| 1. |
- Carlsson, Björn, et al.
(författare)
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Ex vivo stimulation of cytomegalovirus (CMV)-specific T cells using CMVpp65-modified dendritic cells as stimulators
- 2003
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Ingår i: British Journal of Haematology. - : Wiley. - 0007-1048 .- 1365-2141. ; 121:3, s. 428-38
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Tidskriftsartikel (refereegranskat)abstract
- Cytomegalovirus (CMV) infection is a dangerous complication in immunosuppressed individuals such as allogeneic stem cell transplant patients. CMV disease can be prevented by the early post-transplant transfer of donor-derived, CMV-directed, T cells. Fast and cost efficient methods to generate CMV-specific T cells are, therefore, warranted. The current study utilized peptide-pulsed and adenovirus-transduced dendritic cells (DC) to generate CMV-restricted T cells. After one stimulation with CMV pp65495-503 peptide-pulsed DC and three re-stimulations with peptide-pulsed monocytes, virtually all T cells were CD8+, expressed the relevant T cell receptor and exhibited high peptide-specific lytic activity. After only one stimulation, pp65495-503-restricted T cells could be sorted to a purity of higher than 95% and expanded up to 1000-fold in 2 weeks. This technique may prove useful for the rapid generation of large quantities of specific cytolytic T lymphocytes (CTL) for cell therapy. DC transduced with an adenoviral vector encoding the full-length pp65 protein (Adpp65) were able to simultaneously expand CTL against multiple epitopes of pp65. In addition, they activated CMV-specific CD4+ T-helper cells. This approach would stimulate multiple-epitope populations of pp65-specific T cells and could be made available to patients of any human leucocyte antigen (HLA) haplotype. DC transduced with adenoviral vectors to express full-length antigens may prove to be potent vaccines against viral pathogens and cancer.
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| 2. |
- Carlsson, Björn, et al.
(författare)
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Generation of cytotoxic T lymphocytes specific for the prostate and breast tissue antigen TARP
- 2004
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Ingår i: The Prostate. - : Wiley. - 0270-4137 .- 1097-0045. ; 61:2, s. 161-170
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Expansion of cytotoxic T lymphocytes (CTL) directed against peptide epitopes from antigens that are specifically expressed by normal and neoplastic prostate epithelial cells has during the last years emerged as an interesting therapeutic approach to treat advanced prostate cancer. TCRgamma alternate reading frame protein (TARP) is a protein that in males is specifically expressed by normal prostate epithelial cells and prostate cancer cells. We have evaluated TARP for human leukocyte antigen (HLA)-A*0201-restricted peptides capable of triggering TARP-specific CTL. METHODS: Dendritic cells (DC) were pulsed either with synthetic peptides derived from the natural amino acid sequence of TARP or with cognate peptides having enhanced affinity for HLA-A*0201 due to an N-terminal anchor residue substitution. The peptide-pulsed DC were used to stimulate autologous T cells ex vivo. RESULTS: We were able to generate T cells against TARP(27-35) and TARP(4-13) and their mutated counterparts TARP(V28L)(27-35) and TARP(P5L)(4-13). The use of affinity-enhanced peptides resulted in the generation of T cells recognizing target cells displaying either wild-type or mutated peptide. We further show that TARP-specific T cells can be tetramer-sorted and subsequently expanded to large numbers by general T cell stimulation, with retained specificity and activity. Sorted and expanded T cells, obtained by stimulation with TARP(P5L)(4-13), exert moderate lysis of the TARP-expressing prostate cancer cell line, LNCaP, and breast cancer cell line, MCF-7, indicating that the TARP(4-13) epitope may be endogenously processed and presented by TARP-positive, HLA-A*0201-positive cells. CONCLUSIONS: Our findings suggest that synthetic TARP peptides, such as TARP(P5L)(4-13), may play a role in prostate and breast cancer immunotherapy.
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| 3. |
- Cheng, Wing-Shing, et al.
