ABSTRACT
The aim of this study was to determine if human melanoma cells could be molecularly modified by particle-mediated gene transfer with a "gene gun", using genes for interferon-gamma (IFN-gamma), the B7-1 costimulatory molecule (CD80), and human leukocyte antigen (HLA)-A2, to augment expression of both HLA molecules and B7-1. Established and early passage melanoma cells transfected with human IFN-gamma complementary DNA (cDNA) produced IFN-gamma (50-5,000 pg/mL). The biological effect of this IFN-gamma transgene included an upregulation, or de novo appearance, of HLA expression. These melanoma cells had no detectable baseline surface expression of the B7-1 costimulatory molecule, but 8% to 31% of these cells became B7-1 positive with no selection procedure after gene transfer with human B7-1 cDNA. After combination gene transfer with cDNAs for both IFN-gamma and B7-1, 9% to 33% of these cells expressed both HLA-DR and B7-1. In combination gene transfer experiments with cDNAs for both HLA-A2 and B7-1, dual expression of HLA-A2 and B7-1 was achieved in 10% to 17% of the melanoma cells. Thus, the molecular modification of human melanoma cells to increase expression of both HLA and B7-1 can be achieved by particle-mediated gene delivery and presents a promising strategy to stimulate antimelanoma T-cell immunity. Key words: Melanoma; T cells; B7-1 costimulatory molecule (CD80); major histocompatibility complex.
Subject(s)
B7-1 Antigen/biosynthesis , HLA Antigens/biosynthesis , Interferon-gamma/biosynthesis , Melanoma , Transfection/methods , B7-1 Antigen/genetics , Biolistics , Cell Line , DNA, Complementary , Enzyme-Linked Immunosorbent Assay , Flow Cytometry , Gene Expression , Genes, Reporter , Genetic Therapy/methods , HLA-A2 Antigen/biosynthesis , HLA-DR Antigens/biosynthesis , Humans , Interferon-gamma/genetics , Major Histocompatibility Complex , Melanoma/therapy , Plasmids , Recombinant Proteins/biosynthesis , Tumor Cells, Cultured , beta-Galactosidase/biosynthesisABSTRACT
Throughout the integration process, organizations must constantly envision new opportunities, create mechanisms for communication, set goals and build accountabilities at appropriate levels within the organization. Ideally, an integration process will identify and build cultural strengths wherever they are in the organization and minimize the negative impact of change. An integration process that taps the creative, productive potential throughout the organization will not only reap more benefit from the integration process itself, but also will successfully navigate the culture through the rough waters of change.
Subject(s)
Health Facility Merger/organization & administration , Hospital Restructuring/organization & administration , Models, Organizational , Multi-Institutional Systems/organization & administration , Organizational Culture , Decision Making, Organizational , Humans , Organizational Objectives , Planning Techniques , Systems Integration , WisconsinABSTRACT
Therapy of neuroblastoma patients with interleukin (IL)-2 activates effector cells capable of lysing tumor cells in vitro. When tumor cells are pretreated with certain monoclonal antibodies (MoAb), these in vivo activated effectors show augmented tumor lysis via antibody-dependent cellular cytotoxicity (ADCC). This study presents immunological analyses of serial blood samples from two refractory neuroblastoma patients who received combined in vivo therapy with murine anti-ganglioside GD2 monoclonal antibody 14.G2a and IL-2. These studies were designed to determine whether conditions that induce ADCC in vitro can be generated in vivo by combined therapy with IL-2 and MoAb. As shown previously, administration of IL-2 dramatically augments the ability of peripheral blood mononuclear cells (PBMC) to mediate ADCC. In addition, we demonstrate here that sera, obtained 1 h after infusion of 14.G2a, provides an effective source of functional antibody for ADCC mediated by PBMC from healthy donors. Finally, effective ADCC-mediated killing of neuroblastoma target cells was also achieved in vitro following IL-2 plus 14.G2a treatment when patients' effector cells were combined with patients' serum, as the source of 14.G2a antibody. These results indicate that this combination of IL-2 and 14.G2a generates conditions within the peripheral blood of pediatric neuroblastoma patients that enable their own lymphocytes to mediate antibody-dependent cellular cytotoxicity sufficient to effectively kill neuroblastoma cells in vitro.
Subject(s)
Antibodies, Monoclonal/therapeutic use , Antibody-Dependent Cell Cytotoxicity/immunology , Gangliosides/immunology , Immunotherapy/methods , Interleukin-2/therapeutic use , Neuroblastoma/therapy , Cell Line , Child , Child, Preschool , Female , Humans , In Vitro Techniques , Male , Neuroblastoma/immunologyABSTRACT
The design of combination hormonal and immunotherapeutic protocols for breast cancer patients may be facilitated by analysis of preclinical in vitro model systems. Estrogen receptor positive (ER+: MCF-7) and negative (ER-: MDA-MB-231) human breast cancer cell lines were utilized to evaluate the effects of tamoxifen (TAM) and estradiol (E2) on modulation of breast cancer target susceptibility to lysis by lymphokine-activated killer (LAK) cells. E2-stimulated ER+ cells were more susceptible to lysis by LAK cells than corresponding TAM-treated or control cells, while treatment of ER- cells with either E2 or TAM alone did not alter from control their susceptibility to this immune-mediated lysis. All ER+ and ER- cells tested remained sensitive after treatment with TAM to lysis by LAK cells. In addition, an adenocarcinoma reactive human-mouse chimeric monoclonal antibody (ING-1) was able to significantly boost in vivo generated LAK cell-mediated lysis of control, E2-treated, and TAM-treated ER+ and ER- cells. These in vitro results provide a preclinical rationale for in vivo testing of TAM, interleukin-2 (IL-2), and breast cancer reactive antibody-dependent cellular cytotoxicity facilitating antibody in patients with refractory or high risk breast cancer.
