Cellular context and ligand class shape CXCR4-CCR5 heteromerization in live cells. (PubMed, Res Sq)
Agonists induced transient heteromerization coupled to receptor internalization, while antagonists, especially plerixafor together with maraviroc, stabilized persistent surface-associated complexes. Molecular dynamics simulations in asymmetric bilayers resembling MDA-MB-231 and MCF-10A membranes identified cholesterol-enriched receptor interfaces that prolong CXCR4-CCR5 dimer lifetimes in MDA-like membranes. These results show that GPCR heteromerization is not an intrinsic fixed property of receptor pairs, but an emergent behavior shaped by cell state, lipid environment, and ligand input.