1.
Bhandage, Amol K., 1988-
(författare)
Glutamate and GABA signalling components in the human brain and in immune cells
2016
Doktorsavhandling (övrigt vetenskapligt/konstnärligt) abstract
Glutamate and γ-aminobutyric acid (GABA) are the principal excitatory and inhibitory neurotransmitters in the central nervous system (CNS). They both can activate their ionotropic and metabotropic receptors. Glutamate activates ionotropic glutamate receptors (iGlu - AMPA, kainate and NMDA receptors) and GABA activates GABA-A receptors which are modulated by many types of drugs and substances including alcohol. Using real time quantitative polymerase chain reaction, I have shown that iGlu and/or GABA-A receptor subunits were expressed in the hippocampus dentate gyrus (HDG), orbitofrontal cortex (OFC), dorsolateral prefrontal cortex (DL-PFC), central amygdala (CeA), caudate and putamen of the human brain and their expression was altered by chronic excessive alcohol consumption. It indicates that excitatory and inhibitory neurotransmission may have been altered in the brain of human alcoholics. It is possible that changes in one type of neurotransmitter system may drive changes in another. These brain regions also play a role in brain reward system. Any changes in them may lead to changes in the normal brain functions.Apart from the CNS, glutamate and GABA are also present in the blood and can be synthesised by pancreatic islet cells and immune cells. They may act as immunomodulators of circulating immune cells and can affect immune function through glutamate and GABA receptors. I found that T cells from human, rat and mouse lymph nodes expressed the mRNAs and proteins for specific GABA-A receptor subunits. GABA-evoked transient and tonic currents recorded using the patch clamp technique demonstrate the functional GABA-A channel in T cells. Furthermore, the mRNAs for specific iGlu, GABA-A and GABA-B receptor subunits and chloride cotransporters were detected in peripheral blood mononuclear cells (PBMCs) from men, non-pregnant women, healthy and depressed pregnant women. The results indicate that the expression of iGlu, GABA-A and GABA-B receptors is related to gender, pregnancy and mental health and support the notion that glutamate and GABA receptors may modulate immune function. Intra- and interspecies variability exists in the expression and it is further influenced by physiological conditions.
2.
Boij, Roland, 1952-
(författare)
Aspects of inflammation, angiogenesis and coagulation in preeclampsia
2016
Doktorsavhandling (övrigt vetenskapligt/konstnärligt) abstract
Preeclampsia is a major challenge to obstetricians, due to its impact on maternal and fetal morbidity and mortality and the lack of preventive and treatment strategies. The overall aim of this thesis is to increase the knowledge of the pathogenesis of preeclampsia including the role of inflammation, angiogenesis and coagulation, both locally at the fetomaternal interface and in the maternal circulation. Uncompensated maternal endothelial inflammatory responses to factors from stressed trophoblasts seem to be a major contributor to the syndrome, together with an imbalance in angiogenesis and an activated coagulation system. An increasing amount of data indicates an involvement of the immune system with defect tolerance to the conceptus as an integral part of the pathogenesis, at least in early-onset preeclampsia (EOP).We showed that a single administration of human preeclampsia serum in pregnant IL-10−/− mice induced the full spectrum of preeclampsia-like symptoms including hypoxic injury in uteroplacental tissues and endotheliosis in maternal kidneys. Importantly, preeclampsia serum, as early as 12 to 14 weeks of gestation, disrupted cross talk between trophoblasts and endothelial cells in an in vitro model of endovascular activity (Tube formation test). These results indicate that preeclamptic sera can be used to better understand the pathophysiology and to predict the disorder. Preeclampsia has been associated with increased inflammation, aberrant angiogenesis and activated coagulation, but their correlation and relative contribution are unknown. We found that markers for all these mechanisms were independently associated with preeclampsia. Cytokines, chemokines, and complement factors seem all to be part of a Th1-associated inflammatory reaction in