RESUMO
The "cage" convulsant [(35)S]t-butylbicyclophosphorothionate ([(35)S]TBPS) binds with high affinity to specific sites "at" or "near" a ?-amino-butyric acid (GABA)-gated chloride channel according to current hypothesis. We now report that pretreatment of membranes with 2,3-butanedione, an arginine-specific reagent, causes a dose- and time-dependent decrease in the number of [(35)S]TBPS binding sites. No decrease occurs when membranes are pretreated with 2,3-butanedione in the presence of picrotoxinin. Binding of [(35)S]TBPS to the remaining sites occurs with the same characteristics as binding to the untreated receptor population.
RESUMO
Benzodiazepine GABA-ionophore receptor complex ligands showed persistent modulation of the chloride ionophore, labeled by [(35)S]TBPS, even after receptor complex extensive purification. GABA caused inhibition of [(35)S]TBPS binding, while benzodiazepine agonists increased and benzodiazepine inverse agonists decreased the specific [(35)S]TBPS binding to the purified receptor. When GABA binding sites were occupied by the neurotransmitter benzodiazepine receptor agonists and antagonists reversed their effects clonazepam in fact inhibited and ?-carboline ethyl ester increased [(35)S]TBPS binding in the presence of GABA. The antagonist flumazenil showed no effect both in the presence or absence of GABA.
RESUMO
A new version of the Rational-Experiential Inventory (REI), which measures rational and experiential thinking styles and includes subscales of self-reported ability and engagement, was examined in two studies. In Study 1, the two main scales were independent, and they and their subscales exhibited discriminant validity and contributed to the prediction of a variety of measures beyond the contribution of the Big Five scales. A rational thinking style was most strongly and directly related to Ego Strength, Openness, Conscientiousness, and favorable basic beliefs about the self and the world, and it was most strongly inversely related to Neuroticism and Conservatism. An experiential thinking style was most strongly directly related to Extraversion, Agreeableness, Favorable Relationships Beliefs, and Emotional Expressivity, and it was most strongly inversely related to Categorical Thinking, Distrust of Others, and Intolerance. In Study 2, a rational thinking style was inversely related and an experiential thinking style was unrelated to nonoptimal responses in a game of chance. It was concluded that the new REI is a significant improvement over the previous version and measures unique aspects of personality.
Assuntos
Inventário de Personalidade , Psicometria/métodos , Pensamento , Adulto , Análise de Variância , Comportamento de Escolha , Análise Fatorial , Feminino , Jogo de Azar , Humanos , Relações Interpessoais , Masculino , Motivação , New England , Reprodutibilidade dos Testes , Fatores Sexuais , Ajustamento SocialRESUMO
To explain why the depressive realism effect has been found in trivial, artificial laboratory but not in more realistic or emotionally engaging situations, the authors hypothesized that depressed people overcompensate for a tendency toward maladaptive experiential (intuitive) processing by exercising excessive rational control in trivial situations. In more consequential situations, they are unable to control their maladaptive experiential processing because it is excessive, or their rational control is insufficient, or both. As predicted, a subclinically depressed group (n = 39) made more optimal decisions than a nondepressed control group (n = 36) under trivial conditions, and the groups converged under more consequential conditions, with the depressed group responding less and the control group more optimally. Also, the depressed group reported engaging in less rational processing and in more maladaptive experiential processing in everyday life than did the control group.
Assuntos
Cognição , Mecanismos de Defesa , Depressão/psicologia , Ego , Teste de Realidade , Análise de Variância , Feminino , Humanos , Controle Interno-Externo , Intuição , Masculino , Motivação , Teoria PsicológicaRESUMO
Two studies provide evidence for the reliability and validity of a new self-report measure of individual differences in intuitive-experiential and analytical-rational thinking based on cognitive-experiential self-theory (CEST). The Rational-Experiential Inventory (REI) was constructed to measure the 2 independent processing modes with a modified Need for Cognition Scale (NFC, J.T. Cacioppo & R.E. Petty, 1982) and a new scale, Faith in Intuition (FI). In Study 1, a factor analysis yielded 2 orthogonal factors corresponding to NFC and FI. Although heuristic processing was determined primarily by FI, NFC also contributed to heuristic responding, in line with CEST. The relation of FI and NFC to coping ability also was examined. In Study 2, the factor structure of the REI was replicated (N = 973). NFC and FI were differentially related to measures of personality, adjustment, achievement, and interpersonal relations.
