Thesis (Ph. D.)--University of Alabama at Birmingham, 2007. / Title from first page of PDF file (viewed Oct. 13, 2008). Includes bibliographical references.

The aim of this thesis was to investigate the possible role of neutrophil granulocytes in antitumor reactions. Most of our experiments were focused on in vitro studies assessing the cytotoxic effect of mouse neutrophils on B16-F10 melanoma cells labelled with PAMPs. We put an emphasis on activation and generating a prime state of neutrophils. Moreover, a release rate of enzyme myeloperoxidase from azurophil granules was detected as a marker of neutrophil degranulation. We also attempted to attract neutrophils into tumor microenvironment using thioglycolate medium and its main compound casein.

Camundongos AIRmax e AIRmin exibem diferenças significativas no número médio de leucócitos migrantes ao exudato inflamatório produzido por partículas de poliacrilamida. Um dos fatores preponderantes para a maior capacidade inflamatória da linhagem AIRmax é a maior produção de neutrófilos maduros pela medula óssea. No presente estudo avaliamos os fatores celulares e moleculares que conferem diferente potencial hematopoético entre as linhagens AIRmax e AIRmin e a associação destes com a intensidade da resposta inflamatória aguda (AIR). Nossos resultados demonstraram que apenas os animais AIRmax desenvolvem uma mielopoese emergencial induzida pelo Biogel com expansão de progenitores mielóides e produção de citocinas nas primeiras horas da inflamação. Desta forma, concluímos que a capacidade dos animais AIRmax de desenvolver uma alta AIR, em relação aos animais AIRmin, esta associada com o potencial de expansão das células progenitoras mielóides, que por sua vez, pode ser determinada pelos fatores solúveis locais produzidos nas primeiras horas da inflamação. / AIRmax and AIRmin exhibit significant differences in the average number of migrant leukocytes and protein content of the inflammatory exudate produced by polyacrylamide beads. One of the most important factors for the inflammatory capacity of AIRmax is the higher production of mature neutrophils by the bone marrow. In the present study we aimed to evaluate the cellular and molecular factors that confer different hematopoietic capacity between AIRmax and AIRmin and the association of these factors with the intensity of the acute inflammatory response (AIR). Our results showed that only animals AIRmax are able to develop an emergency myelopoiesis induced by Biogel presenting expansion of myeloid progenitors and cytokine production in the early hours of inflammation. Thus, we conclude that the ability of the AIRmax mice for developing a high AIR, compared to AIRmin mice, it is associated with the potential of expansion of myeloid progenitor cells, which in turn might be determined by the local soluble factors produced during the first hours of inflammation.

Malignant lymphomas are a group of cancerous diseases that develop from lymphocytes and primarily affect lymph nodes. Being the sixth most common cancer type in Sweden, lymphoma is a societal problem that needs to be tackled by improving care and treatment of patients. This study was designed to examine the blood cell composition in lymphoma patients and well as determine whether the use of cryopreserved cells affected the analysis outcome. An evaluation of the methods used was also performed. Frozen peripheral blood from lymphoma patients as well as fresh and frozen blood from healthy controls was used. The cells of interest were monocytes, granulocytes, Treg, NKT, iNKT, B and T cells plus the dendritic cell activation protein CCR7. Three immunophenotyping methods were used. Method one was used in staining surface cell markers while the other two were for both surface and intracellular staining using two distinctive kits. The results showed no significant difference in immune cell composition between patients and blood donors. Limited patient samples and the lack of female blood donors could explain the unexpected result. A substantial difference in Treg cells was observed in fresh and frozen tested samples as well as T cell outcomes in method one compared to the other two methods. There were fewer Treg cells in frozen samples, which probably was due to cryopreservation while the lack of fixation in method one led to the loss of CD4+ T cells. Overall, the methods used were adequate but definitely require some improvements.