preeclampsia, more pronounced in EOP than in late-onset preeclampsia (LOP), in line with a more homogeneous pathogenesis in EOP as based on placental pathology. In women with intrauterine growth restriction (IUGR), with an anticipated pathologic placentation, only differences in levels for sFlt-1 and PlGF were found in comparison with mothers without IUGR. Thus, sFlt-1 and PlGF seem to be indicators of placental pathology, while other biomarkers might also reflect maternal endothelial pathology. Chemokines, in contrast to cytokines, may prove to be useful markers in preeclampsia.A deficiency in regulatory T (Treg) cells causing reduced immune regulatory capacity has been proposed in preeclampsia. Utilizing recent advances in flow cytometry phenotyping, we found no major alterations in circulating Treg numbers in preeclamptic women compared with normal pregnant and non-pregnant women. However, preeclampsia was associated with increased fractions of CTLA-4+ and CCR4+ cells within Treg subpopulations, which is in line with a migratory defect of Treg cells, and potentially associated with a reduced number of suppressive Treg cells at the fetomaternal interface. As we found that corticosteroid treatment affected the results, it should be accounted for in studies of EOP. Chemokines are supposed to be part of the immune adaptation in pregnancy. We found a decreased expression of CCL18 (Th2/Tregassociated), in trophoblasts from preeclamptic compared to normal pregnant women, indicating a local regulatory defect in preeclampsia, in line with our finding of a possible migratory defect of circulating Treg cells. Due to increased expression of CCL20 (Th17) and CCL22 (Th2) in first trimester placenta and increased circulating levels of CXCL10 (Th1) and CCL20 (Th17) in third trimester preeclamptic women, we suggest that CCL20 and CCL22 may be important for implantation and early placentation while in third trimester of a preeclamptic pregnancy CXCL10 and CCL20 mainly mirror maternal increased endothelial inflammation and aberrant angiogenesis. In summary, we found that preeclampsia is associated with increased inflammation, aberrant angiogenesis and activated coagulation, caused by placental factors in maternal peripheral circulation, more pronounced in the early-onset form of preeclampsia. It also appears that there is a defective modulation of the immune system in preeclamptic pregnancies. The results provide a better understanding of the pathogenesis of preeclampsia and have given suggestions to predictive markers for preeclampsia in the future.
3.
Abarenkov, Kessy, et al.
(författare)
Annotating public fungal ITS sequences from the built environment according to the MIxS-Built Environment standard – a report from a May 23-24, 2016 workshop (Gothenburg, Sweden)
2016
Ingår i: MycoKeys. - : Pensoft Publishers. - 1314-4057 .- 1314-4049. ; 16, s. 1-15
Tidskriftsartikel (refereegranskat) abstract
Recent molecular studies have identified substantial fungal diversity in indoor environments. Fungi and fungal particles have been linked to a range of potentially unwanted effects in the built environment, including asthma, decay of building materials, and food spoilage. The study of the built mycobiome is hampered by a number of constraints, one of which is the poor state of the metadata annotation of fungal DNA sequences from the built environment in public databases. In order to enable precise interrogation of such data – for example, “retrieve all fungal sequences recovered from bathrooms” – a workshop was organized at the University of Gothenburg (May 23-24, 2016) to annotate public fungal barcode (ITS) sequences according to the MIxS-Built Environment annotation standard (http://gensc.org/mixs/). The 36 participants assembled a total of 45,488 data points from the published literature, including the addition of 8,430 instances of countries of collection from a total of 83 countries, 5,801 instances of building types, and 3,876 instances of surface-air contaminants. The results were implemented in the UNITE database for molecular identification of fungi (http://unite.ut.ee) and were shared with other online resources. Data obtained from human/animal pathogenic fungi will furthermore be verified on culture based metadata for subsequent inclusion in the ISHAM-ITS database (http://its.mycologylab.org).
4.
Ursing, Johan, et al.