Assuntos
Pensamento , Cognição , Feminino , Humanos , Masculino , Processos Mentais , Fatores SexuaisRESUMO
The authors report their clinical experience in 100 cases in which various kinds of drainage were used. They outline the best present techniques, when it is wished to apply this free drainage in the abdominal cavity, at the end of the operation.
Assuntos
Drenagem/métodos , Procedimentos Cirúrgicos Operatórios/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Drenagem/efeitos adversos , Drenagem/instrumentação , Drenagem/estatística & dados numéricos , Feminino , Humanos , Incidência , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Sucção/efeitos adversos , Sucção/instrumentação , Sucção/métodos , Sucção/estatística & dados numéricos , Procedimentos Cirúrgicos Operatórios/efeitos adversos , Procedimentos Cirúrgicos Operatórios/estatística & dados numéricos , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/etiologiaRESUMO
Extra-oral implants have been used for well-defined application for nearly 20 years; for tupoorting maxillo-facial prostheses and for bone anchored hearing aids (BAHA). In both of these applications, the bone-anchored prostheses support transcutaneous abutments. It is the junction between the implant and the abutment which ensures, given certain preconditions, the permanent percutaneous connection (PPC). The authors describe the two types of implants currently in use-intra- and juxta-osseous implants. They then give a brief description of the two techniques. The advantages and disadvantages of each system are summarised, as well as the conditions required for permanent survival of a PPC.
Assuntos
Próteses e Implantes , Placas Ósseas , Parafusos Ósseos , Humanos , Cirurgia PlásticaAssuntos
Cromossomos Humanos Par 3/genética , Cromossomos Humanos Par 5/genética , Regulação Leucêmica da Expressão Gênica , Leucemia Mieloide/tratamento farmacológico , Leucemia Mieloide/genética , Proteínas Nucleares/genética , Proteínas de Fusão Oncogênica/genética , Doença Aguda , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Humanos , Proteínas Nucleares/biossíntese , Nucleofosmina , Proteínas de Fusão Oncogênica/análise , Proteínas de Fusão Oncogênica/biossíntese , Frações Subcelulares/química , Translocação Genética/genéticaRESUMO
The authors refer on Salmonella species isolated from carriers, in USL 13 country, during the period of five years 1984-1988 in the microbiological laboratories of S.M.P. USL 13. N. 1240 Salmonella strains were isolated. N. 62 serotypes have been recognized of which about 77% were of the groups B, C1, E1. The trial shows a high positivity of more rare serotypes especially in summer period.
Assuntos
Infecções por Salmonella/epidemiologia , Salmonella/classificação , Salmonella/isolamento & purificação , Portador Sadio , Fezes/microbiologia , Humanos , Itália/epidemiologia , Estações do Ano , SorotipagemRESUMO
For extra-oral implants, the difficulty is not simply the surgical technique, similar to that used for intra-oral implants. The real problem is to insert the implant at a specific position and with a proper alignment. The final cosmetic result is directly related to correct insertion of the implant and its anchors. We demonstrate the importance of a tight collaboration between the surgeon and the prosthesis, before, after and often during the intervention for obtaining a satisfactory result.
Assuntos
Relações Interprofissionais , Próteses e Implantes , Desenho de Prótese , Cirurgia Bucal , Face/cirurgia , Humanos , Planejamento de Assistência ao Paciente , Assistência Perioperatória , Cuidados Pós-Operatórios , Cuidados Pré-Operatórios , Relações Profissional-Paciente , Próteses e Implantes/psicologiaRESUMO
The respective indications for oral or extra-oral implants lead to no confusion: stabilization of dental prostheses for the first, stabilization of maxilo-facial epitheses for the others. We demonstrate that the complementarity of the two types of implants can prove to be very useful in maintaining the maxillary dental prosthesis and the epithesis in a case of severe loss of facial substance affecting particularly the pre-maxilla. This complementary characteristic made it possible to recover fairly rapidly phonation and deglutition, and to remedy somewhat the esthetic damage. In other words to create the essential conditions for a return to everyday life.
