RESUMEN

Expression of intercellular adhesion molecule-1 (ICAM-1) appears to be important to the development of bronchial hyperresponsiveness and eosinophilia in Ascaris sensitized monkeys. Beta 1-integrins are expressed on epithelial cells, and may contribute to adherence of epithelial cells to the basement membrane. The aim of this study was to determine whether adhesion receptor expression was altered in human asthmatic bronchial epithelium. Using monoclonal antibody staining, we have examined the expression of ICAM-1 and the alpha 1-alpha 6-subunits of the beta 1-integrin family in bronchial mucosal biopsies from 33 asthmatic and 13 nonasthmatic subjects. The epithelium was positive for ICAM-1 in 26 out of 33 asthmatics, although negative in all 13 nonasthmatics. ICAM-1 expression was not associated with bronchial responsiveness or with medication requirements. Beta 1-integrin staining showed that alpha 2-, alpha 3- and alpha 6-subunits stained the epithelium in all cases. Alpha 4 staining was weakly positive in the epithelium in five asthmatics. Alpha 5 staining was weak in asthmatics and normals. Alpha 4 and alpha 6-subunits also stained inflammatory cells. Epithelial upregulation of ICAM-1 is present in asthma. Beta 1-integrins with alpha 2-, alpha 3- and alpha 6-subunits appear to be constitutively expressed in bronchial epithelium.

Asunto(s)

RESUMEN

Nonisotopic in situ hybridization has been used to investigate the role of Epstein-Barr virus (EBV) in the aetiology of pediatric Hodgkin's disease. Sections from 24 cases arising in children under the age of 15 years were hybridised with digoxigenin-labelled probes for both EBV and cytomegalovirus, and reactive sites were identified by a sensitive three-layer immunoperoxidase technique. EBV was identified in Reed-Sternberg and mononuclear Hodgkin's cells in five samples (21%). No samples were positive when the cytomegalovirus probe was employed. The specific identification of EBV in the malignant cells of Hodgkin's disease arising in children lends further support for a role of EBV in the aetiology of this disorder.

Asunto(s)

RESUMEN

Interactions between cells and extracellular matrices are mediated in part by a family of heterodimeric molecules known as integrins. We have investigated, using immunohistology, the distribution of six integrin alpha sub-units in normal breast tissue and 26 breast carcinomas. Alpha-1 integrin (collagen/laminin receptor sub-unit) was detected in myoepithelium, but not in luminal epithelium nor in most (20/26) carcinomas. Its expression on fibroblasts was enhanced in desmoplastic stroma. Both benign and malignant epithelium showed uniform positive staining for alpha-2 (collagen receptor sub-unit) and for alpha-3 (collagen/fibronectin/laminin receptor sub-unit). All epithelium was negative for alpha-4 (sub-unit of a fibronectin receptor). Epithelial staining for alpha-5 (fibronectin receptor sub-unit) was weak in all samples. Alpha-6 (sub-unit of two integrin laminin receptors) showed conspicuous changes in all invasive carcinomas. In normal tissues, there was weak staining of epithelial cytoplasm with alpha-6 antibody and moderate cell membrane staining. Strongest staining was present in a basement membrane distribution. In carcinomas, loss of cytoplasmic and cell membrane staining was variable, but basal membrane staining was diminished or absent in all tumours. Loss of basal membrane staining for alpha-6 integrin corresponded closely to loss of immunoreactivity for its ligand laminin in invasive breast cancer.

Asunto(s)

RESUMEN

Non-isotopic in situ hybridization employing digoxigenin-labelled DNA probes has been used to localize Epstein-Barr virus (EBV) in 55 cases of Hodgkin's disease (HD). The virus was found in Reed-Sternberg (RS) and mononuclear Hodgkin's cells in nine patients (16 per cent). Further samples taken at different times from three patients also showed the presence of EBV in the malignant cell population. Estimations of the number of EBV genomes present per cell suggested wide variations between different patients, but relatively constant amounts in different samples from the same patient. These findings are compatible with a stable infection of the neoplastic cells and support the notion that EBV may play a role in the development of HD in these patients. We also found evidence for the presence of EBV in a small percentage of non-neoplastic cells in 8 of the 55 samples. This suggests that isolation of EBV from HD tissue does not always signify a pathogenetic role for the virus. Furthermore, it is apparent that a high percentage of HD tissues do not contain demonstrable EBV, and the virus is therefore unlikely to be a causative agent for all cases of HD.

