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1.
Front Immunol ; 14: 1290688, 2023.
Article in English | MEDLINE | ID: mdl-38124752

ABSTRACT

Pathogens escape host defenses by T-cell epitope mutation or deletion (immune escape) and by simulating the appearance of human T cell epitopes (immune camouflage). We identified a highly conserved, human-like T cell epitope in non-structural protein 7 (NSP7) of SARS-CoV-2, RNA-dependent RNA polymerase (RdRp) hetero-tetramer complex. Remarkably, this T cell epitope has significant homology to a T regulatory cell epitope (Tregitope) previously identified in the Fc region of human immunoglobulin G (IgG) (Tregitope 289). We hypothesized that the SARS-CoV-2 NSP7 epitope (NSP7-289) may induce suppressive responses by engaging and activating pre-existing regulatory T cells. We therefore compared NSP7-289 and IgG Tregitopes (289 and 289z, a shorter version of 289 that isolates the shared NSP7 epitope) in vitro. Tregitope peptides 289, 289z and NSP7-289 bound to multiple HLA-DRB1 alleles in vitro and suppressed CD4+ and CD8+ T cell memory responses. Identification and in vitro validation of SARS-CoV-2 NSP7-289 provides further evidence of immune camouflage and suggests that pathogens can use human-like epitopes to evade immune response and potentially enhance host tolerance. Further exploration of the role of cross-conserved Tregs in human immune responses to pathogens such as SARS-CoV-2 is warranted.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , T-Lymphocytes, Regulatory , Epitopes, T-Lymphocyte , COVID-19/metabolism , CD8-Positive T-Lymphocytes , Immunoglobulin G
2.
J Infect Public Health ; 15(10): 1118-1123, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36137361

ABSTRACT

BACKGROUND: Nosocomial acquisition of influenza is known to occur but the risk after exposure to a known case and the outcomes after acquisition are poorly defined. METHODS: Prospective observational study of patients exposed to influenza from another patient in a multi-site healthcare organisation, with follow-up of 7 days or until discharge, and PCR-confirmation of symptomatic disease. Multivariable analysis was used to investigate association of influenza acquisition with high dependency unit/intensive care unit (HDU/ITU) admission and in-hospital mortality. RESULTS: 23/298 (7.7%) contacts of 11 cases were subsequently symptomatic and tested influenza-positive during follow-up. HDU/ITU admission was significantly higher in these secondary cases (6/23, 26%) compared to flu-negative contacts (20/275, 7.2%; p = 0.002). In-hospital mortality was significantly higher in secondary cases (5/23, 21.7%) compared to flu-negative contacts (11/275, 4%; p < 0.001). In multivariable analysis, age (OR 1.25 95% CI: 1.01-1.54, p = 0.02) and being a secondary case (OR 4.77, 95% CI: 1.63-13.9, p = 0.008) were significantly associated with HDU/ITU admission in contacts. Age (OR 1.00, 95% CI: 0.93-1.00, p = 0.02), being a secondary case after exposure to influenza (OR 3.81, 95% CI 1.09-13.3, p = 0.049) and co-morbidity (OR 1.29 per unit increment in the Charlson score, 95% CI 1.02-1.61, p = 0.03) were significantly associated with in-hospital mortality in contacts. CONCLUSIONS: Nosocomial acquisition of influenza was significantly associated with increased risk of HDU/ITU admission and in-hospital mortality.


Subject(s)
Cross Infection , Influenza, Human , Humans , Influenza, Human/complications , Influenza, Human/epidemiology , Cross Infection/epidemiology , Hospitalization , Prospective Studies , Intensive Care Units , Morbidity
3.
Front Immunol ; 12: 636731, 2021.
Article in English | MEDLINE | ID: mdl-34220802