(författare)
High-Dose Chloroquine for Treatment of Chloroquine-Resistant Plasmodium falciparum Malaria
2016
Ingår i: Journal of Infectious Diseases. - : Oxford University Press (OUP). - 0022-1899 .- 1537-6613. ; 213:8, s. 1315-1321
Tidskriftsartikel (refereegranskat) abstract
Background. Due to development of multidrug-resistant Plasmodium falciparum new antimalarial therapies are needed. In Guinea-Bissau, routinely used triple standard-dose chloroquine remained effective for decades despite the existence of "chloroquine-resistant" P. falciparum. This study aimed to determine the in vivo efficacy of higher chloroquine concentrations against P. falciparum with resistance-conferring genotypes. Methods. Standard or double-dose chloroquine was given to 892 children aged < 15 years with uncomplicated malaria during 3 clinical trials (2001-2008) with >= 35 days follow-up. The P. falciparum resistance-conferring genotype (pfcrt 76T) and day 7 chloroquine concentrations were determined. Data were divided into age groups (< 5, 5-9, and 10-14 years) because concentrations increase with age when chloroquine is prescribed according to body weight. Results. Adequate clinical and parasitological responses were 14%, 38%, and 39% after standard-dose and 66%, 84%, and 91% after double-dose chloroquine in children aged < 5, 5-9, and 10-14 years, respectively, and infected with P. falciparum genotypes conferring chloroquine resistance (n = 195, P < .001). In parallel, median chloroquine concentrations were 471, 688, and 809 nmol/L for standard-dose and 1040, 1494, and 1585 nmol/L for double-dose chloroquine. Conclusions. Chloroquine resistance is dose dependent and can be overcome by higher, still well-tolerated doses.
5.
Eleftheriou, Nikolas M., et al.
(författare)
Compound genetically engineered mouse models of cancer reveal dual targeting of ALK1 and endoglin as a synergistic opportunity to impinge on angiogenic TGF-β signaling
2016
Ingår i: Oncotarget. - : Impact Journals, LLC. - 1949-2553. ; 7:51, s. 84314-84325
Tidskriftsartikel (refereegranskat) abstract
Angiogenesis occurs early in tumor development, sustains primary tumor growth and provides a route for metastatic escape. The TGF-β family receptors modulate angiogenesis via endothelial-cell specific pathways. Here we investigate the interaction of two such receptors, ALK1 and endoglin, in pancreatic neuroendocrine tumors (PanNET). Independently, ALK1 and endoglin deficiencies exhibited genetically divergent phenotypes, while both highly correlate to an endothelial metagene in human and mouse PanNETs. A concurrent deficiency of both receptors synergistically decreased tumor burden to a greater extent than either individual knockdown. Furthermore, the knockout of Gdf2 (BMP9), the primary ligand for ALK1 and endoglin, exhibited a mixed phenotype from each of ALK1 and endoglin deficiencies; overall primary tumor burden decreased, but hepatic metastases increased. Tumors lacking BMP9 display a hyperbranching vasculature, and an increase in vascular mesenchymal-marker expression, which may be implicit in the increase in metastases. Taken together, our work cautions against singular blockade of BMP9 and instead demonstrates the utility of dual blockade of ALK1 and endoglin as a strategy for antiangiogenic therapy in PanNET.
6.
Liu, Yan, et al.
(författare)
Dynamic niche-specific adaptations in Neisseria meningitidis during infection
2016
Ingår i: Microbes and infection. - : Elsevier BV. - 1286-4579 .- 1769-714X. ; 18:2, s. 109-117
Tidskriftsartikel (refereegranskat) abstract
Neisseria meningitidis is an opportunistic human pathogen that usually colonizes the nasopharyngeal mucosa asymptomatically. Upon invasion into the blood and central nervous system, this bacterium triggers a fulminant inflammatory reaction with the manifestations of septicemia and meningitis, causing high morbidity and mortality. To reveal the bacterial adaptations to specific and dynamic host environments, we performed a comprehensive proteomic survey of N. meningitidis isolated from the nasal mucosa, CSF and blood of a mouse disease model. We could identify 51 proteins whose expression pattern has been changed during infection, many of which have not yet been characterized. The abundance of proteins was markedly lower in the bacteria isolated from the nasal mucosa compared to the bacteria from the blood and CSF, indicating that initiating adhesion is the harshest challenge for meningococci. The high abundance of the glutamate dehydrogenase (GdhA) and Opa1800 proteins in all bacterial isolates suggests their essential role in bacterial survival in vivo. To evaluate the biological relevance of our proteomic findings, four candidate proteins from representative functional groups, such as the bacterial chaperone GroEL, IMP dehydrogenase GuaB, and membrane proteins PilQ and NMC0101, were selected and their impact on bacterial fitness was investigated by mutagenesis assays. This study provides an integrated picture of bacterial niche-specific adaptations during consecutive infection processes.
