Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Tissue Embedding”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources
PubMed2002

Immunohistochemical detection of immunoglobulin light chain expression in B-cell non-Hodgkin lymphomas using formalin-fixed, paraffin-embedded tissues and a heat-induced epitope retrieval technique.

Definitive diagnosis of B-cell non-Hodgkin lymphomas often requires demonstration of B-cell monoclonality. Immunohistochemical detection of monotypic immunoglobulin light chain expression, and thereby B-cell monoclonality, may be accomplished readily using fresh cell suspensions or frozen tissue sections. However, immunohistochemical detection of immunoglobulin light chain expression in formalin-fixed, paraffin-embedded tissues is more difficult; with few exceptions, techniques suitable for formalin-fixed, paraffin-embedded tissues are not widely available. This report describes and validates a method for detecting immunoglobulin light chain expression in formalin-fixed, paraffin-embedded tissues using a heat-induced epitope retrieval technique. This method was evaluated in a series of 113 cases of B-cell non-Hodgkin lymphoma, including 73 cases with correlative flow cytometric immunophenotyping data. Monotypic light chain expression was demonstrated in 91 (81%) of 113 cases, including several small core biopsy specimens with extremely limited tissue. Compared with the reference method (flow cytometric immunophenotyping), the specificity of the assay was 100%. Interobserver reproducibility was excellent, with 87% concordance between two independent observers categorizing cases as indeterminate, suggestive or diagnostic of kappa or lambda light chain restriction (Cohen kappa statistic: 0.81). In summary, the described method permits demonstration of immunoglobulin light chain expression in formalin-fixed, paraffin-embedded tissues in approximately 80% of cases of B-cell non-Hodgkin lymphoma with a high degree of specificity and excellent interobserver reproducibility. The assay is sufficiently robust for diagnostic use in small biopsies in which fresh tissue is unavailable.

Epitopes↗
PubMed2000

[Methods for microdissection-PCR-silver stain technique in paraffin-embedded tissue sections].

OBJECTIVE: To use the microdissection-PCR-silver stain technique in the paraffin- embedded tissue sections and analyze the microsatellite instability in colorectal cancer. METHODS: By microdissection technique, the lymphocytes and mesenchymal cells, normal mucous epithelial cells, displasia, adenoma, and carcinoma cells were recovered from paraffin-embedded tissue sections. The cells were digested by protinase K; the cell lysates were used as PCR template and the PCR products were analysed by denatured polyacrylamide gel electrophoresis and silver stain. Four microsatellite loci, TGF-betaRII(A)(10), hMSH(2)(A)(26)-Bat-26, hMSH(3)(A)(8), hMSH(6)(C)(8), were analyzed. RESULTS: In all 28 specimens, hMSH(3)(A)(8) and hMSH(6)(C) 8) loci were amplified successfully. TGF-betaRII(A)10), Bat-26 had consistent amplification in 23/28, 22/28 specimens, respectively. And Bat-26 microsatellite instability was found in carcinoma cells in 5 specimens, and in adenoma cells in one of the 5 specimens. CONCLUSION: Microdissection-PCR silver stain technique can be used in paraffin-embedded tissue sections with satisfactory results. This method can be employed in analyzing microsatellite instability in colorectal carcinoma.

Colorectal Neoplasms↗
PubMed1997

Analysis of T cell receptor beta chain CDR3 size using RNA extracted from formalin fixed paraffin wax embedded tissue.

AIMS: To isolate RNA and DNA simultaneously from formalin fixed paraffin wax embedded tissue to assess the clonality of enteropathy associated T cell lymphomas and to analyse it in detail by a non-radioactive method of T cell receptor complementarity determining region 3 (CDR3) spectratyping. METHODS: DNA and RNA were isolated simultaneously from formalin fixed paraffin wax embedded tissue blocks and subjected to the polymerase chain reaction (PCR) and semi-nested reverse transcription PCR (RT-PCR), respectively. The RT-PCR T cell receptor V beta products were analysed by CDR3 spectratyping using a denaturing polyacrylamide gel and silver staining. RESULTS: Usable DNA and RNA were isolated simultaneously from formalin fixed paraffin wax embedded tissue. The specific clonality of the tissue was successfully analysed by a non-radioactive method of T cell receptor CDR3 spectratyping of the RT-PCR products. CDR3 spectratying of the RT-PCR products demonstrated the precise clonal nature of the tumour and non-tumour tissue showing that the non-tumour tissue comprised an oligoclonal population of a number of different T cell receptor V beta families. The tumour tissue comprised two T cell subtypes of the one family, T cell receptor V beta 9. CONCLUSIONS: RNA and DNA were isolated from formalin fixed paraffin wax embedded enteropathy associated T cell lymphoma tissue. Detailed analysis of clonality can be carried out by a non-radioactive method of CDR3 spectratyping.

