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1.
Transfus Apher Sci ; 58(5): 641-644, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31519525

RESUMO

OBJECTIVE: The World Apheresis Association (WAA) register contains data from more than 89 000 apheresis procedures in more than 12,000 patients. The aim of this study was to evaluate functional health and quality of life (QoL) in patients during apheresis treatment. MATERIAL AND METHODS: Estimates of health condition (HC) were made in 40,445 and of QoL in 22112 apheresis procedures. This study focused on a 10-step graded evaluation of HC (scale from: 'bedridden, unable to eat' to a level of 'athletic competition') and self-assessment of QoL (scale from: worst ever '0' to best ever '10'). Data were compared in relation to various apheresis procedures and if the patient underwent the first or subsequent apheresis procedure. RESULTS: Of the patients treated with plasma exchange (PEX) with centrifugation technique (n = 15787) 10% were 'bedridden, unable to come out of bed' while for patients treated with plasma filtration technique (n = 1018) the percentage was 27%. During the first procedure these figures were 16% and 30%, respectively. Self-estimates of QoL were graded 'zero' or '1' in 1.6% of patients during the first apheresis procedure; At the first contact patients undergoing PEX graded like this in 4.3%. CONCLUSION: Many of the patients undergoing apheresis treatment have poor HC and QoL at the start of therapy. Of all therapeutic apheresis procedures patients undergoing PEX had the lowest score of QoL.


Assuntos
Troca Plasmática , Qualidade de Vida , Sistema de Registros , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
2.
Transfus Apher Sci ; 56(1): 71-74, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28162978

RESUMO

The WAA apheresis registry was established in 2003 and an increasing number of centers have since then included their experience and data of their procedures. The registry now contains data of more than 74,000 apheresis procedures in more than 10,000 patients. This report shows that the indications for apheresis procedures are changing towards more oncological diagnoses and stem cell collections from patients and donors and less therapeutic apheresis procedures. In centers that continue to register, the total extent of apheresis procedures and patients treated have expanded during the latest years.


Assuntos
Remoção de Componentes Sanguíneos/métodos , Humanos , Sistema de Registros
3.
Transfus Apher Sci ; 54(1): 2-15, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26776481

RESUMO

Apheresis with different procedures and devices are used for a variety of indications that may have different adverse events (AEs). The aim of this study was to clarify the extent and possible reasons of various side effects based on data from a multinational registry. The WAA-apheresis registry data focus on adverse events in a total of 50846 procedures in 7142 patients (42% women). AEs were graded as mild, moderate (need for medication), severe (interruption due to the AE) or death (due to AE). More AEs occurred during the first procedures versus subsequent (8.4 and 5.5%, respectively). AEs were mild in 2.4% (due to access 54%, device 7%, hypotension 15%, tingling 8%), moderate in 3% (tingling 58%, urticaria 15%, hypotension 10%, nausea 3%), and severe in 0.4% of procedures (syncope/hypotension 32%, urticaria 17%, chills/fever 8%, arrhythmia/asystole 4.5%, nausea/vomiting 4%). Hypotension was most common if albumin was used as the replacement fluid, and urticaria when plasma was used. Arrhythmia occurred to similar extents when using plasma or albumin as replacement. In 64% of procedures with bronchospasm, plasma was part of the replacement fluid used. Severe AEs are rare. Although most reactions are mild and moderate, several side effects may be critical for the patient. We present side effects in relation to the procedures and suggest that safety is increased by regular vital sign measurements, cardiac monitoring and by having emergency equipment nearby.


Assuntos
Remoção de Componentes Sanguíneos/efeitos adversos , Sistema de Registros , Sociedades Médicas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cálcio/administração & dosagem , Criança , Pré-Escolar , Coloides , Feminino , Humanos , Lactente , Recém-Nascido , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Troca Plasmática , Padrões de Referência , Fatores de Tempo , Doadores de Tecidos , Resultado do Tratamento , Adulto Jovem
4.
Vnitr Lek ; 59(4): 313-6, 2013 Apr.
Artigo em Cs | MEDLINE | ID: mdl-23711058

RESUMO

Acquired haemophilia A is a rare form of acquired coagulopathy caused by autoantibodies against coagulation factor VIII. It is characterized by major bleeding complications often life- threatening. An estimated incidence is about 1- 2 cases per million inhabitants per year. The authors report case history of acquired haemophilia in 85 year old woman. Bleeding complications were well controlled by bypassing agents. Inhibitor eradication was successful after the use of second line agent rituximab.


