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1.
Clin Diabetes ; 36(2): 100-111, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29686448

RESUMO

IN BRIEF This article reports results from a patient-centered intervention to improve management of type 2 diabetes in the New York City Bangladeshi community. The DREAM (Diabetes Research, Education, and Action for Minorities) intervention is a randomized trial among Bangladeshi immigrants with type 2 diabetes comparing those enrolled in a community health worker (CHW) intervention to those in usual care. Participants in the intervention group received five group-based educational sessions and two one-on-one visits delivered by a trained CHW, whereas those in the control group received only the first group educational session. Main outcomes include changes in A1C, systolic and diastolic blood pressure, cholesterol, triglycerides, weight, BMI, and patient-centered outcomes such as knowledge and behavior related to type 2 diabetes management.

3.
J Exp Med ; 158(1): 240-5, 1983 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-6602860

RESUMO

We investigated the feasibility of generating cytotoxic T cell clones against autologous human melanoma cells using a melanoma cell line (VIP) and a spontaneously transformed autologous fibroblast line (VIP-F:T). Cytotoxic lymphocytes (CL) generated against the VIP melanoma cells in one-way mixed lymphocyte-tumor cell interactions were expanded in interleukin 2 for 2 wk. The expanded CL were cloned in limiting dilution. Two phenotypically homogeneous clones (3:1 and E.5) were obtained bearing OKT3 phenotype. Both clones expressed cytotoxicity selectively only against the sensitizing autologous target VIP. cytotoxicity assays performed with clone E.5 against the VIP target cells in the presence of autologous unfractionated lymphocytes or serum showed no modulation of autoreactivity of clone E.5. These results indicate that analysis of cellular immune response against autologous tumor cells might be feasible using autoreactive clones generated by the currently available in vitro cloning technology.


Assuntos
Melanoma/imunologia , Linfócitos T/imunologia , Anticorpos Monoclonais , Antígenos de Neoplasias/imunologia , Linhagem Celular , Células Clonais/imunologia , Testes Imunológicos de Citotoxicidade , Humanos , Interleucina-2/farmacologia , Fenótipo
4.
J Exp Med ; 169(6): 1961-76, 1989 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-2471770

RESUMO

T cell-mediated immune response against autologous melanoma cells was analyzed, at population and clonal levels, in 31 patients with recurrent and/or metastatic disease. Fresh PBL and lymph node lymphocytes (LNL) from melanoma-involved nodes were not cytotoxic against the respective melanoma cells. When activated in in vitro coculture (IVC) against the autologous melanoma cells in the presence of IL-2, a majority of the activated PBL and LNL became cytotoxic against the autologous targets. The activated effector cells were cloned in limiting dilution microcultures, and growing clones were phenotypically defined and were functionally characterized for cytotoxicity and for potential regulatory function. Functional T cell clones were obtained from 15 of 31 cases. Of these, CTL responses exhibiting cytotoxicity restricted against the autologous melanoma were seen in four cases. All four CTL clones were CD3+, CD8+, and CD4-. Three of these four CTL clones were studied extensively. All three of these CTL clones expressed MHC class I-restricted cytotoxicity. mAb anti-CD3 blocked cytotoxicity in two and enhanced cytotoxicity in the other. Neither autologous sera nor autologous nonactivated fresh PBL modulated the cytotoxic functions of the CTL clones at the effector phase. T cell lines exhibiting regulatory function were obtained in 11 cases. The regulatory T cell lines were CD3+, CD4+, and CD8-. In three cases CD4+ clones amplified the cytotoxic response in the PBL in coculture, while in eight other cases the T cell lines downregulated the cytotoxic responses. Such T cell-mediated down-regulations were either restricted to the autologous system, induced by D/DR antigens expressed by the autologous or allogeneic melanoma cells, or induced by stimulus other than D/DR antigens. Taken together, these findings clearly demonstrate the existence of T cell-mediated cytotoxic and regulatory responses against human melanoma.


