The innate immune response (IIR) is the first-line of the body's immune response to invaders, they are non-specific; they are not tailored to a specific invader or antigen. This is as opposed to the adaptive immune response (AIR) which is antigen-specific and keeps records of how it fought off past invaders. Examples of cells of the IIR include:
- Granulocytes, including basophils, eosinophils and neutrophils
- Dendritic cells (although their primary role is in antigen presentation, in order to activate the adaptive immune response)
- NK cells
Additional components of the IIR include the complement system (although the AIR can also activate this system), toll-like receptors and other microbe-recognition receptors and epithelial barriers (e.g., the skin) that prevent microbes from gaining entry into the body in the first place.