopy and Western blot. We found negligible TK1 surface expression in normal healthy tissue and significantly higher TK1 expression in malignant tissues. Patient data from TCGA revealed that the TK1 gene expression is upregulated in cancer patients compared to normal healthy patients.

Conclusions

Our results show that TK1 localizes on the surface of lung, breast, and colorectal cell lines and is upregulated in malignant tissues and patients compared to healthy tissues and patients. We conclude that TK1 is a potential clinical biomarker for the treatment of lung, breast, and colorectal cancer.

Electronic supplementary material

The online version of this article (10.1186/s12935-018-0633-9) contains supplementary material, which is available to authorized users.

Meal-derived glucagon responses are related to lower hepatic phosphate concentrations in obesity and type 2 diabetes

AIM

Type 2 diabetes (T2D) alters glucagon, glucagon-like peptide (GLP)-1, glucose-dependent insulinotropic polypeptide (GIP) and hepatic energy metabolism, yet the possible relationships remain unclear.

METHODS

In this observational study, lean insulin-sensitive control subjects (BMI: 23.2±1.5kg/m²), age-matched insulin-resistant obese subjects (BMI: 34.3±1.7kg/m²) and similarly obese elderly T2D patients (BMI: 32.0±2.4kg/m²) underwent mixed-meal tolerance tests (MMTTs), and assessment of hepatic γATP, inorganic phosphate (P_i) and lipids using ³¹P/¹H magnetic resonance spectroscopy. Meal-induced secretion of glucagon and incretins was calculated from incremental areas under the concentration-time curves (iAUCs). Peripheral and adipose tissue insulin sensitivity were assessed from time courses of circulating glucose, insulin and free fatty acids.

RESULTS

MMTT-derived peripheral insulin sensitivity was lowest in T2D patients (P<0.001), while glucagon concentrations were comparable across all three groups. At 260min, GLP-1 was lower in T2D patients than in controls, whereas GIP was lowest in obese individuals. Fasting glucagon concentrations correlated positively with fasting (r=0.60) and postprandial hepatocellular lipid levels (160min: r=0.51, 240min: r=0.59), and negatively with adipose tissue insulin sensitivity (r=-0.73). Higher meal-induced glucagon release (iAUC_0-260min) correlated with lower fasting (r=-0.62) and postprandial P_i levels (160min: r=-0.43, 240min: r=-0.42; all P<0.05). Higher meal-induced release of GIP (iAUC_0-260min) correlated positively with fasting (r=0.54) and postprandial serum triglyceride concentrations (iAUC_0-260min, r=0.54; all P<0.01).

CONCLUSION

Correlations between fasting glucagon and hepatic lipids and between meal-induced glucagon and hepatic P_i suggest a role for glucagon in hepatic energy metabolism.

CD5 expression influences T cell metabolism and mice behavior

T cells are key players in the adaptive immune response and undergo metabolic changes upon activation. CD5 is a co-receptor found on T cells and plays a significant role in regulating T cell thymic development, intracellular signaling and cytokine production. Previous studies have found that naïve T cells with high CD5 expression (CD5hi) have increased TCR signal strength and enhances immune response to foreign peptide in the periphery. Additionally, we have reported that CD5hi naïve T cells have higher calcium mobilization and improved T cell activation compared to CD5lo T cells. Calcium influx levels can modulate and influence metabolic changes in T cells. Thus, we hypothesized that CD5hi, CD5lo and CD5 deficient T cells have different bioenergetic demands that affect metabolic pathways and T cell activation. We evaluated the effects of CD5 levels on metabolism using CD5 deficient mice vs wild type controls and found CD5 deficient T cells had significant differences in metabolic function. Recently published work has described a connection between increased T cell metabolism and altered cognitive function in PD-1 deficient mice. We have also found significant differences between CD5 deficient and wild type mice in marble burying rates, elevated plus and water maze behavior and open field activity. These behavioral test results suggest CD5 deficient mice have altered cognitive function and higher levels of anxiety. Thus, CD5 deficiency alters T cell metabolic and cognitive function.