Assuntos
Células Clonais/imunologia , Testes Imunológicos de Citotoxicidade , Melanoma/imunologia , Linfócitos T Citotóxicos/imunologia , Linfócitos T/imunologia , Antígenos de Neoplasias/imunologia , Linhagem Celular , Sobrevivência Celular , Células Clonais/fisiologia , Testes Imunológicos de Citotoxicidade/métodos , Citotoxicidade Imunológica , Epitopos/imunologia , Humanos , Interferon gama/fisiologia , Interleucina-2/fisiologia , Antígenos Específicos de Melanoma , Proteínas de Neoplasias/imunologia , Linfócitos T/fisiologia , Linfócitos T Citotóxicos/fisiologia , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Reguladores/imunologia
5.
Science ; 181(4098): 440-2, 1973 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-4577921

RESUMO

A common antigen (S(2)), initially thought to be uniquely associated with human sarcomas, has been found to be widely distributed in patients with other tumors as well. Absorption studies with human embryonic tissues suggest that S(2) may be a fetal antigen. The presence of antibody to S(2) in patients with tumors and in their relatives implies a propensity in these individuals for cellular dedifferentiation which may be a prerequisite for malignant transformation.


Assuntos
Antígenos de Neoplasias/análise , Feto/imunologia , Sarcoma/imunologia , Anticorpos Antineoplásicos/análise , Doenças Autoimunes/imunologia , Neoplasias Ósseas/imunologia , Neoplasias da Mama/imunologia , Carcinoma/imunologia , Células Cultivadas , Embrião de Mamíferos/imunologia , Feminino , Fibrossarcoma/imunologia , Imunofluorescência , Neoplasias Gastrointestinais/imunologia , Tumores de Células Gigantes/imunologia , Doença de Hodgkin/imunologia , Humanos , Leucemia Linfoide/imunologia , Leucemia Mieloide Aguda/imunologia , Lipossarcoma/imunologia , Neoplasias Pulmonares/imunologia , Linfoma/imunologia , Melanoma/imunologia , Osteossarcoma/imunologia , Neoplasias Ovarianas/imunologia , Pele/imunologia
6.
J Clin Invest ; 75(4): 1162-8, 1985 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3988936

RESUMO

Cytotoxic immune response by autologous natural killer (NK) cells against a spontaneous in vitro transformed tumorigenic fibroblast line, VIP-F:T, was studied in a 4 h 51Cr-release microcytotoxicity assay and in a tumor cell neutralization technique in vivo in nude mice. Although highly cytotoxic against the NK prototype target K562, the autologous NK cells in their nascent state were only marginally cytotoxic against VIP-F:T and unreactive against the autologous normal fibroblasts, Pen-F2. Autologous NK activity against VIP-F:T could, however, be induced by 2-16-h treatment of the NK cells with several species of interferon and by interferon-free interleukin 2 (IL-2). In vitro co-culture (IVC) in IL-2 of autologous peripheral blood lymphocytes (PBL) against VIP-F:T was shown by fluorescence activated cell sorting and by cold target competition experiments to generate almost exclusively an effector population bearing HNK-1 and Leu-11a phenotypes which exhibited receptor specificity for VIP-F:T distinct from receptors on Pen-F2 or K562 cells. PBL, co-cultured in IL-2 against Pen-F2 or K562, or cultured in IL-2 alone, generated high levels of nonspecific killing and showed no receptor specificity. Identical IVC in IL-2 of autologous PBL against a melanoma line, VIP (PBL and the VIP line derived from the same patient from whom the VIP-F:T line was also derived), and similar IVC in IL-2 of several other autologous PBL against their corresponding target cell lines (established from surgical specimens) generated cytotoxic responses involving cytotoxic populations bearing T8 as well as HNK-1 phenotypes; but the cytotoxic activities in none of these systems showed target receptor specificity. Autologous PBL, co-cultured against VIP-F:T in IL-2, were shown to be capable of rejecting tumorigenic challenge with VIP-F:T.3 (a clone of VIP-F:T) in nude mice at effector to VIP-F:T ratio of 10:1. The protective effect of the co-culture activated PBL was abrogated if the HNK-1+ cells were depleted from the effector population. Our data, thus, demonstrate specificity of cytotoxic reactivity which, by phenotypic markers, can be characterized as HNK-1 and Leu 11a+ cells under these experimental conditions against this particular in vitro transformed VIP-F:T line. In addition, this study shows that similar studies of cytotoxic autologous reactivities against in vitro transformed target cell lines will provide valuable information on the subject of NK-mediated surveillance against human neoplasia.


