33 research outputs found

    Studies on the immunomodulatory and anti-tumour activities of klebsiella K7 capsular antigen.

    Get PDF
    by Li Ho Kin.Thesis (M.Phil.)--Chinese University of Hong Kong, 1997.Includes bibliographical references (leaves 213-245).ACKNOWLEDGEMENTS --- p.iABBREVIATIONS --- p.iiiABSTRACT --- p.viiiTABLE OF CONTENTS --- p.xiChapter CHAPTER 1: --- GENERAL INTRODUCTION --- p.1Chapter 1.1 --- Introduction --- p.2Chapter 1.2 --- Effector Cells Mediating Anti-Tumour Immunity --- p.5Chapter 1.2.1 --- Cytotoxic T Lymphocytes --- p.6Chapter 1.2.2 --- Natural Killer Cells --- p.7Chapter 1.2.3 --- Lymphokine-Activated Killer Cells --- p.9Chapter 1.2.4 --- Macrophages --- p.10Chapter 1.2.5 --- Tumour-Infiltrating Lymphocytes --- p.12Chapter 1.3 --- Current Modalities for Cancer Treatment --- p.13Chapter 1.3.1 --- Surgery --- p.13Chapter 1.3.2 --- Radiation Therapy --- p.14Chapter 1.3.3 --- Chemotherapy --- p.14Chapter 1.3.4 --- Biologic Therapy --- p.15Chapter 1.4 --- Biological Response Modifiers as Cancer Therapeutics --- p.17Chapter 1.4.1 --- Monoclonal Antibodies --- p.20Chapter 1.4.2 --- Differentiating Agents --- p.21Chapter 1.4.3 --- Cytokines --- p.24Chapter 1.4.4 --- Bioactive Plant Polysaccharides --- p.30Chapter 1.5 --- Bacterial Polysaccharides as Potential Immunomodulators and Anti-Tumour Agents --- p.36Chapter 1.5.1 --- General Properties of Bacterial Polysaccharides --- p.36Chapter 1.5.2 --- Structure and Function of Bacterial Polysaccharides --- p.37Chapter 1.5.3 --- Immunomodulatory and Anti-Tumour Activities of Bacterial Polysaccharides --- p.39Chapter 1.5.4 --- General Properties of Klebsiella K7 Capsular Antigen --- p.41Chapter 1.6 --- Aims and Scopes of the Investigation --- p.44Chapter CHAPTER 2: --- MATERIALS AND METHODS --- p.46Chapter 2.1 --- Materials --- p.47Chapter 2.1.1 --- Animals --- p.47Chapter 2.1.2 --- Klebsiella pneumoniae Serotype7 --- p.47Chapter 2.1.3 --- Agar Medium for Cultivation of Klebsiella pneumoniae Serotype7 --- p.47Chapter 2.1.4 --- Cell Lines --- p.47Chapter 2.1.5 --- "Buffers, Culture Medium and Other Reagents" --- p.49Chapter 2.1.6 --- Antibodies --- p.54Chapter 2.1.7 --- Radioisotopes --- p.55Chapter 2.1.8 --- Recombinant Cytokines --- p.55Chapter 2.1.9 --- Oligonucleotide Primers and Internal Probes --- p.56Chapter 2.1.10 --- Reagents and Solutions for Gene Expression Analysis --- p.59Chapter 2.2 --- Methods --- p.64Chapter 2.2.1 --- "Extraction, Purification and Characterization of Klebsiella K7 Capsular Antigen" --- p.54Chapter 2.2.1.1 --- Extraction and Purification of K7 Capsular Antigen --- p.64Chapter 2.2.1.2 --- Gel Filtration of K7 Capsular Antigen --- p.65Chapter 2.2.1.3 --- Characterization of K7 Capsular Antigen --- p.67Chapter 2.2.1.4 --- Determination of the Bio-Toxicity of K7 Capsular Antigen --- p.67Chapter 2.2.1.5 --- In Vitro Cytotoxicity of K7 Capsular Antigen on Splenocytes --- p.53Chapter 2.2.2 --- Assay for the Hematopoietic and Mitogenic Activities of Klebsiella K7 Capsular Antigen --- p.69Chapter 2.2.2.1 --- Isolation and Preparation of Cells --- p.69Chapter 2.2.2.2 --- In Vitro Lymphocyte Transformation Assay --- p.70Chapter 2.2.2.3 --- In Vitro Assay of Thymocyte Proliferation --- p.70Chapter 2.2.2.4 --- Depleting Mouse T Cells by Anti-Thy-1.2 Antibody Plus Complement Treatment --- p.71Chapter 2.2.2.5 --- Depleting Mouse B Cells by Anti-mouse B Cell Antibody Plus Complement Treatment --- p.71Chapter 2.2.2.6 --- Depleting Macrophages from Spleen Cell Suspension --- p.71Chapter 2.2.2.7 --- Flow Cytometric Analysis of Different Cell Populations from Splenocytes --- p.72Chapter 2.2.2.8 --- In Vitro Assay of rmIL-3-Stimulated Proliferation of Murine Bone Marrow Cells --- p.73Chapter 2.2.2.9 --- In Vitro Cytotoxicity of K7 Capsular Antigen on Bone Marrow Cells --- p.73Chapter 2.2.2.10 --- Colony Assay of Murine Bone Marrow Cells --- p.73Chapter 2.2.2.11 --- Assay of Differentiation of Murine Bone Marrow Cells --- p.74Chapter 2.2.3 --- Assay for Macrophage Activating Activities of Klebsiella K7 Capsular Antigen --- p.75Chapter 2.2.3.1 --- Preparation of Murine Peritoneal Exudate Cells (PEC) --- p.75Chapter 2.2.3.2 --- Assay of Phagocytic Activity of Peritoneal Macrophages --- p.75Chapter 2.2.3.3 --- In Vitro Macrophage-Mediated Cytostatic Activity --- p.76Chapter 2.2.3.4 --- Nitric Oxide (NO) Production of Peritoneal Macrophages --- p.76Chapter 2.2.3.5 --- In Vivo Migration of Macrophages --- p.77Chapter 2.2.3.6 --- Tumour Necrosis Factor (TNF) Production by Peritoneal Macrophages --- p.77Chapter 2.2.3.7 --- TNF Bioassay --- p.78Chapter 2.2.3.8 --- Gene Expression Analysis in Peritoneal Macrophages --- p.78Chapter 2.2.3.8.1 --- Preparation of Cell Lysate --- p.78Chapter 2.2.3.8.2 --- RNA Isolation --- p.79Chapter 2.2.3.8.3 --- Reverse Transcription of RNA --- p.80Chapter 2.2.3.8.4 --- Polymerase Chain Reaction (PCR) --- p.80Chapter 2.2.3.8.5 --- Agarose Gel Electrophoresis --- p.82Chapter 2.2.3.8.6 --- 3' End Labelling of Oligonucleotide Probes --- p.82Chapter 2.2.3.8.7 --- Dot Blot Hybridization --- p.83Chapter 2.2.3.8.8 --- DIG Chemiluminescent Detection --- p.83Chapter 2.2.4 --- Assay for Anti-Tumour Activities of Klebsiella K7 Capsular Antigen --- p.85Chapter 2.2.4.1 --- Assay of Tumour Cell Proliferation --- p.85Chapter 2.2.4.2 --- Assay of Anti-Tumour Activity In Vivo --- p.85Chapter 2.2.4.3 --- Assay of Lymphokine-Activated Killer Cell Activity --- p.85Chapter 2.2.4.4 --- Assay of Natural Killer Cell Activity --- p.87Chapter 2.2.4.5 --- Assay for Differentiation-Associated Characteristics of Myeloid Leukemia Cells --- p.88Chapter 2.2.4.5.1 --- Determination of the Viability of Myeloid Leukemia JCS cells --- p.88Chapter 2.2.4.5.2 --- Assessment of Cell Morphology --- p.88Chapter 2.2.4.5.3 --- Surface Antigen Immunophenotyping --- p.88Chapter 2.2.4.5.4 --- Assay of Non-specific Esterase Activity --- p.89Chapter 2.2.4.5.5 --- Assay of Phagocytosis --- p.90Chapter 2.2.5 --- Statistical Analysis --- p.90Chapter CHAPTER 3: --- "EXTRACTION, PURIFICATION & CHARACTERIZATION OF KLEBSIELLA K7 CAPSULAR ANTIGEN" --- p.91Chapter 3.1 --- Introduction --- p.92Chapter 3.2 --- Results --- p.94Chapter 3.2.1 --- Extraction and Purification of K7 Capsular Antigen from Klebsiella pneumoniae Serotype7 --- p.94Chapter 3.2.2 --- Gel Filtration Chromatography of K7 Capsular Antigen --- p.94Chapter 3.2.3 --- Characterization of K7 Capsular Antigen --- p.97Chapter 3.2.4 --- Determination of Bio-toxicity and Cellular Toxicity of K7 Capsular Antigen --- p.97Chapter 3.3 --- Discussion --- p.101Chapter CHAPTER 4: --- HEMATOPOIETIC AND MITOGENIC ACTIVITIES OF KLEBSIELLA K7 CAPSULAR ANTIGEN --- p.103Chapter 4.1 --- Introduction --- p.104Chapter 4.2 --- Results --- p.107Chapter 4.2.1 --- Effect of K7 Capsular Antigen on the In Vitro Proliferation of Murine Bone Marrow Cells --- p.107Chapter 4.2.2 --- Effect of K7 Capsular Antigen on rmIL-3-Stimulated Proliferation of Murine Bone Marrow Cells --- p.107Chapter 4.2.3 --- Effect of K7 Capsular Antigen on the In Vitro Differentiation of Murine Bone Marrow Cells --- p.112Chapter 4.2.4 --- Effect of K7 Capsular Antigen on the In Vitro Murine Bone Marrow Colony Formation --- p.112Chapter 4.2.5 --- Effect of K7 Capsular Antigen on the Viability of Splenocytes In Vitro --- p.117Chapter 4.2.6 --- In Vitro Mitogenic Effect of K7 Capsular Antigen on Splenocytes and Thymocytes --- p.117Chapter 4.2.7 --- Characterization of the Lymphocyte Population(s) Responding to K7 Capsular Antigen --- p.121Chapter 4.2.8 --- Effect of Polymyxin B Sulphate on the Mitogenic Activity of K7Capsular Antigen --- p.125Chapter 4.2.9 --- In Vivo Mitogenic Activity of K7 Capsular Antigen --- p.125Chapter 4.2.10 --- Flow Cytometric Analysis of Splenocytes from K7 Capsular Antigen-Treated Mice --- p.128Chapter 4.2.11 --- In Vitro Co-mitogenic Activity of K7 Capsular Antigen --- p.128Chapter 4.3 --- Discussion --- p.132Chapter CHAPTER 5: --- ACTIVATION OF MACROPHAGES BY KLEBSIELLA K7CAPSULAR ANTIGEN --- p.136Chapter 5.1 --- Introduction --- p.137Chapter 5.2 --- Results --- p.140Chapter 5.2.1 --- Effect of K7 Capsular Antigen on the Phagocytic Activity of Macrophages In Vitro --- p.140Chapter 5.2.2 --- Effect of K7 Capsular Antigen on the In Vivo Migration of Macrophages --- p.140Chapter 5.2.3 --- Effect of K7 Capsular Antigen on the In Vitro Cytostatic Activity of Picolinic Acid (PLA)-Activated Macrophages --- p.144Chapter 5.2.4 --- Effect of K7 Capsular Antigen on Nitric Oxide (NO) Production by Macrophages In Vitro --- p.144Chapter 5.2.5 --- Effect of K7 Capsular Antigen on the In Vitro Production of Tumour Necrosis Factor (TNF) by Macrophages --- p.148Chapter 5.2.6 --- Effect of K7 Capsular Antigen on the In Vitro Induction of Gene Expression in Macrophages --- p.148Chapter 5.3 --- Discussion --- p.166Chapter CHAPTER 6: --- ANTI-TUMOUR ACTIVITIES OF KLEBSIELLA K7 CAPSULAR ANTIGEN --- p.171Chapter 6.1 --- Introduction --- p.172Chapter 6.2 --- Results --- p.174Chapter 6.2.1 --- Effect of K7 Capsular Antigen In Vitro Growth of Various Tumour Cell Lines --- p.174Chapter 6.2.2 --- Effect of K7 Capsular Antigen on the In Vitro Growth of EAT Cells --- p.174Chapter 6.2.3 --- Effect of K7 Capsular Antigen on the Activation of LAK cells --- p.185Chapter 6.2.4 --- Effect of K7 Capsular Antigen on the Activation of NK Cells --- p.185Chapter 6.2.5 --- Effect of K7 Capsular Antigen on the Induction of Monocytic Differentiation of the Murine Myeloid Leukemia JCS Cells --- p.185Chapter 6.2.5.1 --- Effect of K7 Capsular Antigen on the Induction of Morphological Changes of JCS Cells --- p.188Chapter 6.2.5.2 --- Effect of K7 Capsular Antigen on the Expression of Macrophage Differentiation Antigen on Leukemia JCS Cells --- p.192Chapter 6.2.5.3 --- Effect of K7 Capsular Antigen on the Induction of Non-specific Esterase Activity in Leukemia JCS Cells --- p.192Chapter 6.2.5.4 --- Effect of K7 Capsular Antigen on the Stimulation of Phagocytic Activity in Leukemia JCS Cells --- p.192Chapter 6.3 --- Discussion --- p.198Chapter CHAPTER 7: --- CONCLUSIONS & FUTURE PERSPECTIVES --- p.202REFERENCES --- p.21

