Overproduction of the Pro-Apoptotic Molecule, Programmed Cell Death 5, in Toxoplasma gondii Leads to Increased Apoptosis of Host Macrophages

J Vet Med Sci. 2009 Sep;71(9):1183-9

Overproduction of the Pro-Apoptotic Molecule, Programmed Cell Death 5, in Toxoplasma gondii Leads to Increased Apoptosis of Host Macrophages

Bannai H, Nishikawa Y, Ibrahim HM, Yamada K, Kawase O, Watanabe J, Sugimoto C, Xuan X.

National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine.

We established a recombinant strain of Toxoplasma gondii that overexpressed programmed cell death 5 (TgPDCD5), in order to evaluate the role of endogenous TgPDCD5 in macrophage apoptosis during T. gondii infection. Immunofluorescence microscopy revealed that overproduced TgPDCD5 with a hemagglutinin tag was localized in the cytosol, which was consistent with the localization of endogenous TgPDCD5. The induced TgPDCD5-HA was recognized as an additional band by Western blot analysis, indicating successful overexpression of TgPDCD5. Secretion and release of TgPDCD5 by the parasite was also up-regulated in a time-dependent manner, which reflected its overproduction. Apoptosis due to parasite infection and interferon-gamma treatment was significantly up-regulated by the overexpression of TgPDCD5. These results suggest that endogenous TgPDCD5 plays a role in macrophage apoptosis during T. gondii infection.

PMID: 19801898 [PubMed - in process]