7.
Ekdahl, Kristina N., et al.
(författare)
Complement inhibition in biomaterial- and biosurface-induced thromboinflammation
2016
Ingår i: Seminars in Immunology. - : Elsevier BV. - 1044-5323 .- 1096-3618. ; 28:3, s. 268-277
Tidskriftsartikel (refereegranskat) abstract
Therapeutic medicine today includes a vast number of procedures involving the use of biomaterials, transplantation of therapeutic cells or cell clusters, as well as of solid organs. These treatment modalities are obviously of great benefit to the patient, but also present a great challenge to the innate immune system, since they involve direct exposure of non-biological materials, cells of non-hematological origin as well as endothelial cells, damaged by ischemia-perfusion in solid organs to proteins and cells in the blood. The result of such an exposure may be an inappropriate activation of the complement and contact/kallikrein systems, which produce mediators capable of triggering the platelets and PMNs and monocytes, which can ultimately result in thrombotic and inflammatory (i.e., a thrombo-inflammatory) response to the treatment modality. In this concept review, we give an overview of the mechanisms of recognition within the innate immunity system, with the aim to identify suitable points for intervention. Finally, we discuss emerging and promising techniques for surface modification of biomaterials and cells with specific inhibitors in order to diminish thromboinflammation and improve clinical outcome.
8.
Günaltay, Sezin, 1986-
(författare)
Dysregulated mucosal immune responses in microscopic colitis patients
2016
Doktorsavhandling (övrigt vetenskapligt/konstnärligt) abstract
Microscopic colitis (MC), comprising collagenous colitis (CC) and lymphocytic colitis (LC) is a common cause of chronic watery diarrhea. The diagnosis relies on typical histopathological changes observed upon microscopic examination. The studies in this thesis investigated innate and adaptive immune responses in the colonic mucosa of MC patients, also comparing patients with active disease (CC and LC) and histopathologically in remission (CC/LC-HR). We first analyzed expression of interleukin-1/Toll-like receptor (IL-1/TLR) signaling regulators in MC patients (Paper I). Our results showed enhanced IRAK-M, microRNA-146a, -155 and -21 expressions, whereas IL-37 gene expression was reduced in CC and LC patients as compared to non-inflamed controls. These results suggest different pathophysiological mechanisms in MC patients. The mixed inflammatory cell infiltrations seen in the lamina propria of MC patients might be a result of dysregulated expression of chemotactic mediators. In Paper II, we showed that MC patients display mainly an increased expression of chemokines and chemokine receptors in active disease as compared to noninflamed controls. In Paper III, we examined if the decreased IL-37 expression seen in Paper I could mediate the upregulation of chemokines seen in Paper II. We showed that a relatively small reduction in the ability of epithelial cells to produce IL-37 results in mainly increased chemokine expressions in a pattern similar to the findings in Paper II. In order to understand the nature of infiltrating T cells commonly observed in MC patients, we analyzed the T cell receptor (TCR) β chains in colonic biopsies of MC patients (Paper IV). Our results showed significant differences in TCRβ repertoire, which suggests selectively expanded T cell clones in active MC and histopathologically in remission patients. Altogether, these results i) increase the knowledge of MC pathogenesis by showing changes in TLR signaling regulators, enhanced chemokine and their receptor expressions involved in a mixed immune cell infiltrations and selectively expanded T cell clones in CC and LC patients, as well as in histopathological remission ii) might potentially increase the possibility of more target-specific therapies based on IL-37 induction, chemokines or chemokine receptor inhibitions, or hindering T cell infiltration according to TCR clonality.
