Tumor necrosis factor alpha has been shown to be important in the cellular response to chronic heart failure, with signaling taking place through the receptor isotypes TNFR1 and TNFR2. We at Novus Biologicals have a large number of TNF-related antibodies in our database. Many of today’s studies are based on information gained by Defer et al. in 2007.
The study set out to further define the TNFR1/2 signaling pathways in rat cardiac myocytes, and used a range of antibody preparations. These included phosphorylated rabbit polyclonal antibodies (including phospho-p44/p42, phospho-MSK1 and phospho-cPLA2); monoclonal anti-cPLA2 antibodies; rabbit polyclonal actin antibody; Peroxidase-conjugated goat anti-rabbit and anti-mouse IgG, and FITC-conjugated donkey anti-mouse antibody.
Cardiac myocytes were isolated from treated and control rats, and a range of assays were performed. These included measurement of [Ca2+] levels and cell fractional shortening; Measurement of ROS production and measurement of cell survival using TNFR1 or TNFR2 antibodies +/- TNFα.
Immunoblot analysis was performed to visualize peroxidase activity, using conjugated goat anti-rabbit or anti-mouse antibodies. IHC analysis of myocytes was also performed, incubating first with mouse monoclonal cPLA2 antibodies, and then FITC-conjugated donkey anti-mouse antibodies. Laser image scanning was also performed of TNFα, +/- anti-TNFR1 or TNFR2 Mab antibodies.
The results showed that TNFR1 activated production of reactive oxygen species, and had both positive and negative effects on calcium handling, fractional shortening and cell death. In contrast, TNFR2 played a cell-survival role by inhibiting ROS production and apoptosis.
Treatment with neutralizing TNFR1 antibodies revealed a positive TNFR2 effect on cell fractional shortening and [Ca2+] handling. There was a close interplay between the TNFR1 and TNFR2 pathways. Although TNFR1 signaling predominated, it was under the mediation of TNFR2, which played a limiting role.
Novus Biologicals offers many TNFR reagents for your research needs including: