Stop! Or My Dog Will Shoot Wiggum, enroll him in the Springfield Animal Police Academy, where he is teamed with Lou, managing to help fight crime in Springfield. Santa's Little Helper catches Snake Jailbird who is taken to court, but freed on a technicality. This makes Santa's Little Helper jaded, and when he returns home, he bites Bart on the leg out of frustration. Considering the fact that the pressure from the fight against crime is what led to the dog's actions on Bart, the Simpsons send the dog away to live with Lou. As a replacement, Marge buys Bart a reticulated python, which he names
T helper cell because such knowledge may be very useful in the treatment of disease and in increasing the effectiveness of vaccination. Proliferating helper T cells that develop into effector T cells differentiate into two major subtypes of cells known as T1 and T2 cells (also known as Type 1 and Type 2 helper T cells, respectively). T1 helper cells lead to an increased cell-mediated response, typically against intracellular bacteria and protozoa. They are triggered by IL-12 and their effector cytokines are IFN-γ and IL-2. The main effector cells of T1 immunity are macrophages as well as CD8 T cells, IgG B cells,