The tracking of cells in vivo is a critical aspect of any cell-based therapy research program. Whether tracking stem cells, T-cells, or exotics like platelets, liposomes, and reporter gene constructs the question remains: how to tag the cell/particle for tracking and what behavior to track (blood circulation time, sequestration PK in organs/tumors,tissue residence time and concentration). The applications include determining the rate of T-cells targeting a tumor, to determining if implanted stem cells maintain tissue implant location or migrate, and determining the PK of platelets and MOA of drug induced thrombocytopenia.
At BioLaurus we have many years’ experience with a wide range of tagging methods for use in fluorescence, SPECT,PET, and ultrasound tracking. Our expertise includes reporter gene transduction (luciferase for BLI and TK for PET) invitro orin vivo HDTV.
The cell tracking image modalities are typically BLI for high sensitivity screening in mice, and SPECT and PET imaging for PK in rodents and larger animals including NHP.
One of the most challenging cell tracking studies are those with platelets (PLT). We specialize in this research and are leading experts in rabbit and NHP platelet studies. This work is crucial as a high percentage of drugs in the preclinical and clinical pipeline cause thrombocytopenia often through indirect processes . These drugs are from all classes of drugs including small molecules, antisence oligonucleotides, and biologics such as mini bodies. To study PLT circulation and tissue sequestration PK autologous PLT must be tagged (typically In-111) without activatingthe PLT. This is a formidable challenge requiring precision execution of our proprietary isolation and labeling protocol. The labeled PLT are reintroduced into the test subject and tracked by dynamic imaging for PK determination and/or over days (up to2 weeks) for survival curves. In our test system we have examined PLT PK in rabbits and NHP and examined autologous PLT, pooled PLT, and PLT replacement products.