Assuntos
Citotoxicidade Imunológica , Células Matadoras Naturais/imunologia , Neoplasias Experimentais/imunologia , Animais , Linhagem Celular , Transformação Celular Neoplásica , Feminino , Fibroblastos , Camundongos , Camundongos Endogâmicos , Transplante de Neoplasias , Fenótipo
7.
J Natl Cancer Inst ; 73(3): 583-93, 1984 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6590910

RESUMO

The establishment of a spontaneously transformed tumorigenic human fibroblast line, VIP-F:T, is described. This line was developed from a primary culture of normal skin from a donor from whom a separate nontransformed fibroblast line, Pen-F2, also was established. The transformed line VIP-F:T exhibited aneuploid karyotype with a marker chromosome, showed anchorage-independent growth, and produced progressively growing tumors with morphologic characteristics of sarcoma in CD-1 (nu/nu) nude mice. The normal fibroblast line Pen-F2 exhibited diploid karyotype, showed no anchorage-independent growth, and produced no tumors in the nude mice. The spontaneously transformed fibroblast line VIP-F:T and its normal counterpart Pen-F2 will be valuable in studies of oncogene expression and in other investigations relevant to neoplasia.


Assuntos
Transformação Celular Neoplásica , Pele/citologia , Divisão Celular , Linhagem Celular , Células Cultivadas , Fibroblastos/citologia , Fibroblastos/ultraestrutura , Antígenos HLA/análise , Humanos , Cariotipagem , Microscopia Eletrônica , Microscopia Eletrônica de Varredura
8.
Cancer Res ; 58(7): 1363-6, 1998 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-9537230

RESUMO

The existence of CD8+ CTLs that are capable of recognizing MHC class I-bound, human tumor-associated peptide antigens is now unequivocally documented in cancer patients. Thus far, the role of CD8+ T cells in tumor immunity has been predominantly viewed in terms of cytolytic ability as the prime mode of their function. Interestingly, it is increasingly evident that CD8+ T cells are capable of synthesizing both type I and type II cytokines. Thus, it is conceivable that tumor antigen-specific but noncytolytic CD8+ T cells might play an important role in antitumor immune response by synthesizing type I cytokine. Through such cytokines, they could provide "help" for the process of generating as well as in maintaining an effective CD8+ CTL response. In addition, they might recruit other types of effector cells (such as natural killer cells, macrophages, and others) locally at the tumor site. Either way, they could exert a profoundly positive role in cell-mediated antitumor immune response, particularly because the great majority of tumor cells express only MHC class I molecules that present peptide epitopes to CD8+ T cells. Unfortunately, tumor antigen-specific, noncytolytic but type I cytokine-secreting CD8+ T cells have not received much investigative attention. Here we show that CD8+ T cells, isolated from the tumor-infiltrating lymphocytes from human melanoma, synthesize type I cytokine (IFN-gamma and tumor necrosis factor alpha) in a MHC class I-restricted and tumor-specific noncytolytic interaction with the autologous melanoma cells.


Assuntos
Antígenos de Neoplasias/imunologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Citocinas/biossíntese , Melanoma/imunologia , Proteínas de Neoplasias/imunologia , Células Th1/metabolismo , Humanos , Interleucina-1/farmacologia , Linfonodos/patologia , Antígenos Específicos de Melanoma , Sensibilidade e Especificidade , Células Tumorais Cultivadas
9.
Cancer Res ; 35(12): 3721-30, 1975 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1192430

