Item – Theses Canada

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OCLC number
732947823
Link(s) to full text
LAC copy
LAC copy
Author
Thomas, Bradley Scott,1977-
Title
A study of the therapeutic value of the Mashkiki bacteriophage : a lambda display and subunit vaccine system.
Degree
Ph. D. -- University of Calgary, 2009
Publisher
Ottawa : Library and Archives Canada = Bibliothèque et Archives Canada, [2010]
Description
3 microfiches
Notes
Includes bibliographical references.
Abstract
The utility of bacteriophage lambda ([lambda]) phage display, herein coined Mashkiki, has been investigated. Mashkiki phage displaying TAT proved ineffective for delivery of recombinant genetic cargos. However, Mashkiki phage did prove effective for antigen presentation to the immune system. As a subunit vaccine vector, [lambda] was shown to be a potent stimulus for splenocytes, regardless of immunization. The pro-inflammatory nature of Mashkiki was associated with IFN[gamma] production. This co-stimulatory signal produced cellular and humoral immunity against [lambda] and antigen. Antigen was effectively presented with [lambda] as either a displayed peptide or by genetic immunization. The adjuvant activity of Mashkiki phage was examined and was found to be intriguing. A study to find the pattern recognition receptor responsible for [lambda] adjuvant activity ensued. [lambda] was found to cause TLR4 receptor ligation, therefore a vaccine trial was performed with Mashkiki phage in the TLR4 hypo-responsive mutant C3H/HeJ. The humoral immune response to [lambda] was found to be TLR4-independent, as titers of [lambda] recognizing antibodies were equivalent between C3H/HeJ mice and the TLR4 responsive mouse strain C3H/HeOuJ. Interestingly, the adjuvant activity for a [lambda] displayed antigen was 1 log10 weaker in C3H/HeJ mice than 'wt' C3H/HeOuJ. In order to determine the involvement of TLR4 in adjuvant activity, downstream signalling pathways from TLR4 were assayed for activity after [lambda] treatment. TLR4 ligation with [lambda]gfp10-TAT-GFP caused activation of the NF-[kappa][beta] pathway in a TLR4-independent fashion, but lack of MyD88 attenuated activation. In contrast signalling through p38 was largely TLR4-dependent, but MyD88-independent. In the context of TLR signalling, MAPK signalling is therefore TRIF-dependent, and results in IP10 expression. On the other hand NF-[kappa][beta] signalling was largely MyD88-dependent and signalling resulted in IFN[gamma] and IL-6 expression. The cytokines produced from this response, which differ in timing and amplitude from LPS, the prototypical TLR4 ligand, are: IFN[gamma], IL-2, IL-6, IL-10, IL-13, IL17a, IP-10, and MIP-1[alpha]. The initiation of an adaptive immune response from [lambda] is therefore multifaceted. The adjuvant activity of [lambda] is not TLR4 restricted. It is postulated that [lambda] will provide immune stimulation through TLR9, a NOD-like receptor. (Abstract shortened by UMI.)
ISBN
9780494544495
049454449X