T Cell Calcium Signaling Regulation by the Co-Receptor CD5

Calcium influx is critical for T cell effector function and fate. T cells are activated when T cell receptors (TCRs) engage peptides presented by antigen-presenting cells (APC), causing an increase of intracellular calcium (Ca2+) concentration. Co-receptors stabilize interactions between the TCR and its ligand, the peptide-major histocompatibility complex (pMHC), and enhance Ca2+ signaling and T cell activation. Conversely, some co-receptors can dampen Ca2+ signaling and inhibit T cell activation. Immune checkpoint therapies block inhibitory co-receptors, such as cytotoxic T-lymphocyte associated antigen 4 (CTLA-4) and programmed death 1 (PD-1), to increase T cell Ca2+ signaling and promote T cell survival. Similar to CTLA-4 and PD-1, the co-receptor CD5 has been known to act as a negative regulator of T cell activation and to alter Ca2+ signaling and T cell function. Though much is known about the role of CD5 in B cells, recent research has expanded our understanding of CD5 function in T cells. Here we review these recent findings and discuss how our improved understanding of CD5 Ca2+ signaling regulation could be useful for basic and clinical research.

Personal microbiome analysis improves student engagement and interest in Immunology, Molecular Biology, and Genomics undergraduate courses

A critical area of emphasis for science educators is the identification of effective means of teaching and engaging undergraduate students. Personal microbiome analysis is a means of identifying the microbial communities found on or in our body. We hypothesized the use of personal microbiome analysis in the classroom could improve science education by making courses more applied and engaging for undergraduate students. We determined to test this prediction in three Brigham Young University undergraduate courses: Immunology, Advanced Molecular Biology Laboratory, and Genomics. These three courses have a two-week microbiome unit and students during the 2016 semester students could submit their own personal microbiome kit or use the demo data, whereas during the 2017 semester students were given access to microbiome data from an anonymous individual. The students were surveyed before, during, and after the human microbiome unit to determine whether analyzing their own personal microbiome data, compared to analyzing demo microbiome data, impacted student engagement and interest. We found that personal microbiome analysis significantly enhanced the engagement and interest of students while completing microbiome assignments, the self-reported time students spent researching the microbiome during the two week microbiome unit, and the attitudes of students regarding the course overall. Thus, we found that integrating personal microbiome analysis in the classroom was a powerful means of improving student engagement and interest in undergraduate science courses.

Prevalence of house dust mite allergens in low-income homes with evaporative coolers in a semiarid climate

House dust mites are typically absent in homes in arid and semiarid climates due to low humidity. Evaporative "swamp" cooling significantly increases indoor humidity in dry climates and is suspected of promoting dust mite survival in these regions. We investigated the prevalence and concentration of mite allergens in dust from low-income homes (N = 22) with evaporative coolers in Utah County, Utah. Overall, 15 homes (68.2%) were positive for either Der p 1 or Der f 1 in at least 1 location. Geometric mean allergen levels in mattresses were 0.107 and 0.087 ug/g dust for Der p 1 and Der f 1, respectively. In furniture, levels were 0.143 and 0.165 ug/g dust for Der p1 and Der f 1, respectively. The percentage of positive homes in this study was much higher than previously reported in larger homes with swamp coolers in the same community. These results suggest socioeconomic factors may play a role in dust mite allergen prevalence in homes with evaporative coolers in dry climates.

Using Backward Design in Education Research: A Research Methods Essay

Education research within the STEM disciplines applies a scholarly approach to teaching and learning, with the intent of better understanding how people learn and of improving pedagogy at the undergraduate level. Most of the professionals practicing in this field have 'crossed over' from other disciplinary fields and thus have faced challenges in becoming experts in a new discipline. In this article, we offer a novel framework for approaching education research design called Backward Design in Education Research. It is patterned on backward curricular design and provides a three-step, systematic approach to designing education projects: 1) Define a research question that leads to a testable causal hypothesis based on a theoretical rationale; 2) Choose or design the assessment instruments to test the research hypothesis; and 3) Develop an experimental protocol that will be effective in testing the research hypothesis. This approach provides a systematic method to develop and carry out evidence-based research design.

