Validation of [125I]CPCR4.3 as an investigative tool for the sensitive and specific detection of hCXCR4 and mCXCR4 expression in vitro and in vivo.

Due to its excellent hCXCR4 and mCXCR4 targeting efficiency, both in vitro and in vivo, [125I]CPCR4.3 represents a sensitive and reliable tool for the species-independent quantification of CXCR4 expression. Its suboptimal clearance properties will certainly restrict its use for in vivo imaging applications using 123I (for SPECT) or 124I (for PET), but due to its high and specific accumulation in mCXCR4 expressing tissues, [125I]CPCR4.3 holds promise as a powerful preclinical tool for the investigation and quantification of CXCR4 involvement and kinetics in various murine disease models via, e.g., biodistribution and autoradiography studies.