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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Studies of cytotoxic T lymphocytes and natural killer cells in relation to MHC class I presented peptides /

Franksson, Lars, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 6 uppsatser.
2

3-Dimensional reconstruction of the breast tumour microenvironment: mediation of tumour progression by T(REG) lymphocytes and NK cells

Augustine, Tanya Nadine 21 April 2015 (has links)
A thesis submitted in fulfilment of the requirements for the Degree of Doctor of Philosophy FACULTY OF HEALTH SCIENCES UNIVERSITY OF THE WITWATERSRAND, JOHANNESBURG 2014 / Breast tumour progression involves complex interactions between malignant cells and the tumour microenvironment. It is increasingly apparent that immunity is a critical determinant for tumour progression. T regulatory (TREG) lymphocytes, which dominate tumour infiltrating lymphocyte populations, are implicated in facilitating tumour immunoediting processes and suppressing Natural Killer (NK) cell anti-tumour function. To investigate such cellular interaction, experimentation traditionally involves using reductionist 2-dimensional culture systems that do not recapitulate the spatial dimensions of the in vivo microenvironment. Three-dimensional (3D) culture systems, conversely, recreate these dimensions, allowing tumour cells to assume a phenotype more representative of the tumour microenvironment. Given that immunity is a critical factor in determining tumour progression, a novel 3D culture system was established to investigate the interactions between TREG lymphocytes, NK cells and hormone-dependent (MCF-7) or hormone-independent (MDA-MB-231) breast cancer cells. Lymphocyte subpopulations were magnetically isolated, with the efficacy of the sorting procedure verified using flow cytometry. To generate 3D cultures, cell populations were resuspended in growth factor-reduced Matrigel and cultured for 72 hours. This culture system proved effective for RNA extraction for downstream applications; for immunolocalisation of selected tumour biomarkers (ER-α, TGF-β, MUC-1 and EGFR) for qualitative analysis; and for acquisition of cytokine data (IL-1β, IL-2, IL-6, TNF-α, IFN-, CCL2, CCL4 and CXCL8) for quantitative multivariate statistical analysis. Immune mediation was shown to induce the disruption of cell-cell associations, altering the expression of biomarkers and secreted cytokine profiles. Collectively, these results reflect tumour cell subversion of NK cell and/or TREG lymphocyte function to promote tumour progression by generating an inflammatory microenvironment. While hormone-dependent and hormone-independent breast cancer cells differed in their specific response to immune mediation, the mechanisms by which they elicited responses resulted in similar outcomes – that of enhanced evasive and invasive capacity. It is necessary to further elucidate the relationship between the investigated cytokines, biomarkers and immune cells, to understand their interactions and potentially provide more information for therapeutic intervention, given that these factors may contribute to tumours not responding favourably to combined modalities of therapy.
3

Cytomegalovirus evasion of natural killer cell immunity /

Lodoen, Melissa. January 2004 (has links)
Thesis (Ph.D.)--University of California, San Francisco, 2004. / Bibliography: leaves 85-92. Also available online.
4

Avaliação da participação das células NK (células CD56+) na resposta ao paracoccidioides brasiliensis / Evaluation of the role of natural killer cells (CD56+ cells) in the immunological response against paracoccidioides brasiliensis infection