ABSTRACT

Infantile-onset Pompe disease (IOPD) is a glycogen storage disease caused by a deficiency of acid alpha-glucosidase (GAA). Treatment with recombinant human GAA (rhGAA, alglucosidase alfa) enzyme replacement therapy (ERT) significantly improves clinical outcomes; however, many IOPD children treated with rhGAA develop anti-drug antibodies (ADA) that render the therapy ineffective. Antibodies to rhGAA are driven by T cell responses to sequences in rhGAA that differ from the individuals' native GAA (nGAA). The goal of this study was to develop a tool for personalized immunogenicity risk assessment (PIMA) that quantifies T cell epitopes that differ between nGAA and rhGAA using information about an individual's native GAA gene and their HLA DR haplotype, and to use this information to predict the risk of developing ADA. Four versions of PIMA have been developed. They use EpiMatrix, a computational tool for T cell epitope identification, combined with an HLA-restricted epitope-specific scoring feature (iTEM), to assess ADA risk. One version of PIMA also integrates JanusMatrix, a Treg epitope prediction tool to identify putative immunomodulatory (regulatory) T cell epitopes in self-proteins. Using the JanusMatrix-adjusted version of PIMA in a logistic regression model with data from 48 cross-reactive immunological material (CRIM)-positive IOPD subjects, those with scores greater than 10 were 4-fold more likely to develop ADA (p<0.03) than those that had scores less than 10. We also confirmed the hypothesis that some GAA epitopes are immunomodulatory. Twenty-one epitopes were tested, of which four were determined to have an immunomodulatory effect on T effector response in vitro. The implementation of PIMA V3J on a secure-access website would allow clinicians to input the individual HLA DR haplotype of their IOPD patient and the GAA pathogenic variants associated with each GAA allele to calculate the patient's relative risk of developing ADA, enhancing clinical decision-making prior to initiating treatment with ERT. A better understanding of immunogenicity risk will allow the implementation of targeted immunomodulatory approaches in ERT-naïve settings, especially in CRIM-positive patients, which may in turn improve the overall clinical outcomes by minimizing the development of ADA. The PIMA approach may also be useful for other types of enzyme or factor replacement therapies.


Subject(s)
Computational Biology/methods , Glycogen Storage Disease Type II/immunology , T-Lymphocyte Subsets/immunology , T-Lymphocytes, Regulatory/immunology , alpha-Glucosidases/metabolism , Enzyme Replacement Therapy , Epitope Mapping , Female , HLA-DR Antigens/genetics , Humans , Immune Tolerance , Infant , Male , Precision Medicine , Prognosis , Regression Analysis , Risk , alpha-Glucosidases/genetics , alpha-Glucosidases/immunology
4.
Front Immunol ; 12: 634509, 2021.
Article in English | MEDLINE | ID: mdl-33953711

ABSTRACT

Tregitopes (T regulatory epitopes) are IgG-derived peptides with high affinity to major histocompatibility complex class II (MHCII), that are known to promote tolerance by activating T regulatory cell (Treg) activity. Here we characterized the effect of IgG Tregitopes in a well-established murine model of allergic asthma, demonstrating in vivo antigen-specific tolerance via adoptive transfer of Tregitope-and-allergen-activated Tregs. Asthma is a heterogeneous chronic inflammatory condition affecting the airways and impacting over 300 million individuals worldwide. Treatment is suppressive, and no current therapy addresses immune regulation in severely affected asthmatics. Although high dose intra-venous immunoglobulin (IVIg) is not commonly used in the asthma clinic setting, it has been shown to improve severe asthma in children and in adults. In our laboratory, we previously demonstrated that IVIg abrogates airway hyperresponsiveness (AHR) in a murine model of asthma and induces suppressive antigen-specific T-regulatory cells. We hypothesized that IgG-derived Tregitopes would modulate allergic airway disease by inducing highly suppressive antigen-specific Tregs capable of diminishing T effector cell responses and establishing antigen-specific tolerance. Using ovalbumin (OVA-) and ragweed-driven murine models of allergic airway disease, we characterized the immunoregulatory properties of Tregitopes and performed Treg adoptive transfer to OVA- and ragweed-allergic mice to test for allergen specificity. Treatment with Tregitopes attenuated allergen-induced airway hyperresponsiveness and lung inflammation. We demonstrated that Tregitopes induce highly suppressive allergen-specific Tregs. The tolerogenic action of IgG Tregitopes in our model is very similar to that of IVIg, so we foresee that IgG Tregitopes could potentially replace steroid-based treatment and can offer a synthetic alternative to IVIg in a range of inflammatory and allergic conditions.


Subject(s)
Anti-Asthmatic Agents/pharmacology , Asthma/drug therapy , Epitopes, T-Lymphocyte/drug effects , Immunoglobulin Fab Fragments/pharmacology , Immunoglobulin Fc Fragments/pharmacology , Lung/drug effects , Lymphocyte Activation/drug effects , T-Lymphocytes, Regulatory/drug effects , Adoptive Transfer , Animals , Animals, Genetically Modified , Antigens, Plant , Asthma/immunology , Asthma/metabolism , Asthma/physiopathology , Bronchoconstriction/drug effects , Cells, Cultured , Cytokines/metabolism , Disease Models, Animal , Epitopes, T-Lymphocyte/immunology , Epitopes, T-Lymphocyte/metabolism , Humans , Inflammation Mediators/metabolism , Lung/immunology , Lung/metabolism , Lung/physiopathology , Mice, Inbred C57BL , Ovalbumin , Plant Extracts , T-Lymphocytes, Regulatory/immunology , T-Lymphocytes, Regulatory/metabolism , T-Lymphocytes, Regulatory/transplantation
5.
Ann Surg Oncol ; 28(12): 7577-7588, 2021 Nov.
Article in English | MEDLINE | ID: mdl-33974197

