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Application of PCR amplification of DNA from paraffin embedded tissue sections to linkage analysis in familial retinoblastoma.

A family segregating for the retinoblastoma predisposition gene has been analysed using the polymerase chain reaction to exclude their son as being an affected gene carrier. The unusual feature of this family is that the affected child, who would ordinarily have been used to establish phase in a linkage study, died as a result of developing a second tumour some years ago. The only tissue available from this child was a paraffin embedded, formalin fixed histopathological specimen from the second tumour. It was possible to isolate DNA from this tissue and amplify the DNA flanking two polymorphic restriction enzyme sites to establish alleles which cosegregated with tumour predisposition. Archival material can now be used to offer families such as this prenatal screening to provide informed genetic counselling.

Base Sequence↗

[Production of a monoclonal anti-Cryptosporidium sp. antibody for paraffin-embedded sections].

Since the development of acquired immunodeficiency syndrome, human Cryptosporidiosis has received increased attention. A provisional histological diagnosis can be made on gastrointestinal tract biopsy specimens by light microscopy by showing small round organisms of 2-5 microns attached to the epithelial cell apex. The definitive diagnosis of certitude can only be made by electron microscopy with the identification of various developmental stages of the parasites. We have produced a monoclonal antibody specific to Cryptosporidium sp. usable in paraffin-embedded tissue sections. Such a monoclonal antibody would be an important tool for histological diagnosis of human Cryptosporidiosis.

Acquired Immunodeficiency Syndrome↗

In vivo bromodeoxyuridine incorporation in human gastric cancer: a study on formalin-fixed and paraffin-embedded sections.

Bromodeoxyuridine (BUDR) is a non-radioactive thymidine analogue which is incorporated into the DNA of proliferating cells. This allows evaluation of the size of the S-phase as the BUDR labelling index (BUDR-LI) not only in vitro but also in vivo, since BUDR is not toxic at the doses needed to label cells. To ascertain whether in vivo BUDR incorporation can be detected on routine histological material we tested several different procedures prior to immunoperoxidase staining, on formalin-fixed, paraffin-embedded sections from five patients with gastric cancer, who received BUDR (250 mg m-2, intravenous) 4 h before surgery. To determine the optimal conditions for detecting BUDR in formalin-fixed tissues, immunohistochemical testing for BUDR was performed simultaneously on duplicate sections fixed with 70% ethanol. It was found that hydrolysis with 3N HCl at 37 degrees C for 30 min and digestion with 0.5% in at 37 degrees C for 30 min were sufficient to detect BUDR immunoreactivity in formalin-fixed sections. The method presented extends the range of applications of the in vivo BUDR technique for cell kinetics studies in human neoplasms because it can be used on routinely fixed archival material, with the advantage of correlating the kinetic data with histopathological characters.

Adenocarcinoma↗

[Detection of mixed lymphoid chimerism after allogeneic bone marrow transplantation: demonstration by interphase cytogenetics in paraffin-embedded tissue].

In bone marrow transplantation (BMT) the detection of residual host lymphoid or haematopoietic cells surviving conditioning therapy is because of its association to graft-versus-host disease, graft-versus-leukemia reaction, and relapse of leukemia a matter of great interest. We studied the occurrence of this mixed lymphoid chimerism (MC) in the formol-fixed lymphatic tissue of lymph nodes and spleen from 21 autopsies after allogeneic sex-mismatched BMT (5 females, 16 males, survival 5 to 1140 days after BMT). In situ hybridisation with biotinylated centromer-specific anti-X- and anti-Y-chromosome probes was performed on pepsin-digested paraffin sections. The number of double X-, single X-, and Y-chromosome bearing cells was analysed microscopically. Because of artefacts only 14 cases remained for valid investigation. MC was detected in 6 cases (5 out of 11 males 5 days to 840 days and 1 out of 3 females 76 days after BMT). MC occurred after whole body irradiation with 10 Gy (n = 5) and 7 Gy (n = 1). In 1 autopsy relapse of leukemia caused host cell infiltration. Cases with MC did not express histological signs of acute or chronic graft-versus-host disease, but 5 out of 8 with complete lymphoid chimerism did. The sensitivity of interphase cytogenetics on paraffin embedded tissue is low.