RESUMO

In vitro cell-mediated cytotoxicity (CMC) assays have been carried out in human melanoma system with blood effector lymphocytes on [3H]proline-labeled target cells in a 48-hr microcytotoxicity technique. Three lymphocyte purification procedures (Ficoll:Hypaque gradient, plasma gel sedimentation followed by nylon column incubation, and plasma gel sedimentation followed by separation with nylon powder and glass beads) are compared in parallel experiments for characteristic effector cell composition and cytotoxic potential against target cells of dissimilar histology. The cytotoxicity is defined by the loss of target cell 3H cpm as measured by residual target cell 3H cpm in individual microwell following incubation with lymphocytes. Target cell 3H cpm loss by test lymphocytes is compared with target cell 3H cpm loss by several age and sex matched control lymphocytes (from normal donors and unrelated cancer patients); further comparison between the various control lymphocytes is also made in each assay. As control for target cells, autologous fibroblasts and homologous tumor cells of dissimilar histology are always included in each assay. Specific cytotoxicity is defined as statistically significant and selective destruction of only melanoma cells by the test lymphocytes as compared to the control lymphocytes. Significant but nonselective destruction of 2 or more target cells of unrelated histology is regarded as nonspecific cytotoxicity, while no destruction of any target cells signifies no cytotoxicity. The Ficoll:Hypaque preparations consistently exhibit the highest nonlymphocytic cell contamination (8 to 16%); the nonlymphocytic cells are, almost exclusively, monocytes. They also produce relatively high percentage of thymus independent (B) cells (8 to 15%). The ultimate cell composition of the 2 plasma gel-nylon preparations is essentially identical. In either plasma gel-nylon preparations, the nonlymphocytic contamination is minimal (0 to 4%) and thymus-dependent (T) cell percentage is considerably higher (92 to 99%) with none or few B cells.


Assuntos
Testes Imunológicos de Citotoxicidade , Linfócitos/imunologia , Melanoma/imunologia , Separação Celular/métodos , Técnicas de Cultura , Humanos
10.
Cancer Res ; 58(23): 5305-9, 1998 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-9850054

RESUMO

Both CD8+ and CD4+ T cells have demonstrated roles in antitumor immune response in many animal tumor systems. In many human tumor systems, although abundant literature exists on the evidence of tumor antigen-specific CD8+ CTL response, only limited information is available on tumor antigen-specific CD4+ T-cell response. Using the MART-1/Melan-A (MART-1) antigen system as a prototype human tumor-associated antigen (TAA)- and dendritic cell (DC)-based MART-1 antigen presentation system (i.e., DCs transduced with an adenoviral vector-based construct carrying the MART-1 gene), we explored, in vitro, the feasibility of generating both CD8+ and CD4+ T-cell responses in the same individual. Here, we show that autologous DCs from both HLA-A2-positive melanoma patients and normal healthy individuals that are transduced with an adenoviral vector containing the MART-1 antigen are capable of inducing both MART-1-specific CD8+ and CD4+ T cells in in vitro coculture. After several rounds of stimulation, both the CD4+ and CD8+ T cells synthesized IFN-gamma when they were specifically stimulated. The CD8+ T cells generated in such cocultures also recognized the MART-1(27-35) peptide, AAGIGILTV, in 4-h cytotoxicity assays. These observations, therefore, suggest that Th1-type responses can be generated, in vitro, by stimulation with DCs that are genetically modified to express a TAA. Although the outcome of this type of genetically engineered DC-based stimulation may vary from system to system, this type of in vitro antigen presentation may be very useful in more comprehensive analyses of CD4+ T-cell response to defined TAAs, and such genetically engineered autologous DCs might be better candidates to serve as surrogate cancer vaccines.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Proteínas de Neoplasias/imunologia , Antígenos de Neoplasias , Comunicação Celular/fisiologia , Células Dendríticas/metabolismo , Células Dendríticas/fisiologia , Epitopos/imunologia , Epitopos de Linfócito T/imunologia , Humanos , Ativação Linfocitária/fisiologia , Antígeno MART-1 , Melanoma/imunologia , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Transdução Genética
11.
Cancer Res ; 56(11): 2479-83, 1996 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-8653680

