Rabbit polyclonal primary
NAPSIN A Antibody (ER1901-84)
Recombinant protein within human napsin a aa 44-183.
Human lung tissue, 293T, human lung cancer tissue, human kidney tissue.
Store at +4C after thawing. Aliquot store at -20C. Avoid repeated freeze / thaw cycles.
1*PBS (pH7.4), 0.2% BSA, 50% Glycerol. Preservative: 0.05% Sodium Azide.
Protein affinity purified.
Predicted band size 11/30/45 kDa.
Asp 4 antibody; ASP4 antibody; Aspartyl protease 4 antibody; KAP antibody; Kdap antibody; Kidney derived aspartic protease like protein antibody; NAP1 antibody; NAPA antibody; Napsa antibody; NAPSA_HUMAN antibody; Napsin 1 antibody; napsin A aspartic peptidase antibody; Napsin A precursor antibody; Napsin-1 antibody; Napsin-A antibody; Pronapsin A antibody; SNAPA antibody; TA01/TA02 antibody
Belongs to the peptidase A1 family.
Expressed predominantly in adult lung (type II pneumocytes) and kidney and in fetal lung. Low levels in adult spleen and very low levels in peripheral blood leukocytes.
Napsin A is an asparatic protease with a molecular weight of approximately 38 kDa, expressed in type-II pneumocytes and is involved in the N- and C-terminal processing of proSP-B in type-II pneumocytes. TAO2 has been shown to be identical with Napsin A. There is also a Napsin B gene which is transcribed exclusively in cells related to the immune system but lacks a stop codon and may represent a transcribed pseudogene. It is expressed in the cytoplasm and is strongly positive in up to 80% of primary lung adenocarcinomas by immunohistochemistry. Poorly differentiated cancers do not stain as well as those that are well-differentiated. Squamous cell carcinomas and small cell carcinomas of the lung have been negative for napsin A. However, 10% of renal cell carcinomas and thyroid carcinomas are also positive. Renal and thyroid cancers may give false positive results, most likely because of the presence of intrinsic biotin, which can be detected on negative controls. Less than 5% of assorted adenocarcinomas, including those from the breast, pancreas, biliary tract, and colon stain with napsin A: expression, when present in breast and colonic adenocarcinomas, appears to be granular, unlike that in the lung.