Molecular imaging of human embryonic stem cells

Area of Science:

• Regenerative Medicine
• Molecular Imaging
• Stem Cell Biology

Background:

• Human embryonic stem cells (hESCs) offer potential for tissue regeneration but face challenges like teratoma formation and immune rejection.
• Clinical translation requires methods to monitor hESC behavior in vivo, including localization, proliferation, and viability.

Purpose of the Study:

• To develop and apply novel molecular imaging techniques for longitudinal monitoring of hESCs in living subjects.
• To address safety concerns and assess the feasibility of hESC transplantation therapy.

Main Methods:

• Creation of a fusion reporter construct encoding red fluorescent protein (RFP), firefly luciferase (fluc), and herpes simplex virus thymidine kinase (HSV-tk).
• Utilizing multimodal imaging techniques: optical fluorescence, bioluminescence, and positron emission tomography (PET).

Main Results:

• The reporter construct enables noninvasive, longitudinal tracking of hESC engraftment and proliferation.
• The system allows for investigation of spatio-temporal kinetics of hESCs in vivo.
• Potential for isolating homogenous hESC populations and enabling graft ablation if necessary.

Conclusions:

• Reporter gene imaging accelerates basic science and clinical research involving hESCs.
• This multimodal imaging approach supports safe and effective hESC transplantation therapy.
• The developed system facilitates monitoring, isolation, and control of hESC behavior in vivo.