DNA, Neoplasm↗
PubMed1997

[A simple and rapid method of preparing cell or tissue embedded in situ for transmission electron microscopy].

A simple and rapid method of preparing cell or tissue embedded in situ for transmission electron microscopy (TEM) is recommended. It is very simple; all procedures, including fixation, dehydration, infiltration and embedding, are performed on the same carrier (culture vase or microscope slides). It is also very rapid; the whole process takes only five hours. The entire cell or tissue embedded in situ is easily separated from the carrier. The ultrastructures of the cell or tissue embedded in situ are well preserved with minimal damage. This method can be used in preparing cultured monolayer cell for TEM study, paraffin section for electron microscopic diagnosis, and frozen section for TEM immunohistochemistry or enzymehistochemistry. The main points of the procedures of preparation have been discussed.

Humans↗
PubMed2006

Transfer and multiplex immunoblotting of a paraffin embedded tissue.

As we transition from genomics to the challenges of the functional proteome, new tools to explore the expression of proteins within tissue are essential. We have developed a method of transferring proteins from a formalin fixed, paraffin embedded tissues section to a stack of membranes which is then probed with antibodies for detection of individual epitopes. This method converts a traditional tissue section into a multiplex platform for expression profiling. A single tissue section can be transferred to up to ten membranes, each of which is probed with different antibodies, and detected with fluorescent secondary antibodies, and quantified by a microarray scanner. Total protein can be determined on each membrane, hence each antibody has its own normalization. This method works with phospho-specific antibodies as well as antibodies that do not readily work well with paraffin embedded tissue. This novel technique enables archival paraffin embedded tissue to be molecularly profiled in a rapid and quantifiable manner, and reduces the tissue microarray to a form of protein array. This method is a new tool for exploration of the vast archive of formalin fixed, paraffin embedded tissue, as well as a tool for translational medicine.

Antibodies, Phospho-Specific↗
PubMed2005

Methodology for preservation of high molecular-weight RNA in paraffin-embedded tissue: application for laser-capture microdissection.

Laser-capture microdissection techniques have enhanced the ability to perform molecular studies of pure-cell populations. Although many technical factors affect the outcome of the procedure, none is more critical than the appropriate handling of the tissue. Because extraction of intact RNA from paraffin-embedded tissue is a difficult and inconsistent process, frozen sections with their attendant problems are used for this purpose. The major limitation of frozen section is its inferior morphologic quality compared with paraffin-embedded sections that may complicate accurate identification of cells during microdissection. We have developed a procedure that provides both high-quality histomorphology and RNA preservation in paraffin-embedded tissue. It is based on the use of a methanol-based fixative coupled with microwave-assisted rapid tissue processing. This technology in conjunction with a modified hematoxylin-eosin stain and a RNA extraction method allows isolation of high molecular-weight RNA from laser-capture microdissected, hematoxylin and eosin-stained paraffin sections. The high quality of the extracted RNA was confirmed by capillary electrophoresis and RT-PCR. The combination of a methanol-based fixative, rapid microwave tissue processing, and a modified hematoxylin and eosin stain produces paraffin sections that yield high molecular-weight RNA upon microdissection. This methodology opens the door for a wide range of gene expression analyses using paraffin-embedded tissue.

Electrophoresis, Capillary↗
PubMed2002

DNA extraction from archival formalin-fixed, paraffin-embedded tissue sections based on the antigen retrieval principle: heating under the influence of pH.