Longhi, Larissa Nara Alegrini, 1982- 16 August 2018 (has links)
Orientadores: Ronei Luciano Mamoni, Maria Heloisa Souza Lima Blotta / Dissertação (mestrado) - Universidade Estadual de Campinas. Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-16T10:37:38Z (GMT). No. of bitstreams: 1 Longhi_LarissaNaraAlegrini_M.pdf: 6631958 bytes, checksum: 45b4fc2e64262b037302e0269ebd8f71 (MD5) Previous issue date: 2010 / Resumo: Tradicionalmente o papel das células NK na resposta imunológica tem sido associado com a resistência à infecção viral e tumores, porém estudos recentes apontam para a participação destas células na resposta imunológica contra outras doenças infecciosas. O objetivo deste estudo foi avaliar a possível participação de células NK (CD56+CD3-) na resposta imunológica ao fungo Paracoccidioides brasiliensis. Foram utilizadas células CD56+ isoladas por meio imunomagnético provenientes de pacientes com paracoccidioidomicose e de indivíduos controle. As células CD56+ foram avaliadas quanto à capacidade citotóxica direta contra leveduras de P. brasiliensis (cepa virulenta - Pb18 e avirulenta - Pb265) e contra células-alvo (monócitos) infectadas com leveduras de ambas as cepas. Também foi avaliada a expressão dos constituintes dos grânulos citotóxicos (granzima A, B, perforina e granulisina), receptores de ativação (NKG2D) e de inibição (KIR2DL2/L3/S2 e KIR3DL1), marcadores de ativação (CD69 e CD25), assim como a produção de citocinas (IFN-g e TNF-a) por meio de PCR em tempo real e por citometria de fluxo. A participação da IL-15 na ativação das células NK foi avaliada pela adição da citocina recombinante em alguns experimentos. Para avaliar a participação dos grânulos na atividade citotóxica direta e contra células-alvo em alguns experimentos as células foram tratadas com inibidores específicos (SrCl, concanamicina A ou EGTA). Os resultados demonstraram que células de pacientes apresentam resposta citotóxica (direta e contra células-alvo) inferior àquela observada nos indivíduos controle. A citotoxicidade direta foi dependente de grânulos, mas independente de perforina, enquanto que a citotoxicidade contra células-alvo foi dependente de perforina. A expressão de granulisina (RNAm e proteína) foi maior nas células de indivíduos controle. Além disso, observamos que células CD56+ apresentam a capacidade de secretar essa proteína após o estímulo com leveduras de P. brasiliensis. Também observamos que as células CD56+ de doadores normais são ativadas (aumentam a expressão de CD69 e CD25) quando estimuladas com o fungo, enquanto as células NK de pacientes não mostraram esse aumento, a não ser quando estimuladas com IL-15. Estes resultados demonstraram que as células CD56+ podem participar ativamente da resposta imunológica contra o P. brasiliensis, podendo contribuir tanto para a morte direta do fungo como de células infectadas, e que a granulisina pode desempenhar um papel preponderante no controle da infecção pelo P. brasiliensis. Outro fato importante observado foi que as células CD56+ quando estimuladas por células leveduriformes de P. brasiliensis produzem e secretam IFN-g, uma citocina com atuação importante na ativação de outras células do sistema imunológico como macrófagos e linfócitos, e dessa forma pode contribuir para o desenvolvimento da resposta imunológica adquirida subseqüente à infecção. / Abstract: Besides their role in viral infection and tumor resistance, recent studies have showed that NK cells also participate in the immune response against other infectious diseases. The aim of this study was to evaluate the possible role for NK cells (CD56+) in the immune response against the fungi Paracoccidioides brasiliensis. CD56+ cells from patients with paracoccidioidomycosis and healthy individuals were isolated by immmunomagnetic columms and antibodies. We evaluated the capacity of the direct killing of P. brasiliensis yeast cells (Pb18 virulent strain and Pb285 avirulent strain), as well as, the ability to kill infected target cells (monocytes infected with either virulent or avirulent strains). The CD56+ cells also were assessed in order to evaluate the expression of citotoxic granules (granzyme A, B, perforin and granulysin) and the expression of the activation receptor NKG2D, the inhibition receptors KIR2DL2/L3/S2 and KIR3DL1 and the activation molecules CD69 and CD25. We also determine the capability of production and release of cytokines (IFN-g and TNF-a) using Real Time PCR, flow cytometry and ELISA. The role of IL-15 was analyzed by the addition of recombinant cytokine in some experiments. To determine if the cytotoxic activity was dependent of granules, cell cultures were supplemented with specific inhibitors which prevent granule release. The results showed that cells from patients present a lower citotoxic response when compared to healthy individuals. The direct citotoxicity seems to be granule-dependent but independent on perforin, whereas the citotoxicity against target cells showed to be perforin dependent. It was observed an augmented expression of granulysin (mRNA and protein) in cells from controls, and that CD56+ cells are able to produce and release granulysin after stimulation with P. brasiliensis yeast cells. Furthermore, the analyses of CD56+ cells from controls showed elevated expression of CD25 and CD69 after the stimulus with yeast cells, while cells from patients are only activated in the presence of IL-15. These results demonstrated that CD56+ cells can participate actively of the immune response against the P. brasiliensis infection either by destroying directly yeast cells or by the recognition and killing of infected cells. Granulysin is the possible mediator of the cytotoxic effect observed in this study, once this protein is produced and released by CD56+ cells. Another important data is the finding that CD56+ cells are able to produce IFN-g after the stimulus, which could influence the subsequent acquired immunological response by stimulating others cells as macrophages and lymphocytes. / Mestrado / Ciencias Biomedicas / Mestre em Ciências Médicas
5

Natural killer cell inhibitory and activating receptors : regulatory role in effector functions against normal and tumor cells /