Assuntos
Carcinoma de Células Escamosas/cirurgia , Implantação Dentária Endóssea , Neoplasias Faciais/cirurgia , Implante de Prótese Maxilofacial , Idoso , Carcinoma de Células Escamosas/reabilitação , Planejamento de Prótese Dentária , Enucleação Ocular , Neoplasias Faciais/reabilitação , Humanos , Lábio/cirurgia , Masculino , Maxila/cirurgia , Invasividade Neoplásica , Nariz/cirurgia , Órbita/cirurgia , Planejamento de Assistência ao Paciente , Desenho de Prótese , Zigoma/cirurgiaRESUMO
The BCL-6 gene is frequently involved in translocations occurring at the 3q27 locus and is rearranged in approximately 30% of diffuse large cell lymphomas and in a small fraction of follicular lymphomas. The BCL-6 gene encodes for a Kruppel-type zinc-finger protein, the cell/tissue expression and function of which is unknown. In this study, we describe a new monoclonal antibody (PG-B6) that is specifically directed against a fixative-sensitive epitope on the amino-terminal region of the BCL-6 protein. By immunocytochemical analysis, BCL-6 localizes in the nucleus where PG-B6 staining gives a microgranular/diffuse pattern with exclusion of the nucleoli. The main reactivity of PG-B6 in tonsil and spleen is with the nuclei of germinal center B cells, whereas B cells within the mantle and marginal zones do not express BCL-6. No other lymphoid cells in the tonsil express BCL-6 except for a subset of CD3+/CD4+ intrafollicular and interfollicular T cells. A few lymphoid cells of unknown phenotype express BCL-6 in the thymus. Extra-lymphoid BCL-6 expression includes a weak nuclear positivity of epithelia. In non-Hodgkin's lymphomas, BCL-6 expression parallels that observed in normal lymphoid compartments, eg, expression in germinal center-derived tumors (follicular and diffuse large cell lymphomas), but not in mantle cell and marginal zone lymphomas. In most diffuse large cell lymphomas, the BCL-6 protein is expressed at high levels in cases with or without BCL-6 gene rearrangements. These findings indicate that BCL-6 expression is specifically regulated during B lymphocyte development and suggest that BCL-6 may play a role during B cell differentiation in the germinal center.
Assuntos
Anticorpos Monoclonais/imunologia , Linfócitos B/metabolismo , Proteínas de Ligação a DNA/imunologia , Proteínas de Ligação a DNA/metabolismo , Tecido Linfoide/metabolismo , Linfoma de Células B/metabolismo , Proteínas Proto-Oncogênicas/imunologia , Proteínas Proto-Oncogênicas/metabolismo , Fatores de Transcrição/imunologia , Fatores de Transcrição/metabolismo , Animais , Especificidade de Anticorpos , Tecido Linfoide/citologia , Linfoma de Células B/patologia , Linfoma não Hodgkin/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Proto-Oncogênicas c-bcl-6 , Valores de ReferênciaRESUMO
PG-M3 is a new monoclonal antibody (MoAb) specifically directed against a peptide sequence located in the aminoterminal region of the human PML protein. PML gene fuses with the retinoic acid receptor alpha (RAR alpha) gene during the t(15; 17) chromosomal translocation of acute promyelocytic leukemia (APL). The epitope recognized by PG-M3 is species-specific and fixative-resistant and is shared by most PML isoforms and PML/RAR alpha fusion proteins. PML is consistently located within the nucleus, although a minority of cells (about 20%), both in vitro and in vivo, show positivity for PML also in the cytoplasm. The nuclear staining pattern of PG-M3 varies from speckled (cells other than APL) to micropunctate (APL cells). Although two physiologically expressed PML isoforms are detectable by immunocytochemistry only or predominantly in the cytoplasm of transfected cells, the cytoplasmic localization of PML is a property also shared by the PML isoforms that predominantly localize to the nuclei. Immunohistologic analysis of normal human tissues with the PG-M3 MoAb showed variable PML expression, with the highest levels of the protein in postmitotic, differentiated cell types, such as endothelial cells, epithelia, and tissue macrophages, especially activated ones. In keeping with this in vivo finding, PML appears strongly upregulated in the U937 promonocyte cell line after exposure to agents that induce monocyte/macrophage activation (interferon gamma) or maturation (vitamin D3 and transforming growth factor beta 1).