Biomarker analysis and clinical relevance of TK1 on the cell membrane of Burkitt's lymphoma and acute lymphoblastic leukemia

TK1 is an enzyme involved in DNA synthesis and repair. TK1 is usually found elevated in cancer patients’ serum, which makes it a useful tumor proliferation biomarker that strongly correlates with cancer stage, metastatic capabilities, and recurrence risk. In this study, we show that TK1 is upregulated and localizes on the plasma membrane of Burkitt’s lymphoma, acute promyelocytic leukemia, T cell leukemia, and acute lymphoblastic leukemia (ALL). Using flow cytometry, we confirmed that TK1 localizes on the surface of Raji, HL60, and Jurkat cell lines and on ALL clinical samples. Using fluorescent microscopy, we found a strong association of TK1 with the plasma membrane in Raji, HL60, and Jurkat cell lines. These findings were also confirmed by scanning electron microscopy. Our study also shows that this phenomenon does not occur on normal resting or proliferating lymphocytes. In addition, we show that membrane TK1 is found in all oligomeric forms ranging from monomer to tetramer and exhibits enzymatic activity. These findings suggest TK1 as a possible target for immunotherapy with the potential to be utilized in the treatment of hematological cancers.

Differential effects of air conditioning type on residential endotoxin levels in a semi-arid climate

Residential endotoxin exposure is associated with protective and pathogenic health outcomes. Evaporative coolers, an energy-efficient type of air conditioner used in dry climates, are a potential source of indoor endotoxins; however, this association is largely unstudied. We collected settled dust biannually from four locations in homes with evaporative coolers (n=18) and central air conditioners (n=22) in Utah County, Utah (USA), during winter (Jan-Apr) and summer (Aug-Sept), 2014. Dust samples (n=281) were analyzed by the Limulus amebocyte lysate test. Housing factors were measured by survey, and indoor temperature and relative humidity measures were collected during both seasons. Endotoxin concentrations (EU/mg) were significantly higher in homes with evaporative coolers from mattress and bedroom floor samples during both seasons. Endotoxin surface loads (EU/m² ) were significantly higher in homes with evaporative coolers from mattress and bedroom floor samples during both seasons and in upholstered furniture during winter. For the nine significant season-by-location comparisons, EU/mg and EU/m² were approximately three to six times greater in homes using evaporative coolers. A plausible explanation for these findings is that evaporative coolers serve as a reservoir and distribution system for Gram-negative bacteria or their cell wall components in homes.

Naïve helper T cells with high CD5 expression have increased calcium signaling

The adaptive immune response is orchestrated by T helper cells and their function is dependent upon interactions between the T cell receptor (TCR), peptide MHC (pMHC) and co-receptors. TCR-pMHC interactions initiate calcium signaling cascades which determine T cell activation, survival, proliferation and differentiation. CD5 is a co-receptor that plays an important role in regulating T cell signaling and fate during thymocyte education. CD5 surface expression on mature single positive thymocytes correlates with the TCR signal strength for positive selecting self-ligands. CD5 also plays a role in T cell function after thymic development is complete. Peripheral T cells with higher CD5 expression respond better to foreign antigen than those with lower CD5 expression and CD5-high T cells are enriched in memory populations. In our study, we examined the role of CD5 expression and calcium signaling in the primary response of T cells using two Listeria monocytogenes specific T helper cells (LLO118 and LLO56). These T cells recognize the same immunodominant epitope (LLO_190-205) of L. monocytogenes and have divergent primary and secondary responses and different levels of CD5 expression. We found that each T cell has unique calcium mobilization in response to in vitro stimulation with LLO_190-205 and that CD5 expression levels in these cells changed over time following stimulation. LLO56 naïve T helper cells, which expresses higher levels of CD5, have higher calcium mobilization than naïve LLO118 T cells. Three days after in vitro stimulation, LLO118 T cells had more robust calcium mobilization than LLO56 and there were no differences in calcium mobilization 8 days after in vitro stimulation. To further evaluate the role of CD5, we measured calcium signaling in CD5 knockout LLO118 and LLO56 T cells at these three time points and found that CD5 plays a significant role in promoting the calcium signaling of naïve CD5-high LLO56 T cells.

