as effector cells Microglia are located throughout the brain and spinal cord. They are the first line of immune defense in the CNS. Microglia are of utmost importance in brain maintenance. They constantly search around the CNS for any type of plaques, damaged neurons, and infections. Microglia are extremely sensitive forms of effector cells, because they must be alert enough to address possible life-threatening damage. This sensitivity is caused by unique forms of potassium channels. Microglia must always be capable of recognizing any foreign bodies, engulf them, and activate T-cells. Microglia can be found under a variety of different shapes and sizes, based on the location where they are found. The vast amount of shapes are required for the microglia to carry out their primary function. Microglia are distinguishable from macrophages because of their ability to transform, which allows them to protect the CNS under relatively short amounts of time. Microglia take on a unique phenotype when they detect local chemical signals. Microglia have a variety of different functions required to maintain homeostasis in the host body. Mast cells as effector cells A mast cell is a white blood cell. Mast cells are protective cells that are involved in wound healing and blood-brain barrier function. Mast cells are very similar to basophils, and mast cells once were mistaken for them. It is proven that the two cells have different lineages. Mast cells respond to pathogenic parasites through Immunoglobin E signaling. These cells play a role in the inflammatory process. They can either release selective amounts or rapid amounts of compounds that induce inflammation from granules. Mast cells are inactive during allergic reactions unless an allergen binds to Immunoglobin E. References Cellular processes Cell signaling