<p>The main focus of my thesis has been to develop protocols for generating antigen-specific cytotoxic T lymphocytes (CTLs) and T helper cells (T<sub>H</sub>) for adoptive transfer to treat cytomegalovirus (CMV) disease and prostate cancer. CMV viremia is a severe complication in immunocompromised stem cell transplanted patients. Prostate cancer is a leading cause of death for men in Western countries. Although different in nature, CMV-infected cells and prostate cancer cells can both be eliminated through specific activation of the adaptive immune system. </p><p>To generate CMV pp65-specific T cells, I utilized dendritic cells (DCs) modified with an HLA-A*0201/pp65<sub>495-503</sub> peptide, a recombinant adenovirus coding for pp65, <i>in vitro</i> transcribed pp65 mRNA and a recombinant pp65 protein. Peptide stimulation yielded large numbers of peptide-specific CD8<sup>+</sup> T cells with high lytic activity while adenovirus or mRNA stimulation resulted in the expansion of CTLs against multiple pp65 epitopes. The recombinant protein activated primarily CD4<sup>+</sup> T<sub>H</sub> cells. Stimulation with DCs co-modified with pp65 mRNA and pp65 protein simultaneously generated both pp65-specific CTLs and T<sub>H</sub> cells. Such T cells would cover all pp65 epitopes while avoiding potential virus related biohazards. The mRNA/protein combinatory approach can be used to stimulate T cells <i>ex vivo</i> from virtually all stem cell donors for adoptive T cell transfer. </p><p>I have identified two immunogenic HLA-A*0201-restricted peptide epitopes from the prostate tissue antigen TARP. Repeated stimulations with TARP peptide-pulsed DCs yielded up to 20% TARP-directed CD8<sup>+</sup> T cells even when starting from undetectable frequencies (<0.01%). The T cells could be sorted to 99% purity and expanded 1000-fold with retained specificity and activity. We also detected TARP-directed CD8<sup>+</sup> T cells in the blood of prostate cancer patients. Therefore, TARP seems to have potential as antigen in DC vaccination or adoptive T cell therapy of prostate cancer. </p>
| Identifer | oai:union.ndltd.org:UPSALLA/oai:DiVA.org:uu-4821 |
| Date | January 2005 |
| Creators | Carlsson, Björn |
| Publisher | Uppsala University, Clinical Immunology, Uppsala : Acta Universitatis Upsaliensis |
| Source Sets | DiVA Archive at Upsalla University |
| Language | English |
| Detected Language | English |
| Type | Doctoral thesis, comprehensive summary, text |
| Relation | Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Medicine, 1651-6206 ; 15 |
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