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At least 667 records · Page 37Linked to original sources
PubMed1999

Detection of Mycobacterium avium subspecies avium in formalin-fixed, paraffin-embedded tissues of captive exotic birds using polymerase chain reaction.

A presumptive diagnosis of avian tuberculosis can be made when characteristic histologic lesions and acid-fast bacilli are observed in avian tissue samples. However, a definitive diagnosis requires isolation and identification of the causative organism, a process that can take several weeks to complete. The purpose of the study was to determine whether formalin-fixed, paraffin-embedded archival avian tissues could be tested by polymerase chain reaction (PCR) to reliably and rapidly diagnose avian tuberculosis. Tissues were examined from both presumptive and definitive cases of avian tuberculosis from captive exotic birds obtained over a 14-yr period (1983-1997). The cases chosen consisted of birds that had characteristic histologic lesions with acid-fast bacilli. The primers used for PCR amplified a 180-base-pair fragment of 16S ribosomal RNA, a sequence specific for both Mycobacterium avium subsp. avium and M. avium subsp. paratuberculosis. If a sequence was detected in a sample, it was presumed that M. a. avium was the organism being detected. This M. avium fragment sequence was detected in 26 of the 97 samples (27%). Some of the negative PCR results may be explained by any of several factors that adversely affect nucleic acid integrity, particularly prolonged fixation in formalin. Of the 17 samples that were culture positive for M. avium and were known to have been fixed in formalin for < or = 4 wk, 11 tested positive by PCR (65%). The findings of this study show that PCR can be a rapid indicator of the presence of M. a. avium in formalin-fixed, paraffin-embedded tissues. However, the relatively low detection rate the test demonstrated in this sample set may limit its practical use as a diagnostic tool.

Air Sacs↗
PubMed1993

DNA amplification by polymerase chain reaction from brain tissues embedded in paraffin.

A method which enables analysis of DNA from archival paraffin embedded normal and malignant brain tissue is described. The demonstration of a 317-bp long beta-actin DNA sequence by the polymerase chain reaction (PCR) was used to identify which fixation procedure, deparaffinization time and DNA extraction procedure would give the best results. Tissue specimens 1-39 years old were included in the experiments. Specimens fixed in either 10% formalin, Carnoy's or AMeX fixative were found to be best suited for subsequent analysis by PCR. Paraformaldehyde and acetone compromised amplification efficiency, while Bouin's fixed tissue gave uniformly negative results. Regardless of fixative used, PCR reaction had to be run through at least 40 cycles. Prolonged deparaffinization time and phenol/chloroform extraction of DNA did not influence DNA quality as a template for PCR reaction. Formalin fixed brain tumours can be successfully used for DNA/PCR analysis even if they are up to 39 years old.

Base Sequence↗
PubMed1993

[Variation of the diploid pattern in tissues used as normal controls of solid tumors: advantages and disadvantages of flow cytometric analysis of paraffin-embedded tissues].

The aim of the present work was to study the factors that influence the variation of diploid patterns in 75 areas of histologically normal gastric tissue, located in surgically resected stomachs due to early gastric cancer. Each sample was used as a diploid reference of its respective tumoral area. Fifty five samples were embedded in formalin and 20 corresponded to fresh tissue. It was found that in the older tissues, the cellular debris increased, the localization channel of the peaks shifted to the left (lower than channel 60) and the peak shape was deformed, with an increase in the variation coefficient (around 6) and an elevation and lengthening of phase S. When fresh tissue was used, the first peak was localized around channel 60-70, with a significant reduction of cellular debris, a lower variation coefficient amplitude (2-5) and a phase S adhered to the basal line. Aiming to observe the influence of paraffin embedding over time, 21 tissue samples originally assayed as fresh tissues, were reanalyzed one year later. The same alterations initially observed in old tissues were again noticed. According to these results, it is necessary to select adequate controls for flow cytometric analysis to obtain an adequate histogram interpretation, and specially to calculate the ADN index.

Adult↗
PubMed1990

Production of a monoclonal antibody as immunohistochemical marker on paraffin embedded tissues using a new immunization method.