Autopsy↗

Application of the immunoperoxidase technique to formalin fixed, paraffin embedded kidney biopsies.

Different immunohistological methods were compared in 30 renal biopsy cases. The direct immunoperoxidase method gave identical results with immunofluorescence in 88% concerning IgG and C3, while IgA, IgM and fibrinogen have been identically detected by the PAP method in 82%. The non-identical results of the direct method consisted, with one exception, of negative readings, while the non-identical PAP readings were positive with two exceptions. Thus the trypsin-immunoperoxidase method proved to be well applicable on paraffin embedded formalin fixed material. In 10 cases the HRP-labelled direct method was applied also to fresh, frozen sections. It gave almost entirely identical results to immunofluorescence.

Biopsy↗

Measuring c-erbB-2 oncogene amplification in fresh and paraffin-embedded tumors by competitive polymerase chain reaction.

We present an original application of competitive polymerase chain reaction (PCR) for measuring oncogene amplification in DNA from human tumors by simultaneous PCR amplification of genomic DNA with fixed amounts of an internal standard (competitor DNA). Competitors share the same sequence as the target genes but contain an additional 15- to 20-base-pair insert, which allows resolution of the amplified products after polyacrylamide gel electrophoresis and ethidium bromide staining. The gene copy number is derived from the ratio between the intensities of the bands corresponding to the amplified products. Using this procedure, we measured c-erbB-2 amplification in breast and bladder carcinomas in both fresh tumor tissues and paraffin-embedded tissue samples and assessed the precision, sensitivity, and accuracy of the assay. Competitive PCR is a simple, reliable, and accurate method for the evaluation of c-erbB-2 amplification and is potentially suitable for use in the clinical laboratory.

Base Sequence↗

Immunohistological detection of human herpes virus 6 in formalin-fixed, paraffin-embedded lung tissues.

Human herpes virus type 6 (HHV-6) infection is widespread in healthy individuals. The only definite disease association is with exanthem subitum in infants though the virus has been linked with a variety of other diseases including interstitial pneumonitis in bone marrow allograft recipients. In order to investigate the role of HHV-6 in the latter disease we have developed an optimised staining method for the demonstration of specific antigen in routinely processed post-mortem tissues. Formalin-fixed, paraffin-embedded lung tissue from 8 immunocompromised patients who died from interstitial pneumonitis was subjected to immunoperoxidase staining with monoclonal antibodies against HHV-6, cytomegalovirus (CMV), and adenovirus, using a modified avidin-biotin complex (ABC) method. Staining for HHV-6 was obtained in 6 of the 8 patients studied and was present in pneumocytes and macrophages. CMV and adenovirus antigens were identified in 4 and 6 patients, respectively. Whilst the lung tissue of 6 patients contained more than one virus, there was no evidence of cross-reactivity between the monoclonal antibodies. We demonstrated that accurate localisation of HHV-6 using monoclonal antibodies is possible in post-mortem lung tissue and conclude that either HHV-6 alone or in combination with other viruses may play a role in the development of interstitial pneumonitis following bone marrow transplantation or chemotherapy.

Adenoviridae Infections↗

Prediction of disease outcome in melanoma patients by molecular analysis of paraffin-embedded sentinel lymph nodes.

PURPOSE: A significant number of patients who develop recurrence after a histopathologically negative sentinel lymph node (SLN) biopsy will demonstrate occult metastases on re-evaluation of the SLNs with serial sectioning and immunohistochemistry. Reverse transcriptase polymerase chain reaction (RT-PCR) has been evaluated to improve disease staging and avoid false-negative findings in fresh or frozen-section SLNs. The purpose of this study was to develop a multimarker RT-PCR assay for assessing melanoma patients' archived paraffin-embedded (PE) SLNs. PATIENTS AND METHODS: Archived PE histopathologically positive (n = 37) and negative (n = 40) SLNs from patients with primary melanoma were analyzed using a semiquantitative multimarker RT-PCR assay. RESULTS: Marker expression in histopathologically positive and negative SLNs were as follows: 89%, 92%, 35%, and 43% (positive) and 40%, 33%, 5%, and 13% (negative) for tyrosinase, melanoma antigen recognized by T cells-1, tyrosinase-related protein-1, and tyrosinase-related protein-2, respectively. Twenty-five percent of histopathologically negative SLN patients were upstaged using at least two markers. Of these, 80% developed a recurrence. Furthermore, at a median follow-up of 55 months, patients with histopathologically negative SLNs who expressed zero or one marker had a significantly improved disease-free (P <.002) and overall (P <.03) survival versus those expressing two or more markers. CONCLUSION: These findings demonstrate the feasibility of a multimarker RT-PCR assay for evaluating archived PE SLNs. More significantly, identification of molecular risk factors can be detected in histopathologically negative SLNs for distinguishing early-stage melanoma patients with a worse prognosis.

