Stromal Interferon-γ Signaling and Cross-Presentation Are Required to Eliminate Antigen-Loss Variants of B Cell Lymphomas in Mice

To study mechanisms of T cell-mediated rejection of B cell lymphomas, we developed a murine lymphoma model wherein three potential rejection antigens, human c-MYC, chicken ovalbumin (OVA), and GFP are expressed. After transfer into wild-type mice 60–70% of systemically growing lymphomas expressing all three antigens were rejected; lymphomas expressing only human c-MYC protein were not rejected. OVA expressing lymphomas were infiltrated by T cells, showed MHC class I and II upregulation, and lost antigen expression, indicating immune escape. In contrast to wild-type recipients, 80–100% of STAT1-, IFN-γ-, or IFN-γ receptor-deficient recipients died of lymphoma, indicating that host IFN-γ signaling is critical for rejection. Lymphomas arising in IFN-γ- and IFN-γ-receptor-deficient mice had invariably lost antigen expression, suggesting that poor overall survival of these recipients was due to inefficient elimination of antigen-negative lymphoma variants. Antigen-dependent eradication of lymphoma cells in wild-type animals was dependent on cross-presentation of antigen by cells of the tumor stroma. These findings provide first evidence for an important role of the tumor stroma in T cell-mediated control of hematologic neoplasias and highlight the importance of incorporating stroma-targeting strategies into future immunotherapeutic approaches

Transcriptomic alterations in the heart of non-obese type 2 diabetic Goto-Kakizaki rats

BACKGROUND: There is a spectacular rise in the global prevalence of type 2 diabetes mellitus (T2DM) due to the worldwide obesity epidemic. However, a significant proportion of T2DM patients are non-obese and they also have an increased risk of cardiovascular diseases. As the Goto-Kakizaki (GK) rat is a well-known model of non-obese T2DM, the goal of this study was to investigate the effect of non-obese T2DM on cardiac alterations of the transcriptome in GK rats. METHODS: Fasting blood glucose, serum insulin and cholesterol levels were measured at 7, 11, and 15 weeks of age in male GK and control rats. Oral glucose tolerance test and pancreatic insulin level measurements were performed at 11 weeks of age. At week 15, total RNA was isolated from the myocardium and assayed by rat oligonucleotide microarray for 41,012 genes, and then expression of selected genes was confirmed by qRT-PCR. Gene ontology and protein-protein network analyses were performed to demonstrate potentially characteristic gene alterations and key genes in non-obese T2DM. RESULTS: Fasting blood glucose, serum insulin and cholesterol levels were significantly increased, glucose tolerance and insulin sensitivity were significantly impaired in GK rats as compared to controls. In hearts of GK rats, 204 genes showed significant up-regulation and 303 genes showed down-regulation as compared to controls according to microarray analysis. Genes with significantly altered expression in the heart due to non-obese T2DM includes functional clusters of metabolism (e.g. Cyp2e1, Akr1b10), signal transduction (e.g. Dpp4, Stat3), receptors and ion channels (e.g. Sln, Chrng), membrane and structural proteins (e.g. Tnni1, Mylk2, Col8a1, Adam33), cell growth and differentiation (e.g. Gpc3, Jund), immune response (e.g. C3, C4a), and others (e.g. Lrp8, Msln, Klkc1, Epn3). Gene ontology analysis revealed several significantly enriched functional inter-relationships between genes influenced by non-obese T2DM. Protein-protein interaction analysis demonstrated that Stat is a potential key gene influenced by non-obese T2DM. CONCLUSIONS: Non-obese T2DM alters cardiac gene expression profile. The altered genes may be involved in the development of cardiac pathologies and could be potential therapeutic targets in non-obese T2DM

Over diagnosis of chronic obstructive pulmonary disease in an underserved patient population

