ROCK inhibition enhanced hepatocyte liver engraftment by retaining membrane CD59 and attenuating complement activation.

Hepatocyte transplantation can be an effective treatment for patients with certain liver-based metabolic disorders and liver injuries. Hepatocytes are usually infused into the portal vein, from which hepatocytes migrate into the liver and integrate into the liver parenchyma. However, early cell loss and poor liver engraftment represent major hurdles to sustaining the recovery of diseased livers after transplantation. In the present study, we found that ROCK (Rho-associated kinase) inhibitors significantly enhanced in vivo hepatocyte engraftment. Mechanistic studies suggested that the isolation of hepatocytes caused substantial degradation of cell membrane proteins, including the complement inhibitor CD59, probably due to shear stress-induced endocytosis. ROCK inhibition by ripasudil, a clinically used ROCK inhibitor, can protect transplanted hepatocytes by retaining cell membrane CD59 and blocking the formation of the membrane attack complex. Knockdown of CD59 in hepatocytes eliminates ROCK inhibition-enhanced hepatocyte engraftment. Ripasudil can accelerate liver repopulation of fumarylacetoacetate hydrolase-deficient mice. Our work reveals a mechanism underlying hepatocyte loss after transplantation and provides immediate strategies to enhance hepatocyte engraftment by inhibiting ROCK.

Chemical approach to generating long-term self-renewing pMN progenitors from human embryonic stem cells.

Spinal cord impairment involving motor neuron degeneration and demyelination can cause lifelong disabilities, but effective clinical interventions for restoring neurological functions have yet to be developed. In early spinal cord development, neural progenitors of the motor neuron (pMN) domain, defined by the expression of oligodendrocyte transcription factor 2 (OLIG2), in the ventral spinal cord first generate motor neurons and then switch the fate to produce myelin-forming oligodendrocytes. Given their differentiation potential, pMN progenitors could be a valuable cell source for cell therapy in relevant neurological conditions such as spinal cord injury. However, fast generation and expansion of pMN progenitors in vitro while conserving their differentiation potential has so far been technically challenging. In this study, based on chemical screening, we have developed a new recipe for efficient induction of pMN progenitors from human embryonic stem cells. More importantly, these OLIG2+ pMN progenitors can be stably maintained for multiple passages without losing their ability to produce spinal motor neurons and oligodendrocytes rapidly. Our results suggest that these self-renewing pMN progenitors could potentially be useful as a renewable source of cell transplants for spinal cord injury and demyelinating disorders.

Retzius-sparing robot-assisted radical prostatectomy improves early recovery of urinary continence: a randomized, controlled, single-blind trial with a 1-year follow-up.

OBJECTIVE: To evaluate the impact of Retzius-sparing robot-assisted radical prostatectomy (posterior approach) on early recovery of urinary continence (UC) compared to the conventional approach (anterior approach) for the treatment of clinically localized prostate cancer (PCa). METHODS: A total of 110 consecutive patients with clinically localized PCa were prospectively randomized in a 1:1 ratio to an anterior group (n = 55) or a posterior group (n = 55). The primary outcome was immediate UC, defined as freedom from any pad use within 1 week after removal of the urinary catheter. The UC rate following surgery was also calculated with Kaplan-Meier curves, and the log-rank test was used for statistical comparison. Intra-operative outcomes, pathological data and oncological outcomes, including positive surgical margin (PSM) status and biochemical recurrence-free survival (BCRFS), were also compared between the two groups. The comparison of the two approaches was also analysed in subgroups after risk stratification. RESULTS: Of the patients who underwent the posterior approach, 69.1% achieved immediate UC compared with 30.9% in the anterior group (relative risk 2.24, 95% confidence interval [CI] 1.48-3.51; P = 0.000). The relative Kaplan-Meier curves for UC during the 12-month follow-up revealed statistically better recovery in the posterior group when compared with the anterior group (hazard ratio [HR] 1.51, 95% CI 1.01-2.24; log-rank P = 0.007). No statistically significant differences were observed between the groups regarding complications (P = 0.399), PSM status (P = 0.225) or BCRFS (HR 4.80, 95% CI 0.97-23.78; log-rank P = 0.111). In sub-analyses, no significant difference between the two approaches with regard to UC recovery in patients with high-risk PCa was observed (HR 1.26, 95% CI 0.63-2.51; log-rank P = 0.415). CONCLUSIONS: The Retzius-sparing approach significantly improved early recovery of UC compared to the conventional approach. Further prospective studies are needed to confirm the benefits of the Retzius-sparing approach for clinically localized PCa, especially for high-risk cases.

Maintenance of Primary Hepatocyte Functions In Vitro by Inhibiting Mechanical Tension-Induced YAP Activation.

Hepatocytes are the primary functional cells of the liver, performing its metabolic, detoxification, and endocrine functions. Functional hepatocytes are extremely valuable in drug discovery and evaluation, as well as in cell therapy for liver diseases. However, it has been a long-standing challenge to maintain the functions of hepatocytes in vitro. Even freshly isolated hepatocytes lose essential functions after short-term culture for reasons that are still not well understood. In the present study, we find that mechanical tension-induced yes-associated protein activation triggers hepatocyte dedifferentiation. Alleviation of mechanical tension by confining cell spreading is sufficient to inhibit hepatocyte dedifferentiation. Based on this finding, we identify a small molecular cocktail through reiterative chemical screening that can maintain hepatocyte functions over the long term and in vivo repopulation capacity by targeting actin polymerization and actomyosin contraction. Our work reveals the mechanisms underlying hepatocyte dedifferentiation and establishes feasible approaches to maintain hepatocyte functions.

Fast and Accurate 3D Measurement Based on Light-Field Camera and Deep Learning.

The precise combination of image sensor and micro-lens array enables light-field cameras to record both angular and spatial information of incoming light, therefore, one can calculate disparity and depth from one single light-field image captured by one single light-field camera. In turn, 3D models of the recorded objects can be recovered, which means a 3D measurement system can be built using a light-field camera. However, reflective and texture-less areas in light-field images have complicated conditions, making it hard to correctly calculate disparity with existing algorithms. To tackle this problem, we introduce a novel end-to-end network VommaNet to retrieve multi-scale features from reflective and texture-less regions for accurate disparity estimation. Meanwhile, our network has achieved similar or better performance in other regions for both synthetic light-field images and real-world data compared to the state-of-the-art algorithms.