Assuntos
Hemofilia A/diagnóstico , Idoso de 80 Anos ou mais , Autoanticorpos/sangue , Fator VIII/imunologia , Feminino , Hemofilia A/tratamento farmacológico , Hemofilia A/imunologia , Humanos
5.
Prague Med Rep ; 113(4): 294-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23249661

RESUMO

Transfusion-related acute lung injury (TRALI) is a severe life-threatening complication of blood transfusion, characterized by acute lung injury developing within 2-6 h of transfusion. However, TRALI is difficult to diagnose, and the initial report or suspicion of TRALI depends on close collaboration between clinical departments and transfusion centres. A total of 17 adverse post-transfusion reactions were reported to the Blood Centre of the University Hospital Ostrava as suspected TRALI between 2005 and 2010. We report two cases of serious TRALI with different pathogenetic mechanisms.


Assuntos
Lesão Pulmonar Aguda/etiologia , Reação Transfusional , Lesão Pulmonar Aguda/diagnóstico , Feminino , Humanos , Pessoa de Meia-Idade
6.
Sci Rep ; 12(1): 18374, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36319704

RESUMO

An evidence-based treatment for a Multiple Sclerosis (MS) relapse is an intravenous administration of 3-5 g of Methylprednisolone. In case of insufficient effect or corticosteroids intolerance, the therapeutic plasma exchange (TPE) is indicated. To assess the clinical effect of TPE in treatment of relapse in patients with relapsing-remitting MS (RRMS), we enrolled 155 patients meeting the following criteria (study period: January 2011 to February 2021): (1) age > 18, (2) RRMS according to the McDonald´s 2017 criteria, (3) MS relapse and insufficient effect of corticosteroids/corticosteroids intolerance, (4) baseline EDSS < 8. Exclusion criteria: (1) progressive form of disease, (2) history of previous TPE. Following parameters were monitored: EDSS changes (before and after corticosteroid treatment, before and after TPE; EDSS after TPE was assessed at the next clinical follow-up at the MS Center), and improvement of EDSS according to the number of procedures and baseline severity of relapse. 115 females (74%) and 40 males (26%) were included. The median age was 41 years (IQR 33-47)-131 patients underwent the pulse corticosteroids treatment and TPE, while 24 patients underwent only TPE without any previous corticosteroid treatment. Median baseline EDSS was 4.5 (IQR 3.5-5.5), median EDSS after finishing steroids was 4.5 (IQR 4.0-5.5). EDSS prior to the TPE was 4.5 (IQR 4-6), EDSS after TPE was 4.5 (IQR 3.5-5.5). We observed a significant improvement in the EDSS after TPE (p < 0.001). Sex differences were seen in TPE effectiveness, with median improvement of EDSS in females being -0.5 (IQR 1-0) and in males being 0 (IQR -0.5 to 0), p = 0.048. There was no difference in EDSS improvement by age category: 18-30 years, 31-40 years, 41-50 years, > 50 (p = 0.94), nor by total TPE count (p = 0.91). In this retrospective study of patients with an aggressive relapse and insufficient effect of intravenous corticosteroid treatment, a significant effect of TPE on EDSS improvement was observed. There was no significant difference in TPE effectivity according to the number of procedures, age, nor severity of a relapse. In this cohort, TPE was more effective in females.


Assuntos
Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Humanos , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Adolescente , Adulto Jovem , Esclerose Múltipla/tratamento farmacológico , Troca Plasmática/métodos , Estudos Retrospectivos , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Recidiva , Corticosteroides/uso terapêutico
7.
Cas Lek Cesk ; 148(10): 493-6, 2009.
Artigo em Cs | MEDLINE | ID: mdl-20662412

