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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↗

Immunohistochemical detection of hog cholera viral glycoprotein 55 in paraffin-embedded tissues.

Formalin-fixed, paraffin embedded tissues obtained from 40 pigs inoculated with a field isolate of hog cholera virus were examined for the presence of Gp55, a major structural protein of the virus envelope, using a monoclonal antibody-based immunohistochemical test with the avidin-biotin-peroxidase complex method. Immunoreactivity was detected in hog cholera virus-infected tissues but not in control pigs tissues, African swine fever virus-infected tissues, or bovine viral diarrhea virus-infected porcine or bovine tissues. The first positive reactions were seen in lymphatic tissues, digestive tract and skin on postinoculation day (pid) 4, respiratory and urinary tissues on pid 5, nervous tissues on pid 6, and endocrine tissues on pid 7. These staining reactions persisted until the last observation on pid 18. Hog cholera virus antigen was not detected in heart tissue at any time. The highest levels of antigen detection were found in tonsils, spleen, and pancreas, although the esophageal mucosa and skin epithelial cells were also intensely and widely stained. The cellular staining pattern of Gp55 had a ubiquitous distribution. It was found in epithelial cells, macrophages and circulating monocytes, endothelial cells, lymphoid cells, and glial cells. The results showed a high specificity and high sensitivity for detecting hog cholera Gp55 in formalin-fixed, paraffin embedded tissue samples. This method allows precise association of Gp55 with specific cells, tissues, and histologic lesions, making the technique suitable for use in routine diagnosis of hog cholera.

Animals↗

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↗

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↗

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↗

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↗

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↗

Improved flow cytometric determination of proliferative activity (S-phase fraction) from paraffin-embedded tissue.

Recent studies suggest that proliferative activity (S-phase fraction [SPF]) may have greater prognostic significance than total nuclear DNA content; however, relatively few studies have examined SPF from paraffin-embedded tissue because of significant contamination of histograms with debris. In this study, cell cycle analysis was performed on 124 matched tissue specimens. Fresh tissue was divided into two equal portions; one portion was frozen, whereas the other portion was processed and embedded in paraffin. S-phase could be determined for both frozen and paraffin-embedded tissue in 81 cases. Correlation between SPF from frozen and paraffin-embedded tissue was demonstrated (r = 0.80) when debris was subtracted from histograms with the use of two new subtraction algorithms referred to as multicut and singlecut. Unlike other debris-subtraction algorithms, the quantity and distribution of debris calculated by these algorithms are dependent on the magnitude and position of histogram peaks. A lesser degree of correlation was demonstrated with the use of a standard exponential debris subtraction algorithm (r = 0.67). Correlation of SPF for aneuploid cases was greater when SPF was calculated as a percentage of the aneuploid cell population rather than as a percentage of the entire cell population. This was attributed to the observation that the proportion of aneuploid cells from paraffin-embedded tissue was less than that from frozen tissue. The results of this study indicate that SPF can be calculated from paraffin-embedded tissue with values comparable to those obtained from frozen tissue. The ability to calculate SPF reliably from paraffin-embedded tissue should allow additional evaluation of this parameter as a prognostic indicator.

Algorithms↗

In situ-PCR for the detection of Mycobacterium paratuberculosis DNA in paraffin-embedded tissues.

Molecular biological techniques have permitted the rapid and sensitive detection of the Mycobacterium paratuberculosis genome in infected tissues, most commonly by polymerase chain reaction amplification of sequences in the IS900 DNA insertion sequence. The aim of this work was the detection of M. paratuberculosis DNA in ovine tissues by in situ-polymerase chain reaction, which is sensitive and localises the signal within the tissue sample. Paraffin embedded tissues from three acid-fast positive ovine guts with classical lesions of paratuberculosis, and from negative control samples were tested. A 413-bp fragment of the IS900 sequence was amplified in-situ and hybridised to an internal PCR-synthesised digoxygenin-labelled probe. The samples from sheep affected by paratuberculosis clearly showed cell-specific cytoplasmic signals in mucosal and submucosal macrophages. This technique could be useful both in the diagnosis and study of the pathogenesis of infections in which involvement of M. paratuberculosis is suspected.

Animals↗

Mutations in BRCA1 from fixed, paraffin-embedded tissue can be artifacts of preservation.

DNA isolated from paraffin-embedded tissues has been used for analysis of DNA alterations in disease states. Use of archival tissue can expedite the gathering of large numbers of specimens from rare disease subtypes that would take years to accumulate prospectively. Therefore, archival tissues from 70 ovarian cancer cases diagnosed before or at age 40 were retrieved for analysis of BRCA1 mutations. DNA was isolated from paraffin-embedded tissue of 70 ovarian cancer cases diagnosed before or at age 40. BRCA1 mutation analysis was conducted by single-strand conformation polymorphism analysis and DNA sequencing. Fifty-eight BRCA1 mutations were found in 34 of the 70 ovarian cancer cases. Twenty-two cases had one mutation each and 12 cases had multiple mutations. Multiple mutations found in histologically normal tissue of 2 cases were not present in matched tumor tissue. For another case, DNA from two separate blocks of normal tissue contained different mutations. These observations were anomalous and suggested that mutations detected in fixed tissues may be artifacts of tissue preservation and not present in the original unfixed tissues. To test this suggestion, blood was obtained from 2 patients for whom mutations were found in fixed, normal tissue. DNA from their unfixed lymphocytes did not contain the mutations found in fixed normal tissue. Thus, mutations found in fixed, paraffin-embedded tissues can be artifacts of tissue preservation. The reliability of DNA sequence data derived from such tissues must be questioned in the absence of corroborating data from unfixed tissues. This severely limits the use of fixed tissues as a source of DNA for retrospective research and for clinical genetic testing in families for which a disease-affected member is not alive.

Adult↗

[Flow cytometric DNA analysis of gynecologic malignant tumors using paraffin-embedded tissue].

We have studied flow cytometric DNA analysis of gynecologic malignant tumors using paraffin-embedded tissue for histopathology. A close correlation was observed between the DNA indices obtained from fresh unfixed tissue and from paraffin-embedded tissue (r = 0.993). The coefficient of variation (CV) for the diploid G0G1 peak of the paraffin-embedded tissue was one and half greater than that obtained from fresh tissue on the average. In the DNA analysis of 64 endometrial carcinomas, DNA aneuploidy was detected in 3% of nuclear grade 1, in 25% of nuclear grade 2 and in 63% of nuclear grade 3. That is, the more abnormal the nuclear findings, the higher the percentage of DNA aneuploidy. In the analysis of 48 ovarian tumors, DNA aneuploidy was detected in 79% of serous adenocarcinoma, in no of mucinous adenocarcinoma, in 17% of endometrioid carcinoma, in all of clear cell carcinoma and dysgerminoma, that is, its incidence was different among histological subtypes.

Aneuploidy↗

[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↗

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↗

[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↗

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↗

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↗

[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↗

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↗