Immune responses to expressed foreign transgenes continue to hamper progress of gene therapy development. Translated foreign proteins with intracellular location are generally less accessible to the immune system, nevertheless they can be presented to the immune system through both MHC Class I and Class II pathways. When the foreign protein luciferase was expressed following intramuscular delivery of plasmid DNA in outbred mice, expression rapidly declined over 4 weeks.
View Article and Find Full Text PDFObjectives: Targeting cytokines to sites of disease has clear advantages because it increases their therapeutic index. We designed fusion proteins of the latent-associated peptide (LAP) derived from TGF-β with various cytokines via a matrix metalloproteinase (MMP) cleavage site. This design confers latency, increased half-life and targeting to sites of inflammation.
View Article and Find Full Text PDFBackground & Aims: Pancreatic ductal adenocarcinoma (PDAC) is characterized by a prominent desmoplastic microenvironment that contains many different immune cells. Activated pancreatic stellate cells (PSCs) contribute to the desmoplasia. We investigated whether distinct stromal compartments are differentially infiltrated by different types of immune cells.
View Article and Find Full Text PDFT-cell exhaustion, originally described in chronic viral infections, was recently reported in solid and hematologic cancers. It is not defined whether exhaustion contributes to T-cell dysfunction observed in chronic lymphocytic leukemia (CLL). We investigated the phenotype and function of T cells from CLL patients and age-matched controls.
View Article and Find Full Text PDFCancer immune evasion is an emerging hallmark of disease progression. We have demonstrated previously that impaired actin polymerization at the T-cell immunologic synapse is a global immune dysfunction in chronic lymphocytic leukemia (CLL). Direct contact with tumor cells induces defective actin polarization at the synapse in previously healthy T cells, but the molecules mediating this dysfunction were not known.
View Article and Find Full Text PDFThe aim of this study was to construct a promoter containing DNA motifs for an endogenous transcription factor associated with inflammation along with motifs for pharmacological regulation factors. We demonstrate in transfected cells that expression of a gene of interest is induced by hypoxic conditions or through pharmacological induction, and also show pharmacological repression. In vivo studies utilised electroporation of plasmid to mouse paws, a delivery method shown to be effective by bioluminescence imaging.
View Article and Find Full Text PDFAn important hallmark of cancer progression is the ability of tumor cells to evade immune recognition. Understanding the relationship between neoplastic cells and the immune microenvironment should facilitate the design of improved immunotherapies. Here we identify impaired T-cell immunologic synapse formation as an active immunosuppressive mechanism in follicular lymphoma (FL) and diffuse large B-cell lymphoma (DLBCL).
View Article and Find Full Text PDFUnderstanding how the immune system in patients with cancer interacts with malignant cells is critical for the development of successful immunotherapeutic strategies. We studied peripheral blood from newly diagnosed patients with acute myeloid leukemia (AML) to assess the impact of this disease on the patients' T cells. The absolute number of peripheral blood T cells is increased in AML compared with healthy controls.
View Article and Find Full Text PDFInhibition of tumour necrosis factor (TNF)-alpha with biological molecules has proven an effective treatment for rheumatoid arthritis, achieving a 20% improvement in American College of Rheumatology score in up to 65% of patients. The main drawback to these and many other biological treatments has been their expense, which has precluded their widespread application. Biological molecules could alternatively be delivered by gene therapy as the encoding DNA.
View Article and Find Full Text PDFConstitutive expression of the inflammatory cytokine tumor necrosis factor-alpha (TNF-alpha) is characteristic of malignant ovarian surface epithelium. We investigated the hypothesis that this autocrine action of TNF-alpha generates and sustains a network of other mediators that promote peritoneal cancer growth and spread. When compared with two ovarian cancer cell lines that did not make TNF-alpha, constitutive production of TNF-alpha was associated with greater release of the chemokines CCL2 and CXCL12, the cytokines interleukin-6 (IL-6) and macrophage migration-inhibitory factor (MIF), and the angiogenic factor vascular endothelial growth factor (VEGF).
View Article and Find Full Text PDFObjective: Collagen-induced arthritis is a commonly accepted model of rheumatoid arthritis (RA). However, it has been difficult to substantiate the involvement of autoimmunity to type II collagen (CII) in the pathogenesis of RA. The aim of this investigation was to determine if CII, modified by reactive oxidant species present within the inflamed joint, could generate neoantigenic epitopes.
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