Pro inflammatory cytokines are signaling molecules that are secreted by immune cells in response to infection or injury. They play a crucial role in initiating and sustaining the inflammatory response. These cytokines include Interleukin-1 (IL-1), Interleukin-6 (IL-6), Tumor Necrosis Factor-alpha (TNF-α), and others. They act by binding to specific receptors on target cells, triggering a cascade of events that lead to inflammation.