Chemokinek

Chemokinek, also known as chemokines, are small secreted cytokines that direct the movement of circulating leukocytes and other cells by forming chemical gradients. They play essential roles in immune surveillance, development, inflammation, and tissue repair. Chemokinek are categorized into four main subfamilies based on the arrangement of their first two cysteine residues: CXC, CC, CX3C, and C. This grouping correlates with receptor usage and function; for example, many CXC chemokinek attract neutrophils, while CC chemokinek attract monocytes, T cells, and dendritic cells.

Chemokinek exert their effects by binding to chemokinek receptors, a family of G protein-coupled receptors expressed on target cells such as leukocytes and endothelial cells. Receptor engagement triggers intracellular signaling pathways that promote cytoskeletal rearrangement, adhesion, and directed migration toward higher chemokinek concentrations. Chemokinek can be constitutively expressed (homeostatic) to maintain cell trafficking, or induced by inflammatory stimuli (e.g., IL‑1, TNF) to recruit immune cells to sites of infection or injury. Some chemokinek also influence cell activation, survival, and angiogenesis.

Common chemokinek include CXCL8 (interleukin-8), CCL5 (RANTES), CCL2 (MCP-1), and CXCL12 (SDF-1), each with specific receptor partners such as CXCR1/2, CCR5, CCR2, and CXCR4. The chemokinek system is implicated in various diseases, including chronic inflammation, autoimmune disorders, and cancer metastasis. Because of their central role in cell trafficking, chemokinek receptors are explored as therapeutic targets. Examples include CCR5 antagonists (e.g., maraviroc) for HIV and CXCR4 antagonists (plerixafor) for stem cell mobilization; research continues into broader applications and selective inhibitors.