Cas9-mediated knockout of Ndrg2 enhances the regenerative potential of dendritic cells for wound healing.

Chronic wounds impose a significant healthcare burden to a broad patient population. Cell-based therapies, while having shown benefits for the treatment of chronic wounds, have not yet achieved widespread adoption into clinical practice. We developed a CRISPR/Cas9 approach to precisely edit murine dendritic cells to enhance their therapeutic potential for healing chronic wounds. Using single-cell RNA sequencing of tolerogenic dendritic cells, we identified N-myc downregulated gene 2 (Ndrg2), which marks a specific population of dendritic cell progenitors, as a promising target for CRISPR knockout. Ndrg2-knockout alters the transcriptomic profile of dendritic cells and preserves an immature cell state with a strong pro-angiogenic and regenerative capacity. We then incorporated our CRISPR-based cell engineering within a therapeutic hydrogel for in vivo cell delivery and developed an effective translational approach for dendritic cell-based immunotherapy that accelerated healing of full-thickness wounds in both non-diabetic and diabetic mouse models. These findings could open the door to future clinical trials using safe gene editing in dendritic cells for treating various types of chronic wounds.

Matrix Metalloproteinase-9 as a Potential Biomarker in 631 Human Implant-Induced Fibrotic Capsules: Analysis and Biomarker Study.

BACKGROUND: Capsular fibrosis (CF) often occurs around biomedical devices following implantation causing pain, discomfort, and device failure. Breast implantation remains among the most common medical procedures worldwide. Revealing specific genes that drive fibrotic deposition will help us to garner a better understanding of the pathophysiology of this disease and develop different strategies to combat it. METHODS: The authors collected 631 capsules around breast implants and were able to connect clinical baseline characteristics with histopathologic findings. In addition, the authors were able to conduct the first large systematic analysis to identify differentially expressed genes in fibrotic human tissue samples, comparing the lowest form of fibrosis with the most aggravated one. RESULTS: The authors identified 2559 differentially expressed genes on which they performed a knowledge-based network generation and pathway association study to identify putative novel biomarkers for CF. The authors were able to show changes of cellular influx during progression of CF and distinguish several genes as potential clinical biomarkers and drug targets. Among these, matrix metalloproteinase-9 was one of the most up-regulated ( P = 0.006) and is attractive because of its wide detectability. CONCLUSIONS: Matrix metalloproteinase-9 seems to be a potential biomarker to detect capsular fibrosis. It is a measurable indicator that can easily be detected in blood, sputum, and urine. For the diagnosis of fibrosis, this biomarker might be exceedingly beneficial to developing novel screening methods and prophylaxes. CLINICAL RELEVANCE STATEMENT: Discovering biomarkers at the earliest and mildest stages for the diagnosis of fibrosis is clinically important. These results bring new hope for biomarker-based diagnosis for capsular fibrosis. CLINICAL QUESTION/LEVEL OF EVIDENCE: Diagnostic, V.

Epidermal-Derived Hedgehog Signaling Drives Mesenchymal Proliferation during Digit Tip Regeneration.

Hand injuries often result in significant functional impairments and are rarely completely restored. The spontaneous regeneration of injured appendages, which occurs in salamanders and newts, for example, has been reported in human fingertips after distal amputation, but this type of regeneration is rare in mammals and is incompletely understood. Here, we study fingertip regeneration by amputating murine digit tips, either distally to initiate regeneration, or proximally, causing fibrosis. Using an unbiased microarray analysis, we found that digit tip regeneration is significantly associated with hair follicle differentiation, Wnt, and sonic hedgehog (SHH) signaling pathways. Viral over-expression and genetic knockouts showed the functional significance of these pathways during regeneration. Using transgenic reporter mice, we demonstrated that, while both canonical Wnt and HH signaling were limited to epidermal tissues, downstream hedgehog signaling (through Gli) occurred in mesenchymal tissues. These findings reveal a mechanism for epidermal/mesenchyme interactions, governed by canonical hedgehog signaling, during digit regeneration. Further research into these pathways could lead to improved therapeutic outcomes after hand injuries in humans.

Mortality Trends in Chronic Liver Disease and Cirrhosis in the United States, Before and During COVID-19 Pandemic.

Chronic liver disease (CLD) and cirrhosis accounts for approximately 2 million deaths annually worldwide. CLD and cirrhosis-related mortality has increased steadily in the United States.1,2 With the global pandemic of coronavirus disease 2019 (COVID-19), patients with CLD and cirrhosis represent a vulnerable population at higher risk for complications and mortality.3,4 Although high mortality from COVID-19 among patients with CLD and cirrhosis have been reported,5 national trends in mortality related to CLD and cirrhosis before and during the COVID-19 pandemic have not been assessed. This study estimated the temporal quarterly trends in CLD and cirrhosis-related mortality in the United States from 2017 Q1 to 2020 Q3 using provisional data releases from the National Vital Statistics System.6,7.

