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1.
J Clin Oncol ; 12(7): 1475-83, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8021739

RESUMO

PURPOSE: To correlate in vitro characteristics of tumor-infiltrating lymphocytes (TIL) with clinical response to TIL immunotherapy in patients with metastatic melanoma. PATIENTS AND METHODS: Forty-one melanoma patients undergoing 43 separate treatment courses with TIL and interleukin-2 (IL-2) from December 1990 through November 1992 were studied prospectively. Multiple patient and treatment characteristics were evaluated for response correlates. In addition, TIL were assayed within 7 days of infusion for characteristics such as doubling time, cell-surface phenotype, autologous tumor lysis in 4-hour chromium-51 release assays, and cytokine secretion following autologous tumor stimulation. RESULTS: Nine patients experienced complete or partial tumor regressions. Clinical parameters such as age, sex, sites of disease, performance status, and prior therapies were similar in responders and nonresponders. Treatment variables such as the cumulative IL-2 dose and concomitant administration of cyclophosphamide or interferon (IFN)-alpha were not predictive of response, although responders received 33% more TIL. However, statistically significant differences in favor of clinical response were noted for extranodal source of TIL (v lymph node), shorter culture duration (mean, 38 v 47 days), shorter TIL doubling time (2.6 v 3.7 days), greater autologous tumor lysis by TIL (30% v 15%; effector-to-target [E:T], 40:1), and secretion of granulocyte-macrophage colony-stimulating factor (GM-CSF) by TIL following autologous tumor stimulation (six of nine responders v eight of 32 nonresponders). CONCLUSION: The associations of TIL lysis of autologous tumor and younger TIL age with clinical response observed in this study are supportive of previous reports, and these findings will be useful in designing future clinical trials. The new observation correlating GM-CSF secretion by TIL with clinical response is interesting and needs further substantiation.


Assuntos
Imunoterapia/métodos , Interleucina-2/uso terapêutico , Linfócitos do Interstício Tumoral , Melanoma/terapia , Adulto , Feminino , Humanos , Modelos Logísticos , Masculino , Melanoma/secundário , Valor Preditivo dos Testes , Estudos Prospectivos , Resultado do Tratamento
2.
J Immunother Emphasis Tumor Immunol ; 13(4): 282-8, 1993 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-8334112

RESUMO

Tumor-infiltrating lymphocytes (TILs) can mediate tumor regression in selected patients with advanced cancer. To study some of the physiological changes associated with TIL administration, hemodynamic effects were measured while 2 x 10(10) to 20 x 10(10) TILs (mean 10 +/- 1 x 10(10)) were infused into 22 patients. In 10 patients, the first bag of TILs was administered without any interleukin-2 (IL-2) in the infusion bag; subsequent bags in the same patients and all bags in the next 12 patients contained IL-2 in low concentrations (300,000 IU). Two hours following infusion (as compared with baseline), patients developed tachycardia (110 +/- 3.3 vs. 76 +/- 3.5 beats/min; p < 0.001), increased cardiac index (4.9 +/- 0.2 vs. 3.2 +/- 0.13 L/min/m2; p < 0.001), decreased systemic vascular resistance (677 +/- 37 vs. 1185 +/- 63 dyn/s/cm5; p < 0.001), and increased pulmonary artery diastolic pressure (15.9 +/- 1.4 vs. 10.6 +/- 1.1 mm Hg; p = 0.002). No significant changes in systemic blood pressure were noted. Analysis of data obtained in the 10 patients after infusion of the first bag of TILs (4.5 +/- 0.4 x 10(10)) without IL-2 present in the infusate revealed similar, though less severe, changes. No significant correlation was noted between in vitro production of tumor necrosis factor-alpha, interferon-gamma, and granulocyte-macrophage colony-stimulating factor by TILs and hemodynamic effects when administered to patients. These results indicate that TIL infusion can cause hemodynamic changes similar to those previously reported in patients undergoing IL-2 therapy.