RESUMO

Identification of human melanoma-associated peptide antigens for CTLs has opened unprecedented opportunities for active specific immunotherapy for melanoma with synthetic peptide. We have shown that immunization with a MAGE-1 gene encoded nonapeptide (EADPT-GHSY)-pulsed autologous antigen presenting cell-based vaccine induces autologous melanoma-reactive and peptide-specific CTL response, in situ, at the vaccination site and at distant tumor deposits in patients who are HLA-A1+ and whose melanoma cells express the MAGE-1 mRNA. Here, we show that such immunization is also capable of increasing the frequency of autologous melanoma-reactive CTL precursors in the circulation. We further show that in vitro stimulation of the postimmunization peripheral blood lymphocytes with the MAGE-1 nonapeptide-loaded antigen presenting cell and interleukin-2 leads to significant expansion of peptide-specific and autologous melanoma-reactive CTL response.


Assuntos
Antígenos de Neoplasias/imunologia , Melanoma/imunologia , Proteínas de Neoplasias , Linfócitos T Citotóxicos/imunologia , Sequência de Aminoácidos , Células Apresentadoras de Antígenos/imunologia , Citotoxicidade Imunológica , Humanos , Imunização , Antígenos Específicos de Melanoma , Dados de Sequência Molecular , Peptídeos/química , Peptídeos/imunologia , Fator de Necrose Tumoral alfa/biossíntese , Vacinas/imunologia
12.
J Immunol Methods ; 37(3-4): 233-47, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-7451996

RESUMO

The [3H]proline microcytotoxicity technique has been adopted to examine the spontaneous cytotoxic property of human circulating monocytes (M) derived from the peripheral blood and resident monocytes/macrophages (M0) derived from effusion fluids. A leukocyte fraction is obtained by centrifugation in Ficoll-Hypaque (F-H) gradient. M are then isolated as adherent cells following incubation of the leukocyte fraction in plastic flasks containing 50% fetal calf serum (FCS) in culture medium. M0 are isolated from effusion fluids after first separating the Fc receptor bearing cells (as Fc receptor-7S EA resettes) in F-H gradient and then enriching them as adherent cells. The above techniques yield a M/M0 population of some 90-98% purity. The M/M0 non-selectively lyse tumor cells and allogeneic normal fibroblasts in the 48 h [3H]proline assay. The fibroblasts, however, exhibit considerable resistance to lysis, particularly at lower effector to target ratios. While appreciable levels of cytotoxicity are observed with resident M0 at 6 h, followed by a further increase in the level of cytotoxicity at 24-48 h, circulating M exhibit a consistent level of cytotoxicity only at 24-48 h. When circulating M and resident M0 from the same donor are examined concurrently for cytotoxicity, resident M0 are consistently found to show significantly higher levels of cytotoxicity when compared to circulating M. This may reflect a true functional heterogeneity within this lineage of effector cells or some degree of in vivo activation of resident M0 in malignant and non-malignant effusion fluids. Further studies of spontaneous cytotoxicity by M/M0 through CMC assay techniques, such as the [3H]proline microtoxicity technique, will be useful in the examination of the role of M/M0 in cell mediated immunity and immunosurveillance against cancer.


Assuntos
Testes Imunológicos de Citotoxicidade/métodos , Leiomiossarcoma/imunologia , Macrófagos/imunologia , Melanoma/imunologia , Monócitos/imunologia , Linhagem Celular , Citotoxicidade Imunológica , Humanos , Neoplasias Experimentais/imunologia
13.
Am J Med ; 70(4): 803-7, 1981 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7211917

RESUMO

The ectopic secretion of prolactin by neoplasms has been reported only rarely although in one preliminary report it has been found to be present commonly in tumor extracts. To ascertain whether this is due to a true rarity of prolactin-secreting tumors or to the fact that prolactin hypersecretion causes few notable clinical symptoms in patients with cancer, we measured prolactin levels by radioimmunoassay in the serums of 215 patients who had a variety of malignancies. Prolactin levels were elevated (greater than 25 ng/ml) in 15 patients. In 12 of these 15 patients, the elevations could be explained by the use of phenothiazine or opiates, or prior irradiation to the chest wall or head. Additional serum samples showed clearly normal prolactin levels in one of the patients. Of the entire series of 215 patients, therefore, only two patients (1 percent) had modestly elevated prolactin levels without having known causes for hyperprolactinemia: one patient with squamous cell carcinoma of the lung (prolactin 34.1 ng/ml) and one patient with breast cancer (prolactin 45.4 ng/ml). Even in these two patients the hyperprolactinemia could as likely be due to stimulation of afferent nerves in the chest wall as to ectopic secretion by the tumors. There is no clear evidence in our study or in the literature that prolactin is secreted ectopically; this is in sharp contrast to many studies showing the high frequencies of the ectopic secretion of a number of other hormones. Why this is so is unknown.