Adult↗

The use of proliferating cell nuclear antigen immunohistochemistry with a unique functional marker to detect postnatal neurogenesis in paraffin-embedded sections of the mature pig brain.

Until recently, evidence supporting postnatal neurogenesis was controversial. Much of the debate has centered on the identification of the dividing cells as neurons versus glia. Because neurogenesis has become a well-documented phenomenon, there is a need for reliable protocols to identify recently divided neurons in a wide range of situations. To facilitate the investigation of postnatal neurogenesis of magnocellular neurons in the pig hypothalamus, a sequential immunohistochemical staining technique was developed for use on serial sections of paraffin-embedded tissue. Proliferating neurons were labeled using mouse-derived monoclonal antibodies to detect proliferating cell nuclear antigen (PCNA) and vasopressin (VP). PCNA, a nuclear protein essential for cell division, identifies recently divided cells in the brains of healthy animals. VP is a unique functional marker for a mature neuron. The presence of a cell with VP positive cytoplasm and a PCNA positive nucleus demonstrates the presence of a VP-producing neuron that has recently divided. This protocol allowed us to safely and accurately label recently proliferated neurons in the mature pig hypothalamus and can be used on archived tissue. This data can be used for further morphometric analysis, as serial sectioning allows for three-dimensional reconstruction of hypothalamic nuclei.

Aging↗

Detection of mycobacterial DNA in cervical granulomatous lymphadenopathy from formalin-fixed, paraffin-embedded tissue by PCR.

Cervical tuberculous lymphadenitis is the most common form of inflammatory neck mass in Korea. The diagnosis of tuberculosis requires proof of the presence of Mycobacterium tuberculosis by acid-fast staining or bacterial growth in culture. However, these are often difficult in cervical tuberculous lymphadenitis. The aim of this study was to investigate the value of the polymerase chain reaction (PCR) technique for detection of mycobacteria in routinely processed tissue sections of cervical granulomatous lymphadenopathy. In this retrospective study, twenty formalin-fixed, paraffin-embedded biopsy specimens from clinically and/or histopathologically diagnosed cervical granulomatous lymphadenopathy were analyzed for mycobacterial DNA by PCR. Two different primers to amplify mycobacterial-common 383-base pair (bp) DNA and Mycobacterium tuberculosis-complex-specific 123-bp DNA were used. Positive PCR products were sequenced directly. Mycobacterial-common DNA (383-bp positive) was found in 10 of the 20 cases. Among them, 7 cases were PCR positive with both primer sets. These seven cases can be considered as tuberculosis. The other three cases indicated possible atypical mycobacteriosis. PCR is a useful technique for the demonstration of mycobacterial DNA fragments in patients with clinically suspected cervical tuberculous lymphadenitis who have acid fast-negative histology and/or unsuccessful mycobacterial cultures.

Base Sequence↗

Demonstration of Epstein-Barr viral DNA in paraffin-embedded tissues of Burkitt's lymphoma from Argentina using the polymerase chain reaction and in situ hybridization.

Burkitt's lymphoma (BL) is the most frequent non-Hodgkin's lymphoma in children in Argentina. Although epidemiologic studies have linked Epstein-Barr virus (EBV) to more than 90% of African BL cases but to only 10-20% of American and French cases, increased EBV-specific antibody titers were demonstrated in 73% of Argentinian patients with BL. To characterize the relationship between EBV and BL in Argentina, we analyzed paraffin-embedded tissues from 16 cases of BL for the presence of EBV DNA using the polymerase chain reaction (PCR) and in situ hybridization (ISH). PCR analysis showed that only 4 of 16 specimens contained the EBV BamW fragment, and these specimens were all from cases diagnosed in 1984. Results of ISH performed with a specific biotinylated DNA probe against the NotI/PstI fragment of EBV correlated with the PCR findings. EBV sequences were detected with ISH in 70-90% of the tumor cells from the 4 positive cases. These data may suggest an epidemic outbreak of EBV-related BL in 1984 superimposed on sporadic cases of BL, for which EBV may not have been an essential factor. This study also demonstrates the value of using molecular techniques on archival tissue to track epidemiologic trends.

