Tissue factor detection in mouse tissues by western blotting using commercial antibodies

Tissue factor (TF) is a receptor for factor (F)VII/FVIIa and is essential for hemostasis. TF is expressed in a tissue-specific manner, with differing TF levels across tissues. TF expression is increased in a variety of diseases, so accurate measurement of TF protein levels is important.

The goal of this study was to evaluate the ability of 4 commercial antibodies to measure TF in various mouse tissues using western blotting.

We used the goat anti-mouse TF polyclonal antibody AF3178 (R&D Systems), the rabbit anti-mouse TF monoclonal antibody ab189483 (Abcam), the rabbit anti-mouse TF monoclonal antibody 44861 (Cell Signaling Technology), and the mouse anti-mouse TF monoclonal antibody H9 (Santa Cruz Biotechnology) to measure TF in the mouse pancreatic cancer cell line KPC2 wild-type and KPC2 TF knockout cell lysates, as well as various tissues from wild-type and low TF mice (no mouse TF expression) using western blotting.

All 4 antibodies detected TF in KPC2 wild-type cells but not in KPC2 TF knockout cells. All 4 antibodies detected TF in the brain, lung, heart, kidney, and spleen. The relative amounts of TF in these tissues were consistent with the tissue distribution of TF mRNA reported in previous studies. Nonspecific bands were detected in various tissues with the different antibodies.

Our study demonstrated that the Abcam and Cell Signaling Technology anti-mouse TF monoclonal antibodies gave the strongest signal for TF in mouse tissues. However, researchers should be aware that all 4 antibodies also detect nonspecific bands in some tissues.