Anti-CD8 (SP57) rabbit monoclonal antibody is a useful tool for detecting Toxoplasma gondii on formalin-fixed, paraffin-embedded tissue sections

In a retrospective multicenter study, 102 formalin-fixed paraffin-embedded (FFPE) tissue specimens with histopathology results were tested. Two 4- to 5-μm FFPE tissue sections from each specimen were digested with proteinase K, followed by automated nucleic acid extraction. Multiple real-time quantitative PCR (qPCR) assays targeting the internal transcribed spacer 2 (ITS2) region of ribosomal DNA, using fluorescently labeled primers, was performed to identify clinically important genera and species of Aspergillus , Fusarium , Scedosporium , and the Mucormycetes . The molecular identification was correlated with results from histological examination. One of the main findings of our study was the high sensitivity of the automated DNA extraction method, which was estimated to be 94%. The qPCR procedure that was evaluated identified a range of fungal genera/species, including Aspergillus fumigatus , Aspergillus flavus , Aspergillus terreus , Aspergillus niger , Fusarium oxysporum , Fusarium solani , Scedosporium apiospermum , Rhizopus oryzae , Rhizopus microsporus , Mucor spp., and Syncephalastrum . Fusarium oxysporum and F. solani DNA was amplified from five specimens from patients initially diagnosed by histopathology as having aspergillosis. Aspergillus flavus , S. apiospermum , and Syncephalastrum were detected from histopathological mucormycosis samples. In addition, examination of four samples from patients suspected of having concomitant aspergillosis and mucormycosis infections resulted in the identification of two A. flavus isolates, one Mucor isolate, and only one sample having both R. oryzae and A. flavus . Our results indicate that histopathological features of molds may be easily confused in tissue sections. The qPCR assay used in this study is a reliable tool for the rapid and accurate identification of fungal pathogens to the genus and species levels directly from FFPE tissues.

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Quantitative radioimmunohistochemical measurements of p185(erbB-2) in frozen tissue sections.

Journal of Histochemistry & Cytochemistry ◽

10.1177/44.11.8918900 ◽

1996 ◽

Vol 44 (11) ◽

pp. 1251-1259 ◽

Cited By ~ 12

Author(s):

J R Reeves ◽

J J Going ◽

G Smith ◽

T G Cooke ◽

B W Ozanne ◽

...

Keyword(s):

Tumor Biology ◽

Breast Carcinomas ◽

Tissue Sections ◽

Biopsy Specimens ◽

Formalin Fixed Paraffin ◽

Formalin Fixed Paraffin Embedded ◽

Interstudy Variability ◽

High Degree ◽

The Relationship ◽

Formalin Fixed

The relationship between expression of the c-erbB-2 proto-oncogene and the biology of breast cancer has been investigated widely, most studies using immunohistochemistry in formalin-fixed, paraffin-embedded tissues. This technique is at best semiquantitative and there is a high degree of interstudy variability because of its subjective nature and poor methodological standardization. The relationship between the levels of expression and biology can be examined thoroughly only with an accurately quantitative technique. We have developed a radioimmunohistochemical assay to measure p185(erbB-2) in tissue biopsy specimens. The method involves incubating frozen sections with 125I-labeled monoclonal antibody, microautoradiograpy, and grain counting with image analysis. Sections of cell pellets with known c-erbB-2 levels are processed with each batch of samples as internal calibration standards. We have quantified c-erbB-2 expression in 60 breast carcinomas and compared the results with conventional immunohistochemistry. Radioimmunohistochemistry measured receptor levels throughout the range of expression in breast carcinomas, whereas conventional immunohistochemistry detected the protein only in the highest expressing tumors. The quantitative, objective data produced by radioimmunohistochemistry allow a more thorough evaluation of the relationship between c-erbB-2 expression and tumor biology. This technique may have applications in other fields where quantitative data is required and relevant monoclonal antibodies are available.

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