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1.
Ann Oncol ; 23(11): 2953-2959, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22767583

RESUMO

BACKGROUND: To evaluate long-term toxicity and efficacy of a combined modality strategy including extended-field radiotherapy (EF-RT) or involved-field radiotherapy (IF-RT), the German Hodgkin Study Group carried out a follow-up analysis in patients with early unfavorable Hodgkin's lymphoma (HL). PATIENTS AND METHODS: One thousand two hundred and four patients were randomized to four cycles of chemotherapy followed by either 30 Gy EF- or 30 Gy IF-RT (HD8 trial); 532 patients in each treatment arm were eligible. RESULTS: At 10 years, no arm differences were revealed with respect to freedom from treatment failure (FFTF) (79.8% versus 79.7%), progression-free survival (79.8% versus 80.0%), and overall survival (86.4% versus 87.3%). Non-inferiority of IF-RT was demonstrated for the primary end point FFTF (95% confidence interval for hazard ratio 0.72-1.25). Elderly patients had a poorer outcome when treated with EF-RT. So far, 15.0% of patients in arm A and 12.2% in arm B died, mostly due to secondary malignancies (5.3% versus 3.4%) or HL (3.2% versus 3.4%). After EF-RT, there were more secondary malignancies overall (58 versus 45), especially acute myeloid leukemias (11 versus 4). CONCLUSION: Radiotherapy intensity reduction to IF-RT does not result in poorer long-term outcome but is associated with less acute toxicity and might be associated with less secondary malignancies.


Assuntos
Doença de Hodgkin/terapia , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Terapia Combinada/efeitos adversos , Ciclofosfamida/efeitos adversos , Ciclofosfamida/uso terapêutico , Intervalo Livre de Doença , Feminino , Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/mortalidade , Doença de Hodgkin/radioterapia , Humanos , Masculino , Pessoa de Meia-Idade , Prednisona/efeitos adversos , Prednisona/uso terapêutico , Procarbazina/efeitos adversos , Procarbazina/uso terapêutico , Radioterapia/efeitos adversos , Vincristina/efeitos adversos , Vincristina/uso terapêutico , Adulto Jovem
2.
Ann Oncol ; 18(2): 357-63, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17071932

RESUMO

BACKGROUND: The optimal treatment of elderly patients with Hodgkin's lymphoma (HL) is still a matter of debate. Since many of these patients receive combined modality treatment, we evaluated the impact of different radiation field sizes, that is extended-field (EF) or involved-field (IF) technique when given after four cycles of chemotherapy. PATIENTS AND METHODS: In the multicenter HD8 study of the German Hodgkin Study Group, 1204 patients with early-stage unfavorable HL were randomized to receive four cycles of chemotherapy followed by either radiotherapy (RT) of 30 Gy EF + 10 Gy to bulky disease (arm A) or 30 Gy IF + 10 Gy to bulky disease (arm B). A total of 1064 patients were assessable for the analysis. Of these, 89 patients (8.4%) were 60 years or older. RESULTS: Elderly patients had a poorer risk profile. Acute toxicity from RT was more pronounced in elderly patients receiving EF-RT compared with IF-RT [World Health Organization (WHO) grade 3/4: 26.5% versus 8.6%)]. Freedom from treatment failure (FFTF, 64% versus 87%) and overall survival (OS, 70% versus 94%) after 5 years was lower in elderly patients compared with younger patients. Importantly, elderly patients had poorer outcome when treated with EF-RT compared with IF-RT in terms of FFTF (58% versus 70%; P = 0.034) and OS (59% versus 81%; P = 0.008). CONCLUSION: Elderly patients with early-stage unfavorable HL generally have a poorer risk profile and outcome when compared with younger patients. Treatment with EF-RT instead of IF-RT after chemotherapy has a negative impact on survival of elderly patients and should be avoided.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/radioterapia , Lesões por Radiação/etiologia , Adolescente , Adulto , Idoso , Bleomicina/uso terapêutico , Terapia Combinada , Ciclofosfamida/uso terapêutico , Dacarbazina/uso terapêutico , Progressão da Doença , Doxorrubicina/uso terapêutico , Feminino , Alemanha , Doença de Hodgkin/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prednisona/uso terapêutico , Procarbazina/uso terapêutico , Prognóstico , Taxa de Sobrevida , Resultado do Tratamento , Vimblastina/uso terapêutico , Vincristina/uso terapêutico
3.
Z Gastroenterol ; 41(9): 913-6, 2003 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-13130328

RESUMO

We report the case of a 44-year-old woman who was admitted to our hospital because of a newly developed painless jaundice. Though she felt quite well sonographic and radiographic evaluation showed a tumor of the liver. An extensive diagnostic workup was performed but it was not until laparotomy that a malignant tumor could definitely be ruled out and the presumptive diagnosis of an echinococcosis was proven. A partial resection of the liver was performed.


