TTF-1 [SPT24]

transcription factor-1 (TTF-1) is a 38 kDa constituent of the NKX2 family of homeodomain transcription factors. TTF-1 is predominantly identified in primary lung adenocarcinomas and small cell carcinomas. TTF-1 is highly beneficial in lung malignancies when utilized in conjunction with Desmoglein 3, p40, and Napsin A antibodies. Monoclonal antibodies 8G7G3/1 and SPT24, commercially available for thyroid transcription factor-1 (TTF-1), exhibit varying sensitivities in lung adenocarcinomas (LADC) and lung squamous cell carcinomas (SqCC). A study by Masai et al. revealed that SPT24 had much greater sensitivity than 8G7G3/1 in LADC, with rates of 72.4% and 65.4%, respectively. The findings indicated that SPT24 exhibited a greater staining percentage in lung SqCC (16.8% compared to 1%). The increased sensitivity of SPT24 in lung squamous cell carcinoma is significantly affected by various detection techniques. SPT24 can produce greater sensitivity for LADC compared to lung SqCC, relative to 8G7G3/1, while maintaining specificity by the application of a cut-off value and appropriate antibody titer. In an internal research, SPT24 was titrated to attain negative staining in normal liver, with no cytoplasmic staining detected. A cut-off threshold of ≥10% of tumor cells exhibiting TTF-1 positivity with a staining intensity of ≥ 1+ was employed to ascertain TTF-1 positive instances. Employing this methodology, SPT24 shown significant sensitivity for LADC (53/60, 88%), in contrast to 8G7G3/1 (38/60, 63%), although both clones exhibited comparable specificity against lung SqCC (2/137, 1.5%). The utilization of lung SqCC-specific markers, including Desmoglein 3 and p40, may discern TTF-1 positive instances of squamous cell genesis. The application of Napsin A may validate lung adenocarcinoma, as the co-expression of Napsin A and TTF-1 in lung malignancies has demonstrated more pulmonary specificity than either marker employed independently. In contrast to clone 8G7G3/1, clone SPT24 has not exhibited any cytoplasmic staining in lung tumors.

Specifications

Intended Use	RUO
Format	Concentrate, ONCORE Pro, Predilute, Q Series, UltraLine
Volume	0.1 ml, 1.0 ml, 20 ml, 6.0 ml, 60 Tests, 7 ml
Source	Mouse Monoclonal
Clone	SPT24
Isotype	IgG1/kappa
Antigen	TTF-1
Localization	Nuclear
Positive Control	Lung adenocarcinoma