ISSN:1062-3345    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Methods for processing human and animal tissues for immunohistochemistry are reviewed. Many different fixatives and processing schemes have been suggested to be optimal for immunohistochemistry. This reflects the multiplicity of antigens that, unfortunately, makes the construction of universally adoptable procedures impossible. Fixatives can be divided into two categories: coagulant and cross-linking. Coagulant fixatives, such as ethanol, are often used to preserve immunoreactivities of large proteins such as immunoglobulins, filament proteins, and receptors. They alter the dielectric constant of proteins and precipitate them. Coagulant fixatives do not react covalently with amino acids and therefore do not change the primary structure of proteins. Also, the secondary structure may be preserved, whereas tertiary structure (protein folding) may be changed. Lack of effects on primary and secondary protein structure may explain why coagulant fixatives preserve many protein epitopes. Low-molecular-weight material will often be extracted during coagulant fixation. Several dislocation artifacts have also been detected during coagulant fixation, and tissue shrinkage may present a problem. Aldehyde fixatives, such as formaldehyde and glutaraldehyde, preserve structure and immobilize antigens to a much greater degree than do coagulant fixatives. Cross-linking fixatives attack the primary structure of proteins and form cross-links and adducts that often involve amino, sulphydryl, and amide groups. This results in a much more profound effect on primary, secondary, and tertiary protein structure, but is necessary for optimized morphology and for immobilization of soluble antigens at their native sites. Formalin is by far the most commonly used cross-linking fixative for immunohistochemistry. The fact that formalin fixation is no single well-defined procedure is stressed, and the need for standardization in fixative concentration, time, temperature, pH, and osmolarity is emphasized. Although many antigenic structures are lost during formalin fixation, our studies show that it often is the combination of formalin and paraffin embedding that is the real culprit. Mild formalin fixation may thus be optimal for some sensitive antigens, but subsequent processing may result in extractions, superimposed ethanol fixation, and heat modifications. Thus, formalin fixation followed by cryo-protection and cryostat sectioning preserves a larger array of antigens than do formalin-paraffin procedures. Although it often is stated that a particular fixation preserves or destroys a certain antigen, this is not necessarily true. Thus, antibodies recognize only very small parts of antigens, and such epitopes may be affected differently by fixation. Thus, it has been possible to find “formalin-resistant antibodies” to many antigens that also work well on archival material. In other cases, chemical or enzymatic demasking procedures have successfully retrieved antigens that were “lost.” The bottom line, however, is still that tissue preparation is based mainly on trial and error and that no golden rules can be offered.

ISSN:1062-3345    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

A variety of antibodies detect the antigen defined by the cluster designation group 15 (CD15). These antibodies have been reported to be helpful in the diagnosis of many different diseases including leukemia, Hodgkin's disease, and non-Hodgkin's lymphoma, as well as aiding in the differential diagnosis between epithelial malignant mesothelioma and adenocarcinoma. In this review we describe the immunoreactivity of many of the CD15 antibodies, including MMA (Leu M1), anti-My1, C3D-1 (Dako-M1), VIM-D5, 1G10, MCS-1, anti-SSEA, and 3C4. The expression of the CD15 antigen in non-neoplastic human cells, leukemic cell lines and in neoplastic cells is reviewed.

ISSN:1062-3345    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Thirty-five cases of invasive breast carcinomas in formalin-fixed, paraffin-embedded tissue sections were examined and scored for estrogen receptor (ER) and progesterone receptor (PR) proteins, tumor vascularity as determined by factor VIII-associated antigen (factor VIII) immunostaining, and proliferative activity as determined by proliferating cell nuclear antigen (PCNA) immunoreactivity. There was a high correlation between the immunohistochemical (IHC) scores and biochemical values for both ER and PR (p< 0.001). The IHC analysis was able to detect more cases that were both ER and PR positive compared to the biochemical assay (58% vs. 48%). Comparison of tumor vascularity and PCNA IHC score revealed that carcinomas with greater neovascularization showed greater proliferative activity (p= 0.008). Carcinomas with higher PCNA scores and tumor vascularity were more likely to have metastasized to lymph nodes, but these associations were not statistically significant. These results indicate that markers with important prognostic significance such as ER and PR can be readily performed in routinely processed tissue sections, and that immunohistochemical analysis of tumor neovascularization and proliferation in routinely processed tissues may be useful in predicting the behavior of breast carcinomas.