Assuntos
Equinococose Hepática/diagnóstico , Adulto , Carcinoma Hepatocelular/diagnóstico , Diagnóstico Diferencial , Equinococose Hepática/diagnóstico por imagem , Equinococose Hepática/cirurgia , Feminino , Humanos , Laparotomia , Neoplasias Hepáticas/diagnóstico , Tomografia Computadorizada por Raios X , Ultrassonografia
4.
Histopathology ; 39(6): 561-5, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11903572

RESUMO

AIM: We report a case of mantle cell lymphoma masquerading as a marginal zone cell lymphoma. METHODS AND RESULTS: In the initial manifestation in the palatine tonsils, the neoplastic cells were found to grow exclusively within the marginal zones of secondary follicles which showed a preserved mantle zone. The few immunostains performed showed a B-cell phenotype including an immunoglobulin light chain restriction. The extranodal manifestation, the growth pattern, and the immunophenotype led to the diagnosis of an extranodal marginal zone B-cell non-Hodgkin's lymphoma (NHL). The specimen from the relapse occurring 8 months later exhibited diffuse monomorphous cells co-expressing B-cell antigens and CD5, CD43 and cyclin D1, leading to the diagnosis of mantle cell lymphoma. Re-investigation of the initial biopsy revealed that the neoplastic cells within the marginal zones had a mantle cell lymphoma immunophenotype expressing cyclin D1, the immunoglobulin heavy chains IgD and IgM and partly CD5. Both lesions harboured identical clonal immunoglobulin gene rearrangements proving that they represented different manifestations of the same lymphoma. CONCLUSION: This case emphasizes the importance of broad immunohistological investigation of B-cell NHLs involving the marginal zone.


Assuntos
Antígenos CD , Linfoma de Células B/patologia , Linfoma de Célula do Manto/patologia , Antígenos CD5/análise , Ciclina D1/análise , Diagnóstico Diferencial , Humanos , Cadeias Pesadas de Imunoglobulinas/análise , Imuno-Histoquímica , Leucossialina , Linfoma de Células B/metabolismo , Linfoma de Célula do Manto/metabolismo , Masculino , Pessoa de Meia-Idade , Sialoglicoproteínas/análise
6.
Bone Marrow Transplant ; 23(8): 771-7, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10231138

RESUMO

We studied the immunomodulating effect of withdrawal of immunosuppression with cyclosporin A (CsA) in 42 patients with leukemic relapse of chronic myelogenous leukemia (CML) (n = 24), acute myeloid leukemia (AML) (n = 13) and acute lymphoblastic leukemia (ALL) (n = 5) after allogeneic unmanipulated bone marrow (BMT) or peripheral blood stem cell transplantation (PBSCT). Response to CsA withdrawal was monitored molecularly by the polymerase chain reaction for elimination of CML cells containing the bcr-abl messenger RNA (mRNA) transcript (n = 24), or mll-af4 mRNA transcript characteristic of leukemic cells with a 11q23 chromosomal abnormality (n = 1). Rapid tapering of CsA resulted in subsequent achievement of cytogenetic remission in 11 of 14 CML patients (79%) who relapsed in early disease phase (n = 9 cytogenetic relapse, n = 2 hematological relapse) after a median of 57 days. Three of 13 AML patients and one of five ALL patients achieved complete remission. CsA withdrawal was accompanied by the development of acute graft-versus-host disease (GVHD) grade II in most of the 24 patients with CML. Two patients who achieved remission of AML or ALL died from severe GVHD grade III-IV. We calculated a probability of 84% for achieving and remaining in remission with early relapse of CML 4 years after relapse post BMT, whereas patients with AML have only a probability of about 10% of achieving and remaining in remission after 3 years. Patients with advanced CML and ALL had no chance of achieving and remaining in remission in the same time period.


