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At least 19 recordsLinked to original sources
PubMed1990

Recovery of nuclei from glycol-methacrylate-embedded tissue.

The analysis of antigens, enzyme histochemical markers, and DNA has become an important part of the classification of some leukemias, lymphomas, and other neoplastic diseases. Many of the relevant antigens and most of the relevant enzyme histochemical activities are destroyed and others are less than optimally preserved in tissues embedded in hot paraffin. Most enzymatic activities and antigens are well preserved in tissues embedded at 4 degrees C in glycol methacrylate (GMA). The measurement of DNA content in neoplastic cells with the most commonly employed techniques depended on the availability of fresh suspensions of cells until the development by Hedley of methods that permit the recovery of nuclei from paraffin blocks for this purpose. In order to facilitate the analysis of antigens, enzymatic markers, and DNA from the same sample of tissue, we have developed a means of recovery of nuclei from GMA-embedded tissues. Twenty-microns-thick sections of GMA-embedded tonsil were either pretreated with an organic solvent (absolute ethanol or 2-ethoxyethanol) followed by rehydration in phosphate buffered saline (PBS) or directly rehydrated in PBS. The suspensions were formed mechanically by gentle sonication. The type of fixative and length of PBS rehydration were varied. Tissue fixed in 100% acetone, embedded in GMA, and rehydrated directly in PBS for six days gave the highest average yield of nuclei, 3.7 x 10(7) nuclei per gram tissue. In order to assess DNA binding of fluorescent dyes, 2-microns-thick GMA sections were stained with chromomycin, Hoechst 33342 (Sigma Chemical, St Louis, MO), and propidium iodide. Hoechst 33342 bound specifically to the nuclei with low background staining.

Benzimidazoles↗
PubMed1992

Simultaneous assessment of TGFB and cell cycle kinetics using IUdR/BrdU infusions in human neoplasms from plastic-embedded tissue.

We describe an immunohistochemical technique that makes use of two monoclonal antibodies (MAb), one to detect the transforming growth factor B (TGFB) and another that reacts with iodo- and bromodeoxyuridine. The purpose of this technique is to determine the relationship between TGFB expression and the S-phase cells in human tumors. Since both can be distinctly identified in situ from tissue embedded in plastic, in assessment of the geographic orientation of S-phase cells in relation to such factors as TGFB, contiguity to blood vessels, nerve fibers, and macrophages can also be achieved.

Antibodies, Monoclonal↗
PubMed1990

Haemopoiesis in human fetal and embryonic liver. Immunohistochemical determination in B5-fixed paraffin-embedded tissues.

Paraffin embedded tissue reactive monoclonal antibodies were used to study human embryonal and fetal haemopoiesis, combining optimal morphology with immunohistological determination of haemopoietic cell subtypes and their microenvironment. Seven embryonal and twelve fetal liver specimens were studied, having been fixed in B5-fixative and embedded in paraffin. The different haemopoietic lineages each showed their own immunophenotype and distribution; intercellular and microenvironmental relationships were easily determined. Erythroid cells are reactive with VIE-G4, LN1, and MT1, sometimes partly surrounding a central macrophage. Myelomonocytic cells react with LCA, MT1, MB3, LN2, and anti-lysozyme, and from 14 weeks onwards with LN3. Lymphoid cells show LCA, MT1, MT2, MB1, MB2, MB3, and LN2 reactivity. In a few cases some scarce My10+ early progenitor cells were seen. An important finding is the extensive MT1-reactivity distributed over all haemopoietic lineages, and the demonstration of immature haemopoietic blast cells exclusively expressing the MT1 antigen. Further studies employing MT1 are necessary to delineate the extent of the distribution and the possible function of the antigen. Use of the MT1 mAb may contribute to the elucidation of the exact nature of the haemopoietic blast cells and their place in haemopoietic development.

Antibodies, Monoclonal↗
PubMed1991

A comparison of the atomic composition of siderosomes (haemosiderin) in cryosections of unfixed frozen tissues and Epon-embedded tissues.

Siderosomes (i.e. single membrane-bound lysosomal bodies containing haemosiderin) were produced in the liver and muscle of rats by injections of iron dextran. Electron-probe X-ray analysis was executed on siderosomes in cryosections of quick-frozen fresh unfixed tissues (liver and muscle) and sections of Epon-embedded tissues. There were no statistically significant differences between the ratios of iron:phosphorus and iron:sulphur in these two types of preparations. Hence it is concluded that there is no significant loss or gain of phosphorus or sulphur during preparation of tissues for Epon embedding. The results confirm past belief that so little phosphorus or sulphur is present in siderosomes that haemosiderin is best regarded as ferric hydroxide oxide. A new finding in the present study was the demonstration of small amounts of potassium in siderosomes in cryosections. It seems that potassium is lost (leaches out) from siderosomes during preparation of tissues for Epon-embedding.

