Molecular Therapy最新文献

In clinical trials, mesenchymal stromal/stem cells (MSCs) have consistently demonstrated safety. However, demonstration of efficacy has been inconsistent and many MSC trials have failed to meet their efficacy endpoint. This disappointing reality is reflected by the limited number MSC therapies approved by regulatory agencies, despite the large number of MSC trials registered on clinicaltrials.gov. Notably, there has been a recent approval of an MSC therapy for pediatric graft-vs.-host disease in the United States, marking the first MSC therapy approved by the U.S. Food and Drug Administration. This review provides a background of the history and potential therapeutic value of MSCs, an overview of MSC products with regulatory approval, and a summary of registered MSC trials. It concludes with a discussion on current and ongoing challenges and questions surrounding MSC therapy that remains to be resolved before becoming available for routine clinical use outside of clinical trials.

Zika virus (ZIKV) is an arbovirus associated with neurological disorders accompanying congenital infections. With no vaccine or antiviral approved, there is an urgent need for the development of effective antiviral agents against ZIKV infection. We evaluated the anti-ZIKV and immunomodulatory activity of ouabain, a Na⁺/K⁺-ATPase inhibitor known to have immunomodulatory and antiviral activities, using human neural stem and progenitor cells (hNS/PCs) and a murine model of congenital Zika syndrome (CZS). Our data demonstrated that ouabain reduces ZIKV infection in hNS/PCs, mouse placenta, yolk sac, and the fetal head. Ouabain mitigated neurogenesis impairment triggered by ZIKV in hNS/PCs and prevented ZIKV-mediated reduction of fetus and head sizes. In addition, ouabain decreased tumor necrosis factor and interleukin-1β levels in the placenta, highlighting its immunomodulatory activity in the murine model. Our findings indicate that ouabain possesses anti-ZIKV and immunomodulatory activities, suggesting that it should be investigated further as a promising treatment for CZS.

Effectively targeting intracellular pathways in cancers requires a system that specifically delivers to tumors and internalizes into cancer cells. To achieve this goal, we developed intracellular-delivering (ID) Salmonella with controllable expression of flhDC to regulate flagella production and cell invasion. We hypothesized that controlling flhDC would overcome the poor colonization seen in prior clinical trials. To test this hypothesis, we incorporated the aspirin-responsive Psal promoter and tuned flhDC expression with ssra degradation tags. In tumor-bearing mice, controlling flhDC increased protein release, tissue dispersion, and tumor colonization more than 10 million times. We discovered that inducing flhDC increases escape from intracellular vacuoles; however, deleting sseJ prevented escape and further increased protein delivery. Delivering constitutively active caspase-3 with ID-f-s Salmonella (ΔsseJ and induced Psal-flhDC) induced cell death in pancreatic, breast, and liver cancer cells and reduced the growth of breast tumors. This clinically ready strain preferentially colonized metastatic breast tissue 280 and 800 times more than surrounding healthy tissue in the lung and liver, respectively. By precisely controlling tumor colonization and cell invasion, this strain overcomes critical limitations of bacterial therapy and will enable treatment of many hard-to-treat cancers.

Oncolytic viruses have been considered promising cancer immunotherapies. However, oncovirotherapy agents impart durable responses in only a subset of cancer patients. Thus, exploring the cellular and molecular mechanisms underlying the heterogeneous responses in patients can provide guidance to develop more effective oncolytic virus therapies. Single-cell RNA sequencing (scRNA-seq) analysis of tumors responsive and non-responsive to oncovirotherapy revealed signatures of the tumor immune microenvironment associated with immune response. Thus, we designed and constructed an armed oncolytic virus, OV-5A, that expressed five genes with non-redundant functions. OV-5A treatment exhibits robust immune response against various tumors in multiple mouse models, peripheral blood mononuclear cell -patient-derived xenograft models, organoid-immune cell co-culture systems, and patient tissue sections by activating a cooperative innate-adaptive immune response against tumor cells. scRNA-seq analysis of complete responders and partial responders to OV-5A treatment guided the design of combination therapy of OV-5A. This data-driven approach paves an innovative way to rationalize the design of oncolytic virus and multi-agent combination therapies.