Assuntos
Transplante de Medula Óssea , Ciclosporina/farmacologia , Efeito Enxerto vs Tumor/efeitos dos fármacos , Imunossupressores/farmacologia , Leucemia/terapia , Adolescente , Adulto , Feminino , Doença Enxerto-Hospedeiro/etiologia , Humanos , Imunoterapia , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Transplante Homólogo
7.
Z Gastroenterol ; 37(2): 159-63, 1999 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-10190249

RESUMO

Sarcoidosis is a chronic multisystem disorder of unknown cause characterized by the presence of noncaseating epitheloid granulomas and derangement of the normal skin architecture. Though an array of organs may be affected by the disease the most common site of affection is the lung. An extrathoratic manifestation is rare. We describe a 66-year-old patient who was admitted to our hospital because of weight loss and hepatomegaly. A thorough examination revealed the diagnosis of a granulomatous hepatitis characterized by a markedly elevated alkaline phosphatase concentration of 1,490 U/I. A drug-induced hepatitis could be excluded and no evidence was found for the existence of a bacterial or viral infection or an autoimmune disorder. An ERCP revealed a normal common bile duct and normally branching small intrahepatic ducts. The patient was discharged with the diagnosis of a biliary cirrhosis. Half a year later the patient was readmitted to the hospital because of severe intestinal bleeding due to pancytopenia. A bone marrow biopsy showed infiltration of the marrow by granulomas. A histiocytosis X could be ruled out. The diagnosis of an extrathoracic sarcoidosis was assumed and a therapy with prednisone was started. Within six weeks the blood count normalized. After 18 months the serum alkaline phospatase concentration also normalized and no granulomas were found in the bone marrow. The case demonstrates that pancytopenia in sarcoidosis is not due to bone marrow failure.


Assuntos
Hepatite/patologia , Osteomielite/patologia , Sarcoidose/patologia , Idoso , Biópsia , Medula Óssea/patologia , Diagnóstico Diferencial , Humanos , Fígado/patologia , Masculino , Pancitopenia/patologia
8.
Dtsch Med Wochenschr ; 124(49): 1482-4, 1999 Dec 10.
Artigo em Alemão | MEDLINE | ID: mdl-10629666

RESUMO

BACKGROUND AND OBJECTIVE: Endoscope-guided fine-needle biopsy of mediastinal space-occupying lesions is a recently introduced method of low invasiveness. This is a report of the authors' experience. PATIENTS AND METHODS: Between Nov. 1996 and April 1999 endoscope-guided mediastinal biopsies (Pentax FG 32 UA) were performed in 31 patients (eight women, 23 men; aged 27-80 years). The space-occupying lesion had to be less than 1 cm from the oesophagus and not more easily approachable in other ways. RESULTS: The method was successful in 23 of the 31 patients (74%). In ten of the 31 patients (32%) a malignant lesion was histologically proven. In six patients (19%) sarcoidosis was revealed. Of the eight patients with inadequate biopsy material a malignancy was ultimately diagnosed in three, sarcoidosis in one (in three by mediastinoscopy, in one by laparoscopy). Thus the sensitivity of diagnosing a malignancy was 77%, with a specificity of 100%. Follow-up examinations in the remaining four patients excluded a malignancy. CONCLUSION: Endoscope-guided fine-needle biopsy of mediastinal space-occupying lesions is a technically simple method causing little stress to the patient that can frequently elucidate the lesion's benignity or malignancy. Invasive procedures, such as mediastinoscopy, may thus be avoided in some patients.


Assuntos
Doenças do Mediastino/patologia , Mediastino/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha/métodos , Diagnóstico Diferencial , Endossonografia/métodos , Feminino , Seguimentos , Humanos , Masculino , Doenças do Mediastino/diagnóstico por imagem , Neoplasias do Mediastino/diagnóstico por imagem , Neoplasias do Mediastino/patologia , Mediastino/diagnóstico por imagem , Pessoa de Meia-Idade , Sarcoidose/diagnóstico por imagem , Sarcoidose/patologia , Sensibilidade e Especificidade
9.
Leuk Lymphoma ; 29(1-2): 103-18, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9638980