Vahlne, Gustaf, January 2007 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 4 uppsatser.
6

Therapeutic potential of natural killer cells in multiple myeloma /

Alici, Evren, January 2006 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2006. / Härtill 4 uppsatser.
7

Genetic analysis of natural killer cell mediated virus immunity in related strains of New Zealand inbred mice and their hybrid offspring /

Rodriguez, Marisela Raquel. January 2008 (has links)
Thesis (Ph. D.)--University of Virginia, 2008. / Includes bibliographical references. Also available online through Digital Dissertations.
8

Intercellular protein transfer and regulation of inhibitory NK cell receptor accessibility /

Andersson, Katja, January 2007 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 4 uppsatser.
9

Study on inflammatory responses of neonatal natural killer cells and macrophages upon lipoteichoic acid stimulation. / 脂磷壁酸對新生兒自然殺傷細胞和巨噬細胞免疫反應的影響 / Zhi lin bi suan dui xin sheng er zi ran sha shang xi bao he ju shi xi bao mian yi fan ying de ying xiang

January 2011 (has links)
Cheng, Siu Fung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 121-141). / Abstracts in English and Chinese. / Abstract (English) --- p.ii / (Chinese) --- p.V / Acknowledgements --- p.viii / List of Abbreviations --- p.x / Table of Contents --- p.xi / Chapter Chapter 1 --- Introduction and Literature Reviews --- p.1 / Chapter 1.1 --- Bacterial Infection in Neonates --- p.1 / Chapter 1.1.1 --- Overview of Bacterial Infection in Neonates --- p.1 / Chapter 1.1.2 --- Gram-Positive Bacteria and Infection in Newborns --- p.2 / Chapter 1.1.3 --- Lipoteichoic Acid - the Immunostumulatory Component of Gram-Positive Bacteria --- p.5 / Chapter Figure 1.1 --- Schematic Representation of Gram-Positive Bacterial Cell Wall --- p.8 / Chapter Figure 1.2 --- Structure of Lipoteichoic Acid Polymer --- p.9 / Chapter 1.2 --- The Immune System of the Neonate --- p.10 / Chapter 1.2.1 --- Overview of the Human Immune System --- p.10 / Chapter 1.2.2 --- Innate Immune System --- p.10 / Chapter 1.2.3 --- Adaptive immune system --- p.13 / Chapter 1.3 --- Macrophages --- p.15 / Chapter 1.3.1 --- Overview of Macrophages --- p.15 / Chapter 1.3.2 --- Functions of Macrophages --- p.16 / Chapter 1.3.3 --- Macrophages in Gram-Positive Bacterial Infection --- p.19 / Chapter 1.4 --- Natural Killer Cells --- p.21 / Chapter 1.4.1 --- Overview of Natural Killer Cells --- p.21 / Chapter 1.4.2 --- Activation of Natural Killer Cells --- p.23 / Chapter 1.4.3 --- Functions of Natural Killer Cells --- p.24 / Chapter 1.4.4 --- Activation Markers on Natural Killer Cell Surface --- p.27 / Chapter Figure 1.3 --- Schematic Diagram of CD 107a Expression in NK Cells During Degranulation --- p.30 / Chapter 1.5 --- Interactions Between Macrophages and Natural Killer Cells --- p.31 / Chapter 1.6 --- Mitogen-Activated Protein Kinases (MAPKs) and Infection --- p.32 / Chapter 1.7 --- ApolipoproteinA-1 (ApoA-1) and Infection --- p.34 / Chapter 1.8 --- Overall Objectives of the Study --- p.36 / Chapter Chapter 2 --- Materials and Methods --- p.37 / Chapter 2.1 --- Reagents Used --- p.37 / Chapter 2.2 --- Sampling Methods --- p.41 / Chapter 2.3 --- Mononuclear Cell Isolation --- p.41 / Chapter 2.4 --- Mononuclear Cell Cryopreservation --- p.42 / Chapter 2.5 --- Induction of Macrophage from MNC culture --- p.42 / Chapter 2.6 --- Enrichment of Natural Killer (NK) Cells from MNC --- p.43 / Chapter 2.7 --- Culture of NK Cells Using Conditioned Medium Collected From LTA-Stimulated Macrophages --- p.45 / Chapter 2.8 --- Western Blotting --- p.46 / Chapter 2.9 --- Cytokines in Culture Supernatant of Macrophages --- p.50 / Chapter 2.10 --- CD107a Assay --- p.51 / Chapter 2.11 --- CD69 Assay --- p.52 / Chapter 2.12 --- Statistical Analysis --- p.53 / Chapter Figure 2.1 --- A Representative Diagram to Show NK Cell Purity After Enrichment by Immuno-Magnetic Beads --- p.55 / Chapter Figure 2.2 --- A Diagram to Illustrate the Gating Method Used in CD 107a Assay --- p.56 / Chapter Figure 2.3 --- A Diagram to Illustrate the Gating Method Used in CD69 Assay --- p.58 / Chapter Chapter 3 --- Lipoteichoic Acid - Induced Inflammatory Responses of Cord Blood Macrophages in vitro --- p.59 / Chapter 3.1 --- LTA-Stimulated Secretion of Tumor Necrosis Factor-Alpha in Cord Blood Macrophages --- p.60 / Chapter 3.2 --- LTA-Stimulated Secretion of Interleukin-6 in Cord Blood Macrophages --- p.61 / Chapter 3.3 --- LTA-Stimulated Secretion of Interleukin-12 in Cord Blood Macrophages --- p.62 / Chapter 3.4 --- LTA-Stimulated Phosphorylation of P44/42 Mitogen-Activated Protein Kinase (ERK1/2) in Cord Blood Macrophages --- p.63 / Chapter 3.5 --- The Effect of Apolipoprotein A-l Pre-Treatment on LTA-Stimulated P44/42 Mitogen-Activated Protein Kinase (Erkl/2) Phosphorylation --- p.64 / Chapter 3.6 --- Discussion --- p.65 / Chapter Figure 3.1 --- LTA-Induced TNFa Secretion by Cord Blood Macrophages --- p.73 / Chapter Figure 3.2 --- LTA-Induced IL-6 Secretion by Cord Blood Macrophages --- p.74 / Chapter Figure 3.3 --- LTA-Induced IL-12 Secretion by Cord Blood Macrophages --- p.75 / Chapter Figure 3.4 --- Phosphorylation of P44/42 MAPK (ERK1/2) Stimulated by LTA in Cord Blood Macrophages --- p.76 / Chapter Figure 3.5 --- The Effect of ApolipoproteinA-1 on LTA-Stimulated P44/42 MAPK Phosphorylation --- p.78 / Chapter Chapter 4 --- Lipoteichoic Acid - Induced Inflammatory Responses of Natural Killer Cells in vitro --- p.80 / Chapter 4.1 --- Dose-Dependent Effect of IL-15 on CD69 Expression --- p.80 / Chapter 4.2 --- Effects of LTA on CD69 Surface Expression in NK Cells --- p.82 / Chapter 4.3 --- Effects of LTA on CD 107a Surface Expression in NK Cells --- p.84 / Chapter 4.4 --- Discussion --- p.87 / Chapter Figure 4.1 --- Dose-Dependent Effect of IL-15 on Cord Blood NK Cells CD69 Surface Expression --- p.93 / Chapter Figure 4.2 --- Effects of LTA and IL-15 on CD69 surface Expression in NK Cells --- p.95 / Chapter Figure 4.3 --- Effects of LTA and IL-15 on CD 107a surface Expression in NK Cells --- p.97 / Chapter Chapter 5 --- Effects of LTA-Primed Macrophage-Conditioned Medium on Autologous Natural Killer Cell Activation --- p.99 / Chapter 5.1 --- Effects of Macrophage-Conditioned Medium on Autologous NK Cell CD 107a Expression --- p.100 / Chapter 5.2 --- Effects of LTA-Stimulated Macrophages on Autologous NK cells CD69 Expression --- p.102 / Chapter 5.3 --- Discussion --- p.105 / Chapter Figure 5.1 --- Flow Chart of the Experiment Design --- p.110 / Chapter Figure 5.2 --- Effects of Macrophage-Conditioned Medium on Autologous NK CD 107a Expression --- p.111 / Chapter Figure 5.3 --- Effects of Macrophage-Conditioned Medium on Autologous NK CD69 Expression --- p.113 / Chapter Chapter 6 --- Conclusion and General Discussion --- p.115 / Chapter 6.1 --- Conclusion --- p.115 / Chapter 6.2 --- Potential Applications of the Findings --- p.117 / Chapter 6.3 --- Limitations --- p.118 / Chapter 6.4 --- Further Studies --- p.119 / References --- p.121
10

Migration of natural killer cells : matrix interaction, locomotion and regulation of matrix metalloproteinases (MMPs) by IL-2 and chemokines /

Edsparr, Karin, January 2009 (has links)
Diss. (sammanfattning) Göteborg : Göteborgs universitet, 2009. / Härtill 4 uppsatser.

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