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Biology subjects

Wu, C.-L.

Publications and source records attributed to Wu, C.-L..

23 records · Page 2Linked to original sources

Interpretable Deep Learning for De Novo Design of Cell-Penetrating Abiotic Polymers

There are more amino acid permutations within a 40-residue sequence than atoms on Earth. This vast chemical search space hinders the use of human learning to design functional polymers. Here we couple supervised and unsupervised deep learning with high-throughput experimentation to drive the design of high-activity, novel sequences reaching 10 kDa that deliver antisense oligonucleotides to the nucleus of cells. The models, in which natural and unnatural residues are represented as topological fingerprints, decipher and visualize sequence-activity predictions. The new variants boost antisense activity by 50-fold, are effective in animals, are nontoxic, and can also deliver proteins into the cytosol. Machine learning can discover functional polymers that enhance cellular uptake of biotherapeutics, with significant implications toward developing therapies for currently untreatable diseases. One sentence summaryDeep learning generates de novo large functional abiotic polymers that deliver antisense oligonucleotides to the nucleus.

bioinformatics↗

Prospective Isolation of Chondroprogenitors from Human iPSCs Based on Cell Surface Markers Identified using a CRISPR-Cas9-Generated Reporter

Articular cartilage shows little or no capacity for intrinsic repair, generating a critical need for regenerative therapies for joint injuries and diseases such as osteoarthritis. Human induced pluripotent stem cells (hiPSCs) offer a promising cell source for cartilage tissue engineering and in vitro human disease modeling; however, heterogeneity and off-target differentiation remain a challenge. We used a CRISPR-Cas9-edited COL2A1-GFP knock-in reporter hiPSC line, coupled with a surface marker screen, to identify a novel chondroprogenitor population expressing CD146, CD166, and PDGFR{beta}, but not CD45. Under chondrogenic culture conditions, these triple positive chondroprogenitor cells demonstrated decreased heterogeneity as measured by single cell RNA sequencing, as well as more robust and homogenous matrix production with significantly higher chondrogenic gene expression. Overall, this study has identified a unique hiPSC-derived subpopulation of chondroprogenitors that are CD146+/CD166+/PDGFR{beta}+/CD45- and exhibit high chondrogenic potential, providing a purified cell source for cartilage tissue engineering or disease modeling studies.

cell biology↗

Gene Therapy for Follistatin Mitigates Systemic Metabolic Inflammation and Post-Traumatic Osteoarthritis in High-Fat Diet-Induced Obese Mice

Obesity-associated inflammation and loss of muscle function play critical roles in the development of osteoarthritis (OA); thus, therapies that target muscle tissue may provide novel approaches to restoring metabolic and biomechanical dysfunction associated with obesity. Recent studies indicate that follistatin (FST), a protein which binds myostatin and activin, may have the potential to enhance muscle formation while neutralizing inflammation induced by these proteins. Here, we hypothesized that adeno-associated virus (AAV9) delivery of FST will enhance muscle formation and mitigate metabolic inflammation and knee OA caused by a high fat diet in mice. Obese mice receiving AAV-mediated FST delivery exhibited decreased inflammatory adipokines and cytokines systemically in the serum as well as locally in the joint synovial fluid. Regardless of diet, mice receiving FST gene therapy were protected from post-traumatic OA and bone remodeling induced by joint injury. While obesity disrupted the mitochondrial oxidative phosphorylation (OXPHOS) system in adipocytes, gene therapy for FST restored the key proteins involved in mitochondrial biogenesis, such as PPAR{gamma} coactivator 1 and AKT protein kinase 1, leading to the browning of white adipose tissue. Taken together, these findings suggest that FST gene therapy may provide a multifactorial therapeutic approach for injury-induced OA and metabolic inflammation in obesity.

physiology↗

A Genome-engineered Bioartificial Implant for Autoregulated Anti-Cytokine Drug Delivery

Biologic drug therapies are effective treatments for autoimmune diseases such as rheumatoid arthritis (RA) but may cause significant adverse effects, as they are administered continuously at high doses that can suppress the immune system. Using CRISPR-Cas9 genome editing, we engineered stem cells containing a synthetic gene circuit expressing biologic drugs to antagonize interleukin-1 (IL-1) or tumor necrosis factor (TNF) in an autoregulated, feedback-controlled manner in response to activation of the endogenous chemokine (C-C) motif ligand 2 (Ccl2) promoter. To test this approach in vivo, cells were tissue-engineered into a stable cartilaginous construct and implanted subcutaneously in mice with inflammatory arthritis. Bioengineered anti-cytokine implants mitigated arthritis severity as measured by joint pain, structural damage, and systemic and local inflammation. The coupling of synthetic biology with tissue engineering promises a range of potential applications for treating chronic diseases using custom-designed cells that express therapeutic transgenes in response to dynamically changing biological signals.Competing Interest StatementThe authors have declared no competing interest.View Full Text

synthetic biology↗

Highly efficient chondrogenic differentiation of human iPSCs and purification via a reporter allele generated by CRISPR-Cas9 genome editing

The differentiation of human induced pluripotent stem cells (hiPSCs) to prescribed cell fates enables the engineering of patient-specific tissue types, such as hyaline cartilage, for applications in regenerative medicine, disease modeling, and drug screening. In many cases, however, these differentiation approaches are poorly controlled and generate heterogeneous cell populations. Here we demonstrate robust cartilaginous matrix production in three unique hiPSC lines using a highly efficient and reproducible differentiation protocol. To purify chondroprogenitors produced by this protocol, we engineered a COL2A1-GFP knock-in reporter hiPSC line by CRISPR-Cas9 genome editing. Purified chondroprogenitors demonstrated an improved chondrogenic capacity compared to unselected populations. The ability to enrich for chrondroprogenitors and generate homogenous matrix without contaminating cell types will be essential for regenerative and disease modeling applications.

cell biology↗