Asunto(s)

RESUMEN

A highly sensitive non-isotopic in situ hybridisation technique was developed for the localisation of Epstein-Barr virus (EBV) in paraffin wax embedded tissue sections. The method uses a repeated sequence of the EBV genome as a probe, labelled with the novel reporter molecule, digoxigenin. The method can identify individual copies of EBV by detection of both EBV DNA and highly localised RNA transcripts. A combination of careful proteolytic digestion of tissue sections, high temperature denaturation of probe and target DNA, and sensitive immunocytochemical detection are used to attain single copy sensitivity. The technique is quicker and simpler to perform than some other methods used for the identification of EBV, and provides simultaneous morphological information which cannot be obtained by methods using tissue extracts. This method permits the investigation of the role of EBV in neoplastic conditions of lymphoid and epithelial cells, and may prove valuable in determining the sites of latent virus in healthy subjects.

Asunto(s)

RESUMEN

The polymerase chain reaction was applied to the analysis of DNA contained in archival paraffin wax embedded material. DNA suitable for the reaction was obtained from these tissues by simple extraction methods, without previous dewaxing of tissue sections. When compared with unfixed material, the reaction efficiency was compromised, so that an increased number of amplification cycles were required to produce equivalent amounts of amplified product. This in turn led to an increase in amplification artefacts, which can be minimised by a simple modification of the standard reaction. Amplification of relatively large DNA fragments was not always successful, and it seems prudent to bear this in mind when designing oligonucleotide primers which are to be used for the amplification of archival material. The efficiency of the procedure can be improved by dividing the amplification cycles into two parts: this reduces the amount of reagent needed, is relatively simple and inexpensive, and can be performed in one working day.

Asunto(s)

RESUMEN

Partial myoepithelial differentiation is common in simple epithelial hyperplasia (epitheliosis) of the breast but functional myoepithelial differentiation with basement membrane production is exceedingly rare. A peculiar change of hyaline globules within benign epithelial hyperplasia has been recognised before as "collagenous spherulosis" and type IV collagen has been shown by immunohistochemistry. Another seven cases are described which show the presence of laminin and collagens IV and III within the proliferation. Electron microscopy examination of two cases using material retrieved from the wax block showed varying degrees of myoepithelial differentiation of the cells immediately surrounding the spherules and basal lamina material, including mature collagen fibrils in one case. The degree of myoepithelial differentiation of the cells surrounding the spherules seemed to correlate with the differing types and amounts of extracellular matrix in the spherule. Histopathologists should be aware of this rare change as it may be misinterpreted as in situ carcinoma.

Asunto(s)

RESUMEN

One hundred and one consecutive patients with newly diagnosed stage I Hodgkin's disease (HD) received treatment at St Bartholomew's Hospital, between 1968 and 1987, with a median follow-up of 12 years. Eleven patients have been excluded from detailed analysis because they either received involved field radiotherapy (RT) or radiotherapy with chemotherapy or were lost to follow-up. Actuarial analysis predicts 78% to be alive and without relapse of Hodgkin's disease at 15 years. Ninety evaluable patients (clinical stage (CS) 24; pathological stage (PS) 66) received either mantle or inverted 'Y' RT and form the basis of this analysis. The median age was 33 years (63 men, 27 women). Histology at presentation was nodular sclerosing (39), lymphocytic predominant (27) or mixed cellularity (24). The presenting site was neck (78), axilla (6) groin (4) and mediastinum (2). Complete remission was achieved in all evaluable patients, the actuarial proportion in remission being 75% at 15 years. Factors predictive of a prolonged remission were pathological staging versus clinical staging (P = 0.02) and lymph node size less than 3 cm (P = 0.04). Actuarial overall survival in these 90 patients was 75% at 15 years and none of the above factors correlated with survival. Relapse of HD has occurred in 18 patients (5 within RT field, 10 without and 3 in both). Second remission was achieved in 15/18. The actuarial rate of second remission and survival was 40% at 10 years. Sixteen patients have died, 7 of Hodgkin's disease, 7 of unrelated causes and 2 of second malignancy. A further 3 patients who developed second malignancy are still alive. At 15 years the actuarial mortality related to HD was 12%. These results confirm the importance of long follow up to assess the efficacy of primary therapy.