ABSTRACT

BACKGROUND: Evidence-based tools are necessary for scientifically improving the way MTBs work. Such tools are available but can be difficult to use. This study aimed to develop a robust observational assessment tool for use on cancer multidisciplinary tumor boards (MTBs) by health care professionals in everyday practice. METHODS: A retrospective cross-sectional observational study was conducted in the United Kingdom from September 2015 to July 2016. Three tumor boards from three teaching hospitals were recruited, with 44 members overall. Six weekly meetings involving 146 consecutive cases were video-recorded and scored using the validated MODe tool. Data were subjected to reliability and validity analysis in the current study to develop a shorter version of the MODe. RESULTS: Phase 1, a reduction of the original items in the MODe, was achieved through two focus group meetings with expert assessors based on previous research. The 12 original items were reduced to 6 domains, receiving full agreement by the assessors. In phase 2, the six domains were subjected to item reliability, convergent validation, and internal consistency testing against the MODe-Lite global score, the MODe global score, and the items of the MODe. Significant positive correlations were evident across all domains (p < 0.01), indicating good reliability and validity. In phase 3, feasibility and high inter-assessor reliability were achieved by two clinical assessors. Six domains measuring clinical input, holistic input, clinical collaboration, pathology, radiology, and management plan were integrated into MODe-Lite. CONCLUSIONS: As an evidence-based tool for health care professionals in everyday practice, MODe-Lite gives cancer MTBs insight into the way they work and facilitates improvements in practice.


Subject(s)
Neoplasms , Cross-Sectional Studies , Humans , Neoplasms/therapy , Psychometrics , Reproducibility of Results , Retrospective Studies , Surveys and Questionnaires , United Kingdom
7.
Mymensingh Med J ; 30(2): 559-561, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33830143

ABSTRACT

Hepatitis A virus (HAV) is the most common cause of acute viral hepatitis in the world. Infection with hepatitis A virus can cause severe or even fatal illness in patients with chronic liver disease. Here we present a case which seems to be an isolated acute viral hepatitis A infection at the beginning but later found to be coexisted with Wilson's disease. A 14-year-old girl presented in the Department of Gastroenterology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh on 11th April 2019 with progressive jaundice with prodrome, dark urine, itching, hepatomegaly and thyromegaly. She was found positive for serum IgM HAV antibody. Her jaundice was increasing along with prolonged prothrombin time and low albumin. She had coexisting Wilson's disease evidenced by increased 24 hours urinary copper (138µgm/day). She was treated with D-Penicillamine and Zinc acetate. Hepatitis A can be considered as a factor for acute decompensation in undiagnosed patients with Wilson's disease. So it is very crucial to investigate Wilson's disease in appropriate clinical setting of prolonged jaundice and liver dysfunction.


Subject(s)
Hepatitis A virus , Hepatitis A , Hepatolenticular Degeneration , Jaundice , Adolescent , Bangladesh , Copper , Female , Hepatitis A/complications , Hepatitis A/diagnosis , Hepatolenticular Degeneration/complications , Hepatolenticular Degeneration/diagnosis , Hepatolenticular Degeneration/drug therapy , Humans , Jaundice/diagnosis , Jaundice/etiology , Penicillamine
8.
Clin Immunol ; 224: 108661, 2021 03.
Article in English | MEDLINE | ID: mdl-33412295

ABSTRACT

Identification of T cell epitopes that are recognized by Tregs may elucidate the relative contributions of thymic Tregs and induced Tregs to control of autoimmune diseases and allergy. One such T regulatory cell epitope or 'Tregitope', derived from blood Factor V, is described here. Tregs responding to Tregitope FV621 are potent suppressors of CD4+ T effector responses to Tetanus Toxoid in an in vitro bystander suppression assay, strongly inhibit proliferation of effector CD8+ T cells, down-modulate CD86 and HLA DR on antigen-presenting cells, and enhance expression of granzyme B in Tregs. Tregitope FV621 also suppresses anti-OVA immune responses in vivo. The immunomodulatory effect of Tregitope FV621 is enhanced when conjugated to albumin, suggesting that the short half-life of Tregitope peptides can be prolonged. The in silico tools used to prospectively identify the FV Tregitope described here, when combined with in vitro /in vivo validating assays, may facilitate future Tregitope discoveries.


