Signal transduction is a complex process involving receptor activation, protein complex assembly, post-translational modifications, second messenger systems, and nuclear events. It includes intricate mechanisms such as protein-protein interactions, integration of signals, and gene expression regulation. These processes ensure the precise transmission of signals from the cell surface to the nucleus, resulting in a cellular response.

Chemokines are a subset of cytokines crucial for immune responses. They create gradients that guide immune cells to sites of infection or inflammation. Additionally, they modulate immune cell activity by influencing processes like activation, differentiation, proliferation, cytokine production, and adhesion for an effective and targeted response.

Cytokines, vital for cell communication and immune function, are categorized into families with pro-inflammatory and anti-inflammatory members. Examples include Interleukins, Tumor Necrosis Factor, Interferons, Chemokines, and Transforming Growth Factor-beta. Immune receptors, like the Cytokine Receptor Superfamily and TNF Receptor Superfamily, are crucial for recognizing specific cytokines and initiating cellular responses.