<p>Lung cancer is the leading cause of cancer related deaths in both the US and Canada and efforts still need to be made towards understanding the disease. The role of inflammation in the promotion of cancer development represents a newer avenue of research. The glycoprotein (gp)-130 cytokine interleukin-6 (IL-6) has a well established role in promoting inflammation and recent evidence suggests roles in development of certain tumors in animal models. Less is known of the related family member oncostatin M (OSM) and the functions of either IL-6 or OSM in lung cancer development is not known. Based on the hypothesis that these cytokines promote lung cancer development, IL-6 and OSM were overexpressed in the lungs of two separate mouse models for lung cancer utilizing adenovirus vectors encoding IL-6 or OSM. The first mouse model utilized a Cre-conditional oncogene KRAS G12D (developed by Tyler Jacks) in which endotracheal administration of adenovirus (Ad)-encoded Cre-recombinase resulted in increases in lung densities in a dose-dependent fashion over a period of 6 weeks that were measurable by CT scanning and histology. Increases in cytokines IL-6 and kertinocyte chemoattractant (KC) were detectable in the bronchoalveolar lavage (BAL) by week 4, as well as marked increases in alveolar macrophage numbers. Macrophages were also shown as a possible target for Cre-mediated recombination and mutant KRAS expression. Administration of either AdIL-6 or AdOSM as well as AdCre resulted in a trend toward increases in tumor burden with AdOSM based on experiments terminated at 4 weeks. The second mouse model involved endotracheal administration of the lewis lung carcinoma (LLC) cell line, which after 7 days resulted in detectable tumor burden. Administration of either AdIL-6 or AdOSM and LLC cells simultaneously was shown to increase tumor burden relative to AdDl70 co-administration. These results suggest a possible role of IL-6 or OSM in promoting lung tumor development in animal models and may ultimately reveal gp130 cytokines IL-6 or OSM as a possible therapeutic target for the treatment of lung cancer.</p> / Master of Science (MSc)

The immune system has been suggested as crucial in brain and psychological functioning. More precisely, immune markers reflecting immune system activity are important for psychological and mental health, as evident by their role in the physiopathology of depression and in the impairment of executive functions. Frontal alpha asymmetry (FAA), an electroencephalographic marker of brain function, has also been linked to such psychopathology and is thought to reflect psychological processes underlying approach- versus withdrawal-related motivation and higher-order inhibitory control. Only a few studies have linked FAA to immune markers but notably found a negative association between IL-6, a pleiotropic proinflammatory cytokine, and FAA. The aim of the present work is thus to study the relationship between various immune markers (including pro-inflammatory cytokines and IL-6) and FAA. 35 healthy young male participants underwent a resting EEG recording and blood sampling from which immune markers were measured. The results did not suggest an association between IL-6 and FAA. No other immune markers were either suggested to be associated to FAA. The complexity of the immune system (e.g., effect of cytokines) is underlined and may explain the results. Despite such results, the implication of true negative correlations between FAA and circulating immune markers, as suggested in previous studies, is discussed in the light of the theoretical models of FAA.