Subject(s)
CD4-Positive T-Lymphocytes/physiology , CD8-Positive T-Lymphocytes/physiology , Epitopes, T-Lymphocyte/metabolism , Factor V/metabolism , T-Lymphocytes, Regulatory/metabolism , Amino Acid Sequence , Animals , Biomarkers/metabolism , Bystander Effect , Epitopes, T-Lymphocyte/chemistry , Factor V/chemistry , Humans , Immunoglobulin G , Membrane Proteins , Mice , Ovalbumin/immunology , Peptides/chemistry , Tetanus Toxoid
9.
Cell Rep ; 32(1): 107855, 2020 07 07.
Article in English | MEDLINE | ID: mdl-32640221

ABSTRACT

The liver harbors two main innate lymphoid cell (ILC) populations: conventional NK (cNK) cells and tissue-resident NK (trNK) cells. Using the MCMV model of infection, we find that, in contrast to liver cNK cells, trNK cells initially undergo a contraction phase followed by a recovery phase to homeostatic levels. The contraction is MCMV independent because a similar phenotype is observed following poly(I:C)/CpG or α-GalCer injection. The rapid contraction phase is due to apoptosis, whereas the recovery phase occurs via proliferation in situ. Interestingly, trNK cell apoptosis is not mediated by fratricide and not induced by liver lymphocytes or inflammatory cytokines. Instead, we find that trNK cell apoptosis is the consequence of an increased sensitivity to lactic acid. Mechanistic analysis indicates that trNK cell sensitivity to lactate is linked to impaired mitochondrial function. These findings underscore the distinctive properties of the liver-resident NK cell compartment.


Subject(s)
Inflammation/pathology , Killer Cells, Natural/pathology , Lactates/metabolism , Liver/pathology , Animals , Apoptosis , Cell Proliferation , Cellular Microenvironment , Cytokines/metabolism , Herpesviridae Infections/pathology , Herpesviridae Infections/virology , Kinetics , Mice, Inbred C57BL , Muromegalovirus/physiology , Signal Transduction
10.
Sci Adv ; 5(10): eaaw3113, 2019 10.
Article in English | MEDLINE | ID: mdl-31681835

ABSTRACT

The tumor-suppressing function of SMAD4 is frequently subverted during mammary tumorigenesis, leading to cancer growth, invasion, and metastasis. A long-standing concept is that SMAD4 is not regulated by phosphorylation but ubiquitination. Our search for signaling pathways regulated by breast tumor kinase (BRK), a nonreceptor protein tyrosine kinase that is up-regulated in ~80% of invasive ductal breast tumors, led us to find that BRK competitively binds and phosphorylates SMAD4 and regulates transforming growth factor-ß/SMAD4 signaling pathway. A constitutively active BRK (BRK-Y447F) phosphorylates SMAD4, resulting in its recognition by the ubiquitin-proteasome system, which accelerates SMAD4 degradation. Activated BRK-mediated degradation of SMAD4 is associated with the repression of tumor suppressor gene FRK and increased expression of mesenchymal markers, SNAIL, and SLUG. Thus, our data suggest that combination therapies targeting activated BRK signaling may have synergized the benefits in the treatment of SMAD4 repressed cancers.


Subject(s)
Breast Neoplasms/metabolism , Neoplasm Proteins/metabolism , Protein-Tyrosine Kinases/metabolism , Smad4 Protein/metabolism , Snail Family Transcription Factors/metabolism , Breast Neoplasms/pathology , Cell Line, Tumor , Epithelial-Mesenchymal Transition , Female , Gene Expression Regulation, Neoplastic , Genes, Tumor Suppressor , Humans , Neoplasm Proteins/genetics , Phosphorylation , Protein-Tyrosine Kinases/genetics , Smad4 Protein/genetics , Transforming Growth Factor beta/metabolism , Tyrosine/metabolism , Ubiquitination
11.
Nat Commun ; 10(1): 1444, 2019 03 29.
Article in English | MEDLINE | ID: mdl-30926899

ABSTRACT

The phosphatase Shp-2 was implicated in NK cell development and functions due to its interaction with NK inhibitory receptors, but its exact role in NK cells is still unclear. Here we show, using mice conditionally deficient for Shp-2 in the NK lineage, that NK cell development and responsiveness are largely unaffected. Instead, we find that Shp-2 serves mainly to enforce NK cell responses to activation by IL-15 and IL-2. Shp-2-deficient NK cells have reduced proliferation and survival when treated with high dose IL-15 or IL-2. Mechanistically, Shp-2 deficiency hampers acute IL-15 stimulation-induced raise in glycolytic and respiration rates, and causes a dramatic defect in ERK activation. Moreover, inhibition of the ERK and mTOR cascades largely phenocopies the defect observed in the absence of Shp-2. Together, our data reveal a critical function of Shp-2 as a molecular nexus bridging acute IL-15 signaling with downstream metabolic burst and NK cell expansion.