This report describes a method for the production of murine monoclonal antibodies (MAbs) against cellular antigens preserved during formol fixation and paraffin embedding of human tissues in an attempt to select markers that would be useful in immunopathology. Hybridomas were prepared using spleen cells from mice immunized with cell suspensions obtained from formalin-fixed paraffin block sections of a human breast carcinoma. A monoclonal antibody 83 D4 was selected, which was reactive with paraffin embedded breast carcinoma tissues, but not with normal breast. The reactive antigen has a high molecular weight (400-1000 kD) and was detected on the cell surface of live human breast cancer cell lines and on frozen tissues sections. These results demonstrate that the MAb 83 D4 identifies a native breast tumor associated epitope conserved during tissue fixation and embedding and could be used as an immunohistochemical marker.

Antibodies, Monoclonal↗
PubMed1991

Automated procedure for dewaxing and rehydration of paraffin-embedded tissue sections for DNA flow cytometric analysis of breast tumors.

Flow cytometric DNA analysis of paraffin-embedded tumors is an important diagnostic and prognostic tool in clinical pathology. The technique is limited, however, by the time-consuming multistep procedure for dewaxing and rehydrating tissue. The authors developed an automated procedure to complete the dewaxing and rehydration of tissue using a routine histologic tissue processor with a 24-hour timer. This technique provided excellent tissue recovery and reproducible DNA histograms comparable to those obtained by manual methods. Subsequently, the authors analyzed the DNA content of 93 paraffin-embedded breast cancer tissues. The automation of a significant portion of the routine processing required for paraffin-embedded tissue makes cytometric DNA analysis a more practical procedure in the laboratory.

Automation↗
PubMedDate not supplied

On-grid immunogold labeling of glial intermediate filaments in epoxy-embedded tissue.

On-grid immunogold labeling of structures like intermediate filaments has been difficult to achieve. Presumably this is because such structures are thinner than the thin sections themselves and because gold-labeled reagents remain on the surface and do not penetrate epoxy resins. Many pathologic and other tissues, however, are primarily available as epoxy-embedded blocks, and a postembedding gold procedure capable of detecting such thin structures would be useful. This study aimed to investigate the astrocytic intermediate filament antigen glial fibrillary acidic protein (GFAP) in glutaraldehyde-fixed, epoxy-embedded brain biopsy tissue from a child with Alexander's disease. A protocol was developed for performing on-grid immunogold labeling which minimized nonspecific deposition of gold reagent. The method utilized ovalbumin and skim milk in the washes and diluent for the gold reagent and the same solution with added Tween-20 and high sodium chloride in the diluent for antibodies and normal serum. In grids etched with metaperiodate and hydrogen peroxide, the astrocytic intermediate filaments were only occasionally and sparsely labeled. When an etching procedure with sodium ethoxide was employed, however, extensive labeling was obtained on the astrocytic intermediate filaments. In contrast, the larger, pathological Rosenthal fibers characteristic of Alexander's disease were labeled after both etching procedures, but labeling was enhanced after ethoxide etching. Postosmicated material showed much less labeling. The findings demonstrate that postembedding procedures can be used with epoxy-embedded material to immunolabel thin structures like intermediate filaments.

Cytoskeleton↗
PubMed2004

Apoptosis in normal lymphoid organs from healthy normal, conventional pigs at different ages detected by TUNEL and cleaved caspase-3 immunohistochemistry in paraffin-embedded tissues.

The frequency and the distribution of apoptotic cells were investigated in formalin-fixed paraffin-embedded lymphoid tissues from healthy conventional pigs at four different ages (6 days, 2 months, 3.5 months and 5 months). Samples of tonsil, mesenteric lymph node, spleen, thymus and Peyer's patches were histologically processed and apoptosis evaluated with the TUNEL reaction and cleaved caspase-3 immunohistochemistry. In each technique, quantification of positive labelling was done for each particular lymphoid tissue area. The labelling pattern and distribution were similar for TUNEL and cleaved caspase-3. TUNEL stained mainly apoptotic bodies inside macrophages, but signal was also seen in free apoptotic bodies and in the nuclei of lymphocyte-like cells. The anti-cleaved caspase-3 antibody labelled mainly nuclei of lymphocyte-like cells. All tissues presented a similar distribution pattern of apoptosis, except for the 6-day-old group. In this group, a scattered distribution of positive cells was detected in tonsil, lymph node and spleen. In the tonsil and mesenteric lymph nodes from the older pigs, follicular areas presented higher amounts of positive cells than interfollicular areas. Moreover, the splenic white pulp showed more positive reaction than the red pulp, especially when they included germinal centres. In all groups, the follicular areas of ileal Peyer's patches presented more labelled cells than the dome and the lamina propria. In the thymus, the higher apoptotic rates were found in the cortex. In general, TUNEL yielded higher rates of positive cells than cleaved caspase-3 immunolabelling. A good correlation between the two techniques was found for thymus, tonsil and mesenteric lymph node, but not for Peyer's patches and spleen. This study describes a detailed histochemical characterization of apoptosis in pig lymphoid tissues using TUNEL and a cleaved caspase-3 immunolabelling at different ages. Moreover, our results indicate that TUNEL and cleaved caspase-3 techniques can be equivalent only when tissues have a high or low levels of apoptosis, since a considerable discrepancy was found in intermediate situations. Data from this study should be useful for future comparative studies under disease conditions.

