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Biomedical subjects

J D Wolchok

Publications and source records attributed to J D Wolchok.

14 recordsLinked to original sources
PubMed2000

Immunization with DNA coding for gp100 results in CD4 T-cell independent antitumor immunity.

BACKGROUND: Xenogeneic DNA immunization can exploit small differences in expressed protein sequence resulting in immune recognition of self-molecules. We hypothesized that immunizing mice with xenogeneic DNA coding for the human melanosomal membrane glycoprotein gp100 would overcome immune ignorance or tolerance and result in tumor immunity. We also investigated the immunologic mechanisms of the antitumor immunity. METHODS: C57BL/6 mice were immunized with DNA coding for human gp100, mouse gp100, or control vector by gene gun. After immunization, mice were challenged with a syngeneic melanoma expressing gp100, and tumor growth was analyzed. Mice deficient in major histocompatibility complex class I or class II molecules were similarly studied to assess the immunologic mechanism of the tumor protection. RESULTS: There was significant tumor protection after vaccination with xenogeneic human gp100 DNA. Class I, but not class II, major histocompatibility complex molecules were required for tumor immunity. In addition, mice immunized with human gp100 demonstrated autoimmunity manifested as coat color depigmentation. CONCLUSIONS: Immunization with xenogeneic DNA coding for the melanosomal glycoprotein gp100 results in tumor protection and autoimmune depigmentation. These results show that xenogeneic DNA vaccines can lead to cancer immunity without CD4(+) T-cell help with potential implications for rational vaccine design.

Amino Acid Sequence↗
PubMed2000

Management of renal cell carcinoma.

Surgical resection remains the cornerstone of management for localized renal cell carcinoma. No effective postsurgical adjuvant therapy has been established for patients with locally advanced disease who are at high risk for recurrence. The effective treatment of metastatic kidney cancer remains a challenge. Immunologic therapy with cytokines, such as interferon-alfa (Intron A, Roferon-A) and interleukin-2 (IL-2 [Proleukin]), benefit relatively small numbers of patients. Preclinical research and clinical investigations aimed at identifying new agents and treatment programs with improved antitumor activity against metastases remain the highest priorities in this refractory disease. New immunologic approaches to the treatment of both advanced and high-risk postsurgical disease are focusing on novel vaccine therapies to target both renal epithelial and vascular antigens.

Antibodies, Monoclonal↗
PubMed2000

Systemic chemotherapy.

The main use of systemic chemotherapy in metastatic melanoma remains palliative. Dacarbazine (dimethyl-1-triazeno imidazole-4-carboxamide [DTIC]) is the standard chemotherapy agent for advanced disease. The combination chemotherapy and biochemotherapy regimens have achieved higher response rates, but have not led to durable remission or improved survival. The field of systemic therapy remains in need of a more effective and less toxic treatment strategy.

Antineoplastic Agents↗
PubMed1999

Coupling and uncoupling of tumor immunity and autoimmunity.

Self-antigens, in the form of differentiation antigens, are commonly recognized by the immune system on melanoma and other cancers. We have shown previously that active immunization of mice against the melanocyte differentiation antigen, a tyrosinase-related protein (TRP) gp75(TRP-1) (the brown locus protein) expressed by melanomas, could induce tumor immunity and autoimmunity manifested as depigmentation. In this system, tumor immunity and autoimmunity were mediated by autoantibodies. Here, we characterize immunity against another tyrosinase family glycoprotein TRP-2 (the slaty locus protein), using the same mouse model and method of immunization. As observed previously for gp75(TRP-1), immunity was induced by DNA immunization against a xenogeneic form of TRP-2, but not against the syngeneic gene, and depended on CD4(+) cells. Immunization against TRP-2 induced autoantibodies and autoreactive cytotoxic T cells. In contrast to immunization against gp75(TRP-1), both tumor immunity and autoimmunity required CD8(+) T cells, but not antibodies. Only autoimmunity required perforin, whereas tumor immunity proceeded in the absence of perforin. Thus, immunity induced against two closely related autoantigens that are highly conserved throughout vertebrate evolution involved qualitatively different mechanisms, i.e., antibody versus CD8(+) T cell. However, both pathways led to tumor immunity and identical phenotypic manifestations of autoimmunity.

