Stem cells have the potential to revolutionize medical practice by enabling regenerative medicine. This proposal aims to develop highly efficient generation of human induced pluripotent stem cells (hiPSCs) by utilizing a new class of nanoparticle (NP)-based vectors. These NPs are capable of delivering reprogramming transcription factors (TFs), namely OCT4, SOX2, KLF4 and c-MYC. Current reprogramming systems raise safety concerns because they utilize viral expression of the four key TFs, resulting in hiPSCs with multiple viral integrations. Safer strategies for generating hiPSCs have recently been demonstrated by introducing cell- penetrating peptide-fused reprogramming TFs into human somatic cells, averting any potential dangers of genetic manipulation. Still, effective delivery of TFs remains a key obstacle in creating hiPSCs. Three research groups at UCLA with expertise covering synthetic chemistry, nanoparticles, microfluidics (Tseng and Lu) and stem cell biology (Pyle) have collaborated and accomplished preliminary results consisting of the following fundamental proof-of-concept studies: (i) self-assembly production of supramolecular nanoparticles (SNPs) for delivery of TFs, (ii) (ii) a single protein nano-capsule technology, (iii) digital microreactors for large-scale screening, (iv) microfluidic image cytometry (MIC) technology for quantitative phenotyping of single hiPSCs, and (v) extensive experience in generating hiPSCs. The proposed research will leverage the multidisciplinary team to implement the following two specific aims: 1) We will synthesize a variety of polymer building blocks, cross linkers, functional ligands, as well as, nano- capsules containing the four reprogramming TFs for self-assembly of SNP-based delivery vectors. 2) We will generate a combinatorial library of reprogramming TF-encapsulated SNPs (i.e., OCT4/SOX2/ KLF4/c-MYC?SNPs) by performing ratiometric mixing of the four TF-containing nano-capsules, polymer building blocks, cross linkers and functional ligands. Human ESC-derived fibroblast cells with an OCT4-EGFP reporter will be employed as target cells. Subsequently, the MIC technology will be employed to quantify reprogramming performance by measuring pluripotent markers and colony formation in the SNPs-treated cells. If the efficiency is too low, we propose to co-deliver apoptotic inhibitors (e.g., siRNA_p53) with the four reprogramming TFs using siRNA/TFs?SNPs-based vectors. We anticipate that combination of apoptotic inhibitors and reprogramming TFs could dramatically increase the efficiency of reprogramming.

Public Health Relevance

The long-term objective of this research proposal is to explore the use of supramolecular nanoparticles (SNPs) as a new category of artificial vector for simultaneous delivery of the four reprogramming transcription factors (i.e., OCT4, SOX2, KLF4 and c-MYC) into human somatic cells to induce reprogramming to the induced pluripotent cell (iPSC) state.

National Institute of Health (NIH)
National Institute of General Medical Sciences (NIGMS)
Exploratory/Developmental Grants (R21)
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Nanotechnology Study Section (NANO)
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Haynes, Susan R
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University of California Los Angeles
Schools of Medicine
Los Angeles
United States
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Choi, Jin-Sil; Zhu, Yazhen; Li, Hongsheng et al. (2017) Cross-Linked Fluorescent Supramolecular Nanoparticles as Finite Tattoo Pigments with Controllable Intradermal Retention Times. ACS Nano 11:153-162
Liu, Yang; Du, Juanjuan; Choi, Jin-sil et al. (2016) A High-Throughput Platform for Formulating and Screening Multifunctional Nanoparticles Capable of Simultaneous Delivery of Genes and Transcription Factors. Angew Chem Int Ed Engl 55:169-73
Hou, Shuang; Choi, Jin-Sil; Garcia, Mitch Andre et al. (2016) Pretargeted Positron Emission Tomography Imaging That Employs Supramolecular Nanoparticles with in Vivo Bioorthogonal Chemistry. ACS Nano 10:1417-24
Hou, Shuang; Choi, Jin-sil; Chen, Kuan-Ju et al. (2015) Supramolecular nanosubstrate-mediated delivery for reprogramming and transdifferentiation of mammalian cells. Small 11:2499-504
Peng, Jinliang; Garcia, Mitch André; Choi, Jin-sil et al. (2014) Molecular recognition enables nanosubstrate-mediated delivery of gene-encapsulated nanoparticles with high efficiency. ACS Nano 8:4621-9
Lee, Jae-Hyun; Chen, Kuan-Ju; Noh, Seung-Hyun et al. (2013) On-demand drug release system for in vivo cancer treatment through self-assembled magnetic nanoparticles. Angew Chem Int Ed Engl 52:4384-4388
Liu, Yang; Wang, Hao; Kamei, Ken-ichiro et al. (2011) Delivery of intact transcription factor by using self-assembled supramolecular nanoparticles. Angew Chem Int Ed Engl 50:3058-62