    Phenotypic and Metabolic Plasticity In Canine Cellular Reprogramming

    Get PDF
    Embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) derived from large mammals reproduce few characteristics displayed by rodent or human counterparts. This is complicated by the inherent plasticity of mammalian ESC/iPSC cultures that resemble a variety of developmental stages including the naïve and primed pluripotent states. Defining the extrinsic signals that modulate the developmental identity of canine ESC/iPSC (i.e. primed versus naïve) will improve knowledge integration with more sophisticated rodent and primate research. In this thesis, I sought to determine if manipulation of the culture environment can promote nuclear and metabolic reprogramming of canine cell lines towards a more primitive state of pluripotency. Using growth factors and kinase inhibitors to modulate pluripotency of canine ESCs (cESCs), I demonstrated that cESCs exhibit the plasticity to adopt multiple developmental identities. I observed that lineage-specific differentiation of cESCs is influenced by pluripotent state modulation, coincident with changes to colony architecture, transcriptional and epigenetic markers of developmental maturity. I found that primed- and naïve-like cESCs exhibit pluripotent-state specific mitochondrial structure and function, including differential reliance on glucose oxidation pathways for steady-state proliferation in vitro. Lastly, using comparative sequence analysis and biochemical assays, I observed that evolutionary differences in genomic CpG density at pluripotency-associated promoters correlate with functionally relevant cytosine modifications to the induction and maintenance of pluripotency. I showed the utility of physiological metabolites that regulate 5-methylcytosine oxidation in promoting cellular and transcriptional features associated with early nuclear reprogramming of canine fibroblasts (e.g. mesenchymal-to-epithelial transition). Taken together, my work establishes a binary cESC model of primed- and naïve-pluripotent states, providing insight into shared and divergent features of pluripotency progression and acquisition in placental mammals