Age Factors↗
PubMed1993

Detection of immunoglobulin gene rearrangement of B cell non-Hodgkin's lymphomas and leukemias in fresh, unfixed and formalin-fixed, paraffin-embedded tissue by polymerase chain reaction.

BACKGROUND: The majority of B cell nonHodgkin's lymphomas (NHLs) are composed of a genotypically identical cell population characterized by a unique immunoglobulin (Ig) VDJ gene rearrangement which is customarily documented by Southern blot hybridization analysis of fresh tissue. Sometimes, however, this approach cannot be used because of an insufficient quantity of tissue or the unavailability of fresh tissue. Therefore, alternative strategies should be designed in order to overcome these limitations. EXPERIMENTAL DESIGN: One possible alternative is the identification of Ig VDJ products of normal and neoplastic B cells by polymerase chain reaction (PCR) using mixed oligonucleotide primers recognizing the framework III region or Ig variable heavy chain leader sequences and universal Ig heavy chain joining region (JH) oligonucleotide primers. To determine whether the respective DNA samples are suitable for PCR amplification, control and unrelated genes should also be investigated (exon 5 of the p53 gene). In this study, genomic DNA was extracted from a well characterized panel of 139 human B cell lymphoid leukemias and NHLs derived from fresh (84) and/or paraffin-embedded (55) tissue, 19 normal peripheral lymphoid tissues, 9 Epstein-Barr virus infected lymphoblastoid cell lines and, as negative controls, 11 T cell LLs. Clonal Ig gene rearrangement products were assessed for the presence of a distinct PCR fragment after framework III-JH PCR amplification and electrophoretic separation and by DNA sequencing of the cloned PCR-Ig fragments. RESULTS: Eighty-eight of the 139 (63%) B-NHLs consisting of 53/84 (63%) fresh, unfixed and 35/55 (64%) formalin-fixed, paraffin-embedded samples, exhibited distinct PCR bands. Using this approach we were able to identify a single clonal B cell population mixed with 1,000 nonB cells or 5 polyclonal B cells. There was no difference in the detection of monoclonality among different B-NHL categories. PCR fragments were not identified in any of 27 normal lymphoid tissues or 11 T-lymphoid leukemias. To detect a larger number of Ig gene rearrangement products, genomic DNA of 12 B-NHL/lymphoblastoid cell lines were investigated using VH-specific leader and JH oligonucleotides by PCR. A single PCR product was obtained in 9 of 12 (75%) cases and their clonality was documented by DNA sequencing of the cloned PCR fragments. The clonality of 11 of the 12 (92%) cases could be demonstrated using both PCR approaches. CONCLUSIONS: Our results suggest that the monoclonality of human neoplastic B cells can be efficiently evaluated by PCR equally well from fresh, unfixed and formalin-fixed, paraffin-embedded tissues. This technique should prove to be a powerful tool in clinical diagnosis and research as well as in the retrospective analysis of archival pathologic specimens.

Base Sequence↗
PubMed1988

Technical and statistical improvements for flow cytometric DNA analysis of paraffin-embedded tissue.

Flow cytometric DNA analysis of paraffin-embedded solid tumors has permitted review of large series of archival tissue in attempts to relate abnormal DNA content to prognosis. Limitations of the technique include: 1) a laborious, time-consuming procedure; 2) variation in technique between laboratories; and 3) lack of an objective method of computing DNA indices. Critical evaluation of our technique has shortened the time involved in dewaxing and rehydration, selectively utilized patient's own normal tissue as the internal standard, proved reproducibility of stored specimens, standardized DNA index computation, and developed a statistical analysis to confirm aneuploidy. These technical improvements and the development of a statistical analysis provide a way to shorten the procedure time and standardize the data generated from flow cytometric DNA analysis so as to improve the quality of retrospective reviews of paraffin-embedded tumors and accelerate the definition of flow cytometry's role as a prognostic indicator.