Animals↗
PubMed1985

Immuno gold staining (IGS) for electron microscopical demonstration of glial fibrillary acidic (GFA) protein in LR white embedded tissue.

Post-embedding immunocytochemical staining methods using gold have so far failed to label intermediate filament antigens in situ in epon or araldite embedded tissue. We have now applied the post-embedding immuno gold staining (IGS) technique for LR White embedded tissue. Glial fibrillary acidic (GFA) protein immunoreactivity was clearly demonstrated electron microscopically on astrocytic filaments of rat cerebellum in situ.

Animals↗
PubMed1989

A modified Brown and Hopps stain for identification of gram-positive and gram-negative microorganisms in glycol methacrylate-embedded tissues.

Plastic embedding is a recently developed technique that has been shown to be superior to conventional paraffin embedding in the histopathologic identification of microorganisms in tissue specimens. This report describes a modification of the Brown and Hopps stain for the differentiation of gram-positive and gram-negative microorganisms in 3-micron-thick plastic sections. This technique is easily performed and has a rapid turnaround time. This staining method permits a more precise histopathologic diagnosis of infectious agents than is possible in paraffin-embedded tissues.

Acrylates↗
PubMed1991

A monoclonal antibody to human leukocyte common antigen, SHL-1, and its use for formalin-fixed, paraffin-embedded tissues.

The authors describe a newly characterized murine monoclonal antibody to the human leukocyte surface antigen, SHL-1. The antigen belongs to the leukocyte common antigen (LCA) family, and its molecular weight is about 180,000 daltons, which is similar to that of some previously characterized LCAs. The SHL-1 antigen is resistant to conventional tissue-fixation and embedding procedures. This antibody can therefore be used in the immunohistochemical staining of paraffin-embedded tissue sections. Wide screening with a sufficient number of both fresh and routinely processed paraffin-embedded tissues was done with indirect immunoperoxidase technique. With this procedure, SHL-1 labeled the majority of normal leukocytes and hematopoietic malignancies. Some B-cell malignancies were not stained with this antibody. The non-hematologic malignancies posing diagnostic problems of differentiation from lymphomas or leukemias were completely negative to SHL-1. The immunoreactivity to SHL-1 of samples from 24 leukemic patients and 15 human tumor cell lines was determined by the immunofluorescence method. Of 24 leukemic preparations, 23 were strongly reactive to this antibody. One case of B-cell leukemia did not react with SHL-1. No immunoreactivity was demonstrated in non-hematopoietic tumor cell lines. The overall reaction pattern of SHL-1 proved its usefulness in both diagnostic and research practice in hematological disorders. This antibody detected cell surface antigens of the T cell series more effectively than those of the B-cell series in terms of the positive number of cells and mean fluorescence intensity.

Antibodies, Monoclonal↗
PubMed1987

The formaldehyde-fixed and paraffin-embedded tissues for diagnostic transmission electron microscopy: a retrospective and prospective study.

The fine structures of tissues processed routinely for light microscopy were studied retrospectively in 44 tissues and tumors and prospectively in 13 tissues and tumors. In the prospective study, we fixed tissues in an ample amount of fixatives, carefully avoiding crushed and air-dried portions, and processed them by five methods. The fine structures of the retrospective cases were mostly poor or passable, whereas those of the prospective cases were generally good. All formaldehyde-fixed tissues showed varied degrees of tissue extraction, notably of lipids, membranous structures, ribosomes, glycogen, and other loose cellular and intercellular matrix materials, that was related to the status and type of tissue as well as the kind and duration of fixation, dehydration, and tissue clearance. Paraffin embedding per se appeared to cause little alteration of the fine structure. Transmission electron microscopy of the paraffin-embedded tissue appeared most useful to identify infective agents, foreign particles, and densely packed organelles or structures, usually in the differential diagnosis of neoplasms. Although many factors are difficult to control, initial careful thin slicing, judicious selection, and fixation of the tissue (even by regular phosphate-buffered formaldehyde solution) can improve the fine structure of paraffin-embedded tissues and be useful in the direct correlation of light and electron microscopic findings.

Bone Marrow Diseases↗
PubMed1986

Ia antigens in plastic-embedded tissues: a post-embedding immunohistochemical study.

The aim of the present study was to establish a plastic embedding technique that makes possible the immunohistochemical demonstration of class II major histocompatibility complex (MHC) antigens (Ia antigens) in undecalcified joint tissues. Therefore a series of fixatives and dehydrating agents was tested for saving Ia immunoreactivity by post-embedding immunostaining of thin sections (2 microns) of rat tissues that had been embedded in glycol methacrylate (GMA), and by comparing with cryostat sections. An indirect immunoperoxidase and the avidin-biotin complex (ABC) technique were used. Combined with fixation by 4% formaldehyde, dehydration with GMA was found to give the best preservation of Ia antigenicity, followed by dehydration with ethylene glycol. The thinness of tissue sections facilitated the association of Ia antigens with different subcellular compartments in distinct cell populations. These various patterns are described.