Assuntos
Neoplasias/metabolismo , Prolactina/metabolismo , Humanos , Masculino , Neoplasias/sangue , Prolactina/sangue , Radioimunoensaio , Valores de Referência
14.
Immunol Lett ; 23(2): 149-54, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2576655

RESUMO

Two autologous T cell lines infected with HTLV I are described. T cells from a patient with malignant melanoma were infected with HTLV I by co-culture with a HTLV I-producing T cell line, SLB I. Both T cell lines express identical phenotype (CD3+, CD4+, 4B4+, 2H4-) but they demonstrate marked differences in growth characteristics and function. One of these two lines, referred to as TFTx, established from the autologous tumor activated peripheral blood lymphocytes (PBL), grows in culture without any exogenous interleukin-2 (IL-2), secretes no detectable amount of IL-2 or gamma interferon (IFN) or tumor necrosis factor (TNF) alpha or beta. The other line (TFATx), established from a co-culture between the autologous PBL, lethally irradiated TFTx and the autologous melanoma cells TF-M, is IL-2-dependent for growth, secretes IFN gamma and TNF alpha and beta. TFTx exerts profound suppression of generation of cytotoxicity in the autologous PBL in co-culture with the autologous melanoma cells TF-M. In contrast, the TFATx enhances the cytotoxic response in similar co-culture. In addition to suppression of cytotoxic response, supernatant from TFTx suppresses the lectin-activated proliferation of PBL. In 4-h chromium release microcytotoxicity assays, neither line exhibits conventional characteristics of cytotoxic cells. Thus, phenotypically identical HTLV I-infected CD4+ T cell lines derived from the same individual exhibit opposite regulatory functions.


Assuntos
Linfócitos T CD4-Positivos/microbiologia , Vírus Linfotrópico T Tipo 1 Humano , Linfócitos T CD4-Positivos/imunologia , Linhagem Celular Transformada , Citotoxicidade Imunológica , Humanos , Melanoma/patologia , Fenótipo , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Auxiliares-Indutores/microbiologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/microbiologia
15.
Immunol Lett ; 28(2): 155-9, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-1679414

RESUMO

Twelve autologous mixed peripheral blood (PBL) tumor cell interactions (MLTC) followed by in vitro expansion of the stimulated T cells in recombinant interleukin-2 (IL-2) were analyzed for the potential emergence of oligoclonal or monoclonal T cell populations in the PBL by Southern blot analysis of the T cell receptor (TCR) beta gene. The emergence of oligoclonal or monoclonal TCR beta gene rearranged populations was seen in 5 of the 12 cases. In 2 of these 5 cases only one dominantly rearranged band was observed. The emergence of oligoclonal or monoclonal T cell populations following stimulation with autologous melanoma cells was associated with predominant CD4 phenotype of the stimulated PBL exhibiting a varied degree of cytotoxicity toward the respective autologous melanoma cells. The evidence of emergence of monoclonal or oligoclonal T cell populations following stimulation with autologous tumor cells strongly supports the existence of T cell-mediated responses against autologous melanomas. Furthermore, cellular and molecular analyses of T cell responses in autologous mixed lymphocyte tumor cell interactions will provide valuable information on the nature of the T cell responses and on the pattern of gene segment usages by the T cells in response to the autologous tumor cells.