Neurons in the CNS lose regenerative potential with maturity, leading to minimal corticospinal tract (CST) axon regrowth after spinal cord injury (SCI). In young rodents, knockdown of PTEN, which antagonizes PI3K signaling by hydrolyzing PIP3, promotes axon regeneration following SCI. However, this effect diminishes in adults, potentially due to lower PI3K activation leading to reduced PIP3. This study explores whether increased PIP3 generation can promote long-distance regeneration in adults. We used a hyperactive PI3K, PI3Kδ (PIK3CD), to boost PIP3 levels in mature cortical neurons and assessed CST regeneration after SCI. Adult rats received AAV1-PIK3CD and AAV1-eGFP, or AAV1-eGFP alone, in the sensorimotor cortex concurrent with a C4 dorsal SCI. Transduced neurons showed increased pS6 levels, indicating elevated PI3K/Akt/mTOR signaling. CST regeneration, confirmed with retrograde tracing, was evaluated up to 16 weeks post injury. At 12 weeks, ∼100 axons were present at lesion sites, doubling to 200 by 16 weeks, with regeneration indices of 0.1 and 0.2, respectively. Behavioral tests showed significant improvements in paw reaching, grip strength, and ladder-rung walking in PIK3CD-treated rats, corroborated by electrophysiological recordings of cord dorsum potentials and distal flexor muscle electromyography. Thus, PI3Kδ upregulation in adult cortical neurons enhances axonal regeneration and functional recovery post SCI.

The orchestration of dynamic epigenetic and epitranscriptomic modifications is pivotal for the fine-tuning of gene expression. However, these modifications are traditionally examined independently. Recent compelling studies have disclosed an interesting communication and interplay between m6A RNA methylation (m6A epitranscriptome) and epigenetic modifications, enabling the formation of feedback circuits and cooperative networks. Intriguingly, the interaction between m6A and DNA methylation machinery, coupled with the crosstalk between m6A RNA and histone modifications shape the transcriptional profile and translational efficiency. Moreover, m6A modifications interact also with non-coding RNAs, modulating their stability, abundance, and regulatory functions. In the light of these findings, m6A imprinting acts as a versatile checkpoint, linking epigenetic and epitranscriptomic layers toward a multilayer and time-dependent control of gene expression and cellular homeostasis. The scope of the present review is to decipher the m6A-coordinated circuits with DNA imprinting, chromatin architecture, and non-coding RNAs networks in normal physiology and carcinogenesis. Ultimately, we summarize the development of innovative CRISPR-dCas engineering platforms fused with m6A catalytic components (m6A writers or erasers) to achieve transcript-specific editing of m6A epitranscriptomes that can create new insights in modern RNA therapeutics.

B cells are an attractive platform for engineering to produce protein-based biologics absent in genetic disorders, and potentially for the treatment of metabolic diseases and cancer. As part of pre-clinical development of B cell medicines, we demonstrate a method to collect, ex vivo expand, differentiate, radioactively label, and track adoptively transferred non-human primate (NHP) B cells. These cells underwent 10- to 15-fold expansion, initiated IgG class switching, and differentiated into antibody-secreting cells. Zirconium-89-oxine-labeled cells were infused into autologous donors without any preconditioning and tracked by PET/CT imaging. Within 24 h of infusion, 20% of the initial dose homed to the bone marrow and spleen and distributed stably and equally between the two. Interestingly, approximately half of the dose homed to the liver. Image analysis of the bone marrow demonstrated inhomogeneous distribution of the cells. The subjects experienced no clinically significant side effects or laboratory abnormalities. A second infusion of B cells into one of the subjects resulted in an almost identical distribution of cells, suggesting possibly a non-limiting engraftment niche and feasibility of repeated infusions. This work supports the NHP as a valuable model to assess the potential of B cell medicines as potential treatment for human diseases.