RESUMO

BACKGROUND: Therapeutic plasma exchange is the treatment of choice for thrombotic thrombocytopenic purpura (TTP). METHODS AND RESULTS: Patients chronically treated with plasma exchange are frequently exposed to a large number of single plasma donors units, however successful clinical and laboratory improvement is generally achieved. Therapeutic plasma exchange significantly decreased mortality of this disease. Plasma treatment offers two possibilities--plasma infusion or plasma exchange and possibility of different plasma types. Cryoprecipitate-poor plasma was introduced as better form of FFP, however studies presented later did not confirm the therapeutic benefit. Quarantine FFP is widely used for patients with TTP in the Czech Republic; this type is tested frequently for negativity of human immunodeficiency virus, hepatitis B virus, hepatitis C virus and syphilis. Treatment with pathogen inactivated plasma (e.g., solvent detergent plasma, methylen-blue plasma, psoralen treated plasma or riboflavin treated plasma) is not frequently used in the Czech Republic. Authors present different plasma types and their experience with plasma treatment in seven patients with congenital form of TTP. CONCLUSIONS: In five patients therapeutic plasma exchange with quarantine fresh frozen plasma uas used. During each treatment 1.5 of plasma volume was exchanged. Two patients--teenagers were treated at the ex paediatric clinic with plasma infusion in regularly 2 weeks intervals.


Assuntos
Troca Plasmática , Púrpura Trombocitopênica Trombótica/terapia , Adolescente , Adulto , Feminino , Humanos , Masculino , Púrpura Trombocitopênica Trombótica/genética , Adulto Jovem
9.
Mol Cell Biol ; 21(19): 6369-86, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11533227

RESUMO

The avian homologue of the interferon regulatory factor 4 (IRF-4) and a novel splice variant lacking exon 6, IRF-4DeltaE6, were isolated and characterized. Chicken IRF-4 is expressed in lymphoid organs, less in small intestine, and lungs. IRF-4DeltaE6 mRNA, though less abundant than full-length IRF-4, was detected in lymphoid tissues, with the highest levels observed in thymic cells. IRF-4 is highly expressed in v-Rel-transformed lymphocytes, and the expression of IRF-4 is increased in v-Rel- and c-Rel-transformed fibroblasts relative to control cells. The expression of IRF-4 from retrovirus vectors morphologically transformed primary fibroblasts, increased their saturation density, proliferation, and life span, and promoted their growth in soft agar. IRF-4 and v-Rel cooperated synergistically to transform fibroblasts. The expression of IRF-4 antisense RNA eliminated formation of soft agar colonies by v-Rel and reduced the proliferation of v-Rel-transformed cells. v-Rel-transformed fibroblasts produced interferon 1 (IFN1), which inhibits fibroblast proliferation. Infection of fibroblasts with retroviruses expressing v-Rel resulted in an increase in the mRNA levels of IFN1, the IFN receptor, STAT1, JAK1, and 2',5'-oligo(A) synthetase. The exogenous expression of IRF-4 in v-Rel-transformed fibroblasts decreased the production of IFN1 and suppressed the expression of several genes in the IFN transduction pathway. These results suggest that induction of IRF-4 expression by v-Rel likely facilitates transformation of fibroblasts by decreasing the induction of this antiproliferative pathway.


Assuntos
Transformação Celular Viral , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/fisiologia , Fibroblastos/citologia , Proteínas Oncogênicas v-rel/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/fisiologia , Sequência de Aminoácidos , Animais , Proteínas Aviárias , Sequência de Bases , Divisão Celular , Linhagem Celular , Células Cultivadas , Embrião de Galinha , Clonagem Molecular , Fibroblastos/metabolismo , Humanos , Fatores Reguladores de Interferon , Interferon Tipo I/biossíntese , Interferon Tipo I/genética , Dados de Sequência Molecular , Proteínas Proto-Oncogênicas c-rel/fisiologia , RNA Mensageiro/biossíntese , Homologia de Sequência de Aminoácidos , Distribuição Tecidual , Ativação Transcricional , Transfecção
10.
Mol Cell Biol ; 17(12): 7328-41, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9372964

