RESUMO
In two patients with subacute sclerosing panencephalitis (SSPE) of 10 and 25 months duration we demonstrated by immunohistochemistry the presence of measles-virus nucleocapsid antigen (MVNA) in CD68+ cells and astrocytes of brain tissues. In both cases, CD68+ hematogenous monocyte/ macrophages and perivascular microglial cells (Mphi) were found infiltrating the brain parenchyma, and often partially or completely invested by perivascular reactive astrocytes expressing glial fibrillary acidic protein (GFAP). Mphi with cytoplasmic MVNA were often seen in the Virchow-Robin spaces and in close association with perivascular astrocytes, which often also contained MVNA+ intracytoplasmic inclusions. Reactive astrocytosis was more severe in the patient with long-standing illness, and a correspondingly elevated number of strongly GFAP+ MVNA+ or MVNA- perivascular binucleated astrocytes was observed. An uptake of MVNA+ cell debris by reactive astrocytes was evident in areas of white matter displaying extensive demyelination and necrosis. Taken together, these observations seem to indicate that the brain infiltration by Mphi carrying measles virus could represent one pathway of virus entry and dissemination in the central nervous system. Virus transfer to perivascular astrocytes via cell-to-cell contacts with infected macrophages is also suggested.
Assuntos
Antígenos Virais/isolamento & purificação , Encéfalo/patologia , Encéfalo/virologia , Vírus do Sarampo/isolamento & purificação , Panencefalite Esclerosante Subaguda/virologia , Antígenos CD , Antígenos de Diferenciação Mielomonocítica , Astrócitos/virologia , Movimento Celular , Criança , Pré-Escolar , Proteína Glial Fibrilar Ácida/isolamento & purificação , Humanos , Imuno-Histoquímica , Macrófagos/virologia , Masculino , Microglia/virologia , Estudos Retrospectivos , Panencefalite Esclerosante Subaguda/patologiaRESUMO
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
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.