Limited protection of TAT-Bcl-XL against pneumolysin-induced neuronal cell death

Objectives: The severe brain damage that patients with pneumococcal meninigits often suffer is in part caused by the cytosolic pneumococcal protein pneumolysin. The devastating effect of this neurotoxin might be alleviated by interfering with the death pathways that it sets in motion. An important player in these death pathways is Bcl-XL, an antiapoptotic protein of the Bcl-2 family, which is neuroprotective in various in vitro and in vivo systems. We investigated whether its membrane-permeable form, the TAT-Bcl-XL fusion protein, is capable of protecting human SH-SY5Y neuroblastoma cells against pneumolysin-ind…