Asunto(s)

Asunto(s)

RESUMEN

The clinical features of two patients with hairy cell leukemia involving the mediastinum are described. Both patients presented with acute chest pain 2-3 months prior to diagnosis being made. In one patient mediastinal disease was recorded only by computerized tomography of the thorax. There was good response of mediastinal disease to alpha-interferon in both patients, in spite of persisting bone marrow involvement with hairy cell leukemia.

Asunto(s)

Asunto(s)

Asunto(s)

RESUMEN

Fifty-four cases of invasive carcinoma of breast were immunostained for fibronectin and laminin. They included 36 cases of invasive ductal carcinoma and 18 cases of invasive lobular carcinoma. Although there was some heterogeneity within tumours, it was found that whilst the majority of ductal carcinomas (31/36) had abundant fibronectin at cell/stroma boundaries or diffusely throughout stroma, a substantial proportion of lobular carcinomas (12/18) had very little (P less than 0.001). This difference could not be related to differences in laminin immunoreactivity, which was most commonly scanty or absent in both tumour types. It is postulated that the characteristic infiltration pattern of lobular carcinoma may be attributed in part to paucity of stromal fibronectin.

Asunto(s)

RESUMEN

A panel of antibodies that recognize antigens that survive fixation and conventional processing have been applied to 43 cases of Hodgkin's disease and five cases of large cell anaplastic lymphoma. Reed-Sternberg cells in all five cases of nodular lymphocyte predominance Hodgkin's disease were positive with leucocyte common (CD45) and B-cell antibodies, and negative with LeuM1 (CD15) and BerH2 (CD30) antibodies. In other types of Hodgkin's disease, Reed-Sternberg cells were positive with BerH2 in all cases, positive with LeuM1 in 63% of cases (with enzymic predigestion), positive with at least one B-cell antibody in 29% of cases and positive for CD45 in 8% of cases. In 19% of all cases, Reed-Sternberg cells were positive for epithelial membrane antigen and in 93% they were positive with TAL1B5 (anti-class II MHC). No case showed immunoreactivity with anti-T-cell antibodies. The patterns of immunoreactivity of large cell anaplastic lymphoma were similar, except that none was positive with B-cell antibodies and three were positive with T-cell antibodies. All five were positive with BerH2 (CD30) and TAL1B5. Comparison of the results with those seen in other cases of non-Hodgkin's lymphoma indicates that, with the currently available reagents, this immunohistological profile cannot be used as the sole diagnostic discriminant of these conditions; this must still be based upon careful morphological assessment.

Asunto(s)

RESUMEN

Reagents that recognize antigens on lymphoid cells in fixed and wax-embedded sections have been applied to a series of cases of non-Hodgkin's lymphomas. The panel consisted of MB1, 4KB5 (CD45r), LN1, L26 and MB2 which recognize antigens expressed predominantly on B-lymphocytes; UCHL1 and MT1 which recognize antigens expressed on T-lymphocytes and myeloid cells; antibodies recognizing the non-lineage antigens LeuM1 (CD15), BerH2 (CD30), anti-EMA; anti-lysozyme and MAC 387 which detect antigens present on some macrophages; and finally TAL1B5 (class II MHC), CAM 5.2 (low molecular weight cytokeratin) and PD7/26 + 2B11(CD45). Two hundred and four cases of non-Hodgkin's lymphoma have been studied, of which 158 had been fully characterized on frozen sections. The series was biased towards high-grade (n = 108) and T-cell (n = 44) tumours and these were largely prospectively accrued. It was found that discrimination between B-cell and T-cell lymphomas can be reliably achieved using these reagents and that a small panel (CD45, L26, MB2, MT1, UCHL1) is adequate for this purpose. Using the full range of reagents it is not possible to subdivide cases into groups that correspond with morphological subtypes of lymphoma. Although paraffin section immunohistochemistry is of value, the diagnosis of lymphoproliferative disorders must still be based upon the assessment of well fixed, carefully prepared tissue sections using conventional tinctorial methods.