Breast Neoplasms↗
PubMedDate not supplied

Immunohistochemical detection of P-glycoprotein on frozen and paraffin-embedded tissue sections of normal and malignant tissues.

In this study the reactivity of the monoclonal antibodies (mabs) C 219, C 494 and 4E3 was compared on frozen and paraffin-embedded normal tissues and tumors. On frozen tissues we used an indirect immunoperoxidase method, while on paraffin sections a streptavidin-biotin method without antigen retrieval methods was used. In normal tissues all mabs were reactive with colon epithelium in frozen and paraffin-embedded sections. The bile canaliculi in the liver showed the most extensive reaction with C 219 in frozen sections, and to a lesser extent with C 494 and 4E3. C 219 reacted with the pancreatic acinar and ductal epithelium, whereas C 494 and 4E3 reacted predominantly in the stroma. The kidney showed positivity for all mabs in the collecting ducts and isolated solitary cells were reactive in the spleen. In the skin the eccrine part of the sweat glands was reactive for all mabs in paraffin sections. The lung, prostate and breast were negative for all mabs. Only in paraffin sections of various tissues did the C 494 appear to be reactive with nerve fibers and ganglion cells. Colon cancers were positive for P-170 with all mabs tested. In breast carcinoma C 494 showed positive reactions in 8/26 frozen and 4/22 paraffin sections, while 4E3 was reactive with 20/25 frozen but only with 1/21 paraffin sections. C 219 gave similar results in frozen (22/26) and paraffin (17/26) sections of breast cancer. Ovarian carcinomas were positive with C 494 in 11/20 of the frozen and in 11/15 of the paraffin sections, while 4E3 again reacted more weakly in paraffin (5/15) than in frozen (15/20) sections. C 219 gave positive reactions in all ovarian carcinomas in frozen (20/20) and paraffin sections (14/14). In the tumors, the most intense reaction for all mabs was obtained in the colon, followed by the ovary and breast. Enhanced staining was seen in paraffin sections for mab C 494 in ovarian carcinoma. By demonstrating the presence of both an external and internal epitope on frozen sections, the combined use of 4E3 and C 219 gave complementary information about the expression of P-170.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2006

Characterization of anti-TIMP-1 monoclonal antibodies for immunohistochemical localization in formalin-fixed, paraffin-embedded tissue.

The aim of this study was to evaluate seven anti-TIMP-1 (tissue inhibitor of metalloproteinase-1) monoclonal antibodies by immunohistochemical (IHC) staining of formalin-fixed, paraffin-embedded (FFPE) tissue. Detection of the TIMP-1 protein was studied by IHC in FFPE human archival normal and neoplastic samples. Indirect IHC technique was used, and the seven antibodies (clones VT1, VT2, VT4, VT5, VT6, VT7, and VT8) were tested in various concentrations using different pretreatment protocols. All seven VT antibodies specifically immunostained the cytoplasm of islets of Langerhans cells in normal pancreas, epithelial cells of hyperplastic prostate, tumor cells of medullary thyroid carcinoma, and fibroblast-like cells of malignant melanoma. Specificity of the anti-TIMP-1 antibodies was confirmed by several controls, e.g., Western blotting on proteins extracted from FFPE tissue showed that the VT7 antibody reacted specifically with a protein band of approximately 28 kDa, corresponding to the molecular mass of TIMP-1. However, sensitivity varied with the different antibodies. Use of heat-induced epitope retrieval (HIER) and the VT7 clone applied at low concentrations demonstrated more intense immunoreactivity with the TIMP-1-positive cell types compared to the other six clones. Furthermore, when tested on a range of normal and neoplastic endocrine tissues, the VT7 clone demonstrated immunoreactivity with all neuroendocrine cell types. In conclusion, all seven antibodies detected TIMP-1 protein in various normal and neoplastic FFPE tissues, but one clone, VT7, was superior for IHC staining of TIMP-1 in FFPE tissue sections when using HIER.

Antibodies, Monoclonal↗
PubMed2007

Immunohistochemical detection of 3 viral infections in paraffin-embedded tissue from mink (Mustela vison): a tissue-microarray-based study.