RESUMO

In a prospective multicenter study 68 out of 158 patients with HIV infection and malignant lymphoma were assigned to a risk-adapted induction therapy using the following algorithm: High-risk patients fulfilled 2 of 3 criteria: T4 lymphocytes <50/microL; WHO activity index 3 or 4; pre-existing AIDS-defining opportunistic infection. Normal-risk patients received 4 to 6 cycles of CHOP chemotherapy; those that achieved complete remission (CR) received zidovudine (500 mg/d) and interferon-alpha maintenance therapy (5 million units three times a week) for one year. High-risk patients received low-dose CHOP or vincristine/prednisone chemotherapy. Supportive care was performed with pentamidine inhalation and G-CSF. Intrathecal (it) methotrexate was given for CNS prophylaxis. The median survival was 634 days for 38 patients of the normal-risk group and 129 days for 30 patients of the high-risk group. 18 high-risk patients treated with low-dose CHOP had better survival (156 days) than 12 patients treated with vincristine/prednisone (72 days p=0.044). 68% of the patients in the normal-risk group achieved complete remission. 5 out of 18 high-risk patients treated with low-dose CHOP achieved complete remission. Three normal-risk patients developed fatal opportunistic infections during chemotherapy. Immune parameters deteriorated after CHOP induction and partially recovered with maintenance treatment. We conclude that the normal-risk patients survived longer than reported in most published studies. Toxicity was low. Low-dose CHOP seems to be superior to vincristine/prednisone therapy in high-risk patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma Relacionado a AIDS/tratamento farmacológico , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Feminino , Humanos , Interferon alfa-2 , Interferon-alfa/administração & dosagem , Linfoma Relacionado a AIDS/mortalidade , Masculino , Projetos Piloto , Prednisona/administração & dosagem , Estudos Prospectivos , Proteínas Recombinantes , Fatores de Risco , Taxa de Sobrevida , Resultado do Tratamento , Vincristina/administração & dosagem , Zidovudina/administração & dosagem
10.
Mod Pathol ; 11(5): 485-90, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9619603

RESUMO

We evaluated the clonal relationship between a case of nodular sclerosis Hodgkin's disease (NSHD) and a small noncleaved cell (SNC) lymphoma that subsequently developed. Single Hodgkin and Reed-Sternberg (H-RS) cells were isolated from immunostained sections of the NSHD by micromanipulation, and the immunoglobulin heavy chain gene (IgH) complementarity determining region (CDR) III of the cells was amplified by the polymerase chain reaction (PCR). A clonal population of H-RS cells was found in the NSHD tumor. The nucleotide sequence of the clonal H-RS cells was compared with the clonal IgH CDRIII sequence from the SNC lymphoma. The two sequences were found to be unrelated. In addition, clone-specific primers and probes were designed from the two clonal IgH CDRIII sequences and used to investigate the presence of the respective clonal population in the NSHD tumor. The latter studies confirmed the presence of a major clonal H-RS cell population, as detected by the single cell assay, but cells corresponding to the SNC clone were not demonstrable by this highly sensitive technique. These findings suggest that the SNC arising in this case represents the development of the second neoplasm clonally unrelated to the preceding NSHD. They also support the recent findings that the H-RS cells in classical HD consist of a clonal population of B cells.


Assuntos
Doença de Hodgkin/patologia , Linfonodos/patologia , Linfoma de Células B/patologia , Células de Reed-Sternberg/patologia , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linhagem Celular , Terapia Combinada , Ciclofosfamida/uso terapêutico , Doença de Hodgkin/radioterapia , Humanos , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/radioterapia , Masculino , Segunda Neoplasia Primária/tratamento farmacológico , Segunda Neoplasia Primária/patologia , Segunda Neoplasia Primária/radioterapia , Reação em Cadeia da Polimerase , Prednisona/uso terapêutico , Procarbazina/uso terapêutico , Esclerose , Vincristina/uso terapêutico
11.
Clin Nucl Med ; 21(8): 619-25, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8853914

RESUMO

A series of plain radiographs, bone scans, bone marrow scans, and MRIs is reported in a patient with Gaucher disease type I, in whom two episodes of acute bone crisis developed during a 6-year period of follow-up. Acute bone crisis and global indolent bone marrow displacement could both be assessed by bone marrow scintigraphy, whereas MRI could better clarify the corti-comedullary alteration after bone infarction. Thus, MRI and bone marrow scintigraphy could be used as complementary imaging methods in the management of patients with Gaucher disease.