Subject(s)
Extracellular Signal-Regulated MAP Kinases/metabolism , Killer Cells, Natural/metabolism , Protein Tyrosine Phosphatase, Non-Receptor Type 11/metabolism , Receptors, Interleukin-15/metabolism , Animals , Antigens, Ly/metabolism , Cell Count , Cell Proliferation/drug effects , Cell Size/drug effects , Enzyme Activation/drug effects , Integrases/metabolism , Interleukin-15/pharmacology , Killer Cells, Natural/drug effects , Mice, Inbred C57BL , Mice, Knockout , Muromegalovirus/physiology , Natural Cytotoxicity Triggering Receptor 1/metabolism , Protein Tyrosine Phosphatase, Non-Receptor Type 11/deficiency , TOR Serine-Threonine Kinases/metabolism
12.
Ann R Coll Surg Engl ; 101(1): 30-34, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30286648

ABSTRACT

INTRODUCTION: A virtual clinic is a form of telemedicine where contact between clinical teams and patients occur without face-to-face consultation. Our study aims to quantify the clinical, financial and environmental benefits of our virtual urology clinic. MATERIAL AND METHODS: We collected data prospectively from our weekly follow-up virtual clinic over a continuous four-month period between July and September 2017. RESULTS: In total, we reviewed 409 patients. Following virtual clinic consultation, 68.5% of our patients were discharged from further follow-up. The majority of our patients (male 57.7%, female 55.5%) were of working age. The satisfaction scores were high, at 90.1%, and there were no reported adverse events as a result of using the virtual clinic. Our calculated cost savings were £18,744, with a predicted 12-month cost saving of £56,232. The creation of additional face-to-face clinic capacity has created an estimated 12-month increase in tariff generation for our unit of £72,072. In total, 4623 travel miles were avoided by patients using the virtual clinic, with an estimated avoided carbon footprint of 0.35-1.45 metric tonnes of CO2e, depending on mode of transport. Our predicted 12-month avoided carbon footprint is 1.04-4.04 metric tonnes of CO2e. CONCLUSIONS: Our virtual clinic model has demonstrated a trifecta of positive outcomes, namely, clinical, financial and environmental benefits. The environmental importance and benefits of a virtual clinic should be promoted as a social enterprise value when engaging stakeholders in setting up such a urological service. We propose the adoption of our virtual clinic model in those urological units considering this method of telemedicine.


Subject(s)
Health Care Costs , Remote Consultation , Urologic Diseases/diagnosis , Cost Savings , Female , Humans , Male , Middle Aged , Patient Satisfaction , Prospective Studies , Remote Consultation/economics , Remote Consultation/methods , Remote Consultation/organization & administration , Urologic Diseases/therapy
13.
Mol Immunol ; 115: 39-55, 2019 11.
Article in English | MEDLINE | ID: mdl-30482463

ABSTRACT

Interactions between germline-encoded natural killer (NK) cell receptors and their respective ligands on tumorigenic or virus-infected cells determine NK cell cytotoxic activity and/or cytokine secretion. NK cell cytokine responses can be augmented in and can potentially contribute to multiple sclerosis (MS), an inflammatory disease of the central nervous system focused upon the oligodendrocytes (OLs). To investigate mechanisms by which NK cells may contribute to MS pathogenesis, we developed an in vitro human model of OL-NK cell interaction. We found that activated, but not resting human NK cells form conjugates with, and mediate cytotoxicity against, human oligodendrocytes. NK cells, when in conjugate with OLs, rapidly synthesize and polarize IFN-γ toward the OLs. IFN-γ is capable of reducing myelin oligodendrocyte and myelin associated glycoproteins (MOG and MAG) content. This activity is independent of MHC class-I mediated inhibition via KIR2DL1, but dependent upon the interaction between NK cell-expressed KIR2DL4 and its oligodendrocyte-expressed ligand, HLA-G. NK cells from patients with MS express higher levels of IFN-γ following conjugation to OLs, more actively promote in vitro reduction of MOG and MAG and have higher frequencies of the KIR2DL4 positive population. These data collectively suggest a mechanism by which NK cells can promote pathogenic effects upon OLs.