Argentina↗

Immunoquantification of cytochrome P-450 3A on rat paraffin-embedded liver tissue.

The cytochrome P-450 3A family is involved in the metabolism of several drugs, including nifedipine, cyclosporine, quinidine and erythromycin. The purpose of this study was to develop a reliable method to obtain a relative quantification of cytochrome P-450 3A apoproteins in rat liver specimens by immunocytochemistry and to correlate such quantification to erythromycin N-demethylase activity, a biochemical pathway sustained by that enzymatic system. Thirty-six male Wistar rats were treated with an injection of either saline or dexamethasone phosphate (10, 30 or 50 mg/kg), a potent inducer of cytochrome P-450 3A. Specimens taken from the same lobe were processed for immunocytochemistry and determination of erythromycin N-demethylase activity. Paraffin sections were treated with a polyclonal antiserum directed against cytochrome P-450 3A. The density of cytochrome P-450 3A immunostaining measured by an automatic image analyzer increased with the dose of dexamethasone pretreatment, and with the erythromycin N-demethylase activity, both parameters being closely correlated. Our data indicate that in rats, when cytochrome P-450 3A is concerned, there is a close correlation between the results of immunoquantitation and biochemical activity. This suggests that such a method of investigation might be used on small paraffin-embedded liver specimens obtained by needle biopsy.

Animals↗

Malignant histiocytosis. Immunohistochemical characterization on paraffin embedded tissue.

Clinically, malignant histiocytosis is a malignant neoplasia with poor prognosis. Diseased are lymphnodes (especially cervical nodes), liver, spleen and bones. Few cases become leukemic. The cells show characteristic pale roundish, often indented nuclei, without large nucleoli and with abundant ill-defined cytoplasm. Phagocytosis of erythrocytes and leukocytes, as well as, hemosiderin deposits may serve as indicators for histiocytic, respectively macrophagic qualities. On touch preparation, tumor cells previously had been marked by acid phosphatase and non-spevific esterase, as being histiocytic. - A comparable marking could be carried out on paraffin embedded material with lysozyme (muramidase) and alpha1-antichymotrypsin, by the indirect immuno-peroxidase technique. No correlation could be proven between any special shape of tumor cells or between different grades of cellular atypism and presence or absence of the immunohistochemical reaction. The reaction with lysozyme and alpha1-antichymotrypsin was also tested in other tumors and was found to be positive in a variety of different tumor cells showing degenerative changes, respectively necrobiosis. - But lysozyme and alpha1-antichymotrypsin are markers characteristically found in histiocytes, respectively histiocytic tumor cells. They are apparently less distinct in MH with a larger number of immature histiocytic tumor cells.

Adolescent↗

Immunohistochemical staining for DNA topoisomerase II in frozen and formalin-fixed paraffin-embedded human tissues.

DNA topoisomerase II is the molecular target of several clinically useful chemotherapeutic drugs. The sensitivity of cells to drugs that target topoisomerase II is dependent on the cellular content of this enzyme. Drug-sensitive cells have elevated amounts of type II topoisomerase. To determine relative amounts of enzyme in malignant neoplasms, we developed an in situ immunohistochemical stain for topoisomerase II. The stain uses either polyclonal or monoclonal antibodies produced against the alpha isoform of the enzyme. Staining can be done on both frozen and formalin-fixed, paraffin-embedded tissues. By using this immunostain, we found marked differences in enzyme content in several human malignancies.

Animals↗

New monoclonal antibodies recognizing epidermal differentiation-associated keratins in formalin-fixed, paraffin-embedded tissue. Keratin 10 expression in carcinoma of the vulva.