Le tissu adipeux (TA) est connu pour sa plasticité puisqu'il est capable de s'hypertrophier ou de s'atrophier, en fonction de la situation métabolique de l'individu. Cette plasticité est liée au fait que le TA joue un double rôle dans le maintien de la balance énergétique : il est à la fois i) réserve d'énergie mobilisable (adipocytes blancs) mais également ii) consommateur d'énergie via la thermogénèse (adipocytes bruns, adipocytes beiges). En raison de l'évolution croissante des maladies métaboliques dites de surcharge dans lesquelles ce TA va s'hypertrophier, la majorité des études abordent cette notion de plasticité à l'échelle cellulaire, et se focalise ainsi sur les adipocytes (prolifération, différenciation, activité) et les autres populations cellulaires résidant dans le TA, capables d'interagir avec eux. En revanche, il y a très peu d'études sur cette plasticité à l'échelle tissulaire. Au cours de ma thèse, je me suis intéressée i) à l'organisation tissulaire d'un dépôt de TA blanc (dépôt sous-cutané inguinal) et ii) les conséquences d'une ablation massive du TA blanc. L'ensemble de ce travail a été réalisé chez la souris.A l'aide de l'imagerie 3D sur tissu entier, nous montrons que ce dépôt est hétérogène : il est composé d'une partie dans laquelle il est possible de segmenter des entités fonctionnelles (lobules ?), située au cœur du dépôt, et d'une partie non segmentable, située à la périphérie du dépôt. Cette hétérogénéité structurale est associée à une hétérogénéité fonctionnelle : les deux régions se distinguent en termes de morphologie adipocytaire et de pattern d'expression génique. De plus, seule la partie segmentable répond à la mise au froid des animaux par une up-régulation du niveau d'expression d'Ucp1 et d'autres gènes marqueurs du " brunissement ". Parallèlement à cela, nous montrons que selon la souche de souris (C57bl6 et MRL), la réponse du TA inguinal à une ablation partielle n'est pas la même : chez la souris MRL (rare mammifère capable de régénération), ce dépôt adipeux est capable de régénérer, ce qui n'est pas le cas chez la souris C57Bl/6. La régénération est inhibée chez la souris MRL par un traitement avec un agoniste des récepteurs aux opioïdes (tramadol) alors qu'elle peut être induite chez la souris C57Bl/6 par un antagoniste de ces récepteurs (naloxone). Cette régénération est dépendante d'une forte et intense production d'espèces actives de l'oxygène par les granulocytes. L'utilisation de souris invalidées pour le récepteur mu démontre l'implication de cette sous-famille de récepteurs. Enfin, cet effet des opioïdes est majoritairement le fait des cellules immunitaires, et plus particulièrement les granulocytes. Ces données mettent en exergue une nouvelle vision du TA blanc sous - cutané, qui ne doit pas être considéré comme un tissu inerte mais bel et bien comme un tissu hétérogène complexe (structurellement et fonctionnellement) pouvant être capable de régénération. / Adipose tissue (AT) is very plastic tissue. During metabolic disease, it would be overdeveloped or atrophy. It is due to the fact that AT is i) energy storage thanks to white adipocyte and ii) energy consumer thanks to brown or brite adipocyte. The cellular composition is very well studied (adipocytes activity, proliferation, differenciation, link between AT stromal cells / adipocytes) but the tissue organization of AT is not known. During my thesis work, we study the i) tissular organization of white AT and ii) AT response after massive removal of white AT. Mice are used for this work. In the first step, our 3 dimensional imaging of white AT shows that AT is heterogeneous tissue: AT has 2 components: segmentable area, in the AT core and non-segmentable area, in the AT periphery. This structural heterogeneity is correlated with functional heterogeneity because segementable area differs to non-segmentable area from adipocyte shape and pattern genic expression. Furthermore, only segmentable area can be respond to cold exposure by Ucp1 up-regulation and browning genes markers. In the second step, massive ablation of subcutaneous white AT is performed on two mice strains: C57Bl/6 and MRL (known to be able to regenerate). MRL mice inguinal AT regenerate, unlike inguinal AT of C57Bl/6 mice. The use of antagonist of opioid receptor (naloxone) treatment leads regeneration AT in C57Bl/6. In opposite, opioid receptor agonist (tramadol) treatment in MRL mice inhibits AT regeneration. AT regeneration is dependant of burst oxydatif production by granulocytes. The use of the receptor knock down mice highlights that is the only receptor is involved in AT regeneration. More precisely, opioids effects are mediated by receptor on granulocyte immune cells.

