MIP1

MIP-1, short for macrophage inflammatory protein-1, refers to two related chemokines, MIP-1α and MIP-1β, encoded in humans by the CCL3 and CCL4 genes. They are members of the CC chemokine family and are produced by macrophages, dendritic cells, T cells, and other cell types in response to inflammatory or infectious stimuli.

The primary role of MIP-1α (CCL3) and MIP-1β (CCL4) is to act as chemoattractants that recruit immune cells to sites of infection or tissue damage. They help direct the movement of monocytes, T lymphocytes, natural killer cells, and other leukocytes, contributing to the orchestration of both innate and adaptive immune responses. Their activity is mediated through binding to chemokine receptors, particularly CCR1 and CCR5, with CCR5 playing a central role in guiding cells that express this receptor.

MIP-1 levels can be elevated in a variety of inflammatory conditions and have been studied in the context of autoimmune diseases and infections. A notable aspect of their biology is their interaction with CCR5, a co-receptor used by certain strains of HIV-1 to enter cells; as natural ligands for CCR5, MIP-1 chemokines can influence susceptibility to infection and disease progression, and they have been considered in discussions of HIV-related therapeutics and CCR5-targeted interventions.

Genes CCL3 and CCL4 encode MIP-1α and MIP-1β, respectively. The two chemokines are closely related in sequence and function, often co-expressed, yet they can differ in receptor binding profiles and biological potency.