Bcl2-associated athanogene 3 (BAG3) is a 575 amino acid protein that is found predominantly in the heart, skeletal muscle, and many cancers. Deletions and truncations in BAG3 that result in haplo-insufficiency have been associated with the development of dilated cardiomyopathy. BAG3 is a stress-induced molecular co-chaperone that functions to regulate cellular protein homeostasis and cell survival via Chaperone-Assisted Selective Autophagy (CASA). CASA and specifically BAG3 may represent a novel host defense mechanism, whereby BAG3 may dampen egress of several hemorrhagic fever viruses by interacting and interfering with the budding function of viral PPxY-containing matrix proteins. BCL2-associated athanogene (BAG)-3 is viewed as a platform that would physically and functionally link distinct classes of molecular chaperones of the heat shock protein (HSP) family for the stabilization and clearance of damaged proteins. The HSPB8-BAG3 connection in mounting of an efficient stress response, which may be involved in BAG3-related human diseases. Both Bcl-2-associated athanogene 3 (BAG3) and tumor necrosis factor-related apopt-osis inducing ligand (TRAIL) involved in apoptosis.