The tuftelin is a secreted protein in the adamantine matrix in developing during the enamel formation. Its function continues unclarified, although it plays a role in the biomineralization of the ...dental organ. With the present studio the location was identified in the different structures of dental germs from human fetuses, according to the results it was observed the expression in the pre-secretor stage being observed in the cytoplasm of ameloblasts, stellate reticulum, dental papilla, also in the intermediate stratum; in the secretor it was mainly identified in the amelodentinal junction and in the outer surface of enamel, observing a marked expression of the protein in the basal portion of the odontoblastic process, but not in the extracellular matrix of the dentine. According to the results obtained it can be considered that its expression occurs in both amelogenesis and odontegenesis in unmineralized tissues. KEY WORDS: Tuftelin; Immunohistochemistry; Amelogenesis. La tuftelina es una proteina secretada en la matriz adamantina en desarrollo durante la formacion del esmalte. Su funcion continua sin esclarecerse, aunque se presume que juega un papel importante en la biomineralizacion de esmalte y dentina, asi como en el desarrollo del organo dental. Con el presente estudio se identifico su localizacion en las diferentes estructuras de germenes dentales de fetos humanos, conforme a los resultados se observo su expresion en el estadio pre-secretor observandose en el citoplasma de los ameloblastos, reticulo estrellado, papila dental, asi como en el estrato intermedio; en el secretor se identifico principalmente en la union amelodentinaria, y en la superficie externa del esmalte, observando una marcada expresion de la proteina en la porcion basal del proceso odontoblastico, pero no en la matriz extracelular de la dentina. De acuerdo a los resultados obtenidos se puede considerar que su expresion se presenta tanto en la amelogenesis, como en la odontogenesis en tejidos sin mineralizar, PALABRAS CLAVE: tuftelina; inmunohistoquimica; amelogenesis.
Different clones, protocol conditions, instruments, and scoring/readout methods may pose challenges in introducing different PD-L1 assays for immunotherapy. The diagnostic accuracy of using different ...PD-L1 assays interchangeably for various purposes is unknown. The primary objective of this meta-analysis was to address PD-L1 assay interchangeability based on assay diagnostic accuracy for established clinical uses/purposes. A systematic search of the MEDLINE database using PubMed platform was conducted using "PD-L1" as a search term for 01/01/2015 to 31/08/2018, with limitations "English" and "human". 2,515 abstracts were reviewed to select for original contributions only. 57 studies on comparison of two or more PD-L1 assays were fully reviewed. 22 publications were selected for meta-analysis. Additional data were requested from authors of 20/22 studies in order to enable the meta-analysis. Modified GRADE and QUADAS-2 criteria were used for grading published evidence and designing data abstraction templates for extraction by reviewers. PRISMA was used to guide reporting of systematic review and meta-analysis and STARD 2015 for reporting diagnostic accuracy study. CLSI EP12-A2 was used to guide test comparisons. Data were pooled using random-effects model. The main outcome measure was diagnostic accuracy of various PD-L1 assays. The 22 included studies provided 376 2×2 contingency tables for analyses. Results of our study suggest that, when the testing laboratory is not able to use an Food and Drug Administration-approved companion diagnostic(s) for PD-L1 assessment for its specific clinical purpose(s), it is better to develop a properly validated laboratory developed test for the same purpose(s) as the original PD-L1 Food and Drug Administration-approved immunohistochemistry companion diagnostic, than to replace the original PD-L1 Food and Drug Administration-approved immunohistochemistry companion diagnostic with a another PD-L1 Food and Drug Administration-approved companion diagnostic that was developed for a different purpose.
Antigen Retrieval Immunohistochemistry Shi, Shan-Rong; Shi, Yan; Taylor, Clive R.
Journal of Histochemistry & Cytochemistry,
01/2011, Letnik:
59, Številka:
1
Book Review, Journal Article
Recenzirano
Odprti dostop
As a review for the 20th anniversary of publishing the antigen retrieval (AR) technique in this journal, the authors intend briefly to summarize developments in AR-immunohistochemistry (IHC)–based ...research and diagnostics, with particular emphasis on current challenges and future research directions. Over the past 20 years, the efforts of many different investigators have coalesced in extending the AR approach to all areas of anatomic pathology diagnosis and research and further have led to AR-based protein extraction techniques and tissue-based proteomics. As a result, formalin-fixed paraffin-embedded (FFPE) archival tissue collections are now seen as a literal treasure of materials for clinical and translational research to an extent unimaginable just two decades ago. Further research in AR-IHC is likely to focus on tissue proteomics, developing a more efficient protocol for protein extraction from FFPE tissue based on the AR principle, and combining the proteomics approach with AR-IHC to establish a practical, sophisticated platform for identifying and using biomarkers in personalized medicine.