9.
Hadad, Ronza, 1984-, et al.
(författare)
Protection against genital tract Chlamydia trachomatis infection following intranasal immunization with a novel recombinant MOMP VS2/4 antigen
2016
Ingår i: Acta Pathologica, Microbiologica et Immunologica Scandinavica (APMIS). - Hoboken, USA : Wiley-Blackwell. - 0903-4641 .- 1600-0463. ; 124, s. 1078-1086
Tidskriftsartikel (refereegranskat) abstract
The asymptomatic nature of most Chlamydia trachomatis infections and the lack of appropriate effects by current prevention and management call for vaccine development. We evaluated a recombinant subunit vaccine candidate based on the major outer membrane protein variable segments 2 and 4 (MOMP VS2/4). To achieve maximal immunogenicity and ease of production and purification, MOMP VS2/4 was constructed by using highly immunogenic sequences of MOMP only, thereby minimizing the presence of hydrophobic regions, and spacing the immunogenic epitopes with a flexible amino acid sequence. A purification tag was also added. The MOMP VS2/4 was given intranasally, with or without intravaginal boost, with cholera toxin (CT) adjuvant to C57BL/6 mice, which were screened for immunogenicity and protection against a live challenge infection with C. trachomatis serovar D. Bacterial shedding, cell-mediated responses, and antibody responses were monitored. Immunized mice exhibited significantly less bacterial shedding and were better protected against infertility as compared to unimmunized control mice. Immunizations stimulated both systemic and local specific antibody (IgG1, IgG2c, and IgA) responses, and primed T cells that produced interferon-c and interleukins 13 and 17 upon challenge with recall antigen. Thus, MOMP VS2/4, in combination with CT adjuvant, stimulated Th1, Th2, and Th17 effector cells, and generated protective immunity associated with less pathology. We regard MOMP VS2/4 as a promising candidate for further development into a mucosal chlamydial vaccine.
10.
Asztely, Mats, et al.
(författare)
Is ultrasonography useful for population studies on schistosomiasis mansoni? An evaluation based on a survey on a population from Kome Island, Tanzania
2016
Ingår i: Acta Radiologica Open. - : SAGE Publications. - 2058-4601. ; 5:12
Tidskriftsartikel (refereegranskat) abstract
BackgroundObservation of characteristic alterations at liver ultrasonography in clinical schistosomiasis mansoni cases has initiated utilization of this examination method in population surveys in areas where this disease is endemic.PurposeTo present results of liver ultrasonography and their relation to epidemiological data of a population in an area endemic for S. mansoni, to estimate the precision of classification of periportal anatomy changes known as periportal fibrosis (PPF), and to evaluate the relevance of ultrasonography in epidemiological studies on S. mansoni.Material and MethodsA total of 459 inhabitants on Kome Island, Lake Victoria, Tanzania were examined by ultrasound with image documentation by locally trained personnel. A subsample of this population, 116 individuals, was subject to ultrasonography by two examiners independently. Separately, the images were classified for PPF according to the Managil protocol, twice for the subsample.ResultsPPF could be classified for 458 individuals; 64% and 36% were classified as I or II, respectively; none was classified as 0; only one as III. Results were similar for the subsample examined twice. Comparing the two separate classifications of all 232 sets of images of the subsample gave a Kappa (K) value of 0.50. When comparing the classifications of each of the two different examinations of the same individuals of the subsample, K values of 0.29 and 0.34 for the first and second classification, respectively, were obtained.ConclusionUltrasonography does not appear to correlate well with disease stage. Presently, it should not be utilized for staging of schistosoma mansoni-related liver damage in population surveys.