Animals↗
PubMed1989

Measurement of S-phase fractions in lymphoid tissue comparing fresh versus paraffin-embedded tissue and 4',6'-diamidino-2 phenylindole dihydrochloride versus propidium iodide staining.

S-phase fractions for 62 lymphoid biopsies were calculated, by means of flow cytometry, from both fresh and paraffin-embedded tissue. The purposes of this study were to determine whether significant differences were seen between S-phase estimates obtained from fresh and fixed tissue and to compare results obtained with two DNA dyes, namely 4'-6'-diamidino-2 phenylindole dihydrochloride (DAPI) and propidium iodide (PI). The 62 cases consisted of 38 cases of non-Hodgkin's lymphoma (NHL), 19 reactive samples, and 5 cases of Hodgkin's disease. Fifty-four of the samples showed DNA diploid profiles. A good agreement between S-phase results from fresh and fixed tissue was seen, with technical factors accounting for around 20% of the total variance. Using a paired t test, no significant difference was seen between fresh and fixed tissue for diploid cases, but there was a trend for S-phase estimates from fixed tissue to be higher. If all cases (including the eight DNA aneuploid samples) were included in the analysis this difference just reached statistical significance (P less than .05). In a subgroup of 19 of the cases, a comparison was performed on both fresh and fixed tissue of staining with DAPI and PI. A good agreement between results with both DNA stains was found on fresh and fixed tissue, with no significant differences being apparent, and stain-related factors accounted for only 10% of the total variance.

Cell Cycle↗
PubMed1992

p53 overexpression in formalin-fixed, paraffin-embedded tissue detected by immunohistochemistry.

Mutation and overexpression of the p53 gene have been noted in a wide range of human cancers and are thought to play a role in malignant transformation. Previously, immunohistochemical detection of p53 has been possible only in fresh-frozen tissues. We examined p53 expression in paraffin-embedded tissues from 50 epithelial ovarian cancers and 25 primary breast cancers with a modified immunohistochemical (IHC) technique developed in this laboratory, using monoclonal antibody (MAb) PAb1801. The 75 cases were selected from a group of patients in whom the expression levels had already been assessed in a fresh-tissue IHC assay. An identical staining reactivity was observed in both formalin-fixed, paraffin-embedded tissue and fresh-frozen tissue in 48 of 50 (96%) epithelial ovarian cancers and in 23 of 25 (92%) primary breast cancers. Immunodetection of p53 in paraffin-embedded tissue blocks will be a useful alternative to the standard fresh-tissue assay and can accurately reflect the level of p53 expression in human tumors.

Antibodies, Monoclonal↗
PubMed1987

Utilization of monoclonal antibody L26 in the identification and confirmation of B-cell lymphomas. A sensitive and specific marker applicable to formalin-and B5-fixed, paraffin-embedded tissues.

Immunophenotypic analysis of paraffin-embedded tissues of lymphoproliferative disorders has been facilitated by recent developments of monoclonal antibodies that react with epitopes that survive histologic processing. Leukocyte common antigen (LCA) antibody has made a significant contribution to the immunocytochemical separation of non-Hodgkin's lymphomas from nonlymphoid neoplasms. However, a small percentage of lymphomas, particularly some large cell or immunoblastic B-cell tumors, will not label with LCA antibody. Other antibodies, directed against B lymphocytes, experience problems of specificity and a lack of sensitivity when applied to formalin-fixed specimens. The authors recently investigated a monoclonal antibody (L26) that demonstrates excellent specificity and sensitivity for B lymphocytes, and tumors derived from them, in formalin- and B5-fixed, paraffin-embedded tissue. The avidin-biotin peroxidase complex (ABC) technique was utilized for immunostaining 95 cases of malignant lymphoproliferative disorders and a variety of normal and neoplastic nonlymphoid tissues. When applied to sections of benign lymphoid tissue, the L26 antibody labeled germinal center cells, mantle zone and scattered interfollicular lymphocytes, but not histiocytes or plasma cells. L26 marked 100% (44/44) of the large cell and immunoblastic B-cell lymphomas, along with 1 case of pre-B cell lymphoblastic lymphoma. This included 8 cases that were LCA-negative. None of the T-cell lymphomas or plasma cell tumors studied demonstrated L26 immunostaining. No normal, benign, or neoplastic nonlymphoid tissues examined stained with this antibody. L26 successfully labels B lymphocytes and B-cell lymphomas in routinely processed tissues, often with greater sensitivity and intensity than LCA. This antibody should prove invaluable in the investigation of atypical lymphoid proliferations and the identification of B-cell derived lymphomas, when fresh or frozen tissue is unavailable for analysis.