Les granulocytes de faible densité (LDGs) sont un sous-type de neutrophiles mis en évidence initialement dans le sang de patients atteints de différentes maladies telles que le lupus érythémateux systémique ou le psoriasis. Cependant, des études rapportent également leur présence chez des individus sains. On connait mal à ce jour les caractéristiques des LDGs, notamment en ce qui a trait à leur profil inflammatoire. De plus, leur biogenèse demeure toujours mal connue. Mes travaux de maîtrise visaient à comparer les propriétés des LDGs à celles des neutrophiles de densité normale (NDNs). Pour ce faire, 8 chevaux atteints d’asthme équin sévère et 11 chevaux sains bien caractérisés ont été sélectionnés pour l’étude et sur lesquels des isolations de NDNs ainsi que des LDGs ont été réalisées. La morphologie des neutrophiles a ensuite été évaluée par microscopie optique. Le contenu en myéloperoxidase, un composant des granules primaires azurophiles des neutrophiles, et la présence de récepteurs du N-formylméthionine-leucyl-phénylalanine (fMLP-R) ont été évalués par cytométrie de flux et immunofluorescence, respectivement. Enfin, la capacité fonctionnelle de ces cellules à produire spontanément des pièges extracellulaires des neutrophiles (NETs) a été étudiée in vitro par microscopie confocale. Les résultats démontrent que le nombre de LDGs est augmenté dans le sang des chevaux asthmatiques lors d'exacerbation de la maladie. De plus, ces cellules présentent une morphologie différente puisqu’elles sont de taille plus petite et contiennent plus de fMLP-R que les NDNs. Le contenu en myéloperoxidase est cependant similaire dans les deux populations de neutrophiles. Enfin, les LDGs produisent plus de NETs, et sont plus sensibles aux stimuli activateurs que les NDNs. Ces caractéristiques sont similaires dans les 2 groupes de chevaux suggérant ainsi que ce sont des propriétés intrinsèques des LDGs et qu’ils représentent une population cellulaire préactivée et qui de plus, est majoritairement mature. Cette étude caractérise et compare pour la première fois les LDGs chez des animaux sains et ceux retrouvés chez des animaux atteints d’une maladie inflammatoire chronique. / Low-density granulocytes (LDGs) are a subset of neutrophils first described in the bloodstream upon pathological conditions. However, several studies also reported the presence of these cells in the blood of healthy patients. Whether LDGs characteristics, especially their enhanced pro-inflammatory profile, are specific to this subset of neutrophils and not related to disease states is unknown. Thus, we sought to compare the properties of LDGs to those of autologous normal-density neutrophils (NDNs), in both health and disease. We studied 8 horses with severe equine asthma and 11 healthy animals. Neutrophil morphology was studied using optical microscopy, and content in myeloperoxidase and N-formylmethionine-leucyl-phenylalanine receptors (fMLP-R) evaluated using flow cytometry and immunofluorescence, respectively. Confocal microscopy was used to determine their functional capacity to spontaneously release neutrophil extracellular traps (NETs) stimulating with phorbol-12-myristate-13-acetate (PMA). LDGs were smaller and contained more fMLP-R than NDNs, but myeloperoxidase content was similar in both populations of neutrophils. They also had an increased capacity to produce NETs, and were more sensitive to activation stimuli. These characteristics were similar in both healthy and diseased horses, suggesting that these are intrinsic properties of LDGs. Furthermore, these results suggest that LDGs represent a population of primed and predominantly mature cells. Our study is the first to characterize LDGs in health, and to compare their characteristics with those of animals with a naturally occurring disease.

O Fator estimulador de colônias de granulócitos humano recombinante (rhG-CSF) produzido em Escherichia coli é uma proteína não glicosilada com 175 aminoácidos, de grande importância clínica para o tratamento de neutropenias. O presente trabalho propõe a construção de dois sistemas de expressão em E. coli, um sistema para obtenção do rhG-CSF no citoplasma e outro para secreção da proteína recombinante no meio de cultura utilizando a sequência sinal da L-asparaginase II. Os dois sistemas de expressão foram testados e comparados. A partir desses dados, passou-se para as etapas de obtenção do rhG-CSF com o sistema de expressão sem a sequência sinal. As etapas de renaturação e purificação foram eficientes obtendo-se uma proteína com adequado grau de pureza, integridade estrutural e atividade biológica. Essa proteína também foi utilizada com sucesso para a produção de anticorpos policlonais em camundongos. Com os resultados obtidos, a proteína rhG-CSF mostrou-se viável para estudos posteriores em bioreatores e produção em escala-piloto. / The recombinant human granulocyte colony stimulating factor (rhG-CSF) is a non-glycosylated protein with 175 amino acids. This factor plays an important role in hematopoietic cell proliferation and has been widely used for treating neutropenia. The purpose of this work is to construct two expression systems in E. coli; a system for obtaining rhG-CSF in the cytoplasm and the other for secretion of recombinant protein in the culture medium using the signal sequence of L-asparaginase II. The two expression systems were tested and compared. From these data, the next steps for obtaining the rhG-CSF were done with the expression system without the signal sequence. The refolding and purification steps were efficient, resulting in a protein with adequate purity, structural integrity and biological activity. This protein has also been successfully used for the production of polyclonal antibodies in mice. With these results, the protein rhG-CSF was feasible for further studies in bioreactors and pilot scale production.