Method to Increase Undergraduate Laboratory Student Confidence in Performing Independent Research

The goal of an undergraduate laboratory course should be not only to introduce the students to biology methodologies and techniques, but also to teach them independent analytical thinking skills and proper experiment design. This is especially true for advanced biology laboratory courses that undergraduate students typically take as a junior or senior in college. Many courses achieve the goal of teaching techniques, but fail to approach the larger goal of teaching critical thinking, experimental design, and student independence. Here we describe a study examining the application of the scaffolding instructional philosophy in which students are taught molecular techniques with decreasing guidance to force the development of analytical thinking skills and prepare undergraduate students for independent laboratory research. This method was applied to our advanced molecular biology laboratory class and resulted in an increase of confidence among the undergraduate students in their abilities to perform independent research.

Non-small-cell lung cancer cell lines A549 and NCI-H460 express hypoxanthine guanine phosphoribosyltransferase on the plasma membrane

In both males and females, lung cancer is one of the most lethal cancers worldwide and accounts for >30% of cancer-related deaths. Despite advances in biomarker analysis and tumor characterization, there remains a need to find suitable biomarker antigen targets for treatment in late-stage lung cancer. Previous research on the salvage pathway enzyme TK1 shows a unique relationship with cancer patients as serum levels are raised according to cancer grade. To expand this analysis, the other salvage pathway enzymes were evaluated for possible upregulation within lung cancer. Adenine phosphoribosyltransferase, deoxycytidine kinase, and hypoxanthine guanine phosphoribosyltransferase (HPRT) were assessed for their presentation on two non-small-cell lung cancer cell lines NCI-H460 and A549. In the present study, we show that deoxycytidine kinase and adenine phosphoribosyltransferase have no significant relationship with the membrane of NCI-H460 cells. However, we found significant localization of HPRT to the membrane of NCI-H460 and A549 cells. When treated with anti-HPRT antibodies, the average fluorescence of the cell population increased by 24.3% and 12.9% in NCI-H460 and A549 cells, respectively, in comparison with controls. To ensure that expression was not attributed to cytoplasmic HPRT, confocal microscopy was performed to visualize HPRT binding on the plasma membrane. After staining NCI-H460 cells treated with both fluorescent antibodies and a membrane-specific dye, we observed direct overlap between HPRT and the membrane of the cancer cells. Additionally, gold-conjugated antibodies were used to label and quantify the amount of HPRT on the cell surface using scanning electron microscopy and energy-dispersive analysis X-ray. Further confirming HPRT presence, the gold weight percentage of the sample increased significantly when NCI-H460 cells were exposed to HPRT antibody (P=0.012) in comparison with isotype controls. Our results show that HPRT is localized on the surface of these non-small-cell lung cancer cell lines.

Circulating adiponectin concentration is inversely associated with glucose tolerance and insulin secretion in people with newly diagnosed diabetes

AIMS

To examine the hypothesis that changes in serum adiponectin concentration inversely relate to changes in glucose tolerance and β-cell function already during the early stage of disease progression in recently diagnosed Type 1 and Type 2 diabetes mellitus.

METHODS

Participants in the prospective observational German Diabetes Study (Type 2 diabetes, n = 94; Type 1 diabetes, n = 42) underwent i.v. glucose tolerance and glucagon stimulation testing to assess pre-hepatic β-cell function, glucose tolerance index and C-peptide secretion within the first year of diabetes diagnosis and 2 years later. Associations of changes in serum concentrations of total adiponectin, high-molecular-weight adiponectin and their ratio with changes in the aforementioned metabolic variables were calculated using linear regression.

RESULTS

Among people with Type 2 diabetes, 2-year increases in high-molecular-weight adiponectin and in high-molecular-weight/total adiponectin ratio were associated with decreases in glucose tolerance index of 0.1%/min (P = 0.020) and 0.8%/min (P = 0.013), respectively. Increases in high-molecular-weight/total adiponectin ratio were related to decreases in acute C-peptide secretion of 54.6% (P = 0.020). Among people with Type 1 diabetes, 2-year increases in total adiponectin were associated with 2-year decreases in acute C-peptide secretion of 56.2% (P = 0.035).