Assuntos
Rearranjo Gênico da Cadeia beta dos Receptores de Antígenos dos Linfócitos T , Interleucina-2/farmacologia , Melanoma/imunologia , Receptores de Antígenos de Linfócitos T/genética , Subpopulações de Linfócitos T/patologia , Antígenos de Diferenciação de Linfócitos T/análise , Antígenos CD4/análise , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/patologia , Antígenos CD8 , Células Clonais/efeitos dos fármacos , Humanos , Teste de Cultura Mista de Linfócitos , Melanoma/patologia , Receptores de Antígenos de Linfócitos T alfa-beta , Subpopulações de Linfócitos T/efeitos dos fármacos , Subpopulações de Linfócitos T/imunologia
16.
Immunol Lett ; 35(1): 51-7, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8458636

RESUMO

Recently, there has been a surge of interest in gene therapy in cancer particularly with cytokine transduced tumor cells as a novel form of tumor vaccine. In two autologous human tumor systems, using the tumor cells engineered to produce interleukin-2 by gene transduction techniques, we have examined whether or not such genetically altered cells are capable of inducing a tumor specific cytolytic T cell (CTL) response, in vitro, in co-culture with the respective autologous peripheral blood lymphocytes (PBL). We found that in neither system did co-cultures of the IL-2 producing tumor cells and the autologous PBL generate much cytolytic effector cell activity directed against the respective tumor cells, although these co-cultures did lead to the generation of substantial levels of natural killer (NK) cell activity when measured against the prototype NK sensitive target K562 line. More surprisingly, the levels of lymphokine activated killer cell responses against the respective autologous targets that could be generated in the PBL with exogenous IL-2 alone were compromised by the presence of the autologous tumor cells in the co-culture.


Assuntos
Citotoxicidade Imunológica , Interleucina-2/biossíntese , Neoplasias/imunologia , Antígenos de Neoplasias , Autoantígenos , Engenharia Genética , Terapia Genética , Humanos , Técnicas In Vitro , Interleucina-2/genética , Isoantígenos , Células Matadoras Ativadas por Linfocina/imunologia , Células Matadoras Naturais/imunologia , Neoplasias/terapia , Linfócitos T Citotóxicos/imunologia , Células Tumorais Cultivadas/imunologia
17.
Am J Cardiol ; 63(11): 702-8, 1989 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-2646896

RESUMO

The possibility of discontinuing--compared to reducing--antihypertensive drug treatment was investigated in 606 male hypertensive patients with entry diastolic blood pressure (BP) in the range of 90 to 114 mm Hg. Diastolic BP was controlled at less than 90 mm Hg with 1 of 4 regimens: low dose hydrochlorothiazide (HCTZ), 25 mg twice daily; high dose HCTZ, 50 mg twice daily; or high dose HCTZ plus a low or high dose of a step II drug (propranolol, clonidine or reserpine). After 6 months of treatment that controlled BP, dosages were reduced in two-thirds of the patients. In those patients receiving low dose HCTZ and randomized to dose reduction, antihypertensive drugs were completely discontinued. Although approximately half of these patients remained normotensive for the first 6 months, a significantly greater proportion had elevation of BP compared to the control group, which continued to receive treatment (p less than 0.0001). In the high dose HCTZ drug group, the proportion of patients remaining normotensive did not differ among those stepped down to low dose HCTZ and the fully treated control group. While not achieving significance the trend was similar with the step II regimens. Although some patients remained normotensive after discontinuation of step II drugs, a greater proportion returned to elevated BP than when step II dosage was unchanged. Therefore, while stopping therapy may be effective in some patients, a decreased dosage is significantly more effective as a method for maintaining an antihypertensive effect. Decreasing drug dosages offers the dual benefit of minimizing side effects and reducing drug costs.


