Analysis of apoptosis induced by Caprine Herpesvirus 1 in vitro.

It is known that Caprine Herpesvirus 1 (CpHV-1) causes apoptosis in mitogen-stimulated as well as not stimulated caprine peripheral blood mononuclear cells (PBMC). Initial experiments in Madin Darby bovine kidney (MDBK) cells revealed that CpHV-1 infection induced apoptotic features like chromatin condensation and DNA laddering. Thus, to characterize in more detail this apoptotic process, activation of caspase-8, -9 and -3 in MDBK cells CpHV-1 infected was investigated and demonstrated. In addition, CpHV-1 infection resulted in disruption of mitochondrial membrane potential, cytochrome c release and alterations in the pro- and anti-apoptotic proteins of Bcl-2 family. Proteolytic cleavage of poly(ADP-ribose) polymerases (PARP), confirming the activation of downstream caspases, was also observed. Our data indicated that a "cross-talk" between the death-receptor (extrinsic) pathway and the mitochondrial (intrinsic) pathway occurred in CpHV-1-induced apoptosis in vitro.