CONCLUSIONS

Increases in adiponectin concentrations in the first 2 years after diagnosis were related to a worsening of acute insulin secretion and glucose tolerance index in Type 1 and Type 2 diabetes. (Clinical Trials Registry no.: NCT01055093).

Do dogs sense hypoglycaemia?

AIMS

To summarize the current knowledge on the phenomenon of dogs, both trained and untrained, sensing hypoglycaemia and alerting their owners to it.

METHODS

Electronic databases were searched for all types of articles reporting on untrained or trained 'diabetes alert' dogs. Articles published up until December 2014 in the English or German language were included.

RESULTS

Several case reports and observational studies provide evidence that animals can perform at a level above that attributable to chance, and may reliably detect low diurnal as well as nocturnal hypoglycaemic episodes. Behavioural changes in untrained dogs were reported during 38-100% of hypoglycaemic events experienced by their owners. The sensitivity and specificity of the performance of trained diabetes alert dogs sensing hypoglycaemia ranged from 22 to 100% and 71 to 90%, respectively. Additionally, 75-81% of patients with diabetes who owned a trained dog reported a subsequent improvement in their quality of life. Nevertheless, the available data are limited and heterogeneous because they rely on low patient numbers and survey-based studies prone to recall bias.

CONCLUSION

Further research is needed to confirm the preliminary data on the reliability and mechanism underlying the dogs' abilities to detect hypoglycaemia, and its impact on patient outcomes.

The Impact of Dietary Factors on Glycemic Control, Insulin Sensitivity and Secretion in the First Years after Diagnosis of Diabetes

BACKGROUND

Dietary factors play an important role in the prevention of diabetes mellitus. We tested the hypothesis that dietary factors related to diabetes onset also associate with its progression, i. e., early time courses of insulin sensitivity and secretion in both type 1 and type 2 diabetes.

METHODS

In a prospective observational study, well-controlled recent-onset diabetes patients (n=127) underwent detailed metabolic characterization within the first year after diagnosis. A follow-up was conducted 2 years after the first examination. Insulin secretion and sensitivity were assessed by intravenous glucose tolerance testing. Baseline food consumption was analyzed by a food propensity questionnaire. Multivariate linear regression analysis was used to assess associations between consumption frequencies at baseline with metabolic changes during the first 2 years.

RESULTS

Within the first 2 years, metabolic control did not change in patients with type 1 and type 2 diabetes on average. In type 1 diabetes, an increased consumption frequency of refined grains by one time/day at baseline associated with higher HbA1c by 0.60% (95% CI: 0.04; 1.16), P=0.04 after 2 years compared to baseline. In type 2 diabetes, an increased consumption frequency of meat/meat products by one time/day at baseline associated with lower beta-cell adaptation index (-7.25% (95% CI: -13.16; -0.93), P=0.03) after adjustment for age, sex, BMI, and changes of BMI and glucose-lowering medication.

CONCLUSION

Dietary factors associate with the initial course of diabetes. Reduced consumption of refined grains in type 1 diabetes and of meat products in type 2 diabetes may contribute to preservation of insulin secretion and sensitivity.

Evaporative Cooler Use Influences Temporal Indoor Relative Humidity but Not Dust Mite Allergen Levels in Homes in a Semi-Arid Climate

