Thesis (Ph. D.)--University of Wisconsin--Madison, 1984. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 150-162).

Thesis (M.S.)--Youngstown State University, 1996. / Includes bibliographical references (p. 48-51).

: L’athérosclérose est une maladie inflammatoire chronique des grosses artères à localisation intimale. Elle est probablement la résultante d’une réaction inflammatoire mal contrôlée ayant pour but initial d’éliminer l’accumulation anormale de lipides au niveau de l’intima. Cette élimination est exercé par les monocytes/macrophages, dont l’infiltration et l’accumulation au niveau des lésions sont une étape cruciale de l’inflammation chronique locale provoquant en particulier la production de cytokines.Les mécanismes moléculaires responsables de cette accumulation monocytaire impliquent notamment les chimiokines et leurs récepteurs, acteurs clés de la mobilisation des leucocytes. Les souris génétiquement invalidées pour certaines chimiokines comme CCL2 et CX3CL1 ou pour leurs récepteurs respectifs sont partiellement protégées de l’athérosclérose. Par ailleurs, chez l’homme, des variations génétiques de CX3CR1 sont associées à une réduction du risque d’accidents cardiovasculaires. L’ensemble de ces résultats indiquent un rôle clé des chimiokines inflammatoires dans l’athérogenèse.L’objectif de cette thèse était de tester l’utilisation d’inhibiteurs des récepteurs de chimiokines comme outils thérapeutiques contre l’athérosclérose. Dans ce but, notre laboratoire a développé une molécule aux propriétés antagonistes du récepteur CX3CR1, marqueur utilisé pour la caractérisation phénotypique des monocytes. Nos travaux sur deux modèles murins d’athérosclérose mettent en évidence que le blocage de CX3CR1 par notre antagoniste réduit la taille des plaques d’athérosclérose formées sans modifier leur composition cellulaire ni le taux de cholestérol plasmatique circulant. Cette diminution est corrélée à une diminution du nombre d’une sous-population monocytaire circulante spécifique, ainsi qu’à une diminution de leurs propriétés d’adhérence et de survie. D’un point de vue curatif, l’antagoniste de CX3CR1 est capable de limiter la progression des plaques d’athérosclérose sans la prévenir totalement.L’utilisation d’un outil ciblant spécifiquement le récepteur CX3CR1 nous à permis d’une part de mieux comprendre le rôle de ce dernier dans les processus de monocytose et d’athérogenèse et d’autres part d’évaluer la faisabilité d’approches thérapeutiques visant à limiter le nombre de monocytes infiltrant les lésions d’athérosclérose. Les perspectives de ces travaux consistent d’une part à approfondir encore le rôle de CX3CR1 dans la mobilisation monocytaire, notamment au niveau de la moelle osseuse, et d’autre à utiliser l’antagoniste testé en association avec d’autres drogues ciblant les récepteurs de chimiokines impliqués dans l’athérogenèse, tels que CCR2 et CCR5. / Atherosclerosis account for nearly 30% of death in industrialized countries. It is a chronic inflammatory disease of the large arteries intima. It has been suggested that it is the result of an uncontrolled inflammatory reaction secondary to an abnormal accumulation of lipids in the intima. The lipid clearance is performed by monocytes / macrophages, Their infiltration and accumulation in atherosclerotic lesions is a critical step of a local chronic inflammation associated with an increased production of cytokines. The molecular mechanisms of the generation of atherosclerotic lesions involve monocytes, chemokines and their receptors which are key players controlling leukocytes mobilization. Mice genetically invalidated for chemokines such as CCL2 and/or CX3CL1 or their respective receptors are partially protected from atherosclerosis. Furthermore, in humans, genetic polymorphisms of CX3CR1 are associated with a reduced risk of cardiovascular events. Taken together, these results highlight a key role for inflammatory chemokines in atherogenesis. The aim of this thesis was to investigate wether inhibitors of chemokine receptors could play a role as therapeutic tools against atherosclerosis. To this end, our laboratory had developed an antagonist of CX3CR1, a crucial phenotypic and functional marker of monocytes. Our work, on two murine models of atherosclerosis, demonstrates that blocking CX3CR1 by our antagonist reduces the size of atherosclerotic lesions. This decrease is correlated with a lower number of circulating inflammatory monocytes, as well as a decrease in their adhesion and survival properties. Therefore, CX3CR1 antagonist coud be able to limit the progression of atherosclerotic plaques. Targeting CX3CR1 allowed us to understand the role of this receptor in the pathophysiology of atherogenesis by its effects on circulating inflammatory monocytes and to evaluate the feasibility of the use of this antagonist as a therapeutic tool to reduce atherosclerotic lesions. Perspectives of this work are firstly to deepen the role of CX3CR1 in monocyte mobilization, especially from the bone marrow, and secondly to test this antagonist in combination with others drugs targeting chemokine receptors involved in atherogenesis, such as CCR2 and CCR5 in order to better control the evolution of atherosclerotic lesions.