RESUMO

The oncoprotein v-Rel, a member of the Rel/NF-kappaB family of transcription factors, induces neoplasias and inhibits apoptosis. To identify differentially regulated cellular genes and to evaluate their relevance to transformation and apoptosis in v-Rel-transformed cells, mRNA differential display has been used. One of the recovered cDNAs corresponds to a gene that was highly expressed in v-Rel-transformed fibroblasts. Analysis of the isolated full-length cDNA of a chicken inhibitor-of-apoptosis protein (ch-IAP1) revealed that it encodes a 68-kDa protein that is highly homologous to members of the IAP family, such as human c-LAP1. Like other IAPs, ch-IAP1 contains the N-terminal baculovirus IAP repeats and C-terminal RING finger motifs. Northern blot analysis identified a 3.3-kb ch-IAP1 transcript expressed at relatively high levels in the spleen, thymus, bursa, intestine, and lungs. Expression of v-Rel in fibroblasts, a B-cell line, and spleen cells up-regulated the expression of ch-IAP1. In contrast, ch-IAP1 expression levels were low in chicken cell lines transformed by several other unrelated tumor viruses. ch-IAP1 was expressed predominantly in the cytoplasm of the v-Rel-transformed cells. ch-IAP1 suppressed mammalian cell apoptosis induced by the overexpression of the interleukin-1-converting enzyme. Expression of exogenous ch-IAP1 in temperature-sensitive v-Rel transformed spleen cells inhibited apoptosis of these cells at the nonpermissive temperature. Collectively, these results suggest that ch-IAP1 is induced during the v-Rel-mediated transformation process and functions as a suppressor of apoptosis in v-Rel-transformed cells.


Assuntos
Apoptose/fisiologia , Proteínas/fisiologia , Proteínas Oncogênicas de Retroviridae/fisiologia , Sequência de Aminoácidos , Animais , Apoptose/genética , Sequência de Bases , Caspase 1 , Linhagem Celular Transformada , Galinhas , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/fisiologia , Primers do DNA/genética , DNA Complementar/genética , Expressão Gênica , Humanos , Proteínas Inibidoras de Apoptose , Dados de Sequência Molecular , Proteínas Oncogênicas v-rel , Reação em Cadeia da Polimerase , Proteínas/genética , RNA Mensageiro/genética , Proteínas Oncogênicas de Retroviridae/genética , Homologia de Sequência de Aminoácidos , Temperatura , Distribuição Tecidual , Ubiquitina-Proteína Ligases
11.
Oncogene ; 14(24): 2881-97, 1997 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-9205096

RESUMO

The oncogene v-rel of Reticuloendotheliosis virus, strain T, is derived from an avian c-rel proto-oncogene. c-rel encodes a member of the Rel/NF-kappaB family of transcription factors. The highly oncogenic v-Rel differs from c-Rel which has low transforming potential by the acquisition of numerous mutations. In this manuscript, we demonstrate that the oncogenic mutations in v-Rel directly alter the ability of this protein to bind to DNA. Electrophoretic mobility shift analysis with Rel proteins synthesized in vitro as well as isolated from nuclei of Rel expressing cells showed that three mutation clusters, present in the N-terminus, the center and the C-terminus of v-Rel, altered three different aspects of DNA binding. In contrast, the oncogenic C-terminal deletion of 118 amino acids present in v-Rel had almost no influence on its DNA binding. The N-terminal mutation cluster altered the kappaB DNA-binding specificity of the v-Rel oncoprotein relative to c-Rel. The mutation Met-20-->Thr was found to be principally responsible for this alteration. The second mutation cluster was responsible for increased binding of v-Rel to all the kappaB sites examined presumably because it stabilized v-Rel homodimers. This alteration in DNA binding was mapped to the group of two mutations within the cluster. In contrast, the third mutation cluster in the C-terminus of v-Rel destabilized the binding of v-Rel to all of the kappaB sites examined. This is the first indication that regions outside the Rel Homology Region can participate in the control of binding of the c-Rel protein to DNA. The three mutation clusters examined contributed to the tumorigenic potential of v-Rel with the relative strength decreasing with their position from the N-terminus to the C-terminus. These results suggest that the oncogenic mutations in v-Rel cooperate and enable v-Rel to form nuclear complexes with aberrant DNA-binding properties that may directly alter gene expression and DNA replication resulting in the transformation of the cell.