Assuntos
Diagnóstico por Imagem , Doença de Gaucher/diagnóstico , Doença Aguda , Adulto , Biópsia , Doenças Ósseas/diagnóstico , Doenças Ósseas/diagnóstico por imagem , Medula Óssea/irrigação sanguínea , Medula Óssea/diagnóstico por imagem , Medula Óssea/patologia , Osso e Ossos/irrigação sanguínea , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/patologia , Seguimentos , Doença de Gaucher/classificação , Doença de Gaucher/diagnóstico por imagem , Doença de Gaucher/patologia , Humanos , Infarto/diagnóstico , Imageamento por Ressonância Magnética , Masculino , Dor/diagnóstico , Cintilografia , Compostos Radiofarmacêuticos , Medronato de Tecnécio Tc 99m , Coloide de Enxofre Marcado com Tecnécio Tc 99m , Tomografia Computadorizada por Raios X
12.
Scand J Immunol ; 44(2): 150-6, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8711428

RESUMO

The authors analysed the effect of protein kinase A (PKA) activation on the protein synthesis and secretion in the T-helper 2 cell line D10.G4.1 (D10) using an assay that allows the detection of almost all secreted proteins of a cell. IL-4 and IL-10 were quantified. Three groups of secretory products could be defined. The T-cell receptor (TCR)-induced production of the first group (A) of proteins including IL-4 was enhanced by low concentrations of PKA activators. At higher concentrations the enhancement was less marked. The synthesis and secretion of a second group (B) of proteins including IL-10 remained unaffected. The production of a third group (C) of proteins was inhibited in a concentration-dependent manner. Biochemical analysis revealed a block of phospholipase C gamma (PLC gamma) activity by PKA activators. When D10 cells were stimulated by a phorbol ester plus calcium ionophore the production of group A proteins was enhanced almost fourfold, whereas production of group B proteins was unaffected by PKA activation. This effect was observed at all concentrations of various PKA activators tested. The secretion of group C proteins was no longer inhibited. The same results were obtained when analysing IL-4 and IL-10 m-RNA by Northern blotting. The data demonstrate a lymphokine specific mode of action on a single cell basis. Furthermore, it suggests that the inhibitory action of PKA in D10 cells is due partly to blocking of PLC gamma activity.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/fisiologia , Interleucina-10/biossíntese , Interleucina-4/biossíntese , 1-Metil-3-Isobutilxantina/farmacologia , Animais , Linhagem Celular , Ativação Enzimática , Humanos , Interleucina-10/genética , Interleucina-10/metabolismo , Interleucina-4/genética , Interleucina-4/metabolismo , Camundongos , Camundongos Endogâmicos C3H , RNA Mensageiro/análise , Coelhos , Ratos , Receptores de Antígenos de Linfócitos T/fisiologia , Acetato de Tetradecanoilforbol/farmacologia , Células Th2/metabolismo , Fosfolipases Tipo C/antagonistas & inibidores
13.
J Immunol Methods ; 161(1): 41-57, 1993 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-8486928

RESUMO

Using metabolic radiolabelling of proteins, which are newly synthesized during TCR-triggered T cell activation we were able to visualize distinct patterns of secreted polypeptides (with molecular weights ranging from 6 to 44 kDa) in supernatants of different T helper-1, T helper-2 and cytotoxic T cell clones. Most of these detected proteins are secreted in response to TCR-crosslinking (or to combined action of PMA and A231287), in an extracellular Ca(2+)-dependent manner and their appearance in supernatants was completely blocked by the addition of RNA synthesis or protein synthesis inhibitors or EGTA. Cyclosporin A (CsA) blocks secretion of several detected polypeptides, but does not affect TCR-triggered synthesis and secretion of others reflecting the existence of TCR-triggered, CsA-insensitive protein synthesis and secretion pathway. The insensitivity of secretion of several easily detectable polypeptides to inhibition by CsA offers a promising approach to further define the CsA-resistant and calcineurin-independent molecular pathways of TCR-triggered T cell activation. Several lymphokines (e.g., interferon-gamma, tumor necrosis factor, interleukin-4 and interleukin-10) are identified among the visualized set of secreted polypeptides. Since other, yet unidentified, secreted polypeptides in the same set of secreted proteins share important properties with known lymphokines it seems promising to use described approach in search for new lymphokines.