Assuntos
Anticorpos Monoclonais/imunologia , Endotélio Vascular/metabolismo , Epitélio/metabolismo , Regulação da Expressão Gênica , Macrófagos/metabolismo , Proteínas de Neoplasias , Proteínas Nucleares , Fatores de Transcrição/imunologia , Células 3T3 , Sequência de Aminoácidos , Animais , Aves , Linhagem Celular Transformada , Núcleo Celular/metabolismo , Chlorocebus aethiops , Colecalciferol/farmacologia , Citoplasma/metabolismo , Endotélio Vascular/citologia , Células Epiteliais , Epitopos/imunologia , Humanos , Ativação de Macrófagos/efeitos dos fármacos , Mamíferos , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Monócitos/metabolismo , Proteínas de Fusão Oncogênica/genética , Fragmentos de Peptídeos/imunologia , Proteína da Leucemia Promielocítica , Coelhos , Receptores do Ácido Retinoico/genética , Receptor alfa de Ácido Retinoico , Especificidade da Espécie , Fatores de Transcrição/biossíntese , Fatores de Transcrição/química , Fatores de Transcrição/genética , Transfecção , Fator de Crescimento Transformador beta/farmacologia , Células Tumorais Cultivadas , Proteínas Supressoras de TumorRESUMO
A new anti-macrophage monoclonal antibody (PG-M1) was produced by immunizing BALB/c mice with fresh spleen cells from a patient with Gaucher's disease. PG-M1 reacts strongly with a fixative-resistant epitope of an intracytoplasmic molecule, selectively expressed by virtually all macrophages of the human body. Although attempts to immunoprecipitate the molecule recognized by PG-M1 have failed so far, the reactivity of the antibody with COS-1 and WOP cells transfected with a human complementary DNA clone encoding for the CD68 antigen suggests that PG-M1 is a new member of the CD68 cluster. However, unlike other CD68 antibodies (KP1, EBM11, etc.), which react with both macrophages and myeloid cells, PG-M1 detects a fixative-resistant epitope on the macrophage-restricted form of the CD68 antigen. In 957 routinely fixed, paraffin-embedded samples, PG-M1 showed a more restricted reactivity with elements of the monocyte/macrophage lineage than the previously described monoclonal antibodies MAC-387 (anti-calgranulins), KP1 (CD68) and Ki-M1P. Among hematological malignancies, PG-M1 only labels acute leukemias of M4 and M5 type and rare examples of malignant histiocytosis/true histiocytic sarcoma. In contrast, acute leukemias of the M1, M2, M3, M6, M7, and L1-L3 types, non-Hodgkin's lymphomas, and Hodgkin and Reed-Sternberg cells of Hodgkin's disease are consistently PG-M1-negative. In the daily diagnostic practice, PG-M1 seems to be particularly valuable for the diagnosis of myelomonocytic or monocytic leukemia and neoplasms of true histiocytic origin in routine paraffin sections.
Assuntos
Anticorpos Monoclonais/imunologia , Antígenos CD/imunologia , Antígenos de Diferenciação Mielomonocítica/imunologia , Epitopos , Fixadores/farmacologia , Macrófagos/imunologia , Formação de Anticorpos , Antígenos CD/análise , Antígenos de Diferenciação Mielomonocítica/análise , Linhagem Celular , DNA/genética , Resistência a Medicamentos , Doenças Hematológicas/imunologia , Sistema Hematopoético , Humanos , Inflamação/imunologia , Doenças Linfáticas/imunologia , Neoplasias/imunologia , Testes de Precipitina , Valores de Referência , TransfecçãoRESUMO
A new monoclonal antibody (MUM1p) was used to study the cell/tissue expression of human MUM1/IRF4 protein, the product of the homologous gene involved in the myeloma-associated t(6;14) (p25;q32). MUM1 was expressed in the nuclei and cytoplasm of plasma cells and a small percentage of germinal center (GC) B cells mainly located in the "light zone." Its morphologic spectrum ranged from that of centrocyte to that of a plasmablast/plasma cell, and it displayed a phenotype (MUM1(+)/Bcl-6(-)/Ki67(-)) different from that of most GC B cells (MUM1(-)/Bcl-6(+)/Ki67(+)) and mantle B cells (MUM1(-)/Bcl-6(-)/Ki67(-)). Polymerase chain reaction (PCR) analysis of single MUM1(+ )cells isolated from GCs showed that they contained rearranged Ig heavy chain genes with a varying number of