Two monoclonal antibodies (MAb) specific for differentiation-related epidermal keratins have been developed. They represent specific molecular probes for different stages of epidermal differentiation. Antibody DE-K10 is chain-specific for cytokeratin polypeptide no. 10 (56.5 kD) expressed in all suprabasal layers of the epidermis. Antibody DE-SCK is specific for modified stratum corneum keratins and thus represents a marker for the terminal step of epidermal differentiation. Since the epitopes identified by both antibodies are preserved in formalin-fixed, paraffin-embedded tissue sections, these antibodies can be used for retrospective studies of differentiation in various pathological processes. We have used antibody DE-K10 to study the cytokeratin 10 expression in 26 stage II or III vulvar squamous cell carcinomas. Preliminary data suggest an increased risk of recurrence in cytokeratin 10 negative tumours.

Antibodies, Monoclonal↗

Application of a monoclonal antibody for the detection of Trichosporon beigelii in paraffin-embedded tissue sections.

Trichosporon beigelii is a normal inhabitant of soil and is occasionally found as normal flora of the skin and mouth. Opportunistic infection by this fungus has been increasingly reported in immunocompromised patients. The diagnosis of this infection depends on positive cultures or histological evidence. However, it is sometimes difficult to distinguish this fungus from Candida species in tissue section. We have generated two monoclonal antibodies that can distinguish T. beigelii from other fungi including several species of Candida. One of these antibodies (K-16) reacts with T. beigelii in formalin-fixed, paraffin-embedded tissue sections and will be useful as an aid to the accurate diagnosis of trichosporonosis.

Antibodies, Fungal↗

In situ detection of human Ig light-chain mRNA on formalin-fixed and paraffin-embedded tissue sections using digoxigenin-labelled RNA probes.

Digoxigenin-labelled RNA probes complementary to human immunoglobulin (Ig) kappa and lambda light-chain mRNAs were produced by in vitro transcription. Using these probes, several existing in situ hybridization protocols were studied. By modifying and optimizing pretreatment procedures, which include hybridization, stringency washings and probe detection, a simplified non-radioactive in situ hybridization method for Ig light-chain mRNAs was developed. The light-chain signals were consistently identified in plasma cells, germinal centrocytes, centroblasts and immunoblasts in formalin-fixed and paraffin-embedded sections of lymphoid tissues. Monotypic light-chain mRNA was demonstrated in archival cases of kappa or lambda light-chain-restricted B-cell lymphoma. Background staining was found to be negligible in all the tissues tested. These results indicate that the in situ hybridization methodology described in this study is specific and sensitive for the detection of Ig light-chain mRNAs and has practical value in routine histology.

Antisense Elements (Genetics)↗

Quantitative analysis of mast cells in benign and malignant breast lesions. Immunohistochemical study on formalin-fixed, paraffin-embedded tissues.

BACKGROUND: It has been reported that the number of mast cells was significantly greater in malignant breast carcinomas than in benign breast lesions. This was due to tryptase-containing mast cells while tryptase, chymase-containing mast cells had no effect. However, analysis of mast cells in breast carcinomas and benign breast lesions based on their histological findings remains to be elucidated. METHODS: Using immunohistochemical methods morphological examinations of mast cells were undertaken in benign and malignant breast tissues from 51 patients (30 benign, 21 malignant), which were formalin-fixed and paraffin-embedded. In the study with malignant breast tissues, samples of malignant tissues and adjacent healthy tissues were obtained from a single patient, and the number of mast cells was compared. RESULTS: Among benign breast tissues, the number of mast cells in intracanalicular fibroadenoma was significantly lower than that in pericanalicular fibroadenoma as well as that in mastopathy. The number of mast cells was significantly greater in malignant lesions than that in benign lesions. The number of mast cells in scirrhous carcinoma and that in solid-tubular carcinoma were significantly increased compared with that in adjacent healthy tissues. In addition, the number of mast cells in scirrhous carcinoma was highest among breast carcinomas, and significantly greater than that in papillotubular carcinoma. CONCLUSION: We were the first to find the significant lower number of mast cells in intracanalicular breast fibroadenoma when compared with that in pericanalicular fibroadenoma as well as that in mastopathy. Moreover, the number of mast cells in scirrhous carcinoma was significantly greater than that in papillotubular carcinoma.

Adult↗