O Fator estimulador de colônias de granulócitos humano recombinante (rhG-CSF) produzido em Escherichia coli é uma proteína não glicosilada com 175 aminoácidos, de grande importância clínica para o tratamento de neutropenias. O presente trabalho propõe a construção de dois sistemas de expressão em E. coli, um sistema para obtenção do rhG-CSF no citoplasma e outro para secreção da proteína recombinante no meio de cultura utilizando a sequência sinal da L-asparaginase II. Os dois sistemas de expressão foram testados e comparados. A partir desses dados, passou-se para as etapas de obtenção do rhG-CSF com o sistema de expressão sem a sequência sinal. As etapas de renaturação e purificação foram eficientes obtendo-se uma proteína com adequado grau de pureza, integridade estrutural e atividade biológica. Essa proteína também foi utilizada com sucesso para a produção de anticorpos policlonais em camundongos. Com os resultados obtidos, a proteína rhG-CSF mostrou-se viável para estudos posteriores em bioreatores e produção em escala-piloto. / The recombinant human granulocyte colony stimulating factor (rhG-CSF) is a non-glycosylated protein with 175 amino acids. This factor plays an important role in hematopoietic cell proliferation and has been widely used for treating neutropenia. The purpose of this work is to construct two expression systems in E. coli; a system for obtaining rhG-CSF in the cytoplasm and the other for secretion of recombinant protein in the culture medium using the signal sequence of L-asparaginase II. The two expression systems were tested and compared. From these data, the next steps for obtaining the rhG-CSF were done with the expression system without the signal sequence. The refolding and purification steps were efficient, resulting in a protein with adequate purity, structural integrity and biological activity. This protein has also been successfully used for the production of polyclonal antibodies in mice. With these results, the protein rhG-CSF was feasible for further studies in bioreactors and pilot scale production.

A la phase aiguë des accidents vasculaires cérébraux, les stratégies thérapeutiques reposent sur l'utilisation d'agents fibrinolytiques dont l'utilisation est limitée par une fenêtre thérapeutique étroite en raison du risque d'hémorragies intra-cérébrales lié à des altérations vasculaires et parenchymateuses. Cette approche fibrinolytique nécessiterait d'être complétée par une double protection de la paroi vasculaire et du parenchyme cérébral. Au sein de l'unité neurovasculaire, les leucocytes, et particulièrement les polynucléaires neutrophiles, jouent un rôle important dans l'inflammation, tant vasculaire que parenchymateuse qui conduit aux lésions cérébrales.<br />Ce travail a pour objectif de déterminer si dans un modèle d'ischémie cérébrale la modulation des interactions leucocytes-endothélium pourrait représenter une cible pertinente : (i) pour diminuer les conséquences lésionnelles de l'ischémie ; (ii) limiter le risque de complications hémorragiques de la thrombolyse. Ceci s'est fait par une double approche pharmacologique : (i) une modulation directe des polynucléaires neutrophiles ; (ii) une modulation des interactions par l'activation des récepteurs nucléaires PPAR-alpha.<br />Dans un premier temps, nos résultats suggèrent une contribution importante des leucocytes dans les altérations vasculaires post-ischémiques ainsi que dans la survenue des complications hémorragiques induites par la fibrinolyse. Dans la deuxième partie de notre travail, l'activation des récepteurs nucléaires PPAR-alpha prévient les altérations endothéliales vasculaires post-ischémiques parallèlement à un effet neuroprotecteur. Ces effets étaient associés à une diminution des complications hémorragiques et du recrutement leucocytaire au sein du foyer ischémique.<br />En conclusion, la protection neurovasculaire après une ischémie cérébrale suivie ou non d'une fibrinolyse apparaît comme une cible intéressante susceptible de prévenir la maturation de l'ischémie cérébrale et les complications hémorragiques. Les récepteurs nucléaires PPAR-alpha représentent expérimentalement une stratégie thérapeutique potentielle de protection de la paroi vasculaire et du tissu cérébral en modulant les interactions leucocytes-endothélium

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2001. / Härtill 5 uppsatser.