Purpose To update key recommendations of the American Society of Clinical Oncology/College of American Pathologists human epidermal growth factor receptor 2 (HER2) testing in breast cancer guideline. ...Methods Based on the signals approach, an Expert Panel reviewed published literature and research survey results on the observed frequency of less common in situ hybridization (ISH) patterns to update the recommendations. Recommendations Two recommendations addressed via correspondence in 2015 are included. First, immunohistochemistry (IHC) 2+ is defined as invasive breast cancer with weak to moderate complete membrane staining observed in > 10% of tumor cells. Second, if the initial HER2 test result in a core needle biopsy specimen of a primary breast cancer is negative, a new HER2 test may (not "must") be ordered on the excision specimen based on specific clinical criteria. The HER2 testing algorithm for breast cancer is updated to address the recommended work-up for less common clinical scenarios (approximately 5% of cases) observed when using a dual-probe ISH assay. These scenarios are described as ISH group 2 ( HER2/chromosome enumeration probe 17 CEP17 ratio ≥ 2.0; average HER2 copy number < 4.0 signals per cell), ISH group 3 ( HER2/CEP17 ratio < 2.0; average HER2 copy number ≥ 6.0 signals per cell), and ISH group 4 ( HER2/CEP17 ratio < 2.0; average HER2 copy number ≥ 4.0 and < 6.0 signals per cell). The diagnostic approach includes more rigorous interpretation criteria for ISH and requires concomitant IHC review for dual-probe ISH groups 2 to 4 to arrive at the most accurate HER2 status designation (positive or negative) based on combined interpretation of the ISH and IHC assays. The Expert Panel recommends that laboratories using single-probe ISH assays include concomitant IHC review as part of the interpretation of all single-probe ISH assay results. Find additional information at www.asco.org/breast-cancer-guidelines .
Once focused mainly on the characterization of neoplasms, immunohistochemistry (IHC) today is used in the investigation of a broad range of disease processes with applications in diagnosis, ...prognostication, therapeutic decisions to tailor treatment to an individual patient, and investigations into the pathogenesis of disease. This review addresses the technical aspects of immunohistochemistry (and, to a lesser extent, immunocytochemistry) with attention to the antigen-antibody reaction, optimal fixation techniques, tissue processing considerations, antigen retrieval methods, detection systems, selection and use of an autostainer, standardization and validation of IHC tests, preparation of proper tissue and reagent controls, tissue microarrays and other high-throughput systems, quality assurance/quality control measures, interpretation of the IHC reaction, and reporting of results. It is now more important than ever, with these sophisticated applications, to standardize the entire IHC process from tissue collection through interpretation and reporting to minimize variability among laboratories and to facilitate quantification and interlaboratory comparison of IHC results.
To update key recommendations of the American Society of Clinical Oncology/College of American Pathologists estrogen (ER) and progesterone receptor (PgR) testing in breast cancer guideline.
A ...multidisciplinary international Expert Panel was convened to update the clinical practice guideline recommendations informed by a systematic review of the medical literature.
The Expert Panel continues to recommend ER testing of invasive breast cancers by validated immunohistochemistry as the standard for predicting which patients may benefit from endocrine therapy, and no other assays are recommended for this purpose. Breast cancer samples with 1% to 100% of tumor nuclei positive should be interpreted as ER positive. However, the Expert Panel acknowledges that there are limited data on endocrine therapy benefit for cancers with 1% to 10% of cells staining ER positive. Samples with these results should be reported using a new reporting category, ER Low Positive, with a recommended comment. A sample is considered ER negative if < 1% or 0% of tumor cell nuclei are immunoreactive. Additional strategies recommended to promote optimal performance, interpretation, and reporting of cases with an initial low to no ER staining result include establishing a laboratory-specific standard operating procedure describing additional steps used by the laboratory to confirm/adjudicate results. The status of controls should be reported for cases with 0% to 10% staining. Similar principles apply to PgR testing, which is used primarily for prognostic purposes in the setting of an ER-positive cancer. Testing of ductal carcinoma in situ (DCIS) for ER is recommended to determine potential benefit of endocrine therapies to reduce risk of future breast cancer, while testing DCIS for PgR is considered optional. Additional information can be found at www.asco.org/breast-cancer-guidelines.
Abstract
Introduction/Objective
INSM1 is a transcription factor protein which is increasingly used as an immunohistochemical marker for neuroendocrine differentiation.
Methods/Case Report
To ...determine the prevalence of INSM1 expression in tumors and its expression pattern in normal tissues, tissue microarrays containing 14,908 samples from 117 different tumor types/subtypes as well as 76 different normal tissues were analyzed by immunohistochemistry.
Results (if a Case Study enter NA)
INSM1 was positive in 89.2% of 471 neuroendocrine neoplasms (NEN) and in 3.5% of 11,815 non-neuroendocrine neoplasms that were successfully analyzed. INSM1 positivity occurred in 59 non- neuroendocrine tumor entities, of which 15 entities contained at least one strongly positive case. Comparison with synaptophysin and chromogranin A revealed that in NEN, synaptophysin showed the highest sensitivity (93.3%), followed by INSM1 (89.2%) and chromogranin A (87.5%). In neuroendocrine carcinomas (NEC), sensitivity was highest for INSM1 (88.0%), followed by synaptophysin (86.5%) and chromogranin A (66.4%). The additional use of INSM1 increased the sensitivity for detecting neuroendocrine differentiation in NEN from 88.2% (synaptophysin and chromogranin A) to 91.2% (synaptophysin, chromogranin A and INSM1).
Conclusion
Our study shows that INSM1 is a useful additional marker for neuroendocrine differentiation that shows a particularly high sensitivity in NEC. The additional use of INSM1 results in a higher sensitivity for the identification of a neuroendocrine differentiation than what can be obtained by using only synaptophysin and chromogranin A.
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