Assuntos
Anti-Hipertensivos/administração & dosagem , Hipertensão/tratamento farmacológico , Anti-Hipertensivos/uso terapêutico , Ensaios Clínicos como Assunto , Clonidina/administração & dosagem , Esquema de Medicação , Seguimentos , Humanos , Hidroclorotiazida/administração & dosagem , Masculino , Propranolol/administração & dosagem , Distribuição Aleatória , Reserpina/administração & dosagem , Fatores de Tempo
18.
Biochem Pharmacol ; 37(19): 3761-4, 1988 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-3178889

RESUMO

The bile duct was cannulated in rats that had been infused intravenously with an emulsion of perfluorodecalin at intervals from 2 to 34 weeks earlier. After injection of [14C]phenobarbital, urine and bile were collected during the next 24 hr and were analyzed for phenobarbital and its metabolites. There was a decrease in the biliary excretion of phenobarbital and its metabolites for several weeks after infusion of perfluorodecalin, but conjugation of the metabolites was not decreased. The reduced excretion returned to normal after about 20 weeks.


Assuntos
Fluorocarbonos/farmacologia , Fígado/metabolismo , Fenobarbital/metabolismo , Animais , Bile/metabolismo , Hidroxilação , Fígado/efeitos dos fármacos , Masculino , Ratos , Ratos Endogâmicos
19.
Invest Radiol ; 28(8): 710-9, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8376003

RESUMO

RATIONALE AND OBJECTIVES: In-vivo assessment of tumor vascular volume may provide useful information for treatment planning or the assessment of treatment effectiveness. The goals of our study were to measure percent vascular volume in two experimental tumor sublines using 19F magnetic resonance imaging (MRI) and to assess changes in tumor blood volume with growth. METHODS: An emulsion of perfluorotributylamine (FTBA) was used as a vascular contrast agent for 19F MRI: The amount of emulsion in the tumor vasculature was measured by 19F MRI and used to calculate percent vascular volume. A separate ex-vivo study of vascular volume was conducted using the dye Hoechst 33342. A total of five rats were studied by MRI and 14 by the ex-vivo method. RESULTS: The ranges of percent vascular volume values measured in the imaging and Hoechst dye studies were 2% to 9% and 1.25 to 7%, respectively. A trend toward decreasing percent vascular volume with increasing tumor volume was evident in one tumor subline. CONCLUSIONS: The quantitative 19F MRI technique was effective for measuring percent vascular volume and changes in vascular volume with growth.


Assuntos
Adenocarcinoma/irrigação sanguínea , Adenocarcinoma/diagnóstico , Flúor , Imageamento por Ressonância Magnética/métodos , Neoplasias da Próstata/irrigação sanguínea , Neoplasias da Próstata/diagnóstico , Animais , Benzimidazóis , Substitutos Sanguíneos , Calibragem , Corantes Fluorescentes , Fluorocarbonos , Imageamento por Ressonância Magnética/instrumentação , Masculino , Modelos Estruturais , Transplante de Neoplasias , Ratos , Células Tumorais Cultivadas
20.
Invest Radiol ; 27(8): 620-7, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1428740

RESUMO

RATIONALE AND OBJECTIVES: Emulsions of perfluorocarbons (PFCs) have been tested as blood substitutes. However, evidence exists that there is long-term retention of some PFCs by the organs of the reticuloendothelial system (RES). The authors investigate organ retention of the blood substitute component, perfluorotripropylamine (FTPA), using fluorine-19 (19F) magnetic resonance imaging (MRI). METHODS: Various dosages of an emulsion of FTPA were administered to five rats. At intervals up to 86 weeks after infusion, 19F MRI was used to measure the amount of FTPA in liver and spleen. The data were fit to both linear and exponential elimination models, and organ retention half-lives were calculated. RESULTS: The exponential half-lives for combined liver and spleen FTPA ranged from 110 to 190 days. Linear half-lives ranged from 175 to 300 days. CONCLUSIONS: FTPA retained by the liver and spleen may be quantified by 19F MRI: The half-lives that were measured are longer than those reported previously for FTPA.


Assuntos
Substitutos Sanguíneos/farmacocinética , Flúor , Fluorocarbonos/farmacocinética , Imageamento por Ressonância Magnética/métodos , Animais , Emulsões , Meia-Vida , Fígado/anatomia & histologia , Fígado/metabolismo , Imageamento por Ressonância Magnética/instrumentação , Ratos , Ratos Sprague-Dawley , Baço/anatomia & histologia , Baço/metabolismo , Fatores de Tempo
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