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1.
Cancer Immunol Immunother ; 49(8): 449-58, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11043852

RESUMO

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 alpha (ProTalpha) resulted in a greater PBMC-induced response to the autologous tumor than that brought about by IL-2 alone. In particular, ProTalpha specifically enhanced the CD4+ T-cell-mediated proliferation against the autologous tumor. CD4+ T cells seemed to recognize tumor antigens presented by HLA-DR molecules expressed on the autologous monocytes, since preincubation of the latter with an anti-HLA-DR monoclonal antibody (mAb) abrogated the response. In addition, MLTC set up with IL-2 and ProTalpha also generated more MHC-class-I-restricted cytotoxic T lymphocytes (CTL) against the autologous tumor than did MLTC set up with IL-2 alone. The MLTC-induced CTL contained high levels of cytoplasmic perforin and their development was strictly dependent on the presence of both autologous CD4+ T cells and monocytes. In the absence of either population there was a strong impairment of both proliferative and cytotoxic responses which was not restored by the presence of ProTalpha. In contrast, when both cell populations were present, ProTalpha exerted optimal enhancement of CD4+ T cell proliferation, which was associated with potentiated CTL responses. Our data emphasize the role of ProTalpha for the enhancement of IL-2-induced CTL responses against autologous tumor cells. Such responses require collaborative interactions between CD4+, CD8+ T cells and monocytes as antigen-presenting cells. Our data are relevant for adoptive immunotherapeutic settings utilizing IL-2 and ProTalpha-induced autologous-tumor-specific CTL.


Assuntos
Carcinoma/terapia , Interleucina-2/uso terapêutico , Precursores de Proteínas/uso terapêutico , Linfócitos T Citotóxicos/imunologia , Timosina/análogos & derivados , Timosina/uso terapêutico , Idoso , Animais , Neoplasias da Mama/terapia , Complexo CD3/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Bovinos , Comunicação Celular , Divisão Celular/efeitos dos fármacos , Divisão Celular/imunologia , Separação Celular , Células Cultivadas , Feminino , Humanos , Neoplasias Pulmonares/terapia , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Monócitos/metabolismo , Neoplasias Ovarianas/terapia , Fenótipo , Timo/química , Fatores de Tempo , Células Tumorais Cultivadas
2.
Eur J Immunol ; 30(7): 1957-66, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10940885

RESUMO

The response of lymphokine-activated killer (LAK) and natural killer (NK) cells from mice lacking tumor necrosis factor-alpha (TNF-alpha-/- mice) was impaired in cytotoxicity assays against various tumor cell targets. Furthermore, allogeneic cytotoxic T lymphocyte (CTL) responses were also impaired as compared to TNF-alpha+/+ littermates (control mice). Cytotoxicity was restored both upon in vitro incubation of TNF-alpha-/- lymphocytes with recombinant TNF-alpha (rTNF-alpha) or upon in vivo treatment of TNF-alpha-/- mice with rTNF-alpha. Using combinations of monoclonal antibodies we were able to show that TNF-alpha-/- effector lymphocytes exhibit both perforin- and Fas ligand-based cytotoxicity. Furthermore, upon in vivo administration of rTNF-alpha these effectors, in addition to perforin and Fas ligand, are also armed with TNF-alpha cytotoxic molecules, thus resembling to the cytotoxic effectors from control mice. In a tumor model, immunized TNF-alpha-/- mice failed to reject the syngeneic fibrosarcoma MC57X, but did so when injected with rTNF-alpha. In vivo administration of anti-TNF-alpha mAb neutralized the effect of rTNF-alpha supporting the growth of MC57X cells. Our data provide novel evidence for TNF-alpha as an essential factor in (i) controlling cytotoxicity in vitro and in vivo and (ii) promoting tumor rejection in vivo.