Assuntos
DNA Viral/metabolismo , Proteínas de Ligação a DNA/metabolismo , Mutação , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Animais , Sítios de Ligação , Núcleo Celular/metabolismo , Galinhas , Sondas de DNA , Oncogenes , Mapeamento de Peptídeos , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-rel , Vírus da Reticuloendoteliose/genética , Sensibilidade e Especificidade , Perus
12.
J Virol ; 69(6): 3369-80, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7745683

RESUMO

The c-rel proto-oncogene encodes a member of the Rel/NF-kappa B family of transcription factors. The oncogenic viral form, v-rel, transduced by avian reticuloendotheliosis virus T, induces lymphoid tumors. v-Rel transformation may be mediated directly by binding of v-Rel to cognate DNA sites, resulting in altered gene expression, and/or indirectly by releasing Rel/NF-kappa B transcription factors from cytoplasmic retention molecules, resulting in their translocation to the nucleus and the inappropriate expression of genes under kappa B control. v-Rel-transformed cell lines of different phenotypes contained v-Rel as well as endogenous kappa B DNA-binding proteins in nuclear extracts. Kinetic analysis with avian leukosis virus-transformed B-cell lines expressing v-Rel or c-Rel indicated that the presence of endogenous kappa B DNA-binding proteins in the nucleus is temporally correlated with the relocalization of v-Rel to the cytoplasm. Supershift analysis of these DNA-binding complexes revealed that v-Rel was present in all of the nuclear DNA-binding complexes heterodimerized with c-Rel, NF-kappa B1, and other proteins. In contrast, c-Rel-transformed cells exhibited a less-complex pattern of nuclear kappa B DNA-binding complexes, and the nuclear appearance of these endogenous complexes was not observed. Studies with c-/v-Rel hybrids suggest that the induction of the endogenous kappa B DNA-binding complexes is the result of the mutations in the C-terminal region of the Rel homology (RH) domain of v-Rel. Moreover, v-Rel differed from c-Rel in its DNA-binding specificity. The altered DNA-binding specificity of v-Rel was associated with mutations located in the N-terminal part of the RH domain of v-Rel. These results suggest that two different regions of v-Rel (both located in the RH domain) influence the formation of kappa B DNA-binding complexes differently.


Assuntos
Proteínas de Ligação a DNA/genética , NF-kappa B/genética , Proteínas Oncogênicas de Retroviridae/genética , Animais , Sequência de Bases , Biopolímeros , Linhagem Celular Transformada , Núcleo Celular/metabolismo , Galinhas , Proteínas de Ligação a DNA/metabolismo , Dados de Sequência Molecular , Mutação , NF-kappa B/metabolismo , Oligodesoxirribonucleotídeos , Proteínas Oncogênicas v-rel , Ligação Proteica , Proteínas Oncogênicas de Retroviridae/metabolismo
13.
J Virol ; 68(4): 2039-50, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8138989

RESUMO

v-rel is a viral oncogene that evolved from turkey c-rel, an NF-kappa B-related transcription factor. Numerous structural alterations record the evolutionary selection of v-rel and distinguish it from c-rel. To evaluate the biological significance of these alterations, we constructed a set of five c/v-rel hybrids in which three mutation clusters (c-Rel amino acids 1 to 97,222 to 302, and 328 to 598) were differentially distributed. These constructs, in addition to parental v-rel and c-rel and two C-terminal deletion mutants of c-rel, were expressed from a retroviral vector. An analysis of cells infected with each of the nine viruses revealed that mutations in all three domains contributed to the ability of v-rel to induce two endogenous c-rel target genes, major histocompatibility complex (MHC) class I and class II, in the B-cell line DT95 as well as MHC class II in normal splenocytes. The analysis revealed a strong nonlinear correlation between the ability of a Rel protein to induce expression of MHC proteins and its capacity to produce splenic tumors and establish in vitro transformation. This correlation is consistent with the hypothesis that v-rel transforms by constitutively altering expression of genes regulated by c-rel and in this way simulates events associated with immune response-linked proliferation of cells of hematopoietic origin. Further, the 16 carboxy-terminal amino acids of c-Rel were identified as a domain responsible for producing a cytotoxic and/or cytostatic effect in DT95. Because this effect is likely to differentially influence induction of MHC expression and tumorigenesis/transformation, it may represent one factor that contributes to the nonlinearity of their correlation.


