5l79

Publication Abstract from PubMed

In designing new tracers consisting of a small-peptide conjugated to a reporter of comparable size, particular attention needs to be paid to the selection of the reporter group which can dictate both the in vitro and in vivo performances of the whole conjugate. In the case of fluorescent tracers, this is particularly true given the large numbers of available dye moieties differing in their structures and properties. Here, we have investigated the in vitro and in vivo properties of a novel series of MMP-12 selective probes composed of cyanine dyes varying in their structure, net charge and hydrophilic character, tethered through a linker to a potent and specific MMP-12 phosphinic pseudo peptide inhibitor. The impact of linker length has been also explored. The crystallographic structure of one tracer in complex with MMP-12 has been obtained, providing the first crystal structure of a Cy5.5-derived probe and confirming that the binding of the targeting moiety is unaffected. MMP-12 remains the tracers privileged target as attested by their affinity selectivity profile evaluated in solution towards a panel of twelve metalloproteases. In vivo assessment of four selected probes has highlighted the impact of the dye structure, but also that of the linker length on the probes blood clearance rates and their biodistributions. These experiments have also provided valuable data on the stability of the dyes moieties in vivo. This has permitted the identification of one probe, which combines favorable binding to MMP-12 in solution and on cells with optimized in vivo performance including blood clearance rate suitable for short-time imaging. Through this series of tracers, we have identified various critical factors modulating the tracers' in vivo behavior, both useful for the development and optimization of MMP-12 selective radiolabeled tracers and informative for the design of fluorescent probes in general.

Synthesis, in vitro and in vivo evaluation of MMP-12 selective optical probes.,Bordenave T, Helle M, Beau F, Georgiadis D, Tepshi L, Bernes M, Yunpeng Y, Levenez L, Poquet E, Nozach H, Razavian M, Toczek J, Stura EA, Dive V, Sadeghi MM, Devel L Bioconjug Chem. 2016 Aug 26. PMID:27564088^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.