    Psr1p interacts with SUN/sad1p and EB1/mal3p to establish the bipolar spindle

    Get PDF
    Regular Abstracts - Sunday Poster Presentations: no. 382During mitosis, interpolar microtubules from two spindle pole bodies (SPBs) interdigitate to create an antiparallel microtubule array for accommodating numerous regulatory proteins. Among these proteins, the kinesin-5 cut7p/Eg5 is the key player responsible for sliding apart antiparallel microtubules and thus helps in establishing the bipolar spindle. At the onset of mitosis, two SPBs are adjacent to one another with most microtubules running nearly parallel toward the nuclear envelope, creating an unfavorable microtubule configuration for the kinesin-5 kinesins. Therefore, how the cell organizes the antiparallel microtubule array in the first place at mitotic onset remains enigmatic. Here, we show that a novel protein psrp1p localizes to the SPB and plays a key role in organizing the antiparallel microtubule array. The absence of psr1+ leads to a transient monopolar spindle and massive chromosome loss. Further functional characterization demonstrates that psr1p is recruited to the SPB through interaction with the conserved SUN protein sad1p and that psr1p physically interacts with the conserved microtubule plus tip protein mal3p/EB1. These results suggest a model that psr1p serves as a linking protein between sad1p/SUN and mal3p/EB1 to allow microtubule plus ends to be coupled to the SPBs for organization of an antiparallel microtubule array. Thus, we conclude that psr1p is involved in organizing the antiparallel microtubule array in the first place at mitosis onset by interaction with SUN/sad1p and EB1/mal3p, thereby establishing the bipolar spindle.postprin

    Removal of antagonistic spindle forces can rescue metaphase spindle length and reduce chromosome segregation defects

    Get PDF
    Regular Abstracts - Tuesday Poster Presentations: no. 1925Metaphase describes a phase of mitosis where chromosomes are attached and oriented on the bipolar spindle for subsequent segregation at anaphase. In diverse cell types, the metaphase spindle is maintained at a relatively constant length. Metaphase spindle length is proposed to be regulated by a balance of pushing and pulling forces generated by distinct sets of spindle microtubules and their interactions with motors and microtubule-associated proteins (MAPs). Spindle length appears important for chromosome segregation fidelity, as cells with shorter or longer than normal metaphase spindles, generated through deletion or inhibition of individual mitotic motors or MAPs, showed chromosome segregation defects. To test the force balance model of spindle length control and its effect on chromosome segregation, we applied fast microfluidic temperature-control with live-cell imaging to monitor the effect of switching off different combinations of antagonistic forces in the fission yeast metaphase spindle. We show that spindle midzone proteins kinesin-5 cut7p and microtubule bundler ase1p contribute to outward pushing forces, and spindle kinetochore proteins kinesin-8 klp5/6p and dam1p contribute to inward pulling forces. Removing these proteins individually led to aberrant metaphase spindle length and chromosome segregation defects. Removing these proteins in antagonistic combination rescued the defective spindle length and, in some combinations, also partially rescued chromosome segregation defects. Our results stress the importance of proper chromosome-to-microtubule attachment over spindle length regulation for proper chromosome segregation.postprin

    NLRC5: Ein NLR Protein mit Einfluss auf angeborene und adaptive Immunmechanismen und seine protektive Rolle im Verlauf einer Kolitis

