The bead-based NexaTag Canine CD40 Ligand/TNFSF5 qIPCR ELISA Kit merges the specificity of sandwich-based ELISA, the sensitivity of real-time PCR, and the easy manipulation of microspheres to detect even the lowest levels of CD40 Ligand/TNFSF5 in serum, plasma, and cell culture supernatant samples.