Assuntos
Transformação Celular Neoplásica , Regulação Neoplásica da Expressão Gênica , Antígenos de Histocompatibilidade/biossíntese , Neoplasias Experimentais/imunologia , Oncogenes/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Oncogênicas de Retroviridae/genética , Animais , Linfócitos B/citologia , Linfócitos B/patologia , Sequência de Bases , Evolução Biológica , Embrião de Galinha , Galinhas/genética , Citotoxicidade Imunológica , Análise Mutacional de DNA , Dados de Sequência Molecular , Proteínas Oncogênicas v-rel , Proteínas Proto-Oncogênicas c-rel , Proteínas Recombinantes de Fusão/genética , Vírus da Reticuloendoteliose Aviária/genética , Baço/citologia , Baço/patologia
14.
J Virol ; 68(4): 2371-82, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8139023

RESUMO

The c-rel proto-oncogene belongs to the NF-kappa B/rel and I kappa B gene families, which regulate several inducible processes, including self-defense/repair and embryogenesis. Transduction of the c-rel transcription factor by the avian retrovirus resulted in the formation of a highly oncogenic virus, reticuloendotheliosis virus strain T (REV-T), that encodes the oncogene v-rel. To examine the oncogenic potential of c-rel, we inserted it into a REV-T-based retroviral vector, rescued virus [REV-C(CSV)], and infected 1-day-old chicks. All birds developed tumors, and all cell lines established from REV-C-induced tumors expressed c-rel proteins that lacked C-terminal sequences. These proteins, responsible for both in vivo and in vitro cell proliferation, were apparently selected for their oncogenic potential. In order to examine the cooperation of C-terminal deletions with other oncogenic alterations in vivo, point mutations present in the N-terminal and middle regions of v-rel were analyzed by a similar protocol. The data obtained support four conclusions. (i) c-rel proteins bearing any of three single-amino-acid mutations present in the N-terminal portion of v-rel were sufficiently oncogenic to induce tumor development in the absence of additional mutations. (ii) Combining a mutation from the N-terminal region of v-rel with a deletion of the C-terminal sequences of c-rel increases the oncogenicity of the protein in an additive manner. (iii) Mutations present in the middle of v-rel cooperated synergistically with C-terminal deletions to produce highly transforming viruses. (iv) Deletion of c-rel produced a variety of transforming rel proteins with sizes that extended from 42 to 65 kDa. The most frequently isolated rel deletion was 62 kDa in size. To examine the basis for the selection of different rel mutants, their ability to induce immunoregulatory surface receptors was analyzed. The data revealed a correlation between the induction capacity of these mutants and their corresponding contribution to in vivo tumorigenic potential. Moreover, an analysis of the subcellular localization of different rel proteins revealed an inverse correlation between the size of the protein and the proportion in the nucleus of lymphoid cells.


Assuntos
Neoplasias Experimentais/genética , Proteínas Proto-Oncogênicas/genética , Proto-Oncogenes/genética , Alpharetrovirus/genética , Animais , Evolução Biológica , Linhagem Celular , Transformação Celular Neoplásica , Galinhas , Antígenos de Histocompatibilidade/biossíntese , Interleucina-2/biossíntese , Tecido Linfoide/citologia , Mutação , Proteínas Oncogênicas v-rel , Plasmídeos/genética , Proteínas Proto-Oncogênicas c-rel , Proteínas Oncogênicas de Retroviridae/genética , Deleção de Sequência , Transformação Genética
15.
J Virol ; 68(1): 308-19, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8254742