Assuntos
Fibrossarcoma/imunologia , Células Matadoras Ativadas por Linfocina/imunologia , Células Matadoras Naturais/imunologia , Linfócitos T Citotóxicos/imunologia , Fator de Necrose Tumoral alfa/imunologia , Animais , Células Cultivadas , Células Dendríticas/citologia , Células Dendríticas/imunologia , Células Matadoras Ativadas por Linfocina/citologia , Células Matadoras Ativadas por Linfocina/efeitos dos fármacos , Células Matadoras Naturais/citologia , Células Matadoras Naturais/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Knockout , Neoplasias Experimentais/imunologia , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/farmacologia , Linfócitos T Citotóxicos/citologia , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/farmacologia
3.
J Immunol ; 164(7): 3902-12, 2000 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10725753

RESUMO

This study focuses on the specific CD4+ T cell requirement for optimal induction of cytotoxicity against MHC class II negative autologous tumors (AuTu) collected from patients with various types of cancer at advanced stages. CD4+ T cells were induced in cultures of cancer patients' malignant effusion-associated mononuclear cells with irradiated AuTu (mixed lymphocyte tumor cultures (MLTC)) in the presence of recombinant IL-2 and recombinant IL-7. Tumor-specific CD4+ T cells did not directly recognize the AuTu cells, but there was an MHC class II-restricted cross-priming by autologous dendritic cells (DCs), used as APC. CD8+ CTL, also induced during the MLTC, lysed specifically AuTu cells or DCs pulsed with AuTu peptide extracts (acid wash extracts (AWE)) in an MHC class I-restricted manner. Removal of CD4+ T cells or DCs from the MLTC drastically reduced the CD8+ CTL-mediated cytotoxic response against the AuTu. AWE-pulsed DCs preincubated with autologous CD4+ T cells were able, in the absence of CD4+ T cells, to stimulate CD8+ T cells to lyse autologous tumor targets. Such activated CD8+ T cells produced IL-2, IFN-gamma, TNF-alpha, and GM-CSF. The process of the activation of AWE-pulsed DCs by CD4+ T cells could be inhibited with anti-CD40 ligand mAb. Moreover, the role of CD4+ T cells in activating AWE-pulsed DCs was undertaken by anti-CD40 mAb. Our data demonstrate for the first time in patients with metastatic cancer the essential role of CD4+ Th cell-activated DCs for optimal CD8+ T cell-mediated killing of autologous tumors and provide the basis for the design of novel protocols in cellular adoptive immunotherapy of cancer, utilizing synthetic peptides capable of inducing T cell help in vivo.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Citotoxicidade Imunológica/imunologia , Epitopos de Linfócito T/imunologia , Ativação Linfocitária/imunologia , Neoplasias/imunologia , Neoplasias/terapia , Linfócitos T Citotóxicos/imunologia , Idoso , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Comunicação Celular/imunologia , Extratos Celulares/imunologia , Citocinas/biossíntese , Células Dendríticas/imunologia , Feminino , Humanos , Imunoterapia Adotiva/métodos , Teste de Cultura Mista de Linfócitos , Masculino , Pessoa de Meia-Idade , Neoplasias/patologia , Ácido Trifluoracético , Células Tumorais Cultivadas
4.
Cancer Immunol Immunother ; 48(2-3): 71-84, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10414460

RESUMO

Anti-CD3 monoclonal antibody (mAb) activates in vitro peripheral blood mononuclear cells (PBMC) to lyse a variety of tumor cell lines in a non-major histocompatibility-complex(MHC)-restricted manner [subsequently referred to as anti-CD3-activated killer (AAK) cytotoxicity]. Prothymosin alpha (ProTalpha) is a biological response modifier that exerts its effects primarily on mononuclear cells, especially when these cells' effector functions are impaired. In this study, we report that ProTalpha enhances the AAK cytotoxicity in PBMC from healthy donors. This effect was more profound with cancer patients' PBMC, which were deficient in their ability to respond with enhanced AAK cytotoxicity upon in vitro stimulation with anti-CD3. Thus, cancer patients' PBMC, activated with a combination of anti-CD3 and ProTalpha, exhibited increased AAK activity and efficiently lysed both autologous tumor and Daudi targets. The ProTalpha effect on PBMC was demonstrated to involve stimulation of adhesion molecules (CD2, CD18, CD54, CD49f) and CD25 expression, up-regulation of perforin mRNA transcription, increased numbers of perforin-positive (+) cells and elevated production of interleukin-2 (IL-2), interleukin-1beta (IL-1beta) and tumor necrosis factor alpha (TNFalpha). Moreover, effector CD8+ and CD56+ cells pretreated with anti-CD3 and ProTalpha contained high cytoplasmic perforin levels and increased expression of IL-1beta- and TNFalpha-specific receptors. The induction of autologous-tumor-reactive CD8+ and CD56+ lymphocytes in anti-CD3-activated PBMC by ProTalpha provides an alternative protocol aimed at the improvement of clinical results in cellular adoptive immunotherapy of cancer.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Complexo CD3/imunologia , Neoplasias/terapia , Precursores de Proteínas/farmacologia , Linfócitos T/imunologia , Timosina/análogos & derivados , Idoso , Células Cultivadas , Citotoxicidade Imunológica/efeitos dos fármacos , Feminino , Humanos , Imunoterapia Adotiva , Masculino , Glicoproteínas de Membrana/biossíntese , Pessoa de Meia-Idade , Neoplasias/imunologia , Perforina , Proteínas Citotóxicas Formadoras de Poros , Receptores de Interleucina-2/análise , Timosina/farmacologia
5.
Immunopharmacol Immunotoxicol ; 20(3): 355-72, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9736441