Thesis (MSc (Physiological Sciences))--University of Stellenbosch, 2011. / Includes bibliography. / ENGLISH ABSTRACT: Background: IL-6 belongs to a cytokine super-family known to affect cell proliferation, although other family members are better characterized. Proliferation promoting factors (IL-6) compete with differentiation promoting factors (myogenic regulatory factors: MyoD and myogenin) to affect cell cycle. Cell cycle progression is assessed by determining the proportion of cells shifting from arrest to chromatin synthesis and mitosis phases (G0/G1 and S and G2/M respectively). Methods: This study assessed the effects of IL-6 on cell cycle progression and proliferation vs. differentiation of C2C12 skeletal myoblasts. Physiological doses (10 or 100 pg/ml) were compared to a high dose (10 ng/ml), with exposure lasting 48 hours (addition of IL-6 dose to proliferation medium at 0 and 24 hours). Acute signaling downstream of the IL-6 gp130 receptor was assessed after the first exposure. Results: Propidium iodide analysis of nuclear material using flow cytometry indicated shifts in forward scatter. Both Low and Medium doses shifted a greater proportion (p<0.05) of cells from G0/G1 to S and G2M phases at 24 hours and all doses resulted in the same shift (p<0.05) at the 48 hour time point. However, the High dose significantly (p<0.05) increased myogenin expression at the 48 hour time point. Microscopy indicated that confluence was prevented by low seeding density and did not influence the result. Cells harvested at 5 minutes post stimulation indicated that all doses significantly increased STAT3 phosphorylation. 10 minutes post stimulation the High dose group sustained elevated levels of STAT3 phosphorylation. Conclusions: Low and medium doses of IL-6 increase proliferation in a muscle satellite cell line by activating cell division and allowing myoblasts to remain in the active cell cycle. High doses of IL-6 increase differentiation by mediating upregulation of myogenic regulatory factors and this is thought to be due to prolonged STAT3 activation. Physiological control of myoblast behaviour by cytokines is evident and such control would be influenced by the severity of the endogenous cytokine response to various stimuli. / AFRIKAANSE OPSOMMING: Agtergrond: IL-6 behoort aan n sitokien super-familie bekend vir die affektering van sel verspreiding, alhoewel ander familie lede beter gekenmerk is. Bevordering van verspreiding faktore (IL-6) kompeteer met bevordering van differensiasie fatore (myogenic regulatory factors: MyoD en myogenin) om die sel siklus te affekteer. Sel siklus progressie word geassesseer deur die bepaling van die proporsie selle wat verskuif van arrestasie na chromatien sintese en mitose fases (G0/G1 en S en G2/M onderskeidelik). Metodes: Hierdie studie het die effekte van IL-6 op die progressie van die sel siklus geassesseer asook die proliferasie vs. differensiasie van C2C12 skelet spier satelliet selle. Fisiologiese dosisse (10 en 100 pg/ml) was vergelyk tot n hoog dose (10 ng/ml), met blywende blootstelling van 48 uur (byvoeging van IL-6 dose tot verspreidings medium op 0 and 24 uur). Akute sein stroomaf van die IL-6 gp130 reseptor was ook geassesseer na die eerste blootstelling. Resultate: Propidium iodide analise van kern materiaal deur vloei sitometrie het voorwaarts verskuiwing aangedui. Beide Laag and Medium doses het n groter proporsie (p<0.05) selle verskuif van die G0/G1 tot die S en G2M fases na 24 uur en alle dosisse het gelei in die selfde verskuiwing (p<0.05) by die 48 huur tyd punt. Alhoewel die Hoog dose myogenin uitdrukking aansienlik (p<0.05) verhoog het na 48 uur. Mikroskopie het aangedui dat samevloeiing voorkom was deur n lae loting digtheid en dit het nie resultate geaffekteer nie. Selle wat geoes was 5 minute na stimulasie het aangedui dat alle dosisse STAT3 fosforilasie laat toeneem het. 10 minute na stimulasie het die Hoog dose groep volgehoue vlakke van STAT3 fosforilasie besit. Gevolgtrekkings: Laag en Medium dosisse van IL-6 verhoog verspreiding in n spier satelliet sel lyn deur die aktivering van sel deling en deur selle toe te laat om in die aktiewe sel siklus te bly. Hoog dosisse van IL-6 verhoog differensiase deur bemiddelende opstoot van myogenic regulatory factors en die gedagte is dat dit bewerkstellig word deur aanhoudende aktivering van STAT3. Fisiologies beheer van satelliet selle deur sitokiene is duidelik en die beheer sal beinvloed word deur die erns van die endogene sitokien reaksie op verskillende stimuli.