Animals↗
PubMed1999

Injection of DNA encoding granulocyte-macrophage colony-stimulating factor recruits dendritic cells for immune adjuvant effects.

An important issue for effective vaccines is the development of potent adjuvants that can facilitate induction or augmentation of immunity. Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a growth factor for myeloid progenitors of monocytes and dendritic cells (DC), which upon maturation are antigen-presenting cells (APC). The adjuvant effects of inoculation of DNA encoding GM-CSF into skin were studied. Initial experiments examined whether the GM-CSF gene injected into the skin of mice could affect the density of epidermal DC (Langerhans cells). DNA encoding GM-CSF delivered by particle bombardment into skin resulted in a significant increase of epidermal DC at the inoculation site. Kinetic analysis of epidermal recruitment after GM-CSF inoculation showed an increase in DC that peaked at seven days. This increase was accompanied by recruitment of DC into draining lymph nodes. The adjuvant effects of DNA encoding GM-CSF inoculated into skin were measured by the ability to augment antibody and T-cell responses against poorly immunogenic tumor antigens. Peptide immunization at skin sites containing epidermal DC newly recruited by GM-CSF DNA elicited T-cell responses against mutant p53, whereas peptide immunization of control skin sites did not elicit any detectable T-cell responses. Likewise, generation of antibodies following immunization with DNA encoding human gp75TRP1, a tyrosinase family member expressed by melanomas, was accelerated and protection from tumor challenge augmented by GM-CSF DNA.

Adjuvants, Immunologic↗
PubMed1998

Tumor immunity and autoimmunity induced by immunization with homologous DNA.

The immune system can recognize self antigens expressed by cancer cells. Differentiation antigens are prototypes of these self antigens, being expressed by cancer cells and their normal cell counterparts. The tyrosinase family proteins are well characterized differentiation antigens recognized by antibodies and T cells of patients with melanoma. However, immune tolerance may prevent immunity directed against these antigens. Immunity to the brown locus protein, gp75/ tyrosinase-related protein-1, was investigated in a syngeneic mouse model. C57BL/6 mice, which are tolerant to gp75, generated autoantibodies against gp75 after immunization with DNA encoding human gp75 but not syngeneic mouse gp75. Priming with human gp75 DNA broke tolerance to mouse gp75. Immunity against mouse gp75 provided significant tumor protection. Manifestations of autoimmunity were observed, characterized by coat depigmentation. Rejection of tumor challenge required CD4(+) and NK1.1(+) cells and Fc receptor gamma-chain, but depigmentation did not require these components. Thus, immunization with homologous DNA broke tolerance against mouse gp75, possibly by providing help from CD4(+) T cells. Mechanisms required for tumor protection were not necessary for autoimmunity, demonstrating that tumor immunity can be uncoupled from autoimmune manifestations.

Animals↗
PubMed1998

Localized squamous cell carcinoma of the bladder causing hypercalcemia and inhibition of PTH secretion.

We report a case of symptomatic hypercalcemia in a patient with muscle-invasive, resectable squamous cell carcinoma of the bladder. Serum parathyroid hormone was consistent with secretion of parathyroid hormone-related protein. After radical cystoprostatectomy, calcium levels returned to normal. Patients with squamous cell carcinoma and an abnormal serum calcium level may have localized disease and should not be denied definitive local therapy.

Carcinoma, Squamous Cell↗
PubMed1998

Vaccines and other adjuvant therapies for melanoma.

Patients with thick primary melanomas or regional lymph node involvement are at high risk of relapse. Investigations of adjuvant therapy over the past 30 years show only one significantly positive trial employing high dose interferon-alpha-2b. This is a potentially toxic regimen, therefore, other better-tolerated forms of adjuvant immunotherapy are being studied. Recent advances in basic science have led to a better understanding of the T-cell response to human cancer. This article discusses the background and current clinical trials of active specific immunotherapies for melanoma, including peptide and ganglioside vaccines.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1994

Activation of NF-kappa B may be necessary but is not sufficient for induction of H-2 antigens by TNF in J558L murine myeloma cells.

