Adaptive and innate immune reactions regulating mast cell activation: from receptor-mediated signaling to responses

Mast cells play a role in the body's defense mechanisms associated with innate and adaptive immune reactions. When activated by such reactions, mast cells secrete a diverse group of inflammatory mediators whose role is to help the body destroy or clear parasites, bacteria, and viruses. It is the same mediators produced by these defense mechanisms, however, that are responsible for the adverse inflammatory cellular reactions that are manifested in allergic disease states such as asthma. A better understanding of the mechanisms by which these immunologic processes affect mast cell activation may provide insight into how these detrimental aspects of mast cell activation may be isolated from the beneficial aspects. Thus, in this article, we discuss the current understanding about how innate and adaptive immune responses lead to the release of inflammatory mediators from mast cells and discuss the intracellular signaling mechanisms that regulate these responses.