W87 - A Versatile New Monoclonal Antibody for Elucidating Human TMPRSS2 Expression and Function

Transmembrane Serine Protease 2 (TMPRSS2) is a cellular type II transmembrane serine protease expressed in human respiratory epithelium that cleaves and activates the SARS-CoV-2 spike protein. This activation is essential for viral infectivity. Blocking TMPRSS2 activity with protease inhibitors inhibits SARS-CoV-2 infection. TMPRSS2 is overexpressed in human cancers and promotes metastasis by cleavage of extracellular matrix proteins. In prostate cancer, increased expression of TMPRSS2 is associated with progression, invasion and metastasis. However, the normal physiological role for TMPRSS2 remains poorly understood.

Methods for inhibiting TMPRSS2 are urgently needed to further understand TMPRSS2 function and for potential therapy. Current tools for the study of TMPRSS2 function are limited to protease inhibitors which have low specificity for individual proteases, limiting their use for therapeutic approaches and functional studies of TMPRSS2. 

We developed a mouse monoclonal antibody against human TMPRSS2 (clone S20014A) and performed specificity testing by flow cytometry, immunofluorescence and in functional assays. Clone S20014A specifically binds human TMPRSS2 and shows positive signal by flow cytometry in on human colon and prostate carcinoma cells and on human platelets.  Clone S20014A detects expression of TMPRSS2 in human colon tissue sections by immunofluorescence.

Furthermore, this antibody can inhibit the protease activity of recombinant TMPRSS2 similar to the broad-spectrum protease inhibitor Nafamostat. Clone S20014A blocks invasion of the human colon carcinoma cell line Caco-2, with potency similar to Nafamostat.

In conclusion, anti-human TMPRSS2 (clone S20014A) is a valuable tool for the study of TMPRSS2 function and expression in human cells.