Thesis (M.Sc. (Medical Laboratory Sciences)) -- University of the North, 1986 / Refer to the document

published_or_final_version / abstract / toc / Botany / Master / Master of Philosophy

The ability of human monocytes to phagocytize and kill nonpiliated opaque (T3) and transparent (T4) gonococci was investigated in a tumbling tube suspension assay. A serum-sensitive strain, F62, and a serum-resistant strain, FA19, were studied. Viable colony-forming units remaining after incubation with monocytes were used to assess the extent of killing. The data show that 50% of T3 and T4 gonococci of both strains were killed by monocytes over a 2 hour period. Serum was necessary for the phagocytic killing of transparent gonococci of both strains as well as for FA19 T3. Concentrations of serum ranging from 0.5% to 10% were equally effective, and heat-labile components were required. Killing of opaque F62 T3 organisms, however, occurred in the absence of serum. Increased ratios of bacteria-to-monocytes decreased the efficiency of monocyte phagocytic killing, while a 30 minute pre-opsonization of gonococci in serum enhanced the rate of killing. Monocytes were able to kill plate grown bacteria, but not log phase organisms. A limited duration of phagocytic capability was demonstrated. The absence of lysosomal enzyme release and the Cytochalasin B inhibition of colony reduction indicated that killing was the result of intracellular bactericidal activity. Disruption of the monocytes by sonication to release internalized bacteria did not alter the number of viable colony-forming units recovered indicating that significant numbers of internalized gonococci fail to survive. Additional experiments with adherent monocyte monolayers suggested that all internalized gonococci are indeed killed immediately on ingestion. Similar results obtained from several modifications of the tumbling tube assay supported these observations. Human monocytes responded to contact by opsonized gonococci with an enhanced oxidative metabolism as measured by chemiluminescence. Non-opsonized gonococci also stimulated chemiluminescence although the magnitude of the response was 10-fold less. Both strains and types of gonococci evoked similar chemiluminescent responses which were unrelated to the extent of bactericidal activity. Inhibition of monocyte chemiluminescence by sodium azide, catalase and aminotriazole had no effect on the ability of the cells to phagocytize and kill gonococci, whereas, incubation in iodoacetic acid and phenylbutazone inhibited phagocytic killing, probably as the result of impaired phagocytosis. These data indicate that freshly isolated and in vitro cultured adherent monocytes are capable of phagocytizing and killing N. gonorrhoeae, and that the mechanism of bactericidal activity is not solely dependent on oxidative metabolism.

Thesis advisor: Kenneth C. Williams / Individuals infected with Human Immunodeficiency Virus (HIV) are susceptible to pathological abnormalities due to the infiltration of virus into different anatomical compartments. Monocytes are a heterogeneous population that undergoes changes in phenotype with HIV infection. It is hypothesized that changes in monocyte subsets observed through the course of infection will correlate with the development of SIV-Encephalitis (SIVE). 14 CD8+ T cell depleted rhesus macaques were infected with SIVmac251 and changes in 3 monocyte subsets, defined by their CD14 and CD16 surface expression as CD14+CD16-, CD14+CD16+, and CD14-CD16+, were tracked through the course of disease. The CD14+CD16- subset increased in the absolute number of cells and decreased in percentage of the total monocyte population. The CD14+CD16+ and CD14-CD16+ subsets increased in both absolute number and percentage. These changes have a biphasic dynamic that occurs during early infection and is pronounced in encephalitic animals. Several markers showed differential expression with infection and between subsets. Mac387, an early monocyte-macrophage marker, demonstrated a considerable decrease in expression. Concomitant with this change, CD68, CD163, CD44v6, CCR2, and CD64 increased expression in the total monocyte population, with the magnitude of these changes occurring in a subset-specific manner. In conclusion, monocyte subsets undergo changes with SIV infection that correspond to the development of encephalitis, highlighting the contribution of monocytes in neuroAIDS. / Thesis (MS) — Boston College, 2010. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Biology.