(författare)
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A novel TARP-promoter-based adenovirus against hormone-dependent and hormone-refractory prostate cancer
- 2004
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Ingår i: Molecular Therapy. - : Elsevier BV. - 1525-0016 .- 1525-0024. ; 10:2, s. 355-364
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Tidskriftsartikel (refereegranskat)abstract
- TARP (T cell receptor gamma-chain alternate reading frame protein) is a protein that in males is uniquely expressed in prostate epithelial cells and prostate cancer cells. We have previously shown that the transcriptional activity of a chimeric sequence comprising the TARP promoter (TARPp) and the PSA enhancer (PSAe) is strictly controlled by testosterone and highly restricted to cells of prostate origin. Here we report that a chimeric sequence comprising TARPp and the PSMA enhancer (PSMAe) is highly active in testosterone-deprived prostate cancer cells, while a regulatory sequence comprising PSAe, PSMAe, and TARPp (PPT) has high prostate-specific activity both in the presence and in the absence of testosterone. Therefore, the PPT sequence may, in a gene therapy setting, be beneficial to prostate cancer patients that have been treated with androgen withdrawal. A recombinant adenovirus vector with the PPT sequence, shielded from interfering adenoviral sequences by the mouse H19 insulator, yields high and prostate-specific transgene expression both in cell cultures and when prostate cancer, PC-346C, tumors were grown orthotopically in nude mice. Intravenous virus administration reveals both higher activity and higher selectivity for the insulator-shielded PPT sequence than for the immediate-early CMV promoter. Therefore, we believe that an adenovirus with therapeutic gene expression controlled by an insulator-shielded PPT sequence is a promising candidate for gene therapy of prostate cancer.
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| 4. |
- Cheng, Wing-Shing, et al.
(författare)
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Characterization of the androgen-regulated prostate-specific T cellreceptor gamma-chain alternate reading frame protein (TARP) promoter.
- 2003
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Ingår i: Endocrinology. ; 144:8, s. 3433-40
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Tidskriftsartikel (refereegranskat)abstract
- TARP (T cell receptor gamma-chain alternate reading frame protein) is uniquely expressed in males in prostate epithelial cells and prostate cancer cells. Here we demonstrate that TARP expression is regulated by testosterone at the transcriptional level through specific binding of androgen receptor to an androgen response element in the proximal TARP promoter. We further demonstrate that the promoter specifically initiates reporter gene expression in TARP-positive prostate cancer cell lines. To develop a regulatory sequence for prostate-specific gene expression, we constructed a chimeric sequence consisting of the TARP promoter and the prostate-specific antigen (PSA) enhancer. We found that in the prostatic adenocarcinoma cell line LNCaP, the transcriptional activity of the regulatory sequence consisting of a TARP promoter and PSA enhancer is 20 times higher than the activity of a regulatory sequence consisting of the PSA promoter and PSA enhancer. Thus, our studies define a regulatory sequence that may be used to restrict expression of therapeutic genes to prostate cancer cells and may therefore play a role in prostate cancer gene therapy.
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| 5. |
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| 6. |
- Loskog, Angelica, et al.
