Assuntos
Adenocarcinoma/imunologia , Antígenos de Neoplasias/imunologia , Antígenos de Superfície/imunologia , Colo/imunologia , Neoplasias Colorretais/imunologia , Glicoproteínas de Membrana/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Antineoplásicos/imunologia , Especificidade de Anticorpos , Biomarcadores Tumorais/imunologia , Cromatografia em Gel , Epitélio/imunologia , Epitopos/imunologia , Fezes , Humanos , Mucosa Intestinal/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Peso Molecular , Neoplasias/imunologia , Especificidade de Órgãos , Células Tumorais Cultivadas/imunologiaRESUMO
A colorectal antigen (IOR-C2) was characterized by a monoclonal antibody produced against the colon cancer cell line SW1116. By immunohistochemical staining the antigen was abundant and strongly expressed in epithelium of normal colon whereas colorectal carcinomas showed a more variable and heterogenous reactivity to the antibody (IOR-C2). Radioimmunoprecipitates of SW1116 cell homogenates showed a 160-200 kD band in SDS gels. Physicochemical characterization indicate that at least two IOR-C2 reactive sites are present on the antigen tested and that it is mainly an 0-linked glycoprotein carbohydrate chain which can also be N-linked to the protein. The expression of IOR-C2 mimics that of the colon associated antigen (CAA) and NCC-CO-450 antigen but is distinct from these with regard to its expression in carcinomas as well as its physicochemical characteristics.
Assuntos
Antígenos de Neoplasias , Neoplasias Colorretais/imunologia , Animais , Anticorpos Monoclonais , Biomarcadores Tumorais/imunologia , Epitopos , Humanos , Hibridomas/imunologia , Imuno-Histoquímica , Mucosa Intestinal/imunologia , Camundongos , Células Tumorais Cultivadas/imunologiaRESUMO
The epidermal growth factor receptor was analyzed in the membrane fraction from a series of human breast carcinomas using a radioligand assay. The results were compared to immunostaining with monoclonal antibodies on tissue sections. All tumors with detectable receptor levels as measured by ligand binding showed a positive staining with monoclonal antibodies. In such tumors more than 50 percent of the cells were receptor positive with varying intensity. Tumors classified as receptor negative with the radioligand assay could be divided into two major groups based on their immunostaining. The largest group showed no reactivity with monoclonal antibodies. In a second smaller group, a positivity was observed in small clusters of tumor cells while the majority of cells were negative. The staining intensity in such clusters was usually low. It seems possible that this heterogenous expression of the epidermal growth factor receptor is of significance with respect to clonal selection in tumor spreading.
Assuntos
Neoplasias da Mama/química , Carcinoma Intraductal não Infiltrante/química , Receptores ErbB/análise , Anticorpos Monoclonais/imunologia , Receptores ErbB/imunologia , Feminino , Humanos , Imuno-HistoquímicaRESUMO
Inmunizando con la linea del cáncer del colon SW1116 (pobremente diferenciado), se obtuvo el anticuerpo monoclonal IORC2 empleando la técnica convencional de generación de hibridomas. El anticuerpo monoclonal IORC2 muestra un reconocimiento preferencial por el tejido epitelial en cortes fijados e incluidos en parafina, según se evidencia, empleando el sistema de detección avidina-peroxidasa-complejo (Amersham, U.K.). Se observa una reacción intensa en las lineas de cáncer del colon SW1116 y en los tumores derivados del epitelio glandular, especialmente los adenocarcinomas del colon y la mucosa normal del colon. También se observa reacción en un bajo por ciento de células del intestino delgado y del epitelio bronquial. No hubo reacción en los tejidos de origen nervioso, muscular y hematopoyético. Las aplicaciones potenciales del anticuerpo monoclonal IORC2 en el manejo del cáncer colorrectal humano se discuten
Assuntos
Anticorpos Monoclonais , Neoplasias do Colo , CubaRESUMO
Using a new anti-CEA (CB-CEA-1) murine monoclonal antibody, the expression of carcinoembryonic antigen (CEA) was studied in normal, premalignant and malignant human adult tissues with particular emphasis on colorectal mucosa. The CB-CEA-1 epitope was poorly expressed in normal adult tissues but was consistently found in colon cancers and adenomas in distinctive immunohistochemical patterns. Some apical staining was found with CB-CEA-1 in cells of normal colon mucosa whereas colon adenocarcinomas had a predominantly cytoplasmic staining pattern. Colonic adenomas presented a varied staining pattern. Some showed apical staining, others a CEA distribution pattern similar to that of adenocarcinomas, particularly those with a villous component. Our findings indicate a differential expression of CB-CEA-1 in adenoma cells in relation to their potential for malignant transformation. The possible usefulness of this Mab defined epitope for diagnostic and therapeutic purposes is indicated.