SEM and TEM for identification of capsular fibrosis and cellular behavior around breast implants - a descriptive analysis.

BACKGROUND: Capsular fibrosis (CF) is the most common long-term complication in implant-based breast augmentation. It is well accepted that the foreign body response (FBR) instigates the development of fibrotic disease. Our study aims to compare murine and human samples of CF and describe the cellular and extracellular matrix (ECM) composition using scanning and transmission electron microscopy (SEM and TEM). RESULTS: Miniature microtextured silicone breast implants were implanted in mice and subsequently harvested at days 15, 30, and 90 post-operation. Isolated human capsules with the most aggravated form of CF (Baker IV) were harvested post-operation. Both were analyzed with SEM and TEM to assess cellular infiltration and ECM structure. An architectural shift of collagen fiber arrangement from unidirectional to multidirectional was observed at day 90 when compared to days 15 and 30. Fibrosis was observed with an increase of histiocytic infiltration. Moreover, bacterial accumulation was seen around silicone fragments. These findings were common in both murine and human capsules. CONCLUSIONS: This murine model accurately recapitulates CF found in humans and can be utilized for future research on cellular invasion in capsular fibrosis. This descriptive study helps to gain a better understanding of cellular mechanisms involved in the FBR. Increases of ECM and cellularity were observed over time with SEM and TEM analysis.

Trends in the Mortality of Biliary Tract Cancers Based on Their Anatomical Site in the United States From 2009 to 2018.

INTRODUCTION: Recent trends in the incidence and mortality of biliary tract cancers are unknown. We estimated the trends in biliary tract cancers-related incidence and mortality stratified by anatomical site, age, sex, and race/ethnicity in the US adults. METHODS: We performed a population-based trend analysis using the US national incidence (2009-2017) and mortality records (2009-2018). We identified age-standardized incidence and mortality from intrahepatic cholangiocarcinoma (ICC), extrahepatic cholangiocarcinoma, gallbladder cancer, and ampulla of Vater cancer using appropriate ICD-10 code. Temporal mortality was calculated by joinpoint trend analysis with estimates of annual percentage change (APC) described as each trend segment. RESULTS: The incidence rates of ICC increased linearly (APC 8.9%, 95% confidence interval [CI] 7.8%-10.0%) while gallbladder cancer-related incidence rates remained stable early and decreased significantly later in the study (APC -2.8%, 95% CI -5.5% to -0.0% [2014-2017]). Age-standardized mortality from biliary tract cancers steadily increased with an annual increase of 2.0% (95% CI 1.6%-2.3%). Although there was a linear increase in the ICC-related mortality (APC 3.5%, 95% CI 3.1%-3.8%), extrahepatic cholangiocarcinoma-related mortality tended to remain stable earlier and increased later (APC 7.0%, 95% CI 4.6%-9.5% [2013-2018]). By contrast, gallbladder cancer-related mortality steadily decreased over 10 years (APC -1.6%, 95% CI -2.1% to -1.1%). Significant differences in mortality and changes in trends over time were observed in non-Hispanic blacks, Hispanics, and non-Hispanic Asians. DISCUSSION: In this analysis of nationally representative data, changing mortality trends in various biliary tract cancers was noted with a disproportionately higher burden of fatality in minorities.

Occult Pathologic Findings in Reduction Mammaplasty in 5781 Patients-An International Multicenter Study.

Breast cancer is among the most commonly diagnosed cancers in the world, affecting one in eight women in their lifetimes. The disease places a substantial burden on healthcare systems in developed countries and often requires surgical correction. In spite of this, much of the breast cancer pathophysiology remains unknown, allowing for the cancer to develop to later stages prior to detection. Many women undergo reduction mammaplasties (RM) to adjust breast size, with over 500,000 operations being performed annually. Tissue samples from such procedures have drawn interest recently, with studies attempting to garner a better understanding of breast cancer's development. A number of samples have revealed nascent cancer developments that were previously undetected and unexpected. Investigating these so-called "occult" findings of cancer in otherwise healthy patients may provide further insight regarding risk factors and countermeasures. Here, we detail occult findings of cancer in reduction mammaplasty samples provided from a cohort of over 5000 patients from 16 different institutions in Europe. Although the majority of our resected breast tissue specimens were benign, our findings indicate that there is a continued need for histopathological examination. As a result, our study suggests that preoperative imaging should be routinely performed in patients scheduled for RM, especially those with risk factors of breast cancer, to identify and enable a primary oncologic approach.