(författare)
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Adenovirus CD40 Ligand Gene Therapy Counteracts Immune Escape Mechanisms in the Tumor Microenvironment
- 2004
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Ingår i: Journal of Immunology. - 0022-1767 .- 1550-6606. ; 172:11, s. 7200-7205
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Tidskriftsartikel (refereegranskat)abstract
- Tumors exhibit immune escape properties that promote their survival. These properties include modulation of Ag presentation, secretion of immunosuppressive factors, resistance to apoptosis, and induction of immune deviation, e.g., shifting from Th1- to Th2-type responses. These escape mechanisms have proven to hamper several immunotherapeutic strategies, and efforts need to be taken to revert this situation. We have studied the immunological effects of introducing CD40 ligand (CD40L), a potent dendritic cell activation molecule, into the tumor micromilieu by adenoviral gene transfer. For this purpose, a murine bladder cancer model (MB49) was used in C57BL/6 mice. The MB49 cells are known to induce IL-10 in the tumor environment. IL-10 potently inhibits the maturation of dendritic cells and thereby also the activation of CTLs. In this paper we show that CD40L immunogene therapy suppresses IL-10 and TGF-beta production (2-fold decrease) and induces a typical Th1-type response in the tumor area (200-fold increase in IL-12 production). The antitumor responses obtained were MB49 cell specific, and the cytotoxicity of the stimulated CD8(+) cells could be blocked by IL-10. Adenovirus CD40L therapy was capable of regressing small tumors (five of six animals were tumor free) and inhibiting the progression of larger tumors even in the presence of other escape mechanisms, such as apoptosis resistance. Furthermore, CD40L-transduced MB49 cells promoted the maturation of dendritic cells (2-fold increase in IL-12) independently of IL-10. Our results argue for using adenovirus CD40L gene transfer, alone or in combination with other modalities, for the treatment of Th2-dominated tumors.
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| 7. |
- Olsson, Par, et al.
(författare)
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GDEP, a new gene differntially expressed in normal prostate and prostate cancer.
- 2001
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Ingår i: Prostate. ; 48:4, s. 231-41
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The database of human expressed sequence tags (dbEST) is a potential source for the identification of tissue specific genes. The database contains sequences that originate from cDNA libraries from different tissues cell types and tumors. METHODS: Computer based analysis identified a cluster of sequence homologous ESTs, containing ESTs derived only from human prostate cDNA libraries. The tissue specificity was examined by multiple tissue RNA dot blots and RT-PCR. The new RNA transcript was characterized using northern blot analysis, RACE-PCR, and a ribonuclease protection assay. RESULTS: We have identified a gene differentially expressed in prostate using EST database analysis and experimental studies. We name the gene GDEP for gene differentially expressed in prostate. The major GDEP transcript is about 520 bp long. GDEP RNA was detected in nine prostate tissue samples, four normal and five cancer. Expression in prostate epithelial cells was established by in situ hybridization. Weak expression was detected in the prostate cancer cell line LNCaP. In vitro transcription/translation indicate that the RNA encodes a small 34 amino acid protein. The major transcript consists of two exons with one large intron (> 15 kb). The GDEP gene was mapped to chromosome 4q21.1 by radiation hybrid mapping. CONCLUSIONS: Our data proves that tissue specific genes can be identified by EST database mining. The prostate specificity of GDEP expression indicates that GDEP may be useful in the diagnosis or treatment of prostate cancer.
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| 8. |
- Wolfgang, CD, et al.
(författare)
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T cell receptor gamma chain alternate reading frame protein (TARP) expression in prostate cancer cells leads to an increased growth rate and induction of caveolins and amphiregulin.
- 2001
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Ingår i: Cancer Res.. ; 61:22, s. 8122-6
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Tidskriftsartikel (refereegranskat)abstract
- Previously, we showed that prostate and prostate cancer cells express a truncated T-cell receptor gamma chain mRNA that uses an alternative reading frame to produce a novel nuclear T-cell receptor gamma chain alternate reading frame protein (TARP). TARP is expressed in the androgen-sensitive LNCaP prostate cancer cell line but not in the androgen-independent PC3 prostate cancer cell line, indicating that TARP may play a role in prostate cancer progression. To elucidate the function of TARP, we generated a stable PC3 cell line that expresses TARP in a constitutive manner. Expression of TARP in PC3 cells resulted in a more rapid growth rate with a 5-h decrease in doubling time. cDNA microarray analysis of 6538 genes revealed that caveolin 1, caveolin 2, amphiregulin, and melanoma growth stimulatory activity alpha were significantly up-regulated, whereas IL-1beta was significantly down-regulated in PC3 cells expressing TARP. We also demonstrated that TARP expression is up-regulated by testosterone in LNCaP cells that express a functional androgen receptor. These results suggest that TARP has a role in regulating growth and gene expression in prostate cancer cells.
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| 9. |
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