Immunohistochemical (IHC) assays were developed and tested for the detection of 3 viral infections in archived paraffin-embedded mink tissue. Specimens had been obtained from mink with diagnoses of acute Aleutian disease (AD), mink parvoviral enteritis (MVE), or canine distemper (CD) made by means of routine diagnostic procedures. To improve the efficiency and reduce the costs of IHC analyses, tissue microarray (TMA) technology was used. Representative cores 2 mm in diameter from each tissue specimen and from positive- and negative-control specimens were collected in a TMA block. Immunohistochemical reactions to viral antigens were assessed and graded. Positive reactions were found in 91% of the 32 specimens from mink with AD, 53% to 80% of the 60 specimens from mink with MVE, and all 66 of the specimens from mink with CD. To validate the use of TMAs, the IHC methods were applied to whole-mount paraffin-embedded sections of 10 of the positive specimens for each disease, together with whole-mount sections of small intestine and lung tissue from 2 healthy mink. The IHC grading of the TMA cores and the whole-mount sections from the same animal corresponded completely. These results suggest that IHC demonstration of viral antigen allows rapid and reliable diagnosis of the 3 viral infections in mink and is a potential supplement to histologic diagnostic procedures. The TMA technique proved useful for screening large numbers of samples for expression of specific viral antigens, while reducing overall costs.

Aleutian Mink Disease↗
PubMed1997

Interphase cytogenetic analysis of myxoid soft tissue tumors by fluorescence in situ hybridization and DNA flow cytometry using paraffin-embedded tissue.

BACKGROUND: Myxoid liposarcoma is one of the major myxoid malignancies of soft tissue and its histologic differentiation from other myxoid tumors is sometimes difficult. Recent cytogenetic analysis revealed that a characteristic reciprocal chromosomal translocation of t(12;16)(q13;p11) occurs in myxoid liposarcomas. In this study, retrospective cytogenetic analysis by means of fluorescence in situ hybridization (FISH) and DNA flow cytometry were performed on free nuclei isolated from paraffin embedded myxoid liposarcoma cells, and they were compared with myxoid malignant fibrous histiocytomas (MFHs), low grade fibromyxoid sarcomas, and intramuscular myxomas. METHODS: Nine myxoid liposarcomas, five myxoid MFHs, two low grade fibromyxoid sarcomas, and four intramuscular myxomas were examined. Chromosomal aberrations in chromosomes 12 and 16 were investigated by FISH, using both centromeric DNA probes and whole chromosome painting probes. Cellular DNA contents were determined by flow cytometry. RESULTS: All nine myxoid liposarcomas were shown to be diploid by DNA flow cytometry and exhibited the translocation t(12; 16), as shown by FISH. Four of the five myxoid MFHs exhibited aneuploidy, as shown by flow cytometry, and remarkable numeric aberrations of chromosomes 12 and 16. No abnormal DNA content or chromosomal aberrations were identified in the two low grade fibromyxoid sarcomas or the four intramuscular myxomas. CONCLUSIONS: FISH analysis performed on paraffin embedded materials can be used to differentiate myxoid liposarcomas from other myxoid soft tissue tumors.

Adult↗
PubMed2005

Molecular diagnosis of Ewing's sarcoma/primitive neuroectodermal tumor in formalin-fixed paraffin-embedded tissues by RT-PCR and fluorescence in situ hybridization.

Recent studies have suggested that formalin-fixed paraffin-embedded (FFPE) tissues can be used for molecular analyses by fluorescence in situ hybridization (FISH) and RT-PCR. We analyzed 18 cases of ES/PNET for the t(11;22)(q24;q12) and t(21;22)(q22;q12) fusion transcripts by RT-PCR and analyzed for EWS translocation by interphase FISH with a dual color fusion probe to compare these two approaches directly. RT-PCR detected 13 (72%) EWS-FLI-1 fusions (type I=10, type II=3) and 2 (11%) EWS-ERG fusions. Three cases could not be evaluated because the housekeeping gene phosphoglycerate kinase (internal mRNA control) was not amplified. FISH was diagnostic in 15 of 18 cases (83%). There were three discordant cases between RT-PCR and FISH (concordance of 83%). Using a combination of RT-PCR and FISH, the results were complementary. One advantage of RT-PCR analysis was that subtypes of EWS translocation could be determined specifically (type I, type II and ERG). These findings indicate that because of the difficulties and limitations associated with the molecular analysis of FFPE tissues, a combination of RT-PCR and FISH may be a better approach to enhance the sensitivity and accuracy of detecting ES/PNET translocations in FFPE tissues with suboptimally preserved nucleic acids.

