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Cell Surface Marker Mediated Purification of iPS Cell Intermediates from a Reprogrammable Mouse Model
Published on: September 6, 2014
Functionality and transduction condition evaluation of recombinant Klf4 for improved reprogramming of iPS cells
Yong Tang1, Chih-Jen Lin, X Cindy Tian
1Center for Regenerative Biology, Department of Animal Science, University of Connecticut, 1390 Storrs Road, Storrs, CT 06269, USA.
Cellular Reprogramming
|April 9, 2011
Summary
Protein-based reprogramming using Klf4 fused with cell-penetrating peptides (CPPs) offers a safer alternative to viral methods for generating induced pluripotent stem cells (iPSCs). This study demonstrates effective iPSC generation with Klf4-CPP proteins, advancing regenerative therapy potential.
Area of Science:
- Stem Cell Biology
- Regenerative Medicine
- Molecular Biology
Background:
- Induced pluripotent stem cell (iPSC) technology is crucial for regenerative therapy.
- Protein-based reprogramming (piPSC) avoids genomic alteration risks but faces efficiency challenges.
- Klf4 protein delivery methods require optimization for enhanced reprogramming.
Purpose of the Study:
- To evaluate the reprogramming potential of purified mouse Klf4 proteins linked with cell-penetrating peptides (CPPs).
- To compare CPPs like HIV TAT and Drosophila Penetratin at different protein termini.
- To optimize protein transduction conditions for efficient piPSC generation.
Main Methods:
- Purified recombinant Klf4 proteins fused with TAT or Penetratin CPPs were generated.
- Klf4-CPP proteins were used in combination with retroviral Oct4, Sox2, and c-Myc (OSM) for reprogramming mouse fibroblasts.
- Protein localization and iPSC induction efficiency were assessed under various transduction conditions.
Main Results:
- Both TAT- and Penetratin-linked Klf4 proteins significantly induced mouse iPSC formation at nanomolar concentrations within 2-4 weeks.
- A fusion protein with Discosoma red fluorescent protein (DsRed) between TAT and Klf4 showed significant iPSC induction.
- Four serial transductions with purified Klf4 proteins proved sufficient for effective iPSC induction.
Conclusions:
- TAT- and Penetratin-linked Klf4 proteins effectively replace viral Klf4 in reprogramming fibroblasts.
- This protein-based approach offers a safer and potentially more efficient method for generating piPSCs.
- The study provides a valuable strategy for evaluating recombinant proteins and optimizing transduction for piPSC induction.
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