Assuntos
Ativação Linfocitária , Linfocinas/análise , Receptores de Antígenos de Linfócitos T alfa-beta/fisiologia , Linfócitos T Citotóxicos/metabolismo , Linfócitos T Auxiliares-Indutores/metabolismo , Animais , Células Clonais , Ciclosporina/farmacologia , Técnicas In Vitro , Interferon gama/metabolismo , Interleucina-10/metabolismo , Interleucina-4/metabolismo , Linfocinas/metabolismo , Camundongos , Agregação de Receptores , Fator de Necrose Tumoral alfa/metabolismo
14.
Biochem J ; 285 ( Pt 1): 137-41, 1992 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-1637292

RESUMO

We have tested whether phytohaemagglutinin (PHA)-stimulated generation of inositol phosphates (IP) and increases in intracellular Ca2+ can be dissociated in human mononuclear leucocytes. Lowering the incubation temperature from 37 degrees to 25 degrees C decreased PHA-stimulated IP generation by more than 80%, but only marginally affected PHA-stimulated Ca2+ increases. In the absence of extracellular Ca2+, PHA did not stimulate IP generation or Ca2+ increases, although PHA binding to its acceptor sites was not impaired. Increasing extracellular Ca2+ up to 0.15 mM enhanced PHA-stimulated PHA generation but this increase was attenuated by further increasing extracellular Ca2+ to 2.6 mM. Increasing extracellular Ca2+ to 0.3 mM also enhanced PHA-stimulated Ca2+ increases, and further increasing extracellular Ca2+ did not affect it. Co-treatment with 100 microM-prostaglandin E2 completely abolished PHA-stimulated IP generation, but inhibited Ca2+ increases by only 20-30%. These results could be explained by IP-generation-independent Ca2+ increases or by non-linear coupling of IP generation to Ca2+ increases. Since the PHA concentrations required to increase Ca2+ were greater than those required for IP generation, the latter hypothesis can be excluded. Furthermore, the Ca2+ ionophore ionomycin increased intracellular Ca2+ and weakly stimulated IP generation, but with very similar concentration-response relationships. Our data suggest that PHA-stimulated IP generation and Ca2+ increases in human mononuclear leucocytes mainly occur independently of one another rather than sequentially.


Assuntos
Cálcio/metabolismo , Fosfatos de Inositol/biossíntese , Leucócitos Mononucleares/metabolismo , Fito-Hemaglutininas , Cátions Bivalentes , Dinoprostona/farmacologia , Feminino , Humanos , Técnicas In Vitro , Ionomicina/farmacologia , Leucócitos Mononucleares/efeitos dos fármacos , Masculino , Espectrometria de Fluorescência , Temperatura
15.
J Immunol ; 148(5): 1338-46, 1992 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-1311347

RESUMO

To characterize the requirements for the induction of an anergic state in immunocompetent cells we examined the effect of an increase in intracellular calcium concentration on the subsequent responsiveness of cytolytic T cells to antigenic stimulation in vitro. Pretreatment of a murine cytolytic T cell clone with the calcium-ionophore A23187 resulted in the induction of an anergic state characterized by a decrease in cytolytic activity and granule exocytosis upon Ag-specific stimulation. Furthermore, IFN-gamma synthesis declined whereas de novo synthesis of a yet unidentified protein with a molecular mass of 33 kDa as well as proliferative response of cells in response to exogenous IL-2 were unaffected. This state of partial unresponsiveness 1) could be prevented by concomitant pretreatment of cells with cyclosporin A or protein synthesis inhibitors and 2) was reversible within 48 h. Biochemical analysis of TCR-induced intracellular activation revealed a block in signal transduction before the activation of protein kinase C because cellular unresponsiveness could be bypassed by the phorbol ester PMA plus the calcium-ionophore A23187. However, phosphatidylinositol turnover was markedly inhibited in unresponsive cells that also did not show a calcium influx on stimulation with concanavalin A. We conclude that a rise in intracellular calcium in cytolytic T cells might not only be necessary for cellular activation but may also trigger the induction of a partial unresponsiveness to antigenic stimulation due to an inhibition in the early phase of signal transduction.