Concerns about energy consumption and climate change make residential evaporative coolers a popular alternative to central air conditioning in arid and semi-arid climates. However, evaporative coolers have been shown to significantly increase indoor relative humidity and dust mite allergen levels in some studies, while showing no association in other studies. Improved measurement of temporal fluctuations in indoor relative humidity may help identify factors that promote mite growth in homes in dry climates. Dust samples and continuous indoor relative humidity measurements were collected from homes with central air conditioning and homes with evaporative coolers in Utah. Samples were collected over two seasons, winter/spring (Jan–Apr) and summer (July–Sept), 2014. Dust samples were analyzed for Der p 1 and Der f 1 using a two-site monoclonal antibody-based enzyme-linked immunosorbent assay (ELISA) analysis. Housing characteristics including age of home, occupant density, and age of mattresses, furniture, and carpeting were also measured. Positive Der p 1 or Der f 1 samples were found in 25.0% of the homes and there was no difference in mean allergen levels by type of air conditioning. Indoor relative humidity was significantly higher in homes with evaporative coolers compared to those with central air conditioning during the summer. Homes with evaporative coolers also spent significantly more time during summer above 55.0% and 65.0% relative humidity compared to central air homes, but not above 75.0%. Findings from this study suggest that increased humidity from evaporative coolers may not be sufficient to exceed the critical equilibrium humidity or maintain humidity excursions for sufficient duration in relatively larger single-family homes in semi-arid climates to support mite growth and reproduction.

Pharmacologic immunosuppression of mononuclear phagocyte phagocytosis by caffeine

Caffeine is the most widely used neurostimulant in the world. There is considerable debate on its effect on immune cells as it has been shown to antagonize adenosine receptors (ARs), which mediate an anti-inflammatory switch in activated immune cells. A second target is phosphodiesterase, where it acts as an inhibitor. If the primary effect of caffeine on mononuclear phagocytes were to antagonize ARs we would expect cells exposed to caffeine to have a prolonged proinflammatory response. The aim of this study was to investigate the effects and mechanism of action of caffeine in mononuclear phagocytes. Human mononuclear phagocytes were separated from whole blood and pretreated with protein kinase A inhibitor (PKA) and then exposed to micromolar physiological concentrations of caffeine. Phagocytosis and phagocytosis exhaustion were quantified using flow cytometry. Treatments were analyzed and compared to controls, using a beta regression controlling for factors of age, gender, caffeine intake, and exercise. We found that caffeine suppresses phagocytosis at micromolar physiological concentrations. This suppression was prevented when mononuclear phagocytes were pretreated with PKA inhibitor, suggesting that caffeine's phagocytic suppression may be due to its function as a phosphodiesterase inhibitor, pushing cells towards an anti-inflammatory response. Additionally, these effects are altered by regular caffeine intake and fitness level, emphasizing that tolerance and immune robustness are important factors in mononuclear phagocyte activation. These results demonstrate that caffeine may be acting as a phosphodiesterase inhibitor and suppressing phagocytosis in mononuclear phagocytes by promoting an anti-inflammatory response.

Anticipation of Personal Genomics Data Enhances Interest and Learning Environment in Genomics and Molecular Biology Undergraduate Courses

An important discussion at colleges is centered on determining more effective models for teaching undergraduates. As personalized genomics has become more common, we hypothesized it could be a valuable tool to make science education more hands on, personal, and engaging for college undergraduates. We hypothesized that providing students with personal genome testing kits would enhance the learning experience of students in two undergraduate courses at Brigham Young University: Advanced Molecular Biology and Genomics. These courses have an emphasis on personal genomics the last two weeks of the semester. Students taking these courses were given the option to receive personal genomics kits in 2014, whereas in 2015 they were not. Students sent their personal genomics samples in on their own and received the data after the course ended. We surveyed students in these courses before and after the two-week emphasis on personal genomics to collect data on whether anticipation of obtaining their own personal genomic data impacted undergraduate student learning. We also tested to see if specific personal genomic assignments improved the learning experience by analyzing the data from the undergraduate students who completed both the pre- and post-course surveys. Anticipation of personal genomic data significantly enhanced student interest and the learning environment based on the time students spent researching personal genomic material and their self-reported attitudes compared to those who did not anticipate getting their own data. Personal genomics homework assignments significantly enhanced the undergraduate student interest and learning based on the same criteria and a personal genomics quiz. We found that for the undergraduate students in both molecular biology and genomics courses, incorporation of personal genomic testing can be an effective educational tool in undergraduate science education.