Subject(s)
Interferon-gamma/immunology , Killer Cells, Natural/immunology , Oligodendroglia/immunology , Receptors, KIR2DL4/immunology , Cell Line , Cytotoxicity, Immunologic/immunology , HLA-G Antigens/immunology , Humans , Multiple Sclerosis/immunology , Myelin-Associated Glycoprotein/immunology , Receptors, Natural Killer Cell/immunology
14.
Mymensingh Med J ; 27(4): 702-709, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30487483

ABSTRACT

Pneumonia is the leading cause of morbidity and mortality in children less than 5 years of age in developing countries like Bangladesh. Although WHO guideline classified severe pneumonia by symptoms and signs of the patients, radiological and laboratory investigations were not studied well. There was increasing number of cases of bronchiolitis which meet the criteria of WHO classified severe pneumonia are reported. The objective of the study was to assess the clinical and radiological parameters of severe pneumonia in 2 months to 59 months hospitalized children according to WHO guideline. This cross sectional study was conducted in pediatrics department of Mymensingh Medical College Hospital, Mymensingh, Bangladesh from July, 2015 to December 2015. Total 150 patients were included in this cross sectional study according to their clinical symptoms. Firstly, the chest x-ray was done in all the patients and radiographs were reviewed by an expert radiologist who was blind about the cases. Then the patients were classified as pneumonia and bronchiolitis according to the clinical features and radiology findings. Majority of the patients 83(55.3%) were between 2-6 months of age and mean age was 7.52±8.87. Maximum 105(70%) patients were male and 45(30%) were female. Most of them 70(47%) came from low middle class family. Regarding clinical features, all patients 150 had cough and chest indrawing. Ronchi found in 135(90%) patients, difficult breathing and fast breathing found in 130(87%) patients, crepitation in 122(81%) patients, wheeze in 93(62%) patients, dull on percussion in 36(21%) patients, bronchial breath sound in 25(17%) patients. Regarding radiological features, lobar consolidation was found in 18(12%) patients, patchy opacities in 42(28%) patients, which were radiological findings of pneumonia, while hyperinflation of lung present in 90(60%) patients, increased translucency in 82(54.6%), increased interstitial marking in 88(58.6%) patients, which were radiological findings of bronchiolitis. A total of 60(40%) admitted cases were diagnosed as pneumonia and 90(60%) cases diagnosed as bronchiolitis radiologically, which were predominant in WHO classified severe pneumonia (p<0.05). Wheeze was present in case of hyperinflation of lung in 78(83.8%), increased translucency in 67(72%) and increased interstitial marking in 70(75.2%) patients among radiological bronchiolitis (n=90). From above results we can concluded that Bronchiolitis was predominant among WHO guideline classified severe pneumonia.


Subject(s)
Bronchiolitis , Pneumonia , Bangladesh , Bronchiolitis/diagnostic imaging , Bronchiolitis/etiology , Child , Child, Preschool , Cross-Sectional Studies , Female , Humans , Infant , Male , Pneumonia/complications , Pneumonia/diagnostic imaging , Radiography
15.
Front Immunol ; 8: 1326, 2017.
Article in English | MEDLINE | ID: mdl-29085371

ABSTRACT

The ubiquitously expressed tyrosine phosphatase Src homology region 2 domain-containing phosphatase-2 (SHP-2, encoded by Ptpn11) is required for constitutive cellular processes including proliferation, differentiation, and the regulation of immune responses. During development and maturation, subsets of T cells express a variety of inhibitory receptors known to associate with phosphatases, which in turn, dephosphorylate key players of activating receptor signaling pathways. We hypothesized that SHP-2 deletion would have major effects on T cell development by altering the thresholds for activation, as well as positive and negative selection. Surprisingly, using mice conditionally deficient for SHP-2 in the T cell lineage, we show that the development of these lymphocytes is globally intact. In addition, our data demonstrate that SHP-2 absence does not compromise T cell effector functions, suggesting that SHP-2 is dispensable in these cells. Unexpectedly, in aging mice, Ptpn11 gene deletion driven by CD4 Cre recombinase leads to cartilage tumors in wrist bones in a T cell-independent manner. These tumors resemble miniature cartilaginous growth plates and contain CD4-lineage positive chondrocyte-like cells. Altogether these results indicate that SHP-2 is a cartilage tumor suppressor during aging.