Christian Ghattas,1 Allen Dai,2 David J Gemmel,3 Magdi H Awad2 1Department of Internal Medicine, St Elizabeth Health Center, Youngstown, OH, USA; 2Northeast Ohio Medical University College of Pharmacy, Rootstown, OH, USA; 3Department of Medical Education and Research, St Elizabeth Health Center, Youngstown, OH, USA Introduction: While cross-national studies have documented rates of chronic obstructive pulmonary disease (COPD) misdiagnosis among patients in primary care, US studies are scarce. Studies investigating diagnosis among uninsured patients are lacking. Objective: The purpose of this study is to identify patients who are over diagnosed and thus, mistreated, for COPD in a federally qualified health center. Methods: A descriptive study was conducted for a retrospective cohort from February 2011 to June 2012. Spirometry was performed by trained personnel following American Thoracic Society recommendations. Patients were referred for spirometry to confirm previous COPD diagnosis or to assess uncontrolled COPD symptoms. Airway obstruction was defined as a forced expiratory volume in the first second of expiration (FEV1) to forced vital capacity ratio less than 0.7. Reversibility was defined as a postbronchodilator increase in FEV1 greater than 200 mL and greater than 12%. Results: Eighty patients treated for a previous diagnosis of COPD (n = 72) or on anticholinergic inhalers (n = 8) with no COPD diagnosis were evaluated. The average age was 52.9 years; 71% were uninsured. Only 17.5% (14/80) of patients reported previous spirometry. Spirometry revealed that 42.5% had no obstruction, 22.5% had reversible obstruction, and 35% had nonreversible obstruction. Conclusion: Symptoms and smoking history are insufficient to diagnose COPD. Prevalence of COPD over diagnosis among uninsured patient populations may be higher than previously reported. Confirming previous COPD diagnosis with spirometry is essential to avoid unnecessary and potentially harmful treatment. Keywords: chronic obstructive pulmonary disease, COPD, misdiagnosis, over diagnosis, spirometry, uninsured, underserve

Adiponectin Single Nucleotide Polymorphism (+276G/T) and Its Possible Relation to Adiponectin Level in Egyptian Patients with Coronary Artery Disease

Increasing interest has been directed toward the role of the adiponectin gene polymorphism in the human genome and its implication in the pathogenesis of coronary artery disease. The present study was investigating the association between the single nucleotide polymorphism +276 G/T of the adiponectin gene with serum adiponectin level in patients with coronary artery disease (CAD). In this study 100 healthy controls and 100 Egyptian patients with coronary artery disease of both genders presented to the Cardiology Department of Suez Canal University Hospital were investigated. All subjects were genotyped for +276 G/T polymorphism of adiponectin gene. Lipid profile, fasting blood glucose were measured. Adiponectin and high sensitivity C-reactive protein levels were determined by ELISA technique. Polymerase chain reaction based on restriction fragment length polymorphism (PCR-RFLP) was used to determine the genotypes of the studied population. The lowest serum adiponectin value was observed in patients with CAD compared with control group. The T allele of SNP +276 G/T in the adiponectin gene was found to be associated with CAD (odd ratio 2.23; 95% CI: 1.44-3.45; P= 0.001). The significantassociation of the T allele (GT+TT) of this SNP with lower adiponectin level  and higher hsCRP levels was confirmed in the study (p= 0.003 and 0.006 respectively). Our results concluded that, +276 G/T SNP in the adiponectin gene is associated with CAD. Furthermore, carriers of the at-risk T allele had lower serum adiponectin level and higher serum hsCRP, causing in turn an increased risk to develop CAD.Key Words: Adiponectin gene; polymorphism; Coronary artery disease; PCR-RFL

Patterns of Thrombospondin Genes Polymorphisms in Acute Myocardial Infarction Patients in Ismailia City

Thrombospondin (TSP) 2 and 4 are multidomain calcium-binding extracellular glycoproteins which play a role in platelet aggregation and inflammatory response. TSP-2 has chemotactic and mitogenic activities for vascular smooth muscle cells while TSP-4 mRNA is expressed by endothelial and smooth muscle cells in vascular wall, and brain endothelial cells produce the protein both in vivo and in cell culture, localization consistent with its pro-atherogenic effects. These common functions may be central to the roles of the thrombospondins in coronary artery disease and myocardial infarction (MI). In the present study, the association of the TSP-2 (3949 TG, rs8089) and TSP-4 (Ala387Pro 1186 GC, rs1866389) gene variations and MI among Egyptian patients living in Ismailia city has been examined. Both rs8089 and rs1866389 were studied in 50 acute MI patients and 50 controls using Real-Time polymerase chain reaction. Theprevalence of TSP-2 and TSP-4 alleles was not different in MI patients compared to controls (P> 0.05). Although the minor allele homozygotes (GG) of TSP-2 seems to confer reduced risk of MI (OR: 0.42 95% CI=0.095-1.89) this was not statistically significant (P> 0.05). The distribution of different TSP-4 genotypes did not differ between MI patients and controls (P>0.05).Total cholesterol was statistically significantly higher (P=0.02) in carriers of minor allele (C) of TSP4 (GC+CC). Although, both polymorphisms showed no statistically significant difference in MI patients regarding all other measured conventional risk factors. However, the frequency of TTGC haplotype is statistically significantly higher in MI  patients (24%) than in controls (6%) [P value=0.0226]. Our data suggests that although association analysis with MI did not reach significance, an at-risk haplotype of common variants located in THBS2 and THBS4 may bepart of the genetic determinants for MI in the Egyptian population living in Ismailia city.Keywords: Myocardial infarction, Thrombospondin