    Get PDF
    NLRC5 was reported to influence the expression of IFNs and NF κB target genes as well as the production of IL 1β. However, its impact is still controversial. NLRC5 was identified to share several features with CIITA, an NLR member that functions as co-transcriptional activator for MHC class II-encoding genes and is therefore essential for adaptive immunity. In analogy, NLRC5 was reported to initiate the transcription of MHC class I-encoding genes. This study aimed to define the contribution of NLRC5 to innate as well as adaptive immune mechanisms. Nlrc5-deficient (ko) mice were generated. They were viable and fertile and had no obvious immune defects under SPF-housing conditions. NLRC5 was predominantly expressed in immune tissues and potently induced by IFNɣ. In accordance with its role as transcriptional regulator, Nlrc5 ko mice had a severely decreased MHC class I surface expression. However, a residual, cell type-dependent MHC class I expression remained. Furthermore, MHC class I was still inducible in Nlrc5-deficient cells, which pointed to the existence of other MHC I regulating mechanisms. It is assumed that one of these mechanisms is the transcriptional activation of MHC class I-coding genes by CIITA. Decreased MHC class I levels led to an impaired generation of CD8+ T lymphocytes in Nlrc5 ko mice. The MHC class II+ cell population was increased, but did not affect the number of CD4+ T lymphocytes. Next to adaptive immune functions, NLRC5 was involved in innate immune signaling pathways. The protein was crucial for a proper induction of type I and II IFNs as well as IL 1β. The diminished CD8+ T cell population and the impaired production of IFNγ and IL 1β were presumed to render Nlrc5 ko mice less susceptible to intestinal inflammation. In contrast this work revealed that ko mice develop an aggravated DSS-induced colitis. The pronounced phenotype correlated with an enhanced epithelial destruction and an upregulated production of inflammatory cytokines.Ein Einfluss von NLRC5 auf die Induktion von Interferonen und NF κB Zielgenen sowie die IL 1β-Produktion wurde postuliert. Dieser Einfluss wird jedoch kontrovers diskutiert. Es Desweiteren weist NLRC5 diverse Gemeinsamkeiten mit dem NLR Protein CIITA auf, welcher als translationaler Ko-Transaktivator an MHC II-kodierender Gene fungiert und somit essenziel für die adaptive Immunität ist. Analog initiiert NLRC5 die Transkription MHC I kodierender Gene. Diese Studie sollte untersuchen inwieweit NLRC5 zu angeborenen oder erworbenen Immunprozessen beiträgt. Nlrc5-defiziente (Ko) Mäuse wurden generiert. Diese wiesen unter SPF-Haltungsbedingungen keine erkennbaren Immundefekte auf. NLRC5 wurde vor allem in Immungeweben exprimiert und durch IFNɣ induziert. Die Oberflächenexpression von MHC I in Nlrc5 Ko Mäusen war stark vermindert. Trotzdem verblieb eine Zelltyp-spezifische MHC I Expression und Induzierbarkeit. Dies deutete auf die Existenz weiterer MHC I-regulierender Mechanismen von denen einer möglicherweise die transkriptionelle Aktivierung MHC I-kodierender Gene durch CIITA ist. Die reduzierten MHC I-Spiegel in Nlrc5-Ko Mäusen beeinträchtigten die Generation von CD8+ T Zellen. Die MHC II+ Zellpopulation war vergrößert, was sich jedoch nicht auf die Anzahl CD4+ T Zellen auswirkte. Neben den Einflüssen auf das adaptive Immunsystem wirkte sich NLRC5 auch auf die Signalwege der angeborenen Immunität aus. Das Protein war an der Induktion von Typ I und II Interferonen sowie der Produktion von IL 1β beteiligt. Aufgrund der verminderten Anzahl CD8+ T Zellen und der beeinträchtigten Produktion von IFNɣ und IL 1β wurde angenommen, dass Nlrc5 Ko Mäuse weniger empfänglich für die Induktion einer intestinalen Entzündung sind. Hier konnte hingegen gezeigt werden, dass Nlrc5-Ko Mäuse eine stärkere DSS-induzierte Kolitis entwickeln. Der ausgeprägte Phänotyp korrelierte mit einer gesteigerten epithelialen Destruktion und der erhöhten Produktion inflammatorischer Zytokine

    Glutathione, the redox sensitive transcription factors AP-1 and NF-kB, and early one adenoviral protein in human lung in smoking related lung disease