During the course of diagnostic surgical pathology, pathologists have established a large collection of formalin-fixed, paraffin-embedded tissues that form invaluable resources for translational studies of cancer and a variety of other diseases. Accessibility of macromolecules in the fixed tissue specimens is a critical issue as exemplified by heat-induced antigen retrieval (AR) immunohistochemical (IHC) staining. On the basis of observations that heating may also enhance in situ hybridization (ISH) and the similarity of formalin-induced chemical modifications that occur in protein and in DNA, we designed a study to examine the efficiency of DNA extraction from archival formalin-fixed, paraffin-embedded tissues using an adaptation of the basic principles of the AR technique, i.e., heating the tissue under the influence of different pH values. Archival paraffin blocks of lymph nodes, tonsil, and colon were randomly selected. Each paraffin block was prepared in 34 microtubes. For each paraffin block, one tube was used as a control sample, using a non-heating DNA extraction protocol. The other 33 tubes were tested using a heating protocol under 11 variable pH values (pH 2 to 12) under three different heating conditions (80, 100, and 120C). Evaluation of the results of DNA extraction was carried out by measuring yields by photometry and PCR amplification, as well as kinetic thermocycling (KTC)-PCR methods. In general, lower pH (acid) solutions gave inferior results to solutions at higher pH (alkaline). Heating tissues at a higher temperature and at pH 6-9 gave higher yields of DNA. There appeared to be a peak in terms of highest efficiency of extracted DNA at around pH 9. The average ratios 260:280 of extracted DNA also showed better values for samples heated at 120C. PCR products of three primers showed satisfactory results for DNA extracted from archival paraffin-embedded tissues by heating protocols at pH 6-12, with results that were comparable to the control sample subjected to the standard non-heating, enzymatic DNA extraction method. This study is the first to document the use of heating at an alkaline pH for DNA extraction from archival formalin-fixed, paraffin-embedded tissues, a recommendation based on the principles of AR for protein IHC. These findings may lead to a more effective protocol for DNA extraction from archival paraffin-embedded tissues and may also provide enhanced understanding of changes that occur during formalin-induced modification of nucleic acids.

Antigens↗
PubMed1992

Rapid detection and species identification of mycobacteria in paraffin-embedded tissues by polymerase chain reaction.

The sensitivity and specificity of the polymerase chain reaction (PCR) in the detection of mycobacteria in paraffin-embedded tissues and in crude lysates of mycobacterial cultures were assessed. Sections of formalin-fixed, paraffin-embedded tissues were deparaffinized and then subjected to a simple proteinase K and boiling lysis procedure. These preparations were used directly for PCR amplification of the 383 bp segment of the gene encoding the 65 kDa mycobacterial surface antigen. Crude lysates of mycobacteria were used as positive controls. The specificity of the PCR products was confirmed by Southern blot using a region-specific digoxigenin-labeled oligonucleotide probe and chemiluminescent detection. The 383 bp diagnostic fragment was visualized in 11 of 12 acid-fast bacilli (AFB) stain/culture-proven-positive blocks. Crude lysates of mycobacteria were detected to a sensitivity of approximately 80 organisms. Amplified fragments from paraffin-embedded tissues and mycobacterial cultures of M. tuberculosis, M. avium-intracellulare, and saprophytic mycobacteria were distinguished by digestion with Nar 1 restriction endonuclease. These results suggest that PCR amplification followed by restriction enzyme digestion of the PCR product is a rapid, specific, and highly sensitive technique for the detection and speciation of mycobacteria in paraffin-embedded tissues.

Base Sequence↗
PubMed1992

Variation in reference cells for DNA analysis of paraffin-embedded tissue.

Selection of the diploid reference cells used in flow cytometric DNA analysis of paraffin-embedded tissue is inconsistent in the literature. To determine which types of cells were most suitable for use as reference cells, benign paraffin-embedded tissue was evaluated from nine randomly selected autopsies. Benign kidney, lymph node, gastrointestinal mucosa, laryngeal mucosa, bronchial mucosa, bladder mucosa, pancreas, and, when available, prostate tissue were studied. Ten paraffin-embedded surgical specimens also were studied. In the autopsy specimens, great variability in the mean peak channels was noted on intrapatient evaluation and even more variability was present when comparing similar organs (especially lymph nodes) from different patients. Similar results were obtained using lymph nodes from surgical specimens. It is concluded that the most suitable diploid reference cells for DNA analysis of paraffin-embedded tissue are the benign cells present in the paraffin tumor block that have been processed in the same way as the tumor cells.

Aged↗
PubMed1984

[Immunologic diagnosis of cutaneous lymphomas. I. A new immunoperoxidase technic for the demonstration of cell- and tissue-bound antigens in formalin-fixed paraffin-embedded tissues using protein A-peroxidase as a universal second antibody for mono- and polyclonal antibodies].

Immunoperoxidase techniques, applied to formalin-fixed paraffin embedded tissues, provide a simultaneous histopathological and immunological diagnosis. Application of protein-A-peroxidase constitutes a new technical variant: The technique is relatively simple, decreases non-specific background staining, and binds mono- and polyclonal antibodies from different mammalian species.

