Modulation of Microglial Cells Survival by IL4: Targeting the Neuroinflammation

SORIA, JA; ARROYO, DS; GAVIGLIO, EA; IRIBARREN, P

Congreso; First French-Argentine Immunology Congress; 2010

Sociedad Argentina de Inmunología

Microglial cells (MC) are the brain-resident immune cells. After acute activation, as a result of neuronal injury, MC proliferates, change their morphology (reactive microgliosis) and secrete neurotoxic factors. The activities of these cells are mostly beneficial, becoming destructive only when they escape from the strict control normally made by the Central Nervous System (CNS) envirnment. Downregulation of inflammatory mediators and removal of activated microglia may be key underlying mechanisms by which brain inflammation is controlled. Furthermore, anti-inflammatory cytokines, such as IL-4 and IL-13, may participate in these regulatory mechanisms present in the CNS. Therefore, we evaluated the effects of IL-4 on MC survival. Here, we show that IL4 induced a significant increase in the apoptosis of N9 microglial cells after 48 h of culture (hypodiploid DNA content, p = 0.0001). IL4 also increased the percentage of annexin-V single positive and annexin-V/7AAD double positive cells, indicating induction of early and late apoptosis respectively. In addition, we found that IL4 significantly increased the cleavage of caspase 3 (p