Bio-Plex Pro cell-signaling assays are designed for detecting phosphorylated and total proteins involved in key intracellular signaling pathways. The 34 magnetic bead–based immunoassays (23 phosphoprotein and 11 total protein targets) have been reformulated and optimized to provide sensitivity, specificity, and good performance. They are available in singleplex sets and custom premixed all-in-one kit formats. Bio-Plex Pro cell-signaling assays can be used with lysates derived from adherent cells, suspension cells, or tissue samples.