16.
PLoS One ; 9(10): e111302, 2014.
Article in English | MEDLINE | ID: mdl-25333658

ABSTRACT

Type I interferons (IFN) are unique cytokines transcribed from intronless genes. They have been extensively studied because of their anti-viral functions. The anti-viral effects of type I IFN are mediated in part by natural killer (NK) cells. However, the exact contribution of type I IFN on NK cell development, maturation and activation has been somewhat difficult to assess. In this study, we used a variety of approaches to define the consequences of the lack of type I interferon receptor (IFNAR) signaling on NK cells. Using IFNAR deficient mice, we found that type I IFN affect NK cell development at the pre-pro NK stage. We also found that systemic absence of IFNAR signaling impacts NK cell maturation with a significant increase in the CD27+CD11b+ double positive (DP) compartment in all organs. However, there is tissue specificity, and only in liver and bone marrow is the maturation defect strictly dependent on cell intrinsic IFNAR signaling. Finally, using adoptive transfer and mixed bone marrow approaches, we also show that cell intrinsic IFNAR signaling is not required for NK cell IFN-γ production in the context of MCMV infection. Taken together, our studies provide novel insights on how type I IFN receptor signaling regulates NK cell development and functions.


Subject(s)
Immunity, Innate , Killer Cells, Natural/metabolism , Receptor, Interferon alpha-beta/metabolism , Adoptive Transfer , Animals , Bone Marrow Cells/immunology , Bone Marrow Cells/metabolism , Bone Marrow Cells/virology , Gene Expression Regulation, Developmental/genetics , Humans , Interferon-gamma/biosynthesis , Interferon-gamma/immunology , Killer Cells, Natural/immunology , Liver/immunology , Liver/metabolism , Liver/virology , Mice , Muromegalovirus/immunology , Muromegalovirus/pathogenicity , Organ Specificity , Receptor, Interferon alpha-beta/genetics , Receptor, Interferon alpha-beta/immunology , Signal Transduction
17.
J Vet Intern Med ; 27(4): 862-74, 2013.
Article in English | MEDLINE | ID: mdl-23663231

ABSTRACT

BACKGROUND: The detailed pathological phenotype of diet-responsive chronic enteropathy (CE) and its modulation with dietary therapy remain poorly characterized. HYPOTHESIS/OBJECTIVES: Key mucosal lesions of diet-responsive CE resolve with dietary therapy. METHODS: This was a prospective observational study of 20 dogs with diet-responsive CE. Endoscopic duodenal biopsies collected before and 6 weeks after the start of a dietary trial were assessed by means of qualitative and quantitative histopathological, immunohistochemical, and ultrastructural criteria. Control duodenal biopsies were obtained from 10 healthy Beagle dogs on 1 occasion. RESULTS: Compared with control dogs, the CE dogs had higher villus stunting scores and higher overall WSAVA scores, a lower villus height-to-width ratio, and higher lamina propria density of eosinophils. The CE dogs also had ultrastructural lesions of the mitochondria and brush border. In common with other studies in which the disease and control populations are not matched for breed, age, sex, and environment, these comparisons should be interpreted with caution. Comparing biopsies collected at presentation and 6 weeks after starting the dietary trial, mean lamina propria mononuclear cell score and lamina propria densities of eosinophils and mononuclear cells decreased. Dietary therapy also improved ultrastructural lesions of the mitochondria and brush border, eliciting a decrease in intermicrovillar space and an increase in microvillus height. CONCLUSIONS AND CLINICAL IMPORTANCE: In dogs with diet-responsive CE, the remission of clinical signs with dietary therapy is associated with subtle decreases in lamina propria density of eosinophils and mononuclear cells, and resolution of ultrastructural lesions of the enterocyte.


Subject(s)
Diet/veterinary , Dog Diseases/pathology , Duodenum/pathology , Enteritis/veterinary , Animal Feed/analysis , Animals , Biopsy , Chronic Disease , Dogs , Enteritis/diet therapy , Enteritis/pathology , Female , Male
18.
Blood ; 120(23): 4583-90, 2012 Nov 29.
Article in English | MEDLINE | ID: mdl-23034281