RESUMO

The c-rel gene is a member of NF-kappa B/rel family of transcription factors that regulate expression of a variety of immunoregulatory molecules. The viral oncogene, v-rel, is a truncated and mutated form of the turkey c-rel gene expressed by reticuloendotheliosis virus, strain T. In this study, we demonstrated that three avian immunoregulatory receptors, major histocompatibility (MHC) antigens class I and class II as well as the interleukin-2 receptor (IL-2R), were induced on the surface of splenic tumor cells isolated from chickens infected with reticuloendotheliosis virus, strain T. All cell lines derived from splenic tumors expressed these three proteins. Their expression also correlated with the appearance of endogenous c-rel during a graft-versus-host reaction. In vitro, both c-rel and v-rel induced MHC class I, MHC class II, and IL-2R on an avian B-lymphoid cell line, DT95, and a T-lymphoid cell line, MSB-1. Quantitative kinetic analysis demonstrated both the accumulation of MHC class II mRNA and the appearance of surface MHC class II protein in response to the synthesis of either v-rel or c-rel. We show that v-rel induced the expression of MHC class II in the avian B-cell lines DT40 and DT95 more rapidly than c-rel and that, several weeks after infection, v-rel induced MHC class II as much as 50-fold more efficiently than c-rel. Finally, in vitro infection of splenocytes with retroviruses that express v-rel or c-rel induced MHC class I, MHC class II, and IL-2R expression. Quantitative analysis confirmed that p59v-rel was consistently more efficient at inducing expression of all three immunoregulatory receptors than exogenous p68c-rel. These data suggest that during tumor development, v-rel functions to induce (or suppress) the expression of genes similarly induced (or suppressed) by c-rel. The observations reported in this study are not in agreement with a model in which v-rel promotes tumor development by functioning as a dominant negative mutant of c-rel. In contrast, these findings support the hypothesis that lymphocyte immortalization and tumor development are the result, at least in part, of the capacity of v-rel to function as a dominant positive mutant that induces expression of genes normally regulated by c-rel.


Assuntos
Regulação Neoplásica da Expressão Gênica , Proteínas Proto-Oncogênicas/imunologia , Receptores Imunológicos/biossíntese , Proteínas Oncogênicas de Retroviridae/imunologia , Animais , Linfócitos B/imunologia , Transformação Celular Viral , Galinhas , Genes MHC Classe I/fisiologia , Genes MHC da Classe II/fisiologia , Doença Enxerto-Hospedeiro/imunologia , Tecido Linfoide/imunologia , Tecido Linfoide/microbiologia , Proteínas Oncogênicas v-rel , Proteínas Proto-Oncogênicas c-rel , RNA Mensageiro/biossíntese , Receptores de Interleucina-2/biossíntese , Retroviridae/crescimento & desenvolvimento , Baço/imunologia , Baço/microbiologia , Células Tumorais Cultivadas
16.
J Virol ; 69(1): 403-13, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7983736

RESUMO

The v-Rel oncogene induces the expression of major histocompatibility complex class I and II proteins and the interleukin-2 receptor more efficiently than does c-Rel (R. Hrdlicková, J. Nehyba, and E. H. Humphries, J. Virol. 68:308-319, 1994). The kinetics with which these immunoregulatory receptors are induced in B- and T-lymphoid cell lines and chicken embryo fibroblast cultures expressing c-Rel or v-Rel have been examined. v-Rel induced the expression of major histocompatibility complex classes I and II and interleukin-2 receptor more efficiently than did c-Rel at later times after infection. In all three cell types, this increased efficiency was accompanied by a shift in the majority of v-Rel from the nucleus of the cytoplasm. The concomitant relocalization of v-Rel was also demonstrated during the in vitro transformation of spleen cells. The translocation coincided with increased steady-state levels of I kappa B-alpha. Coninfection by retroviral vectors expressing v-Rel, I kappa B-alpha, or NF-kappa B1 demonstrated that either I kappa B-alpha can contribute to the shift of v-Rel to the cytoplasmic compartment. The induction of nfkb1 and Ikba mRNA and the stabilization of I kappa B-alpha by v-Rel were shown to be responsible for these effects. In comparison with c-Rel, the expression of v-Rel was associated with lower levels of transcription of these genes. However, the ability of v-Rel to stabilize I kappa B-alpha remained unchanged. The ability of v-Rel to stabilize I kappa B-alpha but poorly induce Ikba mRNA expression relative to c-Rel may play a role in regulating gene expression, thereby leading to transformation.