Type 1 diabetes mellitus and exercise in competitive athletes

AIMS

The number of patients with type 1 diabetes mellitus who are actively participating in competitive sports is increasing. Here, we aimed to assess individual experiences of competitive athletes with type 1 diabetes and to compare these experiences with current recommendations.

METHODS

A survey of 20 competitive athletes with type 1 diabetes, categorized as endurance (n=10) and non-endurance (n=10) athletes, was performed.

RESULTS

Endurance and non-endurance athletes did not differ in gender distribution, age, body mass index, and known diabetes duration. Self-reported target blood glucose values prior to exercise were lower in non-endurance than in endurance athletes (195±34 vs. 137±28 mg/dl, P=0.001). The majority of all athletes experienced activity-induced hypo- and hyperglycemic events, independently of exercise type. However, endurance athletes used additional carbohydrate units to prevent activity-induced hypoglycemic events more frequently without monitoring their blood glucose levels than non-endurance athletes (50% vs. 0%, P=0.01). The reduction of the insulin dose on training and competition days compared to days without exercise was similar for endurance and non-endurance athletes.

CONCLUSION

These results point to a very individual adaption of the athlete's therapy during training and competition. However, there are distinct differences in diabetes management between endurance and non-endurance athletes.

Dynamics of CD4(+) T cell responses against Listeria monocytogenes

The generation of CD4(+) T cell memory cells is poorly understood. Recently, two different murine CD4(+) TCR transgenic T cell lines, LLO118 and LLO56, both specific for the same epitope but differing in their expression level of the cell surface protein CD5, were generated. Notably, these cell lines showed different behavior upon primary and secondary exposure to Listeria monocytogenes. Whereas LLO118 showed a stronger primary response and generated more robust CD8(+) T cell help upon secondary exposure, LLO56 CD4(+) T cells had a dramatically better recall response. Using different mathematical models, we analyzed the dynamics of the two CD4(+) T cell lines in mice during infection with L. monocytogenes. Our models allowed the quantitative comparison of the two T cell lines and provided predictions for the conversion of naive T cells into memory cells. LLO118 CD4(+) T cells are estimated to have a higher proliferation rate than LLO56 CD4(+) T cells upon primary exposure. This difference can be explained by the lower expression level of CD5 on LLO118 CD4(+) T cells. Furthermore, LLO56 memory cells are predicted to have a 3-fold longer half-life than LLO118 memory cells ($${t}_{1/2}^{\hbox{ LLO }118}$$ ≈ 4.3 to 5 d and $${t}_{1/2}^{\hbox{ LLO }56}$$ ≈ 11.5 to 13.9 d). Although both cell lines differ in their memory capabilities, our analysis indicates no difference in the rate at which memory cells are generated. Our results show that different CD5 expression levels influence the proliferation dynamics of activated naive CD4(+) T cells while leaving the conversion rate of those cells into memory cells unaffected.

Subtle changes in TCRα CDR1 profoundly increase the sensitivity of CD4 T cells

Changes in the peptide and MHC molecules have been extensively examined for how they alter T cell activation, but many fewer studies have examined the TCR. Structural studies of how TCR differences alter T cell specificity have focused on broad variation in the CDR3 loops. However, changes in the CDR1 and 2 loops can also alter TCR recognition of pMHC. In this study we focus on two mutations in the CDR1α loop of the TCR that increased the affinity of a TCR for agonist Hb(64-76)/I-E(k) by increasing the on-rate of the reaction. These same mutations also conferred broader recognition of altered peptide ligands. TCR transgenic mice expressing the CDR1α mutations had altered thymic selection, as most of the T cells were negatively selected compared to T cells expressing the wildtype TCR. The few T cells that escaped negative selection and were found in the periphery were rendered anergic, thereby avoiding autoimmunity. T cells with the CDR1α mutations were completely deleted in the presence of Hb(64-76) as an endogenous peptide. Interestingly, the wildtype T cells were not eliminated, identifying a threshold affinity for negative selection where a 3-fold increase in affinity is the difference between incomplete and complete deletion. Overall, these studies highlight how small changes in the TCR can increase the affinity of TCR:pMHC but with the consequences of skewing selection and producing an unresponsive T cell.