    Get PDF
    The major factor in the development of chronic obstructive airways disease (COPD) is cigarette smoking, although not all smokers develop chronic obstructive pulmonary disease. Inflammation and destruction has been shown in the lungs of smokers with chronic obstructive pulmonary disease. Oxidative stress, both from cigarette smoke and oxidants generated endogenously by cellular processes, contribute to the inflammation that occurs in the lungs in chronic obstructive pulmonary disease. It remains unclear why certain individuals appear susceptible to the effects of cigarette smoke and go on to develop inflammation and airflow limitation. The glutathione redox system is an important antioxidant protective system within the lungs, and this system may play a critical role in the development of inflammation. An alteration in the transcription of pro-inflammatory cytokines and mediators is also likely to contribute to the inflammation within the lung. Nuclear factor kappa-B (NF-kB) and activator protein-1 (AP-1) are both redox sensitive transcription factors, and are involved in the regulation of the gene transcription of many pro-inflammatory mediators. Activator protein-1 and nuclear factor kappa-B have a close relationship with y-glutamylcysteine synthetase (y-GCS) (glutamate cysteine ligase, GCL), the rate limiting enzyme in the synthesis of glutathione, with the y-glutamylcysteine synthetase gene containing various elements including an Activator protein-1 binding site. Susceptibility to the effects of cigarette smoke is likely to explain why certain individuals develop chronic obstructive pulmonary disease, and this susceptibility may arise from an earlier viral infection such as adenoviral infection that lies dormant, but which in the face of an oxidant stimulus such as cigarette smoke augments the inflammatory process.The in vivo studies herein have examined glutathione and y-glutamylcysteine synthetase, gene transcription, oxidant/antioxidant imbalance, the redox sensitive transcription factors nuclear factor kappa-B and activator protein-1, and have assessed for the presence of the early one adenoviral protein in human lung in smokers and patients with COPD.The results show similar levels of total glutathione in the lungs of patients with and without airflow obstruction, and decreased y-glutamylcysteine synthetase activity in patients with severe airflow obstruction who have undergone lung volume reduction surgery for emphysema compared to those with no airflow obstruction. Local lung oxidative stress as measured by malondialdehyde, and trolox equivalant antioxidant capacity a marker of systemic oxidative stress did not correlate with lung function. DNA binding of Nuclear factor kappa-B correlated with lung function as measured by percent predicted forced expiratory volume in one second (FEVi), however no such relationship was found with Activator protein-1 DNA binding. Examination for early one adenoviral gene and protein in human lung tissue failed to reveal conclusive results.In conclusion levels of glutathione in human lung tissue, oxidative stress including both lung and systemic oxidative stress, and the DNA binding of activator protein-1 in lung are not related to the degree of airflow obstruction present

    Antioxidant and DPPH-Scavenging Activities of Compounds and Ethanolic Extract of the Leaf and Twigs of Caesalpinia bonduc L. Roxb.

    Get PDF
    Antioxidant effects of ethanolic extract of Caesalpinia bonduc and its isolated bioactive compounds were evaluated in vitro. The compounds included two new cassanediterpenes, 1α,7α-diacetoxy-5α,6β-dihydroxyl-cass-14(15)-epoxy-16,12-olide (1)and 12α-ethoxyl-1α,14β-diacetoxy-2α,5α-dihydroxyl cass-13(15)-en-16,12-olide(2); and others, bonducellin (3), 7,4’-dihydroxy-3,11-dehydrohomoisoflavanone (4), daucosterol (5), luteolin (6), quercetin-3-methyl ether (7) and kaempferol-3-O-α-L-rhamnopyranosyl-(1Ç2)-β-D-xylopyranoside (8). The antioxidant properties of the extract and compounds were assessed by the measurement of the total phenolic content, ascorbic acid content, total antioxidant capacity and 1-1-diphenyl-2-picryl hydrazyl (DPPH) and hydrogen peroxide radicals scavenging activities.Compounds 3, 6, 7 and ethanolic extract had DPPH scavenging activities with IC50 values of 186, 75, 17 and 102 μg/ml respectively when compared to vitamin C with 15 μg/ml. On the other hand, no significant results were obtained for hydrogen peroxide radical. In addition, compound 7 has the highest phenolic content of 0.81±0.01 mg/ml of gallic acid equivalent while compound 8 showed the highest total antioxidant capacity with 254.31±3.54 and 199.82±2.78 μg/ml gallic and ascorbic acid equivalent respectively. Compound 4 and ethanolic extract showed a high ascorbic acid content of 2.26±0.01 and 6.78±0.03 mg/ml respectively.The results obtained showed the antioxidant activity of the ethanolic extract of C. bonduc and deduced that this activity was mediated by its isolated bioactive compounds

    A licence to kill: interaction of alphaherpesviruses with Natural Killer (NK) cells

    Get PDF
    We describe the identified mechanisms of PRV gD, PRV gB and PRV US3 to modulate NK cell activity. We've identified PRV gD to reduce DNAM-1 binding, PRV US3 to increase CD300a binding and a yet NK cell-activating effect of PRV gB
    corecore