B-Lymphocytes↗
PubMed1988

The immunophenotyping of extramedullary myeloid cell tumors in paraffin-embedded tissue sections.

Extramedullary tissue infiltrates of acute myeloid leukemia are rare and often difficult to recognize in routine paraffin-embedded tissue sections. Since appropriate therapy for these tumors depends on their precise identification, we have studied a series of tissues infiltrated with primitive myeloid cells using monoclonal and polyclonal antibodies capable of labeling cells of the myeloid/monocytic system in paraffin-embedded tissue sections. The current retrospective study involved tissues from 15 patients (eight men and seven women) with a mean age of 51 years (range, 23-77). A diagnosis of extramedullary myeloid cell tumors had been made on the basis of routine histology, chloroacetate esterase cytochemical stain, and--in some cases--electron microscopy. Paraffin-embedded tissue sections were cut and stained employing the alkaline phosphatase antialkaline phosphatase (APAAP) immunocytochemical procedure with monoclonal antibodies against leukocyte-common antigen (PD7/26-2B11), restricted components of the leukocyte-common antigen (UCHL1, 4KB5), granulocytes (Mac-387, Leu-M1), leukocytes (MT1, MT2, LN1, LN2), HLA-DR (LN3), and elastase (NP57), as well as polyclonal antibodies against lactoferrin, lysozyme, alpha-1-antitrypsin, and alpha-1-antichymotrypsin. Results indicate that antibodies against Mac-387, elastase, and lysozyme are most useful in the recognition of neoplastic myeloid cells. We conclude that tissues containing granulocytic tumors can be identified in paraffin-embedded tissue sections using a panel of antibodies and the APAAP procedure.

Adult↗
PubMed1988

Dehydrogenase enzyme histochemistry on freeze-dried or fixed resin-embedded tissue.

A method has been developed for the histochemical demonstration of a variety of dehydrogenases in freeze-dried or fixed resin-embedded tissue. Seven dehydrogenases were studied. Lactate dehydrogenase, NADH dehydrogenase and NADPH tetrazolium reductase were all demonstrable in sections of paraformaldehyde-fixed resin-embedded tissue. Freeze-dried specimens were embedded, without fixation, in glycol methacrylate resin or LR Gold resin at either 4 degrees C or -20 degrees C. All the dehydrogenases except succinate dehydrogenase retained their activity in freeze-dried, resin-embedded tissue. Enzyme activity was maximally preserved by embedding the freeze-dried tissue specimens in glycol methacrylate resin at -20 degrees C. The dehydrogenases were accurately localized without any diffusion when the tissue sections were incubated in aqueous media. Addition of a colloid stabilizer to the incubating medium was not required. Freeze-drying combined with low-temperature resin embedding permits accurate enzyme localization without diffusion, maintenance of enzyme activity and excellent tissue morphology.

Animals↗
PubMed1994

Applications of DNA flow cytometry and fluorescence in situ hybridization using a chromosome-specific DNA probe on paraffin-embedded tissue sections of primary malignant melanomas.

We have applied DNA flow cytometric analysis to paraffin-embedded tissue sections of primary malignant melanomas. Conventionally, flow cytometric analysis of paraffin-embedded tissue sections has been done by the method of Hedley et al. We added ultrasound treatment to the method of Hedley et al. and a lower value of coefficient of variation was shown. Furthermore, a new technique, fluorescence in situ hybridization with a chromosome-specific repetitive DNA probe, was used for the analysis of chromosomal numerical aberrations in the same paraffin-embedded tissue sections. The DNA flow cytometric analysis showed that in 8 cases six primary malignant melanomas were of the aneuploid pattern and two cases of lentigo maligna (melanoma in situ) were of the diploid pattern. By fluorescence in situ hybridization, the two cases with the diploid pattern had spots/nucleus of 1.28 and 1.12, and those with the aneuploid pattern had spots/nucleus from 2.01 to 2.27. Only one nodular melanoma in an aneuploid case showed spots/nucleus of 1.71. These data indicate that fluorescence in situ hybridization with chromosome-specific repetitive DNA probes can serve as a cytogenetic tool for the analysis of interphase nuclei of solid human tumors and may be useful for the study of tumor cell heterogeneity.

Adult↗
PubMed1977

Electron spin resonance spectra of chicken liver and hepatoma tissue embedded in paraffin.