We have investigated the role of the transcription factor NF-kappa B in the induction of H-2 antigens by tumor necrosis factor (TNF) in murine J558L myeloma cells. An earlier report suggested that J558L cells may have a defect in NF-kappa B activation in response to some stimuli. Treatment of J558L cells with either TNF or lipopolysaccharide (LPS) resulted in nuclear translocation of NF-kappa B, as demonstrated by electrophoretic mobility shift assay. Both TNF and LPS activated the same NF-kappa B nuclear complexes, composed of the p50 and p65 subunits. LPS mediated a stronger and more sustained activation of NF-kappa B than TNF. In contrast, TNF induced higher levels of H-2 antigen surface expression than did LPS, suggesting that activation of NF-kappa B is not sufficient for optimal enhancement of H-2 expression. An inhibitor of NF-kappa B activation, pyrrolidinedithiocarbamate (PDTC), dramatically reduced the induction of H-2 antigen by TNF, supporting the view that NF-kappa B is required for TNF-induced H-2 antigen expression. Constitutive levels of H-2 antigen expression on the cell surface and of nuclear NF-kappa B also decreased after PDTC treatment. However, PDTC had a smaller inhibitory effect on LPS-induced NF-kappa B activation and H-2 antigen expression, suggesting that TNF and LPS activate NF-kappa B by somewhat different pathways.

Animals↗
PubMed1992

Critical role of a common transcription factor, IRF-1, in the regulation of IFN-beta and IFN-inducible genes.

Interferon regulatory factor 1 (IRF-1) is a protein that binds to cis-elements within the promoter of interferon (IFN)-beta and some IFN-inducible genes. We used a human fibroblast line, GM-637, to generate stable transfectants constitutively expressing IRF-1 mRNA in either the sense or antisense orientation. Upon induction with poly-(I).poly(C) or Newcastle disease virus, cells expressing sense IRF-1 mRNA produced significantly higher levels of IFN-beta mRNA and protein than control cells, whereas cells expressing antisense IRF-1 mRNA produced little or no IFN-beta mRNA and protein. Furthermore, clear differences were seen among the transfectants in the level of expression of two IFN-induced genes (2'-5'-oligoadenylate synthetase and class I HLA). Our data show that IRF-1 is essential for the induced expression of the IFN-beta gene. The results also indicate an important role of IRF-1 in the expression of IFN-inducible genes and suggest a role for IRF-1 in many other cytokine actions.

2',5'-Oligoadenylate Synthetase↗
PubMed1992

Induction of HLA class I mRNA by cytokines in human fibroblasts: comparison of TNF, IL-1 and IFN-beta.

Expression of HLA class I antigens is known to be regulated by various cytokines at both the mRNA and protein levels. We have examined the induction of HLA-B7 by tumor necrosis factor alpha (TNF), interleukin 1 alpha (IL-1) and interferon beta (IFN-beta) in normal human diploid FS-4 fibroblasts. Optimal induction of HLA-B7 by TNF at 24 h was shown to require a continuous presence of TNF. Since TNF also induces IFN-beta in these cells and the latter cytokine itself has the capacity to upregulate HLA class I expression, we investigated the role of autocrine IFN-beta in the induction of HLA-B7 by TNF. Experiments with neutralizing polyclonal antibodies to recombinant IFN-beta showed that the induction of HLA-B7 mRNA by TNF was partially dependent on autocrine IFN-beta. However, TNF and IFN-beta induced HLA-B7 mRNA with similar kinetics and treatment with saturating concentrations of both TNF and IFN-beta resulted in an additive or possibly synergistic response. The latter findings support the idea that induction of HLA class I by TNF is not mediated solely by autocrine IFN-beta produced in response to TNF. In addition, experiments with the protein synthesis inhibitor cycloheximide suggested that the induction of mRNAs for both the heavy and light (beta 2-microglobulin) chains of the HLA class I antigen by TNF did not require de novo protein synthesis. IL-1 was also shown to increase steady-state mRNA levels of HLA-B7 with kinetics similar to those of TNF and IFN-beta in FS-4 cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Cell Line↗