Assuntos
NF-kappa B/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Oncogênicas de Retroviridae/metabolismo , Fatores de Transcrição , Animais , Transporte Biológico , Linhagem Celular , Núcleo Celular/metabolismo , Embrião de Galinha , Galinhas , Citoplasma/metabolismo , Genes MHC da Classe II , Cinética , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Proteínas Oncogênicas v-rel , Proteínas Proto-Oncogênicas/metabolismo , RNA Mensageiro/genética , Receptores de Interleucina-2/genética , Frações Subcelulares/metabolismo , Fator de Transcrição RelB
17.
J Biol Chem ; 273(52): 35201-7, 1998 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-9857058

RESUMO

The c-rel proto-oncogene product, c-Rel, belongs to the Rel/NF-kappaB transcription factor family, which regulates a large variety of cellular functions. The activation of NF-kappaB involves the degradation of the inhibitor, IkappaB, through the ubiquitin-proteasome (Ub-Pr)-mediated pathway. Here we report that the turnover of c-Rel is also regulated by the Ub-Pr pathway, thus adding another level of complexity to the regulation of NF-kappaB. High molecular weight ubiquitinated c-Rel conjugates are detected in cells and accumulate in cells treated with proteasome inhibitors. In a cell-free in vitro degradation assay, c-Rel is degraded specifically through the Ub-Pr pathway. N-terminally truncated c-Rel is readily degraded, implying the dispensability of N-terminal sequence; in contrast, a series of deletion mutants missing C-terminal sequences display a reduced susceptibility to the degradation. Interestingly, the sequence between residues 118 and 171 of c-Rel, i.e. the region immediately following the c-Rel/v-Rel homology domain, appears to play an important role in mediating ubiquitin conjugation and the subsequent degradation. Together with our previous study showing an elevated tumorigenic potential for C-terminally truncated mutants, our data suggest that the C-terminal domain of c-Rel plays an important role in mediating c-Rel degradation and growth control.


Assuntos
Cisteína Endopeptidases/metabolismo , Complexos Multienzimáticos/metabolismo , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Ubiquitinas/metabolismo , Células 3T3 , Animais , Aves , Células COS , Cisteína Endopeptidases/efeitos dos fármacos , Inibidores de Cisteína Proteinase/farmacologia , Vírus Linfotrópico T Tipo 1 Humano/crescimento & desenvolvimento , Linfoma de Células B/metabolismo , Camundongos , Complexos Multienzimáticos/efeitos dos fármacos , Fragmentos de Peptídeos/metabolismo , Complexo de Endopeptidases do Proteassoma , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-rel , Proteínas Recombinantes/metabolismo , Especificidade por Substrato , Linfócitos T/metabolismo , Linfócitos T/virologia
18.
Mol Cell Biol Res Commun ; 4(5): 266-75, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11529676

RESUMO

Rel/NF-kappaB proteins are eukaryotic transcription factors that control the expression of genes involved in a large variety of cellular processes. Rel proteins share a highly conserved DNA-binding/dimerization domain called the Rel Homology (RH) domain. We have constructed and characterized a composite cDNA encoding most of the chicken RelB transcription factor. The predicted chicken RelB protein has a high degree of sequence similarity to other vertebrate RelB proteins within the RH domain, but is much less conserved outside this domain. Chicken RelB does not bind DNA as a homodimer, but forms DNA-binding heterodimers with NF-kappaB p50 or p52. Overexpressed chicken RelB localizes to the nucleus in chicken embryo fibroblasts, and the nonconserved C-terminal sequences of chicken RelB contain a transactivation domain that functions in chicken and mouse fibroblasts. Thus, chicken RelB has functional properties similar to other vertebrate RelB proteins. However, Western blotting of diverse chicken tissues indicates that chicken RelB is more widely expressed than mammalian RelB.


Assuntos
Galinhas , Perfilação da Expressão Gênica , Proteínas Proto-Oncogênicas/metabolismo , Elementos de Resposta/genética , Fatores de Transcrição/metabolismo , Ativação Transcricional , Transporte Ativo do Núcleo Celular , Sequência de Aminoácidos , Animais , Sequência de Bases , Western Blotting , Células Cultivadas , Clonagem Molecular , Sequência Conservada , DNA/genética , DNA/metabolismo , Fibroblastos , Mamíferos , Microscopia de Fluorescência , Dados de Sequência Molecular , Especificidade de Órgãos , Ligação Proteica , Proteínas Proto-Oncogênicas/química , Proteínas Proto-Oncogênicas/genética , Homologia de Sequência de Aminoácidos , Fator de Transcrição RelB , Fatores de Transcrição/química , Fatores de Transcrição/genética
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