Assuntos
Hemodinâmica , Imunoterapia Adotiva , Linfócitos do Interstício Tumoral/imunologia , Neoplasias/terapia , Adulto , Feminino , Humanos , Interleucina-2/uso terapêutico , Masculino , Pessoa de Meia-Idade , Neoplasias/fisiopatologia
3.
J Immunother Emphasis Tumor Immunol ; 13(1): 18-30, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8435428

RESUMO

Lysis of autologous and human leucocyte antigen (HLA)-matched allogeneic melanomas by cultured human tumor-infiltrating leukocytes (TIL) suggests that shared melanoma antigens (Ag) exist and are recognized by TIL in the context of self major histocompatibility complex (MHC) molecules. We have recently shown that cytokine release by TIL is another indicator of the specific interaction with autologous tumor. To determine if recognition of shared melanoma Ag can also induce cytokine release, seven melanoma TIL, which lysed autologous tumor, were co-cultured with autologous tumor or with 7-12 HLA-matched or unmatched melanoma stimulators for 6-24 h. Supernatants were collected and assayed by ELISA for the presence of granulocyte/macrophage colony stimulating factor (GM-CSF), interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, interleukin (IL)-4, and IL-6. Among five of six melanoma TIL for which autologous tumor was available, autologous melanoma cells stimulated specific release of at least one of three cytokines: GM-CSF, IFN-gamma, and TNF-alpha. Neither IL-4 nor IL-6 secretion by three TIL cultures tested was enhanced upon contact with tumor. For six of seven TIL cultures, HLA-matched allogeneic melanomas also stimulated significant cytokine release; HLA-A1, -A2, -A24, -B8, and -Cw7 were identified as possible restriction elements. The cytokine secretion induced by both autologous and allogeneic HLA-matched melanomas could be blocked by an anti-MHC I antibody. These data suggest that cytokines can be specifically released by TIL recognizing a shared melanoma antigen in the context of self MHC molecules.


Assuntos
Fator Estimulador de Colônias de Granulócitos e Macrófagos/análise , Antígenos HLA/imunologia , Interferon gama/análise , Linfócitos do Interstício Tumoral/imunologia , Melanoma/imunologia , Fator de Necrose Tumoral alfa/análise , Citotoxicidade Imunológica , Humanos , Linfócitos do Interstício Tumoral/metabolismo , Células Tumorais Cultivadas
4.
Cancer Immunol Immunother ; 36(1): 1-8, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8422663

RESUMO

Tumor-infiltrating lymphocytes (TIL) were grown in the presence of interleukin-2 from 19 colon carcinoma specimens, including 1 primary lesion and 18 metastatic lesions. These cultures showed a median proliferation of 606-fold (range 13-fold to 28,000-fold) over 49 culture days (range 26-76 days). By phenotype, mature cultures were 69%-99% CD3+ (mean 93%) and contained mixed populations of CD4+ and CD8+ cells (CD4 > CD8 in 10 of 19 cultures). Fresh cryopreserved colon tumors were not lysed by autologous TIL in short-term 51Cr-release assays, and were poorly lysed by lymphokine-activated killer cells. Ten TIL cultures were assayed for cytokine secretion in response to autologous and allogeneic tumors during a 6- to 24-h coincubation. Culture supernatants were tested by ELISA for the presence of granulocyte/macrophage-colony-stimulating factor, interferon gamma, and tumor necrosis factor alpha. Of 10 TIL, 4 secreted at least two of these cytokines specifically in response to autologous and/or HLA-matched fresh allogeneic colon carcinomas, but not to melanomas or HLA-unmatched colon carcinomas. Cytokine secretion was mediated by both CD4+ and CD8+ TIL, and could be inhibited by mAb directed against the appropriate class of MHC antigen. These data provide evidence for specific, MHC-restricted immune recognition of human colon carcinomas by T lymphocytes.