Asunto(s)

RESUMEN

P component is present in amyloid deposits, normal serum, and normal tissues in relation to elastic fibres. Its pathological role in inflammatory synovitis was investigated. Its distribution was determined immunohistologically in 33 synovia: 15 rheumatoid; seven osteoarthritic; seven traumatic controls; and four infected biopsy specimens. P component was present in two circumscribed distributions: extracellular fibrils in dense fibroelastic tissue of the more fibrotic synovia; and in the arterial wall, where it was confined to a single elastic lamina in some cases and in others showed reduplication and fragmentation. These were not related to amyloid material. It shows no disease specificity, but P component categorises the nature of the pathological reaction and is typically in biopsy specimens showing the development of chronic fibrosis. There was close codistribution of P component with elastic tissue, though this was not absolute. P component had a different distribution from C reactive protein (in synovial lining cell layer), and fibronectin, which was absent from fibrotic areas. Understanding the pathological interactions of P component may help elucidate why some synovial reactions remain inflammatory and other progress to chronic fibrosis.

Asunto(s)

RESUMEN

In this study the ultrastructural localization of antigens recognized by novel antibodies that allow the recognition of lymphoid antigens in conventionally fixed and wax-embedded sections was investigated. MT1, MB1, and UCHL1 recognize antibodies restricted to the cell membrane, whereas the antigen recognized by MB2 is present only in the cytoplasm. These distributions are different from that of immunoreactivity with TAL 1B5 (anti-HLA DR), which is present both on the cell membrane and in the cytoplasm. The significance of these findings is discussed.

Asunto(s)

RESUMEN

The immunohistochemical reactivity of a monoclonal antibody, anti-L-35, on a wide range of tissues is described. Anti-L-35 showed a high specificity for known and presumptive cells of the mononuclear phagocyte system including monocytes, sinus histiocytes, tangible body macrophages, interdigitating reticulum cells, Kupffer cells, alveolar macrophages, microglia, synoviocytes and Langerhans cells. Anti-L-35 also stained osteoclasts in fetal and adult bone including osteoclast-like giant cells of the giant-cell tumour of bone. Anti-L-35 did not react with any other cell type in the tissues screened apart from renal proximal tubular epithelium and megakaryocytes. This study has shown that L-35 is not restricted to activated T-cells, as previously reported, and provides further immunohistochemical evidence that monocytes, macrophages and osteoclasts contain common cellular antigens.

Asunto(s)

RESUMEN

The monoclonal antibody Ki67 recognizes an antigen expressed in all phases of the cell cycle except Go. It has been used in 141 biopsies from 138 patients with non-Hodgkin's lymphoma to identify proliferating cells in histological sections. A Ki67 index (the number of Ki67 positive tumour cells divided by the sum of Ki67 positive and negative tumour cells) has been derived by counting 1000 cells in each case. A correction for the presence of non-tumour cells has been incorporated by counting non-tumour cells in serial sections stained with a panel of other antibodies. A very strong correlation between a low Ki67 index (less than 20 per cent) and low grade histology and a high Ki67 index (greater than 20 per cent) and high grade histology was found (Chi2 = 98.0). Ninety-one patients could be analysed for survival and those with low grade lymphoma (n = 38) who had a relatively high Ki67 index (greater than 5 per cent) had a worse survival than those with an index of less than 5 per cent (p less than 0.05). In contrast, there was a trend for those patients with high grade disease with a very high Ki67 index (greater than 80 per cent) to have a better survival than those with a lower index (less than 80 per cent). The patients with high grade disease who achieved complete remission or good partial remission and had a Ki67 index of less than 80 per cent were more likely to relapse than those with an index of greater than 80 per cent (p less than 0.04). These findings could not be explained by the effect of other prognostic factors such as age, stage, or serum albumin. While the use of Ki67 immunostaining has potential drawbacks, it appears to be a simple and reproducible method of determining a tumour proliferative index which provides relevant clinical data.

Asunto(s)

RESUMEN

The murine monoclonal antibody Ki67 recognizes a nuclear antigen present in all phases of the cell cycle except Go and can be used with a simple indirect immunohistochemical technique to demonstrate cell proliferation in tissue sections. This antibody was applied to 37 unselected renal biopsies showing a wide variety of histological appearances. Ki67-positive nuclei were seen most frequently in tubular epithelium in acute tubulo-interstitial pathology, particularly in renal allograft rejection. Tubular epithelial staining ranged from 0 to 10% of cells. In chronic nephropathies few tubular cells were stained. Staining was seen in glomerular crescents, but was rare in glomerular tufts except those that showed mesangial proliferation where occasional cells stained. This study demonstrates that information regarding cellular proliferation in renal biopsies can be easily obtained using Ki67 immunostaining. This is likely to be a useful investigative tool and may provide clinically useful information.

Asunto(s)