Angelos D. Gritzapis

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Mesenchymal stem cells (MSCs) are multipotent progenitor cells representing an attractive therapeutic tool for regenerative medicine. They possess unique immunomodulatory properties, being capable of suppressing T-cell responses and modifying dendritic cell differentiation, maturation, and function, whereas they are not inherently immunogenic, failing to(More)
OBJECTIVES The aim of this study was to document the pattern of immune response, assessed by the measurement of both Th1 and Th2 serum cytokines, in patients suffering from autoimmune thyroid disease and toxic nodular goiter. METHODS Both Th1 and Th2 serum cytokine levels were assayed in patients suffering from Graves' disease (GD, n = 25), Hashimoto's(More)
We have recently reported that administration of Pro Tα to DBA/2 mice before the inoculation of syngeneic L1210 leukemic cells prolonged the survival of these animals by (a) inducing tumoricidal peritoneal macrophages, (b) enhancing natural killer (NK) and inducing lymphokine-activated killer (LAK) activities in splenocytes and (c) inducing the production(More)
HER-2/neu is a self-antigen expressed by tumors and nonmalignant epithelial tissues. The possibility of self-tolerance to HER-2/neu-derived epitopes has raised questions concerning their utility in antitumor immunotherapy. Altered HER-2/neu peptide ligands capable of eliciting enhanced immunity to tumor-associated HER-2/neu epitopes may circumvent this(More)
 Peripheral blood mononuclear cells (PBMC) from cancer patients were cultured in vitro with irradiated autologous tumor cells isolated from malignant effusions (mixed lymphocyte tumor cultures, MLTC) and low-dose (50 IU/ml) recombinant interleukin-2 (IL-2). The combination of IL-2 and prothymosin α (ProTα) resulted in a greater PBMC-induced response to the(More)
BALB/c mice transgenic (Tg) for the transforming rat neu oncogene (BALB-neuT) are genetically predestined to develop mammary carcinogenesis in a process similar to that in humans. We crossed HLA-A2.1/HLA-DR1 (A2.1/DR1) Tg mice with BALB-neuT mice to generate A2.1/DR1 x BALB-neuT triple Tg (A2.1/DR1 x neuT(+)) mice, which represent an improvement over(More)
The human HER-2/neu gene encodes a 185 kDa transmembrane glycoprotein recognized by MHC class I-restricted CTLs. Here, we report that HER-2/neu peptide CTL epitopes can also be recognized by cytotoxic NK-T lymphocytes. Unfractionated peptides derived from HLA-A2(+), HER-2/neu(+) tumor cells acid cell extract (ACE), collected from patients with metastatic(More)
The Ii-Key fragment from the MHC class II-associated invariant chain (or Ii protein) has been shown to facilitate direct charging of MHC class II epitopes to the peptide binding groove. The purpose of the present study was to test the potential of a series of Ii-Key/HER-2/neu776-790 hybrid peptides to generate increased frequencies of peptide-specific CD4+(More)
A novel modality toward the treatment of HER-2/neu-positive malignancies, mostly including breast and, more recently prostate carcinomas, has been the use of vaccines targeting HER-2/neu extracellular and intracellular domains. HER-2/neu-specific vaccines have been demonstrated to generate durable T-cell anti-HER-2/neu immunity when tested in Phase I and II(More)
Natural killer (NK) lymphocytes represent the first line of defense against virally infected cells and tumor cells. The role of NK cells in immune responses has been markedly explored, mainly due to the identification of NK cell receptors and their ligands, but also through the analysis of mechanisms underlying the effects of various cytokines on NK cell(More)