Assuntos
Calcimicina/farmacologia , Linfócitos T Citotóxicos/efeitos dos fármacos , Cálcio/metabolismo , Células Clonais , Cicloeximida/farmacologia , Ciclosporina/farmacologia , Exocitose , Humanos , Interleucina-2/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Fosfatidilinositóis/metabolismo , Proteínas/análise , Receptores de Antígenos de Linfócitos T/análise , Linfócitos T Citotóxicos/fisiologia
17.
J Immunol ; 142(11): 3796-802, 1989 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-2541201

RESUMO

We have examined the effects of cyclosporine A (CsA) on a number of CTL effector functions. CsA partially inhibited the CTL-mediated lysis of Ag-bearing target cells. Both target cell- and anti-TCR mAb-induced granule exocytosis were markedly inhibited by CsA. In addition, marked inhibition of PMA and calcium ionophore (A23187) induced granule exocytosis was produced by CsA suggesting that the inhibitory effects of CsA on granule exocytosis involve biochemical events after protein kinase C activation and increases in intracellular free Ca2+. CsA had no inhibitory effects on TCR-mediated phosphatidylinositol metabolism. The inhibitory effects of CsA were not mediated by the cAMP-dependent protein kinase inhibitory pathway and no effect of CsA on the Ca2+-induced binding of calmodulin to calmodulin-binding proteins could be demonstrated. CsA was also a potent inhibitor of IgE receptor-mediated exocytosis in rat basophil leukemia cells. CsA had no effect on receptor-mediated phosphatidylinositol hydrolysis; 400 ng/ml CsA resulted in a 90% inhibition of serotonin release but had no effect on phosphatidylinositol hydrolysis. These results indicate that CsA may inhibit some common event in Ca2+-dependent secretory cells. Taken together, these results suggest that CsA does not inhibit signal transduction but rather interferes with the biochemical events in the later stages of Ca2+-dependent reactions that follow the binding of calmodulin to cytoskeletal or cytoplasmic calmodulin binding proteins.


Assuntos
Ciclosporinas/farmacologia , Citotoxicidade Imunológica/efeitos dos fármacos , Linfócitos T Citotóxicos/efeitos dos fármacos , Animais , Calcimicina , Proteínas de Ligação a Calmodulina/metabolismo , Grânulos Citoplasmáticos/efeitos dos fármacos , Grânulos Citoplasmáticos/fisiologia , Exocitose/efeitos dos fármacos , Mastócitos/efeitos dos fármacos , Mastócitos/fisiologia , Camundongos , Fosfatidilinositol 4,5-Difosfato , Fosfatidilinositóis/metabolismo , Receptores de Antígenos de Linfócitos T/efeitos dos fármacos , Receptores de Antígenos de Linfócitos T/fisiologia , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo , Acetato de Tetradecanoilforbol
18.
J Immunol ; 140(4): 1101-6, 1988 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-3257770

RESUMO

B cell stimulatory factor 1 (BSF-1) (IL-4) was shown to synergize with phorbol esters or with monoclonal anti-TCR antibody in stimulation of the development of CTL from small resting murine T cells. IL-2 also synergized with PMA in such differentiation but was less effective than BSF-1. The combination of these two lymphokines with PMA had the most potent effect on the development of CTL. BSF-1 plus PMA stimulated a significant increase in the intracellular content of N-benzyloxycarbonyl-L-lysine thiobenzylester esterase, a granule-associated biochemical marker, whereas IL-2 plus PMA was only marginally effective. Depletion of L3T4+ cells did not result in the abrogation of these effects. Lyt-2+ T cells that were incubated for 72 h with BSF-1 plus PMA accumulated N-benzyloxycarbonyl-L-lysine thiobenzylester esterase and secreted this intragranular marker after interaction with immobilized anti-T cell receptor mAb. These BSF-1/PMA-stimulated Lyt-2+, L3T4- T cells were also able to kill FcR positive target cells in a retargeting assay with a mAb to murine T3 Ag, providing evidence that BSF-1 plus PMA acted directly on precursors of cytotoxic T cells.


