TTF-1 + p40 (cRM)

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Thyroid transcription factor-1 (TTF-1) is a member of the NKX2 family of homeodomain transcription factors. Studies have shown that TTF-1 is expressed in epithelial cells of the thyroid gland and lung. TTF-1 has been shown to be a sensitive (62-80%) and specific marker (89-95%) in the majority of primary lung
adenocarcinomas (ADC) (1-7). When combined in a cocktail with a rabbit polyclonal p40, TTF-1 was reported to demonstrate 77% sensitivity for lung ADC, and 100% specificity vs. lung squamous cell carcinoma (SCC) (7).

p40 has been shown to be selectively expressed in lung SCC, offering the potential for increased specificity compared to p63 (8-9). Mouse monoclonal p40 [BC28] recognizes an epitope unique to p40 and has been shown to be sensitive, staining 93% (99/107) of cases of lung SCC and specific, staining 0.8% (1/121) of cases of lung ADC (10).

Chimeric rabbit monoclonal rabbit p40 [BC28/cRM] was designed to replicate the sensitivity and specificity of mouse monoclonal p40 [BC28] as a rabbit antibody that would be suitable for a double-stain procedure. The variable regions of p40 [BC28], which define the binding sensitivity and specificity of the antibody, were cloned and fused with the constant regions of rabbit IgG to provide the chimeric rabbit monoclonal.

p40 [BC28/cRM]. In a side-by-side study on the same tissues, mouse monoclonal p40 [BC28] and chimeric rabbit monoclonal p40 [BC28/cRM] exhibited identical sensitivity (8/10) for lung SCC and specificity versus lung ADC (0/12). PATENT PENDING.


Mouse Monoclonal, Rabbit Monoclonal


8G7G3/1, BC28/cRM


IgG, IgG1


Amino Acids 5-17 of p40, TTF-1



Positive Control

Lung adenocarcinoma (TTF-1), Lung SCC (p40)

Species Reactivity


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cell carcinoma. Mod Pathol. 2012 Mar; 25(3):405-15.

9. Hibi K, et al. AIS is an oncogene amplified in squamous cell carcinoma. Proc Natl
Acad Sci U S A. 2000 May 9; 97(10):5462-7.

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developed, mouse monoclonal p40 (BC28) antibody in lung, bladder, skin, breast,
prostate, and head and neck cancers. Arch Pathol Lab Med. 2014 Oct;138(10):1358-64.

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biopsies or cellblocks for typing non-small cell lung cancer: a novel two-hit, sparingmaterial
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