Thermo Fisher Scientific Napsin-A Monoclonal Antibody (ZM11), MonoMab

Applications

Tested Dilution

Publications

Immunohistochemistry (Paraffin) (IHC (P))

Ready-to-use 150-200 µL

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Product Specifications

Species Reactivity

Human

Host/Isotype

Mouse / IgG1, kappa

Class

Monoclonal

Type

Antibody

Clone

ZM11

Immunogen

Recombinant fragment of human napsin protein

Conjugate

Unconjugated Unconjugated Unconjugated

Form

Liquid

Purification

Protein A

Storage buffer

tris with NP-40, BSA

Contains

<0.1% sodium azide

Storage conditions

4° C

Shipping conditions

Wet ice

Product Specific Information

This product is diluted and in a ready-to-use formulation.

A recommended positive control tissue for this product is Lung adenocarcinoma, however positive controls are not limited to this tissue type.

The primary antibody is intended for laboratory professional use in the detection of the corresponding protein in formalin-fixed, paraffin-embedded tissue stained in manual qualitative immunohistochemistry (IHC) testing. This antibody is intended to be used after the primary diagnosis of tumor has been made by conventional histopathology using non-immunological histochemical stains.

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.

Antibody is used with formalin-fixed and paraffin-embedded sections. Pretreatment of deparaffinized tissue with heat-induced epitope retrieval or enzymatic retrieval is recommended. In general, immunohistochemical (IHC) staining techniques allow for the visualization of antigens via the sequential application of a specific antibody to the antigen (primary antibody), a secondary antibody to the primary antibody (link antibody), an enzyme complex and a chromogenic substrate with interposed washing steps. The enzymatic activation of the chromogen results in a visible reaction product at the antigen site. Results are interpreted using a light microscope and aid in the differential diagnosis of pathophysiological processes, which may or may not be associated with a particular antigen.

A positive tissue control must be run with every staining procedure performed. This tissue may contain both positive and negative staining cells or tissue components and serve as both the positive and negative control tissue. External Positive control materials should be fresh autopsy/biopsy/surgical specimens fixed, processed and embedded as soon as possible in the same manner as the patient sample (s). Positive tissue controls are indicative of correctly prepared tissues and proper staining methods. The tissues used for the external positive control materials should be selected from the patient specimens with well-characterized low levels of the positive target activity that gives weak positive staining. The low level of positivity for external positive controls is designed to ensure detection of subtle changes in the primary antibody sensitivity from instability or problems with the staining methodology. A tissue with weak positive staining is more suitable for optimal quality control and for detecting minor levels of reagent degradation.

Internal or external negative control tissue may be used depending on the guidelines and policies that govern the organization to which the end user belongs to. The variety of cell types present in many tissue sections offers internal negative control sites, but this should be verified by the user. The components that do not stain should demonstrate the absence of specific staining, and provide an indication of non-specific background staining. If specific staining occurs in the negative tissue control sites, results with the patient specimens must be considered invalid.

Target Information

Napsin 1 is an aspartic protease that is generally expressed in the lung, but also present in kidney and in metastatic carcinomas throughout the body. Napsin 1 processes surfactant protein B in healthy pulmonary and renal tissues, but is abnormally regulated when carcinogenesis occurs. Thus, many researchers have found napsin evaluation to be useful in identifying several cancers, and differentiating primary tumors from metastases. When combined with thyroid transcription factor analysis, napsin can be used as a specific biomarker for differentiation of carcinoma types. Napsin has also been associated with pulmonary alveolar proteinosis as well as in protein catabolism in renal tubules.

For Research Use Only. Not for use in diagnostic procedures. Not for resale without express authorization.