Heme oxygenase-1 transduction in endothelial cells causes downregulation of monocyte chemoattractant protein-1 and of genes involved in inflammation and growth

Heme oxygenase (HO-1) has been implicated as an anti-inflammatory gene. HO-1 overexpression, transiently and chronically, affects heme protein expression, attenuates TNF-mediated cell death, and decreases adhesion molecules. We assessed the effect of oxidant-mediated agents such as glucose and heme on 8-epi-isoprostane PGF2alpha (8-epi-PGF2alpha) and monocyte chemoattractant protein-1 (MCP-1). Glucose and heme increased both 8-epi-PGF2alpha and MCP-1. Overexpression of HO-1 decreased both 8-epi-PGF2alpha and MCP-1. To identify target genes involved in HO-1-mediated regulation of inflammation, a serial analysis of gene expression mRNA profile was performed in endothelial cells (EC) overexpressing the human HO-1 gene by transduction of a retrovirus carrying the HO-1 gene. Gene arrays (differential displays among 2400 genes) were used to identify known and novel differentially expressed genes. The levels of expression for several genes were confirmed by real time PCR in cells overexpressing the HO-1 gene. In HO-1 overexpressing cells, VEGF and the prostaglandin transporter were greatly increased while MCP-1 levels were decreased by 2.5-fold. The data from this study are relevant to understanding the mechanisms underlying the pathophysiological effects of HO-1 deficiency on endothelial cell injury and inflammation

Effect Alpha Globlin Gene Deletion And Gamma Globin Gene -158 (C/T) Polymorphism In Beta-Thalassemic Patients

The beta-thalassemias (β- thalassemias) are among the most common autosomal recessive disorders. They have a remarkably high frequency in the Mediterranean region and represent one of the most common genetic diseases in Egypt. In this study, the spectrum of β- thalassemia mutations and genotype-to-phenotype correlations were defined in 32 β- thalassemic patients (β- thlassemias major and intermedia) with varying disease severity in two cities of the Suez Canal region. Ten different mutations were identified and the most frequent ones were: IVSI-6 (T-C) (37.5%), IVSI-110 (G-A) (34.4%) and both IVSI-1 (G-A), IVSII-745 (C-G) and -102 (C-G) (12.5% each). There was a wide spectrum of phenotypic severity in all patients. We studied the Xmn1 polymorphism (C/T) in γ- globin gene position -158 of β- thalassemia as a modulating factor of the disease severity. Presence of the polymorphism was found in two patients and this was not sufficient to explain the diversity of the phenotype encountered. Co-inheritance of alpha thalassaemia as a modulating factor was not evident in our patients. In conclusion, we have been unable to find a molecular basis for the benign clinical course in all our patients. Other genetic or acquired factors must be hypothesized which ameliorate the clinical condition. Keywords: β- thalassemia, Xmn1 polymorphism, &#945-globin gene deletion. Egyptian Journal of Biochemistry and Molecular Biology Vol. 26 (2) 2008: pp. 85-10

Heme oxygenase-1 transduction in endothelial cells causes downregulation of monocyte chemoattractant protein-1 and of genes involved in inflammation and growth

Heme oxygenase (HO-1) has been implicated as an anti-inflammatory gene. HO-1 overexpression, transiently and chronically, affects heme protein expression, attenuates TNF-mediated cell death, and decreases adhesion molecules. We assessed the effect of oxidant-mediated agents such as glucose and heme on 8-epi-isoprostane PGF2alpha (8-epi-PGF2alpha) and monocyte chemoattractant protein-1 (MCP-1). Glucose and heme increased both 8-epi-PGF2alpha and MCP-1. Overexpression of HO-1 decreased both 8-epi-PGF2alpha and MCP-1. To identify target genes involved in HO-1-mediated regulation of inflammation, a serial analysis of gene expression mRNA profile was performed in endothelial cells (EC) overexpressing the human HO-1 gene by transduction of a retrovirus carrying the HO-1 gene. Gene arrays (differential displays among 2400 genes) were used to identify known and novel differentially expressed genes. The levels of expression for several genes were confirmed by real time PCR in cells overexpressing the HO-1 gene. In HO-1 overexpressing cells, VEGF and the prostaglandin transporter were greatly increased while MCP-1 levels were decreased by 2.5-fold. The data from this study are relevant to understanding the mechanisms underlying the pathophysiological effects of HO-1 deficiency on endothelial cell injury and inflammation