ISSN:1062-3345    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Although the ligand-binding biochemical assay is currently the standard method for the determination of estrogen receptor, it is not readily reproducible, is often inaccurate, and requiresnot always availablefresh tissue. Immunohistochemical analysis of estrogen receptor in paraffin-embedded tissue has improved to a point where it is worth considering the feasibility of its use as a stand-alone technique. For this reason, we compared the results of the charcoal-dextran estrogen receptor assay with the immunohistochemical assay on routinely fixed, paraffin-embedded tumor samples from 166 patients with breast cancer. The results were analyzed for concordance between methods as well as for their individual predictive value for overall survival. At the statistically determined, prognostically optimal threshold of 20 fmol/mg total protein, the ligand-binding and immunohistochemical assay were in agreement in 156 cases (94%) with only 10 discrepancies. Six biochemically negative cases were positive by the immunohistologic method and were interpreted as true positives. Four of these were oligocellular tumors and stained strongly for estrogen receptor. Four cases were biochemically positive and negative by immunohistochemistry. These were interpreted as false negative by immunohistochemistry although they all were near the threshold of the ligand-binding technique and were highly cellular, suggesting a low level of receptorper cell.Analysis of overall survival for this series revealed that both methods provide statistically significant discrimination between high and low risk groups. These results confirm previous studies suggesting that the immunohistochemical method, when performed in adequately fixed, paraffin-embedded tissue is as or more accurate than the ligand-binding assay.

ISSN:1062-3345    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Thirty-seven carcinomas with histologically verified lymphatic vascular invasion were evaluated with five endothelial cell markers in order to test these markers for the objective documentation of the vascular invasion. The markers were factor VIII-related antigen (FVIII), BNH9 monoclonal antibody to H antigen,Ulex europaeusI lectin (UEA),Psophocarpus tetragonolobuslectin (PT), and CD34, a leukocyte antigen also present in endothelial cells. All of these markers stained small and medium-sized normal vessels approximately equally in formalin-fixed, routinely processed tissue. However, all except for FVIII had additional specificities. BNH9 also stained all erythrocytes. BNH9, UEA, and PT reacted with epidermis and some carcinomas. CD34 also stained peritumoral fibroblasts both around tumor nests and vessels, obscuring the labeling of vascular invasion spaces; therefore, this marker was not further evaluated. The four markers could detect the presence of invasive tumor cells in the confines of an immunohistochemically or lectin histochemically detectable vessel as follows: FVIII, 23/37 cases; BNH9, 28 cases; UEA, 30 cases; and PT, 21 cases. Obvious intravascular (lymphatic) spaces with deposits of tumor cells were commonly negative for vascular endothelial cell markers. This may result from antigenic or anatomic destruction of vascular endothelium, or from problems of specimen-to-specimen optimization of immunohistochemistry. Although the identification of endothelial cells directly underneath the invasive cells supports the presence of vascular invasion, such invasion cannot be ruled out by negative immunostainings for endothelial cell markers.

ISSN:1062-3345    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

The reactivity of BNH9 antibody, which recognizes a fixation-resistant blood group-related antigen, was compared with that of an antibody of the CD34 class (QBEND10) in 52 tumors of presumed endothelial cell origin. Relative specificities were simultaneously assessed in 132 tumors of other cellular origin. QBEND10 reacted with most Kaposi's sarcoma (20 of 25) and was superior to BNH9 (7 of 25) in reacting with early lesions of Kaposi's sarcoma. No significant difference was noted between the two antibodies in late lesions. The vasoformative proliferation was strongly labeled with QBEND10. BNH9 proved to be more consistent in reacting strongly with angiosarcoma (9 of 9) compared to focal and moderate staining intensities obtained with QBEND10 (8 of 9). Hemangiopericytoma reacted strongly with QBEND10 (5 of 5) whereas BNH9 did not. Both antibodies were equally and strongly reactive with epithelioid hemangio-endothelioma of the liver (3 of 3). No reactivity of QBEND10 was noted with lymphangioma, which showed moderate staining with BNH9. The expression of CD34 antigen recognized by QBEND10 in acute leukemias was expected, but the antibody was nonreactive with lymphomas and virtually all epithelial tumors of diverse origin. QBEND10 was found to react with approximately half of the tumors of smooth muscle origin. The usual reactivity of BNH9 with erythrocytes, a proportion of epithelial tumors, and anaplastic large-cell lymphomas was confirmed during this investigation. These antibodies provide advantages over currently available antibodies reacting with endothelial cells, and in the routine histopathological diagnosis of vascular tumors.