Antibodies, Monoclonal↗
PubMed1987

Monoclonal antibody L26: an antibody that is reactive with normal and neoplastic B lymphocytes in routinely fixed and paraffin wax embedded tissues.

Formalin fixed and paraffin wax embedded tissue from 85 well characterised cases of non-Hodgkin's lymphoma and Hodgkin's disease were studied using the avidin-biotin-peroxidase complex technique. Among the non-Hodgkin's lymphomas all cases of B cell lymphoma were reactive with L26, a monoclonal antibody which is as yet an unclustered pan B cell reagent, with the exception of pre-B cell acute lymphoblastic leukaemia and malignant lymphoma plasmacytic. Eighteen well characterised cases of T cell lymphoma, selected to include tumours previously shown to exhibit cross reactivity with antibodies to fixation resistant B cell related antigens, were similarly studied. Neoplastic cells in all but one case were unstained by L26. Twenty seven cases of Hodgkin's disease were also examined. In five cases all Reed-Sternberg cells and their variants were strongly stained by L26; only a proportion of Reed-Sternberg cells and their variants were recognised in a further five cases. Monoclonal antibody L26 promises to be a valuable reagent for the diagnosis of malignant lymphoma in routinely fixed and paraffin wax embedded tissues. Its advantage lies in its sensitivity and greater B cell specificity than any of the B cell related reagents currently available for the study of malignant lymphoma in fixed tissues.

Antibodies, Monoclonal↗
PubMed1986

An immunocytochemical study of T-cell lymphomas using monoclonal and polyclonal antibodies effective in routinely fixed wax embedded tissues.

Formalin fixed and paraffin wax embedded tissue from 24 cases of T-cell lymphoma diagnosed using immunocytochemistry on cryostat sections was examined using a panel of eight monoclonal and three polyclonal antisera. The monoclonal antibodies UCHL1 and MT1 proved to be comparable and reliable markers of neoplastic cells in T-cell lymphomas. The B-cell specific marker, MB1, strongly stained all cells in two cases of pleomorphic large cell T-cell lymphoma, large cells in two cases of pleomorphic mixed medium and large cell lymphoma, and isolated clusters of blast cells in four cases of T-zone and angioimmunoblastic lymphadenopathy-like T-cell lymphoma. The cells stained by MB1 expressed T suppressor/cytotoxic surface markers on frozen section. Epithelial membrane antigen, as detected by a polyclonal anti-EMA and the monoclonal antibody HMFG2, was expressed in 36% of tumours especially those of monomorphic large cell and pleomorphic large cell phenotype. Single granules or finely dispersed cytoplasmic granularity was seen in four tumours using the anti-granulocyte reagent Leu M1. Tumour cells in one case stained in a pattern identical to Reed-Sternberg cells in Hodgkin's disease. Granular alpha-1-antitrypsin staining was found in 10 cases of pleomorphic large cell and monomorphic large cell lymphoma. No staining was observed using anti-lysozyme or the monoclonal macrophage specific marker Mac411. Monomorphic and pleomorphic large cell lymphomas tended to show a common immunophenotype with the majority of cells co-expressing alpha-1-antitrypsin HLA-DR and epithelial membrane antigen. Scattered large transformed blast cells in cases of angioimmunoblastic lymphadenopathy-like T-cell lymphomas and T-zone lymphomas shared a similar immunophenotype with the large cell lymphomas. Using a panel of monoclonal antibodies effective in paraffin embedded tissue, diagnostically useful staining profiles which correlate with the morphological phenotype can be established in T-cell lymphomas.

Antibodies, Monoclonal↗
PubMed1992

Molecular pathology of paraffin-embedded tissue. Current clinical applications.

Molecular biology techniques have been adapted to analyze paraffin-embedded tissues, expanding their potential clinical utility. The isolation of intact nucleic acids from tissue blocks is fundamental to the molecular pathology of paraffin-embedded tissues. In vitro amplification with the polymerase chain reaction (PCR) promises to be the most useful means of retrospective analysis since it can be performed successfully on DNA that has partially degraded during fixation, paraffin embedding, and the extraction process. Four clinical situations in which DNA analysis of paraffin-embedded tissues can be helpful are: (a) gene rearrangement analysis in lymphoproliferative disorders, where fresh tissue has not been obtained at the time of surgery; (b) identification of infectious agents, particularly viruses; (c) genetic testing of families with a putative inherited disease where the affected member has died; and (d) specimen identification. The PCR and other techniques of genetic analysis are powerful in sensitivity and specificity when performed and interpreted with appropriate precautions and controls. DNA analysis of paraffin-embedded tissues will likely become a fixed part of the future pathologist's diagnostic armamentarium.

DNA↗