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Napsin A (EP205) Rabbit Monoclonal Primary Antibody


biological source


Quality Level



antibody form

culture supernatant

antibody product type

primary antibodies


EP205, monoclonal


(For In Vitro Diagnostic Use in Select Regions (See Chart))


buffered aqueous solution

species reactivity



vial of 0.1 mL concentrate (352R-14)
vial of 0.5 mL concentrate (352R-15)
bottle of 1.0 mL predilute (352R-17)
vial of 1.0 mL concentrate (352R-16)
bottle of 7.0 mL predilute (352R-18)


Cell Marque


immunohistochemistry (formalin-fixed, paraffin-embedded sections): 1:100-1:500




lung adenocarcinoma, renal cell carcinoma

shipped in

wet ice

storage temp.




General description

Napsin is a pepsin-like aspartic proteinase, in the A1 clan of the AA clade of proteinases. There are two closely related napsins, napsin A and napsin B. Napsin A is expressed as a single chain protein with the molecular weight of approximately 38 kDa. Immunohistochemical studies revealed high expression levels of napsin A in human lung and kidney but low expression in spleen. Napsin A is expressed in type II pneumocytes and in adenocarcinomas of lung. The high specificity expression of napsin A in adenocarcinomas of lung is useful to distinguish primary lung adenocarcinomas from adenocarcinomas of other organs.1-5







Napsin A Positive Control Slides, Product No. 352S, are available for immunohistochemistry (formalin-fixed, paraffin-embedded sections).

Physical form

Solution in Tris Buffer, pH 7.3-7.7, with 1% BSA and <0.1% Sodium Azide.

Preparation Note

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Other Notes

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Legal Information

Cell Marque is a trademark of Sigma-Aldrich Co. LLC

Certificate of Analysis

Certificate of Origin

Kentaro Inamura et al.
The American journal of surgical pathology, 29(5), 660-665 (2005-04-16)
Primary pulmonary adenocarcinomas with enteric differentiation (PAED) are mainly composed of tall-columnar cells that show similarity to intestinal epithelia and colorectal carcinomas. In this study, we analyzed the immunostaining profiles of 7 PAEDs in comparison with 14 metastatic colorectal carcinomas
Jaishree Jagirdar
Archives of pathology & laboratory medicine, 132(3), 384-396 (2008-03-06)
Immunohistochemistry is a very valuable and often used tool in the differential diagnosis of lung carcinomas whether primary or secondary to the lung. The most useful application is in distinguishing primary lung tumors from metastatic tumors to the lung from
Jiqing Ye et al.
Applied immunohistochemistry & molecular morphology : AIMM, 19(4), 313-317 (2011-04-06)
Differentiation of primary from metastatic adenocarcinoma in the lung can be challenging, and it demands sensitive and specific biomarkers, especially when the tissue for diagnosis is limited. Thyroid transcription factor-1 (TTF-1) has been considered a reliable marker for adenocarcinoma of
Annika Dejmek et al.
Diagnostic cytopathology, 35(8), 493-497 (2007-07-20)
The purpose of this study was to test napsin A as a diagnostic marker of metastatic lung adenocarcinoma in pleural effusions, and to compare its performance with TTF-1. Napsin A and TTF-1 reactivities were determined immunohistochemically on formalin-fixed paraffin embedded
Justin A Bishop et al.
Human pathology, 41(1), 20-25 (2009-09-11)
Recent advances in the treatment of pulmonary adenocarcinoma have increased the need for accurate typing of non-small cell carcinomas. Immunohistochemistry for thyroid transcription factor-1 is widely used in the diagnosis of pulmonary adenocarcinomas because it marks approximately 75% of lung

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