Thesis (MSc (Physiological Sciences))--University of Stellenbosch, 2011. / Includes bibliography. / ENGLISH ABSTRACT: The hypothalamic-pituitary-adrenal-(HPA) axis has long been closely associated with psychological stress-induced activation of the adrenal cortex and subsequent glucocorticoid production. Another, less known peripheral limb of the psychological stress response, is the sympatho adrenal medullary pathway. We hypothesized that the sympatho-adrenal medullary system constitutes the primary response to acute psychological stress, with the HPA-axis functioning as a secondary response. We tested our hypothesis by manipulating a model of acute mild psychological stress (restraint) by blocking IL-6, a valuable constituent of the sympatho-adrenal medullary system. Serum corticosterone concentration increased in response to stress (7 ± 3 vs. 57 ± 4 ng/ml; P<0.0001), a response attenuated when IL-6 was blocked (17 ± 7 ng/ml). Stress increased pituitary mass only when IL-6 was blocked (38 ± 3 vs. 65 ± 6 mg; P <0.001). Stress increased left adrenal mass only in the presence of IL-6 (34 ± 1 vs. 73 ± 8 mg; P <0.00001). Stress did not influence the circulating levels of TNF-α, IL-1β or IL-6 significantly. IL-1β and TNF-α concentrations in the unstressed rats were lower when IL-6 was blocked. We then manipulated the stress model by administering S. frutescens extract to elucidate both the central and peripheral effects of acute S. frutescens administration on the psychological stress response. Restraint caused decreases in hippocampal GR levels when compared to respective controls. S. frutescens administration and exposure to restraint synergistically decreased hippocampal GABAAR levels. In addition, exposure to both stress and S. frutescens led to a noteworthy increase in pituitary mass (P = 0.078), as well as pituitary ACTH levels (P < 0.01). Similarly, differences in circulating ACTH levels showed an effect of stress on ACTH secretion only in the presence S. frutescens (P < 0.05). Adrenal mass was significantly increased in S. frutescenstreated animals that were also exposed to restraint (P < 0.05). Adrenal levels of ACTH showed a reciprocal trend to pituitary and circulating ACTH levels. No statistically significant differences were seen in adrenal IL-6 content. However, marked increases in IL-6 levels were seen at this level with administration of S. frutescens stress exposure and a cumulative increase seen with both S. frutescens-treatment and stress exposure. Hippocampal GABAAR, pituitary mass, pituitary ACTH and circulating ACTH levels showed a similar trend towards a synergistic effect of S. frutescens and restraint in activation of the psychological stress response, while adrenal ACTH levels showed an inverse trend. Hippocampal GR did not show any effect of stress or S. frutescens-treatment. The results from these two experiments indicate that the sympatho-adrenal medullary system constitutes the primary response to acute mild psychological stress and that the HPA-axis is only activated during an exacerbated stress response or when the sympatho-adrenal medullary contribution is inadequate. Furthermore, the acute administration of S. frutescens possibly led to a functional shift in GABAergic function, resulting in activation of the stress response. The anecdotal reports of a “docile” effect of S. frutescens most likely results from activation of the mesolimbic dopaminergic system by the hippocampus and amygdala. These results have dramatic consequence in GABA-based anxiety-treatments. / AFRIKAANSE OPSOMMING: Die hipotalamo-pituïtêre-adrenale (HPA)-as is lank bekend as ‘n primêre rolspeler in die respons op emosionele stres en daaropvolgende glukokortikoïed produksie. ‘n Ander, minder bekende arm van die sielkundige stres respons is die simpatiese bynier-medulla-sisteem. Ons hipotese was dat die laasgenoemde simpatiese bynier-medulla-sisteem die primêre respons tot sielkundige stres behartig terwyl die HPA-as ‘n sekondêre respons bied. Ons het ons hipotese getoets deur die manupilering van ‘n beproefde stres model waar ons IL-6, ‘n waardevolle rolspeler in die simpatiese bynier-medulla-sisteem, onderdruk het. In respons op stress, het serum kortikosteroon konsentrasies toegeneem slegs in die teenwoordigheid van IL-6 (7 ± 3 vs. 57 ± 4 ng/ml; P<0.0001), maar nie wanneer IL-6 onderdruk is nie (17 ± 7 ng/ml). Stres het ‘n verhoging in hipofise massa teweeggebring slegs tydens die onderdrukking van IL-6 (38 ± 3 vs. 65 ± 6 mg; P <0.001). Stres het ook linker-byniermassa verhoog slegs wanneer voldoende IL-6 beskikbaar was (34 ± 1 vs. 73 ± 8 mg; P <0.00001). Stres alleen het geen invloed gehad op serum IL-1β, IL-6 of TNF-α nie, maar die onderdrukking van IL-6 het wel ‘n inhiberende effek op basale IL-1β en TNF-α gehad. Daarna het ons weer eens die stresmodel manipuleer deur die rotte ‘n S. frutescens ekstrak te gee in ‘n poging om beide die sentrale en perifere effekte daarvan op die sielkundige stres respons te evalueer. Stres alleen het gelei tot ‘n afname in GR terwyl ‘n kombinasie van stres en S. frutescens administrasie tot ‘n afname in GABAARα1 in die hippokampus gelei het. Hierdie kombinasie het ook tot ‘n merkwaardige toename in hipofise massa (P = 0.078) sowel as ACTH-inhoud van die hipofise (P < 0.01) gelei. ‘n Soortgelyke patroon is waargeneem betreffende sirkulerende ACTH en byniermassa met P < 0.05 vir elk. Bynier ACTH inhoud, aan die ander kant, het ‘n omgekeerd eweredige verhouding met ACTH in die hipofise en in sirkulasie getoon. Bynier IL- 6 inhoud het geen statisties beduidende verskille getoon nie, maar ‘n merkwaardige verhoging is weereens gesien met ‘n kombinasie van stres en S. frutescens administrasie. Die soortgelyke tendens wat waargeneem word in GABAAR in die hippokampus, asook hipofise- en sirkulerende ACTH vlakke, en dui op ‘n samewerkende rol van stres en S. frutescens in die aktivering van die sielkundige stres respons. GR in die hippokampus toon geen veranderinge nie. Die resultate van die twee eksperimente dui op ‘n primêre rol van die simpatiese bynier-medulla-sisteem in die respons op ‘n akute stressor en dat die HPA-as net geaktiveer word tydens ‘n ooreiste stres reaksie of indien die simpatiese bynier-medulla-sisteem onderdruk word. Die waargenome “verdowings”-effek van S. frutescens word moontlik deur aktivering van die mesolimbiese dopamien pad deur die hippokampus en amigdala bewerkstellig. Die resultate mag ook lei tot die heroorweging van GABA-gebaseerde angs medikasies.

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.

Le lymphocyte B (LB) joue un rôle important dans la polyarthrite rhumatoïde (PR), en produisant des auto-anticorps qui ont un rôle pathogène, en activant les lymphocytes T, en sécrétant des cytokines pro-inflammatoires et en permettant la formation de centres germinatifs. Plus récemment, il a été montré que le LB pouvait également produire de l'interleukine (IL) 10, une cytokine anti-inflammatoire qui lui procure des fonctions régulatrices. Ces B régulateurs ont notamment la capacité de différencier les lymphocytes T en T régulateurs. De nombreux traitements sont actuellement disponibles dans la PR, notamment les anti-TNF alpha et les inhibiteurs du récepteur de l'IL-6 (tocilizumab). Dans la première partie de cette thèse, nous avons comparé les LB circulants de patients atteints de PR et de contrôles. Nous avons étudié l'influence de l'activité de la maladie et des traitements sur les LB. Nous avons montré qu'il existait une lymphopénie B globale chez les patients atteints de PR avec une répartition des différents sous-types de LB superposable à celle des contrôles. Les patients ayant une maladie active avaient significativement plus de LB mémoires totaux, pré- et post-switch, CD24hiCD27+ et double négatifs que les patients ayant une maladie peu active. Les traitements anti-TNF et le tocilizumab ne modifiaient pas la répartition des sous-types de LB. Nous avons également montré qu'un taux de plus de 26% de LB mémoires CD27+ avant l'instauration d'un traitement par anti-TNF était associé à la réponse clinique à 3 mois. Les LB mémoires semblent produire plus de TNF que les LB naïfs et par ce biais pourraient induire une réponse Th1. Dans la seconde partie de cette thèse, nous avons tout d'abord cherché à mieux définir les LB régulateurs. Nous avons ensuite étudié leur présence et leur rôle dans la PR. Chez les sujets sains, les LB CD24hiCD27+ et CD24hiCD38hi semblent produire plus d'IL-10 que les autres LB, qui peuvent néanmoins en sécréter. Il semble donc plus adapter de définir les B régulateurs comme B producteurs d'IL-10 ou B10. Les patients atteints de PR avaient significativement moins de B10 que les contrôles en pourcentage et en valeur absolue. Chez les patients ayant un facteur rhumatoïde (FR) positif, il y avait une corrélation inverse entre le pourcentage de B10 et le taux de FR. Il y avait une corrélation inverse entre l'activité de la maladie (DAS28) et le pourcentage de B10, qui était particulièrement marquée pour les PR évoluant depuis moins de 5 ans. Chez ces patients, il y avait également une corrélation inverse entre les B10 et l'inflammation biologique (protéine C réactive). L'instauration d'anti-TNF ou de tocilizumab ne modifiait pas le taux de B10. Les CD24hiCD27+ et CD24hiCD38hi induisaient plus de lymphocytes T régulateurs chez les contrôles que les autres LB (CD24lo/-) alors que ça n'était plus le cas chez les patients atteints de PR, montrant que ces sous-types ont perdu cette fonction régulatrice dans la PR. En conclusion, bien qu'il existe une lymphopénie B, la répartition des sous-types de LB ne semble pas différente entre les patients atteints de PR et les contrôles. Néanmoins, il existe des anomalies fonctionnelles avec notamment une perte de la capacité à produire de l'IL-10 et à induire des T régulateurs chez les patients atteints de PR. / B cells play an important role in rheumatoid arthritis (RA), producing autoantibodies which have a pathogenic role, activating T cells, secreting pro-inflammatory cytokines and allowing the formation of germinal centers. More recently, it was shown that the B cells could also produce interleukin (IL)-10, an anti-inflammatory cytokine which provides their regulatory functions. Those regulatory B cells have the ability to differentiate T cell into regulatory T cells. Many treatments are currently available in RA, including TNF-alpha inhibitors and IL-6 receptor inhibitor (tocilizumab). In the first part, we compared circulating B cells in RA patients and in controls, and we studied the influence of disease activity and treatment on B cells. We have shown that there is a global B cell lymphopenia in RA patients with a similar B cell subtype distribution as controls. Patients with active disease had significantly more pre- and post-switch, CD24hiCD27+ and double negative memory B cells than patients with low disease activity. Anti -TNF treatment and tocilizumab did not change the distribution of B cell subsets. We also showed than patient with more than 26% of CD27+ memory B cells prior TNF inhibitor initiation was associated with clinical response at 3 months. Memory B cells produced more TNF alpha than naive B cells and can potentially induce a Th1 response. B cell subtypes were not associated with response to tocilizumab. In the second part, we first sought to better define regulatory B cells. We then studied their presence and role in RA. In healthy subjects, CD24hiCD27+ and CD24hiCD38hi B cells seem to produce more IL-10 than the other B cells that can nevertheless rarely produce some. It seemed more acurate to define regulatory B cells as IL-10 producing B cells also called B10 cells. Patients with RA had significantly less B10 cells than controls in percentage and absolute values. In rheumatoid factor (RF) positive patients, there was an inverse correlation between the percentage of B10 and the rate of RF. There was an inverse correlation between disease activity (DAS28) and the percentage of B10, which was particularly significant for patients with a disease duration of less than 5 years. In these patients, there was also an inverse correlation between B10 and biological inflammation (C-Reactive Protein). TNF inhibitors or tocilizumab did not change B10 cell rate. The CD24hiCD27 + and CD24hiCD38hi induce more regulatory T cells in controls than other LB (CD24lo/-) while it was not the case in patients with RA, indicating that these subtypes have lost this regulatory function in RA. In conclusion, although there are B cell lymphopenia, the distribution of B cell subsets does not seem to differ between RA patients and controls. Nevertheless, there are functional abnormalities including a loss of the ability to produce IL -10 and induce regulatory T in patients with RA.