Assuntos
Neoplasias do Colo/imunologia , Citocinas/metabolismo , Ativação Linfocitária/fisiologia , Neoplasias do Colo/patologia , Citotoxicidade Imunológica , Humanos , Imunofenotipagem , Células Matadoras Ativadas por Linfocina , Complexo Principal de Histocompatibilidade , Metástase Neoplásica , Células Tumorais Cultivadas
5.
J Immunother (1991) ; 12(3): 203-6, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1445813

RESUMO

We have established that melanomas express shared tumor antigens (Ags) that can be recognized by T cells if presented in the context of self-MHC molecules. Tumor-infiltrating lymphocytes (TILs) from six melanoma patients were tested for lysis of large panels of HLA-matched or unmatched targets representing a variety of tissue types. Lysis was specific for allogeneic melanomas sharing at least one HLA-A, -B, or -C Ag with TILs, and demonstrated commonly expressed tumor Ags. Similar findings were obtained when cytokine secretion by TILs was used to indicate specific Ag recognition. Transfection of the HLA-A2.1 gene into HLA-A2- melanoma lines conferred susceptibility to lysis by HLA-A2 restricted melanoma TILs, demonstrating expression of common tumor Ags among patients of diverse HLA types. These findings have important implications for developing broadly applicable cancer immunotherapies such as vaccines.


Assuntos
Antígenos de Neoplasias/imunologia , Antígeno HLA-A2/genética , Linfócitos do Interstício Tumoral/imunologia , Melanoma/imunologia , Humanos , Melanoma/terapia , Transfecção , Vacinas
6.
J Immunother (1991) ; 10(3): 153-64, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1868040

RESUMO

Major histocompatibility complex (MHC) class I antigens (Ag), particularly human lymphocyte antigen (HLA)-A2, have been shown to function as restriction elements in human cytotoxic T lymphocyte recognition of tumor. This study was undertaken to determine the function of non-A2 MHC class I Ag in tumor recognition by tumor-infiltrating lymphocytes (TILs) cultured from six melanomas, and to find evidence for shared or unique tumor-associated Ag. Four predominantly CD8+ and two mixed CD4+, CD8+ population TIL cultures were tested for lysis in short-term 51Cr-release assays against a panel of targets including 29 fresh melanomas, 2 fresh sarcomas, 11 cultured melanoma lines, and 14 nonmelanoma cell lines derived from HLA-typed patients. All six melanoma TILs lysed the autologous melanoma. Two of three TILs from HLA-A2+ patients lysed allogeneic melanomas matched for HLA-A2, giving evidence for shared tumor Ag; one of these TILs also used HLA-B44 as a restriction element. The third HLA-A2+ TIL lysed autologous melanoma but not autologous Epstein-Barr virus-transformed B cells nor 14 HLA-A2 matched allogeneic melanomas, suggesting the possibility of a unique tumor Ag in this system. The three HLA-A2- TILs each lysed multiple HLA-matched melanomas, using HLA-A24, HLA-A31, and HLA-Cw7 as restriction elements. Blocking of autologous and allogeneic melanoma lysis by TILs with mAb w6/32 (anti-MHC class I) and anti-CD3, as well as cold target inhibition assays, confirmed that specific interaction of the T-cell receptor with MHC class I Ag and the relevant tumor Ag on the target cell surface is required for tumor lysis. These data provide evidence for specific recognition of shared melanoma Ag by human TILs.


Assuntos
Antígenos de Neoplasias/imunologia , Antígenos HLA/imunologia , Linfócitos do Interstício Tumoral/imunologia , Melanoma/imunologia , Anticorpos Monoclonais/imunologia , Células Cultivadas , Testes Imunológicos de Citotoxicidade , Humanos , Imunofenotipagem , Células Matadoras Ativadas por Linfocina/imunologia , Células Tumorais Cultivadas
7.
Appl Environ Microbiol ; 54(2): 358-63, 1988 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16347549