Thesis advisor: Kenneth Williams / Proliferating cell nuclear antigen (PCNA) is a DNA polymerase δ auxiliary protein during cell cycle. However, PCNA is also present in quiescent cells undergoing DNA repair. This study investigates the expression of PCNA in CNS macrophages of SIV infected Rhesus macaque and examines the presence of PCNA in monocytes prior to differentiation into CNS macrophages. Accumulation of macrophages in the SIV infected brain, together with the creation of multinucleated giant cells (MNGC), form SIV lesions, which lead to neurological disorders. From the twelve animals used in this study, four were analyzed by flow cytometry to detect PCNA expression in monocytes, but no expression of PCNA was detected. Peripheral blood mononuclear cells (PBMC) of five animals were also analyzed using cytospin preparations to confirm results obtained by flow cytometry. The study did not find induction of PCNA mRNA by qRT-PCR in infected animals. Animals that developed SIVE were analyzed by immunohistochemistry to identify PCNA in recently immigrated macrophages. Together results suggest that 1) PCNA is not expressed in monocytes; 2) PCNA in monocyte/macrophages is induced in SIV infected animals and it is not associated with cell cycle; 3) Recently immigrated monocytes of CNS are PCNA negative and 4) majority PCNA+ macrophages in the SIVE lesions are perivascular macrophages. / Thesis (MS) — Boston College, 2010. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Biology.

Monocytes and their subsets play an important role in immune and inflammatory diseases. In this study the focus was on their role of driving pathogenesis in asthmatic patients. The hypothesis was that although monocytes have not been identified as key players in atopic disease they are likely to be pro-inflammatory, be readily recruited to tissue and have a major role in the exacerbation of disease. This may relate to the prevailing pro-inflammatory microenvironment. Chemokines such as CCL2 and CX3CL1 are involved in monocyte recruitment and survival respectively in the inflamed tissues. Three subsets of monocytes namely CD14++CD16-, CD14++CD16+ and CD14+CD16++ monocytes are known to express chemokine receptors. Alterations if any in the numbers or in the molecular inflammatory markers of these three monocyte subsets with contrasting potential of modulating inflammatory responses in the peripheral blood may provide some insight in the disease process. It is also believed that circulating fibrocytes in allergic asthma are the cause of fibrosis in chronically inflamed pulmonary tissues resulting in refractory asthma. Fibrocytes, also derived from the bone marrow, produce connective tissue components such a collagen-1 and can adopt a mesenchymal phenotype and contribute to granulomas, scar tissue and tissue remodeling. They appear to play an important role in chronic and refractory asthma but have also been found in lungs of patients with mild asthma indicating that they may play an as yet undefined role in the development of inflammation. Fibrocytes also express chemokine receptors and their recruitment in tissues may also depend upon chemokines. Using six-color flow-cytometry phenotypic analysis of human blood monocyte and fibrocyte populations from asthma patients was performed along with the isolation of mRNA from CD14+ monocytes for assessment of inflammatory markers expression and the data was compared with the normal healthy individuals. Based on the findings of gene expression an attempt was made to demonstrate the effect of routine treatment used by our patients on gene expression of selectively isolated monocytes from healthy individuals. Finally serum levels of chemokines between patients and normal healthy controls were also determined. XXI From the flow-cytometry analysis we demonstrated a significant increase in both CD45-positive monocytes and circulating fibrocytes in severe asthmatic patients. While CCR2 percentage was significantly increased, the CX3CR1 percentage was significantly decreased in the intermediate and non-classical monocyte subsets in both mild and moderate patients, however these changes were only observed in the non-classical monocytes in severe patients. In the gene expression the proinflammatory receptors CCR2, CCR5, CX3CR1, IL-17RA, and cytokine inhibitor SOCS3 in monocytes were all significantly reduced in the severe asthma patients. While CCR1 and CD36 were significantly decreased in mild and moderate asthmatic patients. No significant change in serum pro-inflammatory cytokines were detected although IL-5 was significantly increased in moderate and severe asthmatic patients. Analysis of monocyte gene expression in asthma by other groups although not highlighting a specific gene did indicate that inflammatory and TNF pathways might be involved. In conclusion there was a tendency toward more inflammatory monocytes in our asthma patients, however this was not clearly reflected in the patients serum profile given that inflamatory monocytes make up only a small percentage of the leukocytes in human blood. Finally increases in total monocytes and fibrocytes correlated with asthma severity.