Objetivos. Avaliar o papel do transplante de células hematopoiéticas (TCH) e da interleucina 6 (IL – 6) sobre vários parâmetros de estresse oxidativo em pacientes com Adrenoleucodistrofia ligada ao cromossomo X (X-ALD). Métodos. A concentração de malondialdeído (MDA), o conteúdo de carbolinas e sulfidrilas e a concentração de ácido hexacosanóico (C26:0) foram quantificados no plasma de pacientes X-ALD antes e após serem submetidos ao TCH. E, a concentração de MDA, a formação de carbonilas e a concentração de IL-6 foram quantificados em plasma e o conteúdo de glutationa reduzida (GSH) foi quantificado em eritrócitos de pacientes X-ALD com fenótipos cerebral infantil (cALD) ou assintomáticos no momento diagnóstico. Resultados. Observamos um aumento significativo na concentração de MDA em plasma de pacientes X-ALD antes e após o TCH em comparação ao grupo controle e uma redução significativa nesses valores após o transplante em comparação aos anteriores ao procedimento. Verificamos uma redução significativa no conteúdo de sulfidrilas no plasma de pacientes X-ALD antes do TCH em comparação ao grupo controle e um aumento significativo desses níveis após o TCH. Não observamos diferenças significativas no conteúdo de carbonilas no plasma de X-ALD antes e após o TCH, em comparação aos controles, apesar de observarmos uma redução significativa nesta determinação nos pacientes após o transplante em relação a antes do TCH. Os pacientes X-ALD apresentam níveis plasmáticos de C26:0 significativamente aumentados antes do TCH em comparação aos controles e, após o TCH, as concentrações de C26:0 foram reduzidas. Observamos uma correlação negativa significativa entre a medida do conteúdo de sulfidrilas e os níveis plasmáticos de C26:0 de indivíduos X-ALD antes do TCH. Também evidenciamos elevados níveis de MDA e da formação de carbonilas no plasma de pacientes cALD e assintomáticos em comparação ao grupo controle. Ainda, observamos redução significativa do conteúdo de GSH nos dois grupos testados comparados aos controles. A quantificação de IL-6 foi significativamente maior nos pacientes cALD, o que não foi observado nos pacientes assintomáticos, apesar destes mostrarem uma tendência de aumento da concentração de IL-6. Conclusões. Os resultados obtidos a partir do plasma de pacientes X-ALD antes e após o TCH demonstram que esta terapia, quando bem indicada e bem sucedida, tem alta efetividade em reduzir a concentração plasmática de C26:0 e é eficaz em reduzir a peroxidação lipídica e o dano oxidativo às proteínas nos pacientes X-ALD. Ainda, é possível relacionar o acúmulo de C26:0 e o dano oxidativo na patogênese da X-ALD. Nossos dados permitem sugerir que a lipoperoxidação e o dano oxidativo às proteínas possam de alguma forma estar envolvidos na fisiopatologia da X-ALD. Além disso, podemos presumir que, nos pacientes X-ALD assintomáticos estudados, o dano oxidativo e os aspectos inflamatórios desempenham papéis importantes na evolução e nas futuras manifestações do fenótipo neuronal. Também podemos supor que a administração de antioxidantes deve ser considerada como uma terapia adjuvante potencial para os pacientes assintomáticos e sintomáticos afetados pela X-ALD, inclusive para aqueles submetidos ao TCH. / Objective. We aimed to evaluate the role of hematopoietic stem cell transplantation (HSCT) and interleukin 6 (IL – 6) on various parameters of oxidative stress in X-linked adrenoleukodystrophy (X-ALD) patients. Methods. Malondialdehyde (MDA), sulfhydryl, carbonyl and hexacosanoic acid (C26:0) levels were measured in plasma from X-ALD patients before and after HSCT. And, MDA, carbonyl and IL-6 levels were measured in plasma and reduced glutathione (GSH) content was measured in erythrocytes from X-ALD patients with different phenotype (asymptomatic and childhood cerebral (CCER patients) at diagnosis moment. Results. We observed increased levels of MDA in plasma from X-ALD before and after HSCT compared to control group, but there was a significant reduction in MDA values after transplantation compared to levels found before the procedure. We verified a significant decrease in sulfhydryl content in plasma of X-ALD patients before HSCT compared with the control group and we also verified a significant increase in the levels of sulfhydryl content after HSCT. No significant differences were observed in carbonyl content in plasma of X-ALD before and after HSCT, compared to controls. However, we observed a significant reduction of plasma carbonyl content from X-ALD patients after HSCT compared to before HSCT. X-ALD patients presented a significant increase of C26:0 plasma level before HSCT when compared to controls and an important reduction of C26:0 plasma concentration in X-ALD patients after HSCT when compared to before HSCT C26:0 levels. We observed an inverse significant correlation between sulfhydryl content and plasma C26:0 levels of X-ALD individuals before HSCT. We also evidenced high levels of MDA and carbonyl formation in plasma from CCER and asymptomatic patients compared to controls. Still, we observed a significant decrease of GSH content in both groups tested compared to controls. The quantification of IL-6 is significantly higher in CCER patients, which is not observed in asymptomatic patients, despite these patients show a tendency of increased concentration of IL-6. Conclusions. The results obtained from plasma of X-ALD patients before and after HSCT demonstrate that this therapy, when well indicated and successful, has high effectiveness in reducing C26:0 plasma and is effective in reducing lipid peroxidation and oxidative damage to proteins in X-ALD patients. Still, it is possible to relate the accumulation of C26:0 and oxidative damage in the pathogenesis of X-ALD. Our data also suggest that lipid peroxidation and protein damage may somehow be involved in the pathophysiology of X-ALD. Moreover, we can assume that in our asymptomatic X-ALD patients, oxidative damage and inflammatory issues seem to play an important role in the evolution and future manifestations of neuronal phenotype. We can also assume that the administration of antioxidants should be considered as a potential adjuvant therapy for asymptomatic and symptomatic patients affected by X-ALD, including those that are submitted to HSCT.