ISSN:1062-3345    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Spindle cell (sarcomatoid) carcinoma (SpCCa) of the upper aerodigestive tract is a biphasic tumor of controversial histogenesis exhibiting dual epithelial and mesenchymal malignant differentiation by light and electron microscopy. To characterize further the potential of these carcinomas for myogenic differentiation, we immunostained 26 biphasic SpCCa with antibodies to cytokeratin, vimentin, pan-muscle-specific actin (HHF-35), α-smooth muscle actin (1A4), sarcomeric muscle actin (polyclonal), and desmin. Cytokeratin was found in the spindle cell component of 42% of tumors, vimentin in 100%, and HHF-35 expression in 42%. Coexpression of cytokeratin and pan-muscle actin was found in six cases (25%). There was no correlation between cytokeratin and HHF-35 expression. α-Smooth muscle actins were found in four cases and desmin in one but sarcomeric actin was not detected in any tumor. Immunoreactivity patterns did not correlate with the cytologic appearance of the mesenchymal proliferation or the biphasic patterns of growth. We conclude that smooth muscle actins can be expressed in the spindle cells of SpCCa and that this myogenic profile is likely a manifestation of myofibroblastic or smooth muscle differentiation rather than rhabdomyosarcomatous or myoepithelial differentiation given the light and electron microscopic findings. The expression of vimentin and muscle actins may lead to an erroneous diagnosis of myosarcoma or malignant fibrous histiocytoma in a small biopsy and, therefore, histologic identification of carcinomatous elements is necessary for the diagnosis of SpCCa of the upper aerodigestive tract.

ISSN:1062-3345    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

We examined four melanotic neuroectodermal tumors (three jaw, one epididymis) of infancy (MNTI) by the immunoperoxidase method for intermediate filament-, neuroendocrine-, and melanoma-associated antigen profiles comparing these immunoreactions with those of 10 pediatric neuroblastomas, five retinoblastomas, and five retinas. Three MNTIs had larger pigmented epithelioid cells and small neuroblastic cells; one was composed mainly of pigmented epithelioid cells. One or more melanoma-associated antigens (HMB-45, HMB-50) and cytokeratin were consistently expressed in the large cells (four of four). The small cells stained for neuron-specific enolase (two of three) and synaptophysin (two of three). Neurofilament- and microtubular-associated proteins were demonstrated in the frozen tissue of one tumor. Both cell types were positive for vimentin, while negative for chromogranin A and S-100. Variable numbers of cells expressed desmin in one case, and muscle-specific actin in two cases. In contrast, neuroblastoma and retinoblastomas stained variably for vimentin, neuron-specific enolase, synaptophysin, and chromogranin. Neither tumor contained melanoma-associated antigens or cytokeratin. Pigment epithelium of the retina coexpressed cytokeratin and melanoma-associated antigens but lacked S-100. The results show that MNTI is a distinctive primitive neoplasm with a polyphenotypic profile of epithelial, neuroblastic, melanin-producing, and mesenchymal differentiation. Melanocytic differentiation in MNTI is distinguished from melanoma by lack of S-100 protein with consistent expression of cytokeratin. Myogenic differentiation in MNTI is a potential source of confusion with rhabdomyosarcomas, especially in small biopsy specimens. Coexpression of cytokeratin and melanoma-associated antigens by pigment-containing cells is similar to that of retinal pigment epithelium.

ISSN:1062-3345    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Microwave irradiation of tissue sections in a solution containing lead salt has been reported to enhance immunohistochemical staining of formalin-fixed, paraffin-embedded materials. To compare the effectiveness of this procedure with protease digestion, which is widely used for the same purpose, we tested 50 pairs of tissue samples, one group fixed overnight and the other intentionally overfixed for 5 days in 10% formalin. The tissue sections were stained with 17 diagnostically useful monoclonal and polyclonal antibodies using the avidin-biotin immunohistochemical method as follows: (a) no special treatment, (b) digestion with 0.1% pronase for 5 min, (c) digestion with 0.1% trypsin for 10 min, and (d) microwave irradiation of sections in the commercially available lead thiocyanate solution as recommended by the manufacturer. Both pronase and trypsin treatment showed improvement of staining of five of the antibodies used. The microwave/metal solution procedure improved the staining with two antibodies (vimentin and glial fibrillary acidic protein), worsened the staining of another four antibodies, and did not modify the remainder. However, staining for glial fibrillary acidic protein was similarly improved by protease digestion. Our results fail to confirm the reported superiority of antigen retrieval by microwave heating in lead salt solutions over protease digestion. Moreover, the microwave/lead salt method has the added disadvantage that it increases laboratory hazards and requires special equipment.

ISSN:1062-3345    

出版商:OVID    

年代:1993

数据来源: OVID