Assuntos
Interleucinas/farmacologia , Linfócitos T Citotóxicos/citologia , Linfócitos T/efeitos dos fármacos , Animais , Anticorpos Monoclonais/imunologia , Antígenos Ly/análise , Diferenciação Celular/efeitos dos fármacos , Citotoxicidade Imunológica/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Granzimas , Interleucina-2/farmacologia , Interleucina-4 , Camundongos , Camundongos Endogâmicos BALB C , Receptores de Antígenos de Linfócitos T/imunologia , Serina Endopeptidases/análise , Serina Endopeptidases/metabolismo , Linfócitos T/citologia , Linfócitos T/metabolismo , Acetato de Tetradecanoilforbol/farmacologia
19.
Cell Differ ; 22(3): 233-44, 1988 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3258549

RESUMO

Composition of surface proteins and their interactions with cytoskeleton or membrane matrix were compared in tumor B-cell lines of different stages of B-lymphocyte maturation. All studied B-cell lines were found to share a similar set of cell surface proteins, which are tightly associated with the cytoskeleton. The increase in amount of detergent-unextractable cell surface proteins with B-cell maturation suggested that differentiation of B lymphocytes was accompanied by development of specific interactions between surface proteins and elements of the cytoskeleton or membrane matrix. Using a recently developed procedure for lymphocyte plasma membrane fractionation we demonstrate changes in distribution of cell surface proteins in membrane matrix-rich and membrane matrix-poor plasma membrane fractions during B-lymphocyte maturation. Thus, cell surface proteins of the mature B-cell line MOPC-315 were predominantly found in the plasma membrane vesicles of a high buoyant density. These vesicles mostly contained plasma membrane proteins tightly associated with elements of the membrane matrix. In immature B cells (line 70Z3) virtually all surface proteins were detected in both low and high buoyant density membrane vesicles. The tendency to increased associations between surface proteins and cytoskeleton/membrane matrix with maturation of B cells could not be explained by increased amounts of filamentous actin, since no correlation was found between the amount of globular or filamentous actin and the degree of surface protein-cytoskeleton (membrane matrix) interactions.


Assuntos
Linfócitos B/ultraestrutura , Proteínas de Membrana/fisiologia , Actinas/fisiologia , Animais , Diferenciação Celular , Linhagem Celular , Membrana Celular/ultraestrutura , Fracionamento Químico , Citoesqueleto/fisiologia
20.
J Biol Chem ; 263(5): 2330-6, 1988 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-2448308

RESUMO

The mechanism of the cAMP involvement in regulation of cellular functions was studied here using a novel functional assay (antigen receptor-triggered exocytosis of granules) of cloned cytotoxic T lymphocytes (CTL). We suggest that cAMP-dependent protein kinase, protein kinase A, counteracts the protein kinase C and Ca2+-mediated stimulatory T-cell antigen receptor (TcR)-triggered biochemical pathway. This suggestion is supported by experimental results which satisfy criteria for protein kinase A involvement in cellular functions. Pretreatment of CTL with cholera toxin induces cAMP accumulation in CTL, partially inhibits TcR-triggered "lethal hit" delivery to the target cell, and almost completely blocks TcR-triggered exocytosis of granules from CTL. Other agents that raise the intracellular level of cAMP, including forskolin and isobutylmethylxanthine (IBMX) also inhibit TcR-triggered CTL activation. Involvement of cAMP-dependent protein kinase in an inhibitory pathway is suggested by the synergistic effects of cyclic nucleotide analogs 8-bromo-cAMP and N6-benzoyl-cAMP in inhibition of TcR-triggered exocytosis. Forskolin and IBMX inhibited TcR-triggered phosphoinositide turnover in CTL, suggesting that cAMP affected very early events in signal transduction that follow TcR cross-linking by a ligand. The ability of IBMX to inhibit CTL activation when the TcR cross-linking step was by-passed by the combination of phorbol myristate acetate and ionophore A23187 suggests that the locus of inhibitory effect of cAMP is at both the early and late stages of the TcR-triggered transmembrane signaling pathway.


Assuntos
Ativação Linfocitária , Proteínas Quinases/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T Citotóxicos/metabolismo , 1-Metil-3-Isobutilxantina/farmacologia , Animais , Calcimicina/farmacologia , Toxina da Cólera/farmacologia , Colforsina/análogos & derivados , Colforsina/farmacologia , AMP Cíclico/metabolismo , Citotoxicidade Imunológica/efeitos dos fármacos , Exocitose , Acetato de Tetradecanoilforbol/farmacologia
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