ABSTRACT

The SH2-containing inositol phosphatase-1 (SHIP-1) is a 5' inositol phosphatase known to negatively regulate the product of phosphoinositide-3 kinase (PI3K), phosphatidylinositol-3.4,5-trisphosphate. SHIP-1 can be recruited to a large number of inhibitory receptors expressed on natural killer (NK) cells. However, its role in NK cell development, maturation, and functions is not well defined. In this study, we found that the absence of SHIP-1 results in a loss of peripheral NK cells. However, using chimeric mice we demonstrated that SHIP-1 expression is not required intrinsically for NK cell lineage development. In contrast, SHIP-1 is required cell autonomously for NK cell terminal differentiation. These findings reveal both a direct and indirect role for SHIP-1 at different NK cell development checkpoints. Notably, SHIP-1-deficient NK cells display an impaired ability to secrete IFN-γ during cytokine receptor-mediated responses, whereas immunoreceptor tyrosine-based activation motif containing receptor-mediated responses is not affected. Taken together, our results provide novel insights on how SHIP-1 participates in the development, maturation, and effector functions of NK cells.


Subject(s)
Cell Differentiation/immunology , Interferon-gamma/immunology , Killer Cells, Natural/immunology , Phosphoric Monoester Hydrolases/immunology , Animals , Female , Flow Cytometry , Inositol Polyphosphate 5-Phosphatases , Interferon-gamma/metabolism , Interleukin Receptor Common gamma Subunit/genetics , Interleukin Receptor Common gamma Subunit/immunology , Interleukin Receptor Common gamma Subunit/metabolism , Killer Cells, Natural/metabolism , Lymphocyte Count , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , NK Cell Lectin-Like Receptor Subfamily A/immunology , NK Cell Lectin-Like Receptor Subfamily A/metabolism , NK Cell Lectin-Like Receptor Subfamily D/immunology , NK Cell Lectin-Like Receptor Subfamily D/metabolism , Phosphatidylinositol-3,4,5-Trisphosphate 5-Phosphatases , Phosphoric Monoester Hydrolases/genetics , Phosphoric Monoester Hydrolases/metabolism
19.
Br J Cancer ; 107(1): 123-8, 2012 Jun 26.
Article in English | MEDLINE | ID: mdl-22644299

ABSTRACT

BACKGROUND: Urinary biomarkers are needed to improve the care and reduce the cost of managing bladder cancer. Current biomarkers struggle to identify both high and low-grade cancers due to differing molecular pathways. Changes in microRNA (miR) expression are seen in urothelial carcinogenesis in a phenotype-specific manner. We hypothesised that urinary miRs reflecting low- and high-grade pathways could detect bladder cancers and overcome differences in genetic events seen within the disease. METHODS: We investigated urinary samples (n=121) from patients with bladder cancer (n=68) and age-matched controls (n=53). Fifteen miRs were quantified using real-time PCR. RESULTS: We found that miR is stable within urinary cells despite adverse handling and detected differential expression of 10 miRs from patients with cancer and controls (miRs-15a/15b/24-1/27b/100/135b/203/212/328/1224, ANOVA P<0.05). Individually, miR-1224-3p had the best individual performance with specificity, positive and negative predictive values and concordance of 83%, 83%, 75% and 77%, respectively. The combination of miRs-135b/15b/1224-3p detected bladder cancer with a high sensitivity (94.1%), sufficient specificity (51%) and was correct in 86% of patients (concordance). CONCLUSION: The use of this panel in patients with haematuria would have found 94% of urothelial cell carcinoma, while reducing cystoscopy rates by 26%. However, two invasive cancers (3%) would have been missed.


Subject(s)
Biomarkers, Tumor/urine , MicroRNAs/urine , Urinary Bladder Neoplasms/urine , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Sensitivity and Specificity , Urinary Bladder Neoplasms/diagnosis , Young Adult
20.
Oncogenesis ; 1: e11, 2012 May 07.
Article in English | MEDLINE | ID: mdl-23552639

ABSTRACT

Breast tumor kinase (BRK) is a non-receptor tyrosine kinase overexpressed in most human breast tumors, including lymph node metastases, but undetected in normal mammary tissue or in fibroadenomas. The activity of BRK-like Src family tyrosine kinase, is regulated negatively by phosphorylation of C-terminal tyrosine 447. Although the kinase that regulates BRK activation has not been identified, we and others have previously shown that BRK-Y447F is a constitutively active variant. Because BRK-Y447F significantly enhances the catalytic activity of the enzyme, we investigated the role of the constitutively active BRK variant in tumor formation and metastasis. Using stable breast cancer cell MDA-MB-231 we observed significantly enhanced rates of cell proliferation, migration and tumor formation in BRK-Y447F stable cells compared with wild-type stable cell lines. Our results indicate full activation of BRK is an essential component in the tumorigenic role of BRK.

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