V(H) somatic mutations. These findings suggest that these cells may represent surviving centrocytes and their progeny committed to exit GC and to differentiate into plasma cells. MUM1 was strongly expressed in lymphoplasmacytoid lymphoma, multiple myeloma, and approximately 75% of diffuse large B-cell lymphomas (DLCL-B). Unlike normal GC B cells, in which the expression of MUM1 and Bcl-6 were mutually exclusive, tumor cells in approximately 50% of MUM1(+) DLCL-B coexpressed MUM1 and Bcl-6, suggesting that expression of these proteins may be deregulated. In keeping with their proposed origin from GC B cells, Hodgkin and Reed-Sternberg cells of Hodgkin's disease consistently expressed MUM1. MUM1 was detected in normal and neoplastic activated T cells, and its expression usually paralleled that of CD30. These results suggest that MUM1 is involved in the late stages of B-cell differentiation and in T-cell activation and is deregulated in DLCL-B. (Blood. 2000;95:2084-2092)
Assuntos
Anticorpos Monoclonais , Linfócitos B/metabolismo , Proteínas de Ligação a DNA/metabolismo , Plasmócitos/metabolismo , Linfócitos T/metabolismo , Fatores de Transcrição/metabolismo , Linfócitos B/imunologia , Biomarcadores Tumorais/metabolismo , Western Blotting , Linhagem Celular , Homólogo 5 da Proteína Cromobox , Epitopos , Células HeLa , Humanos , Região Variável de Imunoglobulina/metabolismo , Imuno-Histoquímica , Fatores Reguladores de Interferon , Células Jurkat , Linfonodos/metabolismo , Linfoma/metabolismo , Mieloma Múltiplo/metabolismo , Plasmócitos/imunologia , Proteínas Recombinantes de Fusão/metabolismo , Linfócitos T/imunologia , Fatores de Tempo , TransfecçãoRESUMO
The RING-finger promyelocytic leukemia (PML) protein is the product of the PML gene that fuses with the retinoic acid receptor-alpha gene in the t(15; 17) translocation of acute promyelocytic leukemia. Wild-type PML localizes in the nucleus with a typical speckled pattern that is a consequence of the concentration of the protein within discrete subnuclear domains known as nuclear bodies. Delocalization of PML from nuclear bodies has been documented in acute promyelocytic leukemia cells and suggested to contribute to leukemogenesis. In an attempt to get new insights into the function of the wild-type PML protein and to investigate whether it displays an altered expression pattern in neoplasms other than acute promyelocytic leukemia, we stained a large number of normal and neoplastic human tissues with a new murine monoclonal antibody (PG-M3) directed against the amino-terminal region of PML. As the PG-M3 epitope is partially resistant to fixatives, only cells that overexpress PML are detected by the antibody in microwave-heated paraffin sections. Among normal tissues, PML was characteristically up-regulated in activated epithelioid histiocytes and fibroblasts in a variety of pathological conditions, columnar epithelium in small active thyroid follicles, well differentiated foamy cells in the center of sebaceous glands, and hypersecretory endometria (Arias-Stella). Interferons, the PML of which is a primary target gene, and estrogens are likely to represent some of the cytokines and/or hormones that may be involved in the up-regulation of PML under these circumstances. In keeping with this concept, we found that PML is frequently overexpressed in Hodgkin and Reed-Sternberg cells of Hodgkin's disease, a tumor of cytokine-producing cells. Among solid tumors, overexpression of PML was frequently found in carcinomas of larynx and thyroid (papillary), epithelial thymomas, and Kaposi's sarcoma, whereas carcinomas of the lung, thyroid (follicular), breast, and colon were frequently negative or weakly PML+. We did not observe any changes in the levels of PML expression as the lesion progressed from benign dysplasia to carcinoma. Our immunohistological data are consistent with the hypothesized growth suppressor function of PML and strongly suggest that PML expression levels are likely to be modulated by a variety of stimuli, including cytokines and hormones.