RESUMO

Twelve Tn5-induced mutants of Bradyrhizobium japonicum unable to grow chemoautotrophically with CO(2) and H(2) (Aut) were isolated. Five Aut mutants lacked hydrogen uptake activity (Hup). The other seven Aut mutants possessed wild-type levels of hydrogen uptake activity (Hup), both in free-living culture and symbiotically. Three of the Hup mutants lacked hydrogenase activity both in free-living culture and as nodule bacteroids. The other two mutants were Hup only in free-living culture. The latter two mutants appeared to be hypersensitive to repression by oxygen, since Hup activity could be derepressed under 0.4% O(2). All five Hup mutants expressed both ex planta and symbiotic nitrogenase activities. Two of the seven Aut Hup mutants expressed no free-living nitrogenase activity, but they did express it symbiotically. These two strains, plus one other Aut Hup mutant, had CO(2) fixation activities 20 to 32% of the wild-type level. The cosmid pSH22, which was shown previously to contain hydrogenase-related genes of B. japonicum, was conjugated into each Aut mutant. The Aut Hup mutants that were Hup both in free-living culture and symbiotically were complemented by the cosmid. None of the other mutants was complemented by pSH22. Individual subcloned fragments of pSH22 were used to complement two of the Hup mutants.

8.
J Bacteriol ; 161(3): 882-7, 1985 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3882669

RESUMO

Recombinant cosmids containing a Rhizobium japonicum gene involved in both hydrogenase (Hup) and nitrogenase (Nif) activities were isolated. An R. japonicum gene bank utilizing broad-host-range cosmid pLAFR1 was conjugated into Hup- Nif- R. japonicum strain SR139. Transconjugants containing the nif/hup cosmid were identified by their resistance to tetracycline (Tcr) and ability to grow chemoautotrophically (Aut+) with hydrogen. All Tcr Aut+ transconjugants possessed high levels of H2 uptake activity, as determined amperometrically. Moreover, all Hup+ transconjugants tested possessed the ability to reduce acetylene (Nif+) in soybean nodules. Cosmid DNAs from 19 Hup+ transconjugants were transferred to Escherichia coli by transformation. When the cosmids were restricted with EcoRI, 15 of the 19 cosmids had a restriction pattern with 13.2-, 4.0-, 3.0-, and 2.5-kilobase DNA fragments. Six E. coli transformants containing the nif/hup cosmids were conjugated with strain SR139. All strain SR139 transconjugants were Hup+ Nif+. Moreover, one nif/hup cosmid was transferred to 15 other R. japonicum Hup- mutants. Hup+ transconjugants of six of the Hup- mutants appeared at a frequency of 1.0, whereas the transconjugants of the other nine mutants remained Hup-. These results indicate that the nif/hup gene cosmids contain a gene involved in both nitrogenase and hydrogenase activities and at least one and perhaps other hup genes which are exclusively involved in H2 uptake activity.


Assuntos
Hidrogenase/genética , Nitrogenase/genética , Rhizobium/genética , DNA Bacteriano/genética , Regulação da Expressão Gênica , Genes Bacterianos , Teste de Complementação Genética , Plasmídeos
9.
J Bacteriol ; 159(1): 335-40, 1984 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6330038

RESUMO

When the "suicide" vector pSUP1011, which carries transposon Tn5 (Kmr), was introduced into Rhizobium japonicum USDA 110, kanamycin-resistant (Kmr) colonies were detected at a frequency (4.2 X 10-6) ca. 30 times greater than the spontaneous kanamycin resistance frequency (1.4 X 10-7). Ten thousand Kmr mutants were isolated and tested for nutritional auxotrophy. Auxotrophs were detected at a frequency of 0.5%. The following classes of auxotrophs were identified: adenine- (three), histidine- (three), glutamate- (five), adenine plus thiamine- (nine), uracil- (three), pantothenic acid- (one), tryptophan- (three), and methionine- (three). Mutants blocked in symbiotic nitrogen fixation (Fix-) were also identified at a frequency of 3%. The glutamate auxotrophs were studied in more detail, and all five showed an altered expression of nitrogenase activity in free-living cultures.