Base Sequence↗
PubMed1992

Immunolabelling of prolactin at ultrastructural level using the protein A-gold technique on Epon-embedded tissue.

The use of the colloidal-gold technique in electron microscopy immunocytochemistry has provided important information on the in situ localisation of intracellular antigens. We have developed a post-embedding technique for prolactin localisation on resin-embedded human pituitary tissue sections by the use of the protein-A gold conjugate. Human pituitary tissue obtained at autopsy was processed for electron microscopical study without post-osmication and then embedded in Epon. The indirect immunoperoxidase method was used for light microscopical targetting of lactotroph cells for subsequent electron microscopical antigen localisation. Ultra-thin sections were labelled with human anti-human prolactin followed by protein-A gold conjugate. Specific labelling was observed over secretory granules with a density of 15-30 particles per granule, as determined by the Quantimet 570 image analysis system. This technique provides a means of studying the pathophysiology of hormonal secretion at ultrastructural level and can be a useful tool in diagnostic and research investigations.

Epoxy Resins↗
PubMed2000

Immunoglobulin heavy-chain gene rearrangement studies by Southern blot using DNA extracted from formalin-fixed, paraffin-embedded tissue.

BACKGROUND: In most clinical molecular diagnostics laboratories, Southern blots for gene rearrangement studies are not routinely performed on formalin-fixed, paraffin-embedded (FFPE) tissue samples. In this study, immunoglobulin heavy-chain gene rearrangements by Southern blot using DNA extracted from FFPE tissue samples were studied. METHODS AND RESULTS: Eleven paired freshly frozen and FFPE tissue samples were evaluated for immunoglobulin gene rearrangements by PCR and Southern blot analyses. An additional 14 selected samples sent to our laboratory to rule out lymphoma, for which only FFPE tissue (no frozen tissue) was available and for which PCR was interpreted as negative, were evaluated by the same techniques. Southern blots generated from DNA extracted from FFPE tissues were qualitatively identical to those generated from DNA extracted from fresh or freshly frozen tissue and correlated well with the final diagnoses. Ten interpretable Southern blots were generated in the 14 cases in which no frozen tissue was available. Four of these ten blots were interpreted as positive for an immunoglobulin gene rearrangement. Although the number of samples analyzed is small, success with Southern blotting correlated with increased sample size and sample width (1.17 vs 0.49 cm(2); P <.024; 0.71 vs 0.43 cm; P <. 049, respectively). CONCLUSION: DNA extracted from FFPE tissue samples using the simple, efficient, and nontoxic techniques described in this report can be used in many cases for Southern blotting for the detection of clonality by gene rearrangement studies.

Blotting, Southern↗
PubMed1995

[A molecular pathological study on the localization of the human papillomavirus using nested PCR and in situ hybridization methods in paraffin embedded tissues].

This study was designed to use nested polymerase chain reaction (nested PCR), in situ hybridization (ISH) and immunohistochemical techniques to identify human papillomavirus (HPV) in tissues fixed in formalin and embedded in paraffin. Eighty cases including 17 cases of condyloma acuminatum, 10 cases of cervical dysplasia, 6 cases of carcinoma in situ, 16 cases of squamous cell carcinoma of the uterine cervix, 14 cases of nasal and paranasal papilloma, 1 case of transitional cell papilloma and 16 cases of esophageal squamous cell carcinoma were examined. With the nested PCR method, the positive reaction rate of HPV was higher than with the single step PCR method. The detection rate was about ten-fold higher in condyloma acuminatum and two times higher in cervical dysplasia with the nested PCR method. In four cases of condyloma acuminatum, ISH was positive. Three of those cases were type 18 HPV and the another was type 11 HPV. Immunohistochemically, HPV was detected only in the cases of condyloma acuminatum. The nuclei of superficial epithelial cells, especially kilocytes reacted positively both by ISH and immunohistochemical methods. Nested PCR is not a very complicated technique, and the detection rate is higher than that of commonly used pathological techniques. These results suggest that nested PCR will be a useful test for HPV routine pathological diagnosis.

Base Sequence↗