Assuntos
Núcleo Celular/química , Núcleo Celular/patologia , Transformação Celular Neoplásica/patologia , Proteínas de Neoplasias , Proteínas Nucleares , Fatores de Transcrição/biossíntese , Sequência de Aminoácidos , Carcinoma/química , Carcinoma/patologia , Transformação Celular Neoplásica/química , Epitélio/metabolismo , Humanos , Leucemia Promielocítica Aguda/genética , Tecido Linfoide/química , Tecido Linfoide/patologia , Linfoma/química , Linfoma/patologia , Dados de Sequência Molecular , Especificidade de Órgãos , Proteína da Leucemia Promielocítica , Sarcoma/química , Sarcoma/patologia , Proteínas Supressoras de TumorRESUMO
The BCL-6 gene encoding a nuclear-located Kruppel-type zinc finger protein is rearranged in about 30% diffuse large B-cell lymphomas and is expressed predominantly in normal germinal center B cells and related lymphomas. These findings suggest that BCL-6 may play a role in regulating differentiation of normal germinal center B cells and that its deregulated expression caused by rearrangements may contribute to lymphomagenesis. This prompted us to investigate the expression of the BCL-6 protein in Hodgkin's disease (HD), focusing on the nodular lymphocyte predominance subtype (NLPHD), which differs from classical HD by virtue of the B-cell nature of the malignant cell population (so-called L&H cells) and its relationship with germinal centers. Forty-one HD samples (19 NLPHD, 12 nodular sclerosis, and 10 mixed cellularity) were immunostained with the monoclonal antibodies PG-B6 and PG-B6p that react with a fixative-sensitive and a formalin-resistant epitope on the aminoterminal region of the BCL-6 gene product, respectively. Strong nuclear positivity for the BCL-6 protein was detected in tumor (L&H) cells in all cases of NLPHD. In contrast, BCL-6 was expressed only in a small percentage of Hodgkin and Reed-Sternberg cells in about 30% of classical HD cases. Notably, the nuclei of reactive CD3+/CD4+ T cells nearby to and rosetting around L&H cells in NLPHD were also strongly BCL-6+, but lacked CD40 ligand (CD40L) expression. This staining pattern clearly differed from that of classical HD, whose cellular background was made up of CD3+/CD4+ T cells showing the BCL-6-/CD40L+ phenotype. These results further support the concept that NLPHD is an histogenetically distinct, B-cell-derived subtype of HD and suggest a role for BCL-6 in its development.
Assuntos
Linfócitos B/metabolismo , Proteínas de Ligação a DNA/biossíntese , Regulação Neoplásica da Expressão Gênica , Doença de Hodgkin/metabolismo , Proteínas de Neoplasias/biossíntese , Células-Tronco Neoplásicas/metabolismo , Proteínas Proto-Oncogênicas/biossíntese , Fatores de Transcrição/biossíntese , Animais , Anticorpos Monoclonais/imunologia , Antígenos de Neoplasias/análise , Linfócitos B/patologia , Biomarcadores Tumorais/análise , Complexo CD3/análise , Antígenos CD4/análise , Ligante de CD40 , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/imunologia , Células-Tronco de Carcinoma Embrionário , Doença de Hodgkin/genética , Doença de Hodgkin/patologia , Humanos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Glicoproteínas de Membrana/análise , Camundongos , Camundongos Endogâmicos BALB C , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/imunologia , Células-Tronco Neoplásicas/patologia , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/imunologia , Proteínas Proto-Oncogênicas c-bcl-6 , Células de Reed-Sternberg/metabolismo , Células de Reed-Sternberg/patologia , Formação de Roseta , Subpopulações de Linfócitos T/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/imunologiaRESUMO
The t(2;5)(p23;q35) translocation associated with CD30-positive anaplastic large cell lymphoma results in the production of a NPM-ALK chimeric protein, consisting of the N-terminal portion of the NPM protein joined to the entire cytoplasmic domain of the neural receptor tyrosine kinase ALK. The ALK gene products were identified in paraffm sections by using a new anti-ALK (cytoplasmic portion) monoclonal antibody (ALKc) that tends to react more strongly than a previously described ALK1 antibody with the nuclei of ALK-expressing tumor cells after microwave heating in 1 mmol/L ethylenediaminetetraacetic acid buffer, pH 8.0. The ALKc monoclonal antibody reacted selectively with 60% of anaplastic large cell lymphoma cases (60 of 100), which occurred mainly in the first three decades of life and consistently displayed a T/null phenotype. This group of ALK-positive tumors showed a wide morphological spectrum including cases with features of anaplastic large cell lymphoma "common" type (75%), "lymphohistiocytic" (10%), "small