Cell death in the brain during parasitic infections.

Programmed cell death is an integral arm of immunity, especially in response to intracellular pathogen infection, for the release of inflammatory mediators, and the clearance of pathogen-infected cells. In the central nervous system, cell death as a form of immunity may seem paradoxical; neuronal health is critical to survival and neurogenesis is nominal post gestation. However, the brain is composed of various glial cell types that have a greater regenerative capacity than neurons, thus allowing for cell death to potentially be utilized as a protective immune response. While the brain is an immune privileged tissue, robust immune responses are mounted against many parasites that infect the brain. Recent work has demonstrated that cell death and subsequent inflammatory milieu induce strong neuroinflammatory responses. At the same time, multiple previously unappreciated programmed cell death pathways have begun to be detailed. This review will focus on various forms of cell death that occur during parasitic brain infection and the cell types that utilize them. While this is a burgeoning research focus, it is clear that under specific conditions cell death in the brain can be either detrimental or beneficial. In this review we will cover the implications of cell death on the outcome of numerous parasitic infections that impact the brain, meninges, and brain vasculature.