Les monocytes sont des leucocytes circulants dont la caractérisation est longtemps restée difficile. La dissection de l’ensemble de ces cellules en sous-populations fonctionnelles chez l’homme reste à ce jour insuffisante. Les monocytes sont cependant des précurseurs circulants de plusieurs populations de cellules dendritiques et de macrophages tissulaires, et occupent donc à ce titre une place prépondérante dans la mise en place des réponses immunitaires normales et pathologiques.À l'heure actuelle, trois sous-populations sont décrites chez l’homme : les monocytes classiques CD14+CD16neg, les non-classiques CD14dimCD16+ et les intermédiaires CD14+CD16+. Fonctionnellement, ces sous-populations sont diverses et hétérogènes et dotées de propriétés pro- et anti-inflammatoires apparemment redondantes. En pathologie, une augmentation du ratio entre CD16+ et CD16neg monocytes a été décrite en situation inflammatoire, suggérant un rôle des premières dans le développement et/ou l’amplification de l’inflammation. Parmi les monocytes non-classiques, des cellules capables de détecter des altérations de l’endothélium et ayant donc des propriétés spécifiques de surveillance du lit vasculaire ont été identifiées et caractérisées. Dans le but d’obtenir une meilleure définition des populations monocytaires et de les subdiviser en sous-populations où l’identification des fonctions de ces cellules serait plus accessible, je me suis attachée, dans ce travail de thèse, à analyser les différentes populations de monocytes humains circulants de manière aussi exhaustive que possible et avec les outils d’analyse biologiques et informatiques actuels. Les résultats, obtenus par l’analyse en cytométrie de flux de PBMC de 28 donneurs sains après marquage des cellules par vingt anticorps dirigés contre les molécules de surface, ont révélé l’existence d’une population de monocytes de plus grande taille. Ces « large » monocytes se subdivisent également en populations CD16neg et CD16+ (monocytes la14+16neg et la14+16+). Les monocytes restant ou « small » se composent de sm14+16neg largement majoritaires, de sm14+16+, et de sm14dim16+ auxquels se rajoutent des monocytes sm14lo16neg dont nous confirmons l’existence. L’expression des divers marqueurs sélectionnés a été faite par des méthodes d’analyse classiques, manuelles, ainsi que par l’utilisation d’algorithmes d’analyse non-supervisée. Les résultats ont montré les particularités d’expression propres à chaque population mais ont aussi indiqué que l’hétérogénéité phénotypique à l’intérieur de ces six populations de monocytes reste importante. Cependant, des profils d’expression qui sont partagés par plusieurs donneurs sains ont été identifiés. L’expression des molécules d’adhésion telles que CD49d, CD62L, CD162, ainsi que CD43 a été particulièrement utile pour cette identification. Quatre groupes phénotypiques majeurs ont ainsi été définis chez les 28 donneurs sains analysés. / Monocytes are circulating leukocytes which characterization has long been difficult. Dissection of these cells into functional subpopulations in humans is still insufficient. Monocytes are however circulating precursors of several populations of dendritic cells and tissue macrophages, and play a prominent role in the development of immune response in steady state and pathology. At present, three monocyte subpopulations are described in humans: classical CD14+CD16neg, non-classical CD14dimCD16+ and intermediates CD14++CD16. Functionally, these subpopulations are diverse and heterogeneous and with apparently redundant pro - and anti-inflammatory properties. In pathology, an increase in the ratio of CD16 + to CD16neg monocytes has been described in inflammatory situation, suggesting a role of the former in the development and amplification of inflammation. Among the non-classical monocytes, cells that can detect changes in the endothelium and having then specific properties of vascular bed monitoring have been identified and characterized. In order to get a better definition of monocyte populations and break them down into subpopulations in which the identification of the cell functions would be more accessible, I endeavoured in this thesis work to analyse different populations of circulating human monocytes as comprehensively as possible and with state of the art analytical and computer tools. The results of flow cytometry analysis of PBMC from 28 healthy donors after cell staining with twenty antibodies directed against surface molecules revealed the existence of a population of monocytes of larger size.