cell" (8.3%), "giant cell" (3.3%), and "Hodgkin's like" (3.3%). CD30-positive large anaplastic cells expressing the ALK protein both in the cytoplasm and nucleus represented the dominant tumor population in the common, Hodgkin's-like and giant cell types, but they were present at a smaller percentage (often with a perivascular distribution) also in cases with lymphohistiocytic and small cell features. In this study, the ALKc antibody also allowed us to identify small neoplastic cells (usually CD30 negative) with nucleus-restricted ALK positivity that were, by definition, more evident in the small cell variant but were also found in cases with lymphohistiocytic, common, and "Hodgkin's-like" features. These findings, which have not been previously emphasized, strongly suggest that the neoplastic lesion (the NPM-ALK gene) must be present both in the large anaplastic and small tumor cells, and that ALK-positive lymphomas lie on a spectrum, their position being defined by the ratio of small to large neoplastic cells. Notably, about 15% of all ALK-positive lymphomas (usually of the common or giant cell variant) showed a cytoplasm-restricted ALK positivity, which suggests that the ALK gene may have fused with a partner(s) other than NPM. From a diagnostic point of view, detection of the ALK protein was useful in distinguishing anaplastic large cell lymphoma cases of lymphohistiocytic and small cell variants from reactive conditions and other peripheral T-cell lymphoma subtypes, as well as for detecting a small number of tumor cells in lymphohemopoietic tissues. In conclusion, ALK positivity appears to define a clinicopathological entity with a T/null phenotype ("ALK lymphomas"), but one that shows a wider spectrum of morphological patterns than has been appreciated in the past.
Assuntos
Linfoma Anaplásico de Células Grandes/patologia , Proteínas Tirosina Quinases/metabolismo , Quinase do Linfoma Anaplásico , Anticorpos Monoclonais/imunologia , Biomarcadores Tumorais , Western Blotting , Ensaio de Imunoadsorção Enzimática , Células HeLa/enzimologia , Sistema Hematopoético/enzimologia , Humanos , Imuno-Histoquímica , Leucemia Linfocítica Crônica de Células B/enzimologia , Leucemia Linfocítica Crônica de Células B/patologia , Linfoma Anaplásico de Células Grandes/enzimologia , Reação em Cadeia da Polimerase , Proteínas Tirosina Quinases/imunologia , Receptores Proteína Tirosina Quinases , Proteínas Recombinantes de Fusão/metabolismoRESUMO
The human BCL-6 gene, which is rearranged in approximately 30% of diffuse large B cell lymphomas, encodes a 706-amino-acid nuclear protein of the Kruppel-type zinc finger transcription factors mainly expressed in normal germinal center B cells and related lymphomas. Four monoclonal antibodies (PG-B6, PG-B6a, PG-B6p, and PG-B6m), specifically directed against the human BCL-6 protein, were generated by immunizing BALB/c mice with a recombinant protein corresponding to the BCL-6 amino-terminal region (amino acids 3 to 484). The PG-B6 monoclonal antibody reacted with a BCL-6 epitope sensitive to fixatives and preserved in all mammalian species. PG-B6a (a is for avian) recognized the most evolutionarily conserved BCL-6 epitope (expressed in all animal species including avian). PG-B6p (p is for paraffin) recognized a fixative-resistant epitope of BCL-6 that was detectable on paraffin sections after microwave heating in 1 mmol/L EDTA buffer. PG-B6m (m is for mantle) was the least specific monoclonal antibody as, in addition to BCL-6, it reacted with a yet undefined antigen selectively located in the cytoplasm of mantle and marginal zone B cells. All monoclonal antibodies detected strong nuclear expression of BCL-6 in follicular lymphomas, diffuse large B cell lymphomas, Burkitt's lymphomas, and nodular, lymphocyte-predominance Hodgkin's disease. In diffuse large B cell lymphomas, BCL-6 expression was independent of BCL-6 gene rearrangements and did not correlate with expression of other markers or the proliferation index. BCL-6 was not expressed in B-CLL, hairy cell leukemia, mantle-cell- and marginal-zone-derived lymphomas. Labeling of paraffin sections with PG-B6p proved useful for differentiating proliferation centers in B-CLL (BCl-2+/BCL-6-) from trapped germinal centers in mantle cell lymphomas (BCL-2-/BCL-6+) and for identifying neoplastic cells in cases of nodular, lymphocyte-predominance Hodgkin's disease. Because of their high specificity, wide reactivity in humans and animal species including avians (PG-B6a), and suitability for labeling routine paraffin sections (PG-B6p), the reagents described in this paper should prove valuable in both research and diagnostics.