RESUMO

This report demonstrates that in vitro activation of human cells with the beta-galactoside-specific lectin from mistletoe (ML-I) or interleukin-2 (IL-2) results in different patterns of activation and function of cytotoxic cells. It is now well established that natural killer (NK) and lymphokine-activated killer (LAK) cytotoxicity is mainly mediated by resting (NK) and IL-2-activated (LAK) CD56-positive (+) cells respectively. Culture of peripheral blood lymphocytes (PBL) for 3 days with ML-I led to expansion and activation of T cells which demonstrated NK- and LAK-like cytotoxicity. T lymphocyte subset analysis revealed that in total PBL, ML-I preferentially stimulated and expanded CD8+ T cells which mediated the cytotoxic effect. Incubation of highly purified CD8+ T cells alone with ML-I did not lead to induction of cytotoxicity, which required the presence of both CD4+ and CD14+ (monocytes) cells, suggesting that ML-I does not exert a direct effect on CD8+ T cells. Activation of PBL with both ML-I and IL-2 resulted in simultaneous induction of T and CD56+ cell-mediated NK and LAK cytotoxicity. These data suggest that treatment with ML-I and IL-2 might provide an approach to induce maximum cytotoxicity against tumors and to recruit both T and NK cells for tumor therapy.


Assuntos
Citotoxicidade Imunológica/efeitos dos fármacos , Interleucina-2/farmacologia , Células Matadoras Ativadas por Linfocina/imunologia , Preparações de Plantas , Proteínas de Plantas , Toxinas Biológicas/farmacologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Sinergismo Farmacológico , Humanos , Proteínas Inativadoras de Ribossomos Tipo 2
6.
Anticancer Res ; 18(3A): 1501-8, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9673361

RESUMO

The prognosis of breast cancer is of major clinical importance and several histopathological, biochemical and immunological variables have been reported to be useful prognostic factors. In the present study, we investigated the clinical significance of the levels of alpha-thymosins in relation to established prognostic factors, both in breast cancer and non-malignant breast lesions, alpha-thymosin levels were measured in breast tissue extracts by specific radioimmunoassays (RIAs) developed for human prothymosin alpha (ProT alpha) and parathymosin alpha (ParaT alpha) and were found to be significantly higher (up to 17.2-fold) in malignant but not in benign breast lesions, as compared to the values of the neighbouring tissues. When alpha-thymosin levels of the tumor samples were correlated with various known prognostic parameters a statistically significant correlation (p < 0.05) was observed between the levels of ProT alpha in malignant tissues to the grade of cancer and the lymph node status of the patient. An association between ProT alpha levels with increase in risk of death from breast cancer was also noticed. These results suggest that the expression of alpha-thymosins in human breast cancer a) depends on the proliferation status of the tumor, b) associates with established prognostic factors describing the metastatic potential of the tumor and c) is related to the overall survival of the patient. The fact that such relationships hold only for cancer tissues encourages the future use of alpha-thymosins as potent prognostic factors in breast cancer.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Timosina/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Especificidade de Anticorpos , Neoplasias da Mama/mortalidade , Reações Cruzadas , Feminino , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prognóstico , Radioimunoensaio , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Taxa de Sobrevida , Timosina/análogos & derivados
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