Figure 2.

The multifaceted roles of Treg and Teff in neurodegenerative disorders. For neurodegenerative disease (HAND, PD, AD, ALS), Teff and Treg exert opposing influences on neuronal function and speeding neurodestruction or neuroprotection, respectively. However, in early stage disease immunoregulatory control responses are operative and initiated by Treg to modulate MP homeostatic function and promote neuronal integrity. However, as disease progresses Teff up-regulate neurotoxic molecules and exacerbate MP activation and dysfuction, while Treg attenuate these neurotoxic responses. Treg modulate neuronal survival and function and could occur through changes the phenotype of the M1, pro-inflammatory brain MP to an M2 phenotype. The latter is an alternatively activated macrophage that possesses anti-inflammatory and potential neuroprotective functions.