ESR spectra of chicken liver and hepatoma tissue embedded in paraffin display signals characteristic of free radicals and paramagnetic complexes. Owing to embedding the spectrum is altered as compared to that of the native tissue but remains characteristic of the respective tissues. The spectra of tissues embedded in paraffin allow no more than qualitative conclusions to be drawn concerning the spectra of the native tissues, even if appropriate controls are applied.

Carcinoma, Hepatocellular↗
PubMed2004

Wild-type estrogen receptor beta expression in normal and neoplastic paraffin-embedded tissues.

Recently, several antibodies have allowed the detection of estrogen receptor beta (ER-beta) in paraffin-embedded tissue; however, these attempts have failed to specifically identify the wild-type form and revealed technical difficulties such as the necessity for alterations to standard staining protocols and amplification detection systems. The aim of this study was to generate a monoclonal antibody that could provide enhanced sensitivity for detection of ER-beta in paraffin embedded tissues. A 130-amino acid region of the C-terminus of ER-beta was expressed as a fusion protein and used as an antigen to generate monoclonal antibodies. Immunohistochemical analysis of ER-beta using clone EMR02 in normal and inflamed tissues demonstrated nuclear staining. In benign and malignant tumors, variable intensities of staining and patterns of nuclear reactivity were observed between cases. Intense ER-beta positivity was also observed in tumor-infiltrating lymphocytes. Mapping studies by ELISA and Western blotting have identified specific reactivity of EMR02 to a 17-amino acid sequence of the full-length wild-type ER-beta protein (ERbetawt). Our results show that clone EMR02 is a sensitive tool for the detection of ERbetawt in paraffin-embedded tissues. This preliminary study also supports its use in immunohistochemical studies to determine the role of ERbetawt as a tumor prognostic marker and a possible therapeutic target.

Animals↗
PubMed1990

Immunohistochemical detection of c-myc oncoprotein in paraffin embedded tissues.

In almost all studies using paraffin embedded tissue, c-myc protein has been found in the cytoplasm of cells. Since the protein is normally localized in the nucleus it is difficult to determine which histochemical observations are real and which are artefactual. The study designed here evaluated several different methods of fixation prior to paraffin embedding in an attempt to identify which would prevent the diffuse of the protein out of the nucleus. Using various fixation procedures (formalin, paraformaldehyde, B-5, Zamboni and AMeX) we found that fixation in cold acetone (-20 degrees C) overnight followed by 2x15 min fixation in acetone at +4 degrees c and at room temperature, cleared in methyl benzoate and xylene (AMeX procedure) gives reproducible nuclear staining when a variety of normal and tumor tissues are treated with an anti c-myc protein antibody. This method was then compared to frozen sections. While there was no cytoplasmic staining in same tissue specimens in both AMeX processed and frozen sections, the tissue architecture was much better preserved in AMeX processed samples. Our data strongly suggest that AMeX fixation, originally developed for T and B lymphocyte antigens, should be used for immunolocalization of c-myc oncoprotein in paraffin embedded tissues.

Cell Nucleus↗
PubMed2000

Methacarn fixation: a novel tool for analysis of gene expressions in paraffin-embedded tissue specimens.

To establish a quantitative method for analysis of gene expressions in small areas of tissue after paraffin embedding, preliminary validation experiments with RT-PCR and Western blotting were performed using methacarn-fixed rodent tissues and a cultured PC12 cell line. A total RNA yield of 52 +/- 15 ng/mm2, sufficient for a quantitative RT-PCR of many genes, could be extracted from a deparaffinized 10-microm-thick rat-liver section by a simple, single-step extraction method. The low concentration of contaminating genomic DNA and the resolution of ribosomal RNAs in RNA gel proved the purity and integrity of the extracted RNA samples, allowing PCR amplification of a long mRNA sequence and mRNA species expressing low copy numbers. PCR amplification of mRNA-derived target gene fragments could be achieved by optimizing the amount of total RNA for reverse transcription and the number of subsequent PCR cycles for each gene. By this validation, organ- and sex-specific mRNA expression could be detected in methacarn-fixed paraffin-embedded tissues without additional DNase treatment of RNA samples. RT-PCR analysis could also be performed with total RNA extracted from deparaffinized tissue dissected with a laser capture microdissection system. In addition, extraction of protein yielded 4.9 +/- 2.1 microg/mm2 from a 10-microm-thick rat-liver section, allowing a quantitative expression analysis of protein by Western blotting. Thus, in addition to its advantages for immunohistochemistry, methacarn-fixed paraffin-embedded tissue has benefits for analysis of both RNAs and proteins in the cells of histologically defined areas.

Acetic Acid↗