Human TMPRSS11D Stable Cell Line - HEK293T

TMPRSS11D, also known as HAT (Human Airway Trypsin-like protease) or ASP (Adrenal Secretory Serine Protease), is a type II transmembrane serine protease encoded by the TMPRSS11D gene located on chromosome 4q13.2. This enzyme belongs to the trypsin-like serine protease family and shares 29–38% sequence identity in the catalytic region with human hepsin, enteropeptidase, acrosin, and mast cell tryptase, while its non-catalytic region shows little similarity to other known proteins. TMPRSS11D is normally expressed in the submucosal serous glands and released onto mucous membranes, where it contributes to the host defense system. The protease has drawn significant attention for its ability to proteolytically cleave and activate viral envelope glycoproteins, thereby facilitating viral entry into host cells. It has been specifically implicated in the activation of the SARS-CoV-2 spike protein, as well as hemagglutinin cleavage in influenza A viruses such as H9N2. The Human TMPRSS11D Stable Cell Line - HEK293T is generated by stably integrating the human TMPRSS11D into the HEK293T genome, enabling consistent and inducible or constitutive expression of the functional protease on the cell surface. This stable line eliminates the need for repeated transient transfections and provides a reproducible and scalable platform for downstream experiments.

This cell line serves as a practical tool for a range of research applications. It is particularly useful for studying the mechanisms of viral entry, especially for coronaviruses and influenza viruses that rely on host proteases for spike or hemagglutinin priming. Researchers can use this line to screen for protease inhibitors that block TMPRSS11D activity, which may have therapeutic potential against respiratory viral infections. It also supports investigations into the broader biological functions of TMPRSS11D, including its role in airway inflammation, fibrosis, and cancer progression. For example, studies have shown that TMPRSS11D can stimulate IL-8 synthesis in airway epithelial cells via PAR2 activation and that high TMPRSS11D expression correlates with poor prognosis in non-small cell lung cancer. Additionally, the stable line can be employed in cell-cell fusion assays, pseudovirus entry assays, and co-culture experiments to evaluate the interplay between TMPRSS11D and viral glycoproteins or other host factors.