Assuntos
Adenocarcinoma/metabolismo , Antígeno Carcinoembrionário/metabolismo , Neoplasias do Colo/metabolismo , Lesões Pré-Cancerosas/metabolismo , Adenocarcinoma/patologia , Anticorpos Monoclonais/imunologia , Antígeno Carcinoembrionário/imunologia , Neoplasias do Colo/diagnóstico , Neoplasias do Colo/patologia , Humanos , Imuno-Histoquímica , Lesões Pré-Cancerosas/diagnóstico , Lesões Pré-Cancerosas/patologiaRESUMO
El factor de crecimiento epidérmico (EGF), es un polipéptido mitogénico para células de origen epitelial y mesenquimatoso; sin embargo, tiene un efecto inhibitor de la proliferación in vitro de las células que tienen un número muy elevado de receptores de EGF en su superficie. Resultados precedentes de nuestro laboratorio demostraron que este efecto inhibidor también puede obtenerse in vivo, en tumores humanos creciendo como xenotransplantes en ratones atímicos. En este artículo presentamos las primeras evidencias clínicas del efecto del EGF en carcinomas humanos. Se trataron 10 carcinomas de piel (9 pacientes) mediante la aplicación diaria tópica de una crema que contenía 10*g/g de EGF humano recombinante. Durante las tres semanas de tratamiento no se obtuvo ninguna evidencia de progresión tumoral, al contrario, la mitad de las lesiones mostraron una respuesta objetiva favorable. Cuatro pacientes refirieron mejoría subjetiva intensa, dada por alivio del dolor y recuperación funcional de las estructuras afectadas por el tumor. En cuatro pacientes se registraron notables cambios histológicos, dados por una disminución en la proporción de células tumorales en el tejido, un aumento en la reacción estromal y la aparición de infiltrado inflamatorio. La ampliación del concepto de hormono-dependencia, para incluir la regulación de tumores por factores de crecimiento, implica como corolario la aplicación del campo de la terapia hormonal, para incluir el tratamiento con factores de crecimiento o sus análogos. Estos resultados preliminares son la primera evidencia de que estos conceptos pueden ser aplicables en la clínica.
Assuntos
Humanos , Carcinoma/tratamento farmacológico , Fator de Crescimento Epidérmico/uso terapêutico , Neoplasias Cutâneas/tratamento farmacológicoRESUMO
En el presente trabajo se compara la purificación de anticuerpos monoclonales de ratón de diferentes clases y subclases (IgG1, IgG2 e IgM) por cromatografía de adsorción en hidroxiapatita (BioRad) y en hidroxiapatita-Ultrogel (LKB). Se analizaron los factores capacidad de adsorción, rendimiento, tiempo de corrida (velocidad de flujo), reciclaje y capacidad de enlazamiento específicos de los anticuerpos obtenidos inmediatamente después de la purificación y posterior a su almacenamiento. Se concluye que la cromatografía de adsorción en hidroxiapatita, y en específico, luego de que esta sustancia acoplada a un soporte adecuado (HA Ultrogel), constituye un método fácil, sencillo, rápido y eficiente para la purificación de anticuerpos monoclonales
Assuntos
Camundongos , Animais , Anticorpos Monoclonais/isolamento & purificação , Cromatografia por Troca Iônica , HidroxiapatitasRESUMO
Fine structure and function are closely related in the cells of the different tissues. For this reason a comparative study combining histochemical techniques and scanning electron microscopy can result a potentially useful tool in the search for cell markers of preneoplastic stages of the colon mucosa. With this purpose, samples of normal colon mucosa, adenomatous polyps and adenocarcinomas obtained by colonoscopy were studied by histochemical techniques for the detection of epithelial mucosubstances and by scanning electron microscopy. Differences were shown in the architectural arrangement of the colon epithelium between the normal mucosa, the adenocarcinoma and the polyps studied, while between tubular an tubulovillous adenomas no marked differential ultrastructural features were found. Acid mucosubstances distribution pattern showed that sialomucin predominated in the colon mucosa harboring a carcinoma and in the tubulo-villous polyps as well as in the mucosa remote from adenocarcinoma and from the two cases of familial polyposis coli histologically considered as tubulo-villous adenomas. On the other hand tubular adenomas and normal mucosa showed a predominance of sulfomucin.
Assuntos
Neoplasias do Colo/metabolismo , Lesões Pré-Cancerosas/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma/ultraestrutura , Adenoma/metabolismo , Adenoma/ultraestrutura , Biópsia , Carcinoma/metabolismo , Carcinoma/ultraestrutura , Colo/metabolismo , Colo/ultraestrutura , Neoplasias do Colo/ultraestrutura , Histocitoquímica , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/ultraestrutura , Microscopia Eletrônica de Varredura , Lesões Pré-Cancerosas/ultraestruturaRESUMO
The first 7 cases of histologically and cytochemically confirmed Burkitt's lymphoma have recently been studied in Cuba. Some of them presented with facial bone involvement and high anti-Epstein-Barr virus (EBV) antibody titers characteristic of endemic African cases. Others showed features of nonendemic cases. The distribution of patients in these two groups may be in relation to the behavior of the healthy Cuban population with respect to the EBV virus.