Graduate Thesis Or Dissertation
 

The role of costimulation and adjuvants in the development of T cell effector and memory responses

Público Deposited

Contenido Descargable

Descargar PDF
https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/1z40kw30d

Descriptions

Attribute NameValues
Creator
Abstract
  • T cells are one of the key cells in the immune system. Although they are not the first line of defense against a pathogen, their functions can greatly enhance the phagocytosis and destruction of pathogens as well as the development of antibody responses. Furthermore, even when responding T cells have facilitated the clearance of the pathogen, they can avoid death to become long-lived cells that "remember" encountering the pathogen for years afterward. This long-term memory allows subsequent immune responses to improve with each exposure, ultimately preventing disease upon reinfection. The activation of these T cells depends on specific recognition of antigen along with a costimulatory signal. This activation process is well studied, but not completely understood. Additionally, the mechanism behind memory T cell development is still very much unknown. In the work presented in this thesis, delivery of costimulatory signals via CD4O and 0X40 were studied using an in vivo superantigen (SAg) model of T cell stimulation. In the context of this two-signal (SAg + costimulation) model, both CD4O and OX40 could deliver signals that enhanced SAg-reactive T cell clonal expansion, but they could only partially prevent T cell death. Coadministration of the inflammatory agent lipopolysaccharide (LPS), however, could keep increased responder T cell populations alive for at least two months. Interestingly, this three-signal (SAg + costimulation + LPS) induced survival was not dependent on proinflammatory cytokines or activation of the transcription factor NF-KB, but was sensitive to the immunosuppressant cyclosporin A (CsA). The mode of action of CsA may point to the mechanism driving long-term T cell survival. Additionally, examination of early time points after three-signal stimulation suggested more clues to the mechanism of survival induction. The cytokines IL-2 and TNF-α seem to be involved early on, but for now, little is known about their complete role. Thus, the goal of this work was to investigate the costimulatory and adjuvant-mediated signals required for memory T cell development. Ultimately, an understanding of how memory T cells can be generated could be used to enhance vaccine efficacy or shut off autoimmune conditions.
License
Resource Type
Fecha Disponible
Fecha de Emisión
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Advisor
Academic Affiliation
Non-Academic Affiliation
Subject
Declaración de derechos
Publisher
Peer Reviewed
Language
Digitization Specifications
  • File scanned at 300 ppi (Monochrome, 8-bit Grayscale) using ScandAll PRO 1.8.1 on a Fi-6770A in PDF format. CVista PdfCompressor 4.0 was used for pdf compression and textual OCR.
Replaces

Relaciones

Parents:

This work has no parents.

En Collection:

Elementos