<p>Tissue factor (TF) is the initiator of the coagulation cascade. Monocytes do not normally express TF, but can be induced to do so by certain stimuli. Aberrant TF expression is important in the thrombotic complications of bacterial sepsis, certain malignancies and coronary artery disease (CAD). In this thesis, regulation of monocyte TF by cytokines and by interactions with other vascular cells were studied, as well as the activation of blood cells, inflammation and coagulation in CAD patients and the association of the pro-inflammatory cytokine interleukin (IL)-6 with prognosis in unstable CAD. </p><p>In a whole blood experimental system, the anti-inflammatory cytokine IL-10 was shown to suppress lipopolysaccharide-induced TF expression in monocytes, whereas IL-4 and IL-13 did not, contrary to previous in vitro findings. Activated platelets also induced monocyte TF in whole blood in a P-selectin-dependent manner, causing a rapid surface exposure of TF independent of mRNA formation. The differentiated monocytic cell line U-937 displayed different kinetics of platelet-stimulated TF induction.</p><p>In co-culture with cytokine-activated human coronary artery endothelial cells, U-937 cells expressed TF, and also IL-6. The endothelial cells up-regulated their production of IL-10. Simvastatin, enalapril and dalteparin, all commonly used drugs in CAD treatment, suppressed TF induction but did not alter cytokine expression in co-cultures.</p><p>In unstable CAD, there was an activation of both coagulation and inflammation compared to stable CAD that coincided with an increased activation of platelets and leukocytes. Women had different patterns of cellular activation than men, indicating differences in pathogenetic mechanisms.</p><p>Plasma levels of IL-6 above 5 ng/L proved to be a strong, independent marker for increased risk of death in a 6-12 month perspective in patients with unstable CAD. This risk was significantly reduced by an early invasive strategy.</p>

Allergic diseases are influenced by genetics and the environment. Maternal allergy appears to confer a higher risk for allergic sensitization than paternal allergy, suggesting an in utero influence. A decrease in particular infections or a lower exposure to microbial components during infancy is suggested to contribute to the high allergy prevalence in affluent societies. Toll-like receptors (TLR) 2 and 4 recognize peptidoglycan (PGN) and LPS respectively, are expressed on e.g. monocytes, and have been implicated in modulating the risk of IgE-sensitization. This thesis aimed to study the influence of maternal allergy and early microbial exposure on monocyte function and allergic sensitization during childhood. Blood samples from children participating in a prospective allergy cohort were used. Two-year old infants with allergic mothers had lower IL-6 production and reduced activation of the TLR-signalling intermediate p38-MAPK in response to PGN than children with non-allergic mothers. In 5-year old children, allergic disease and not maternal allergy influenced monocytic TLR2-regulation. Five-year olds who were seropositive for Epstein-Barr virus (EBV) at 2-years of age had a lower risk of persistent IgE-sensitization while EBV contraction after 2-years of age related to a higher risk of IgE-sensitization. Upon in vitro stimulation, NK cells from EBV+ 2-year olds produced lower IFN-g levels. EBV+ 2-year olds had also lower systemic IFN-g. In comparison to CD14++CD16- monocytes, CD14+CD16+ cells induced NK-cell IFN-g more potently in vitro, and EBV+ infants tended to have lower proportions of these CD14+CD16+ monocytes. This thesis highlights the importance of early-life microbial (EBV) exposure for a proper allergy-protective immunity. Also, maternal allergic heredity appears to influence monocytic microbial responses in early infancy. All these aspects relate to altered monocyte functionality, which suggest that they could have a role in allergic sensitization.

<p>This study shows that herbs can be effectively screened for potiential bio-activity using in vitro methods. Further studies will be needed to better explore Artemisia afra&rsquo / s effect on immunoregulation, particularly long term effects of the herb on the immune system and its effect on other disease states.</p>