Assuntos
Elementos de DNA Transponíveis , Mutação , Rhizobium/genética , Antibacterianos/toxicidade , Indução Enzimática , Escherichia coli/genética , Genótipo , Nitrogenase/biossíntese , Fenótipo , Plasmídeos , Fatores R , Rhizobium/efeitos dos fármacos , Rhizobium/enzimologia , Especificidade da Espécie
10.
J Bacteriol ; 155(2): 454-8, 1983 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6348020

RESUMO

Under anaerobic conditions, Klebsiella pneumoniae reduced nitrite (NO2-), yielding nitrous oxide (N2O) and ammonium ions (NH4+) as products. Nitrous oxide formation accounted for about 5% of the total NO2- reduced, and NH4+ production accounted for the remainder. Glucose and pyruvate were the electron donors for NO2- reduction to N2O by whole cells, whereas glucose, NADH, and NADPH were found to be the electron donors when cell extracts were used. On the one hand, formate failed to serve as an electron donor for NO2- reduction to N2O and NH4+, whereas on the other hand, formate was the best electron donor for nitrate reduction in either whole cells or cell extracts. Mutants that are defective in the reduction of NO2- to NH4+ were isolated, and these strains were found to produce N2O at rates comparable to that of the parent strain. These results suggest that the nitrite reductase producing N2O is distinct from that producing NH4+. Nitrous oxide production from nitric oxide (NO) occurred in all mutants tested, at rates comparable to that of the parent strain. This result suggests that NO reduction to N2O, which also uses NADH as the electron donor, is independent of the protein(s) catalyzing the reduction of NO2- to N2O.


Assuntos
Klebsiella pneumoniae/metabolismo , Nitritos/metabolismo , Nitrogênio/metabolismo , Óxido Nitroso/metabolismo , Transporte de Elétrons , Klebsiella pneumoniae/genética , Mutação , Oxirredução
11.
J Gen Virol ; 52(Pt 2): 291-9, 1981 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6169784

RESUMO

Polyinosinic acids containing methyl and sulphur substitutions are potent inhibitors of reverse transcriptase. Substitution of sulphur for oxygen at the 6 position produces significant effects on the properties of polyinosinic acid: the kinetics of inhibition change from competitive to mixed-type and the inhibition constant falls by three orders of magnitude. In contrast, 1-methyl substitution produces no such effects. Poly(1-methyl-6-thioinosinic acid) or poly(m1s6I) inhibits irreversibly, inhibiting all ten reverse transcriptases tested under a variety of assay conditions. In cell culture test systems, poly(m1s6I) is capable of blocking both infection by non-transforming viruses and transformation by a sarcoma virus. The presence of poly(m1s6I) in a preinfected culture results in the production of non-infectious virus particles lacking reverse transcriptase activity.


Assuntos
Poli I/farmacologia , Polirribonucleotídeos/farmacologia , Retroviridae/efeitos dos fármacos , Inibidores da Transcriptase Reversa , Tionucleotídeos/farmacologia , Vírus da Mieloblastose Aviária/efeitos dos fármacos , Gammaretrovirus/efeitos dos fármacos , Vírus da Leucemia Felina/efeitos dos fármacos , Retroviridae/enzimologia , Vírus do Sarcoma do Macaco-Barrigudo/efeitos dos fármacos , Relação Estrutura-Atividade , Replicação Viral/efeitos dos fármacos
12.
J Gen Microbiol ; 117(1): 169-79, 1980 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6993623

RESUMO

The rate of biosynthesis of nitrogenase polypeptides in Klebsiella pneumoniae was determined in a medium containing NaNO3 or NaNO2. Nitrogenase biosynthesis was completely repressed by NO3- in a mutant strain, strain SK-25, that is derepressed for nitrogenase biosynthesis in the presence of NH4+. Chlorate-resistant mutants, derived from strain SK-25, that are defective in NO3- respiration produced nitrogenase in the presence of NO3-. Strain SK-56), a chlorate-resistant derivative capable of NO3- respiration, produced no nitrogenase in the presence of NO3- or NO2-. Klebsiella pneumoniae respired under anaerobic conditions utilizing either NO3- or NO2- as terminal electron acceptor. A mechanism for the control of nitrogenase biosynthesis is discussed involving the redox control of anaerobic enzyme systems.


Assuntos
Klebsiella pneumoniae/enzimologia , Nitratos/farmacologia , Nitrogenase/biossíntese , Anaerobiose , Azidas/farmacologia , Eletroforese em Gel de Poliacrilamida , Repressão Enzimática/efeitos dos fármacos , Formiato Desidrogenases/biossíntese , Klebsiella pneumoniae/genética , Mutação , Nitritos/farmacologia
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