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This study aims to present an easily scalable, cost-efficient process of dECM extraction from porcine meniscus, dedicated to bioink preparation and 3D bioprinting. Due to its cartilage like structure and mechanical robustness, the meniscus is an exceptionally demanding tissue for extraction and decellularisation of its ECM. Its processing poses a great difficulty and renders the methods previously developed for soft tissues useless. A process, combining homogenisation, hydrolysis, supercritical CO2 (scCO2) extraction and lyophilisation, was developed to meet this challenge. This protocol allows for retaining its native compounds and biocompatibility while offering good printability and providing a stimulatory environment for cell proliferation and differentiation towards a meniscus-like phenotype. Also, this process is economically and ecologically friendly since it doesn't require the use of high amounts of solvents, detergents or expensive enzymes (DNase). The decellularisation process has been meticulously studied, demonstrating a substantial reduction in DNA content but still exceeding accepted thresholds. The study further explores the biocompatibility of the dECM, demonstrating no detrimental effects of remnant DNA on cell survival during extended in vitro culture, indicating excellent biocompatibility. These findings challenge the current definition of decellularisation effectiveness based solely on DNA content, proposing a broader assessment of biological effects.

Abstract Articular cartilage and meniscus injuries are prevalent disorders with insufficient regeneration responses offered by available treatment methods. In this regard, 3D bioprinting has emerged as one of the most promising new technologies, offering novel treatment options. Additionally, the latest achievements from the fields of biomaterials and tissue engineering research identified constituents facilitating the creation of biocompatible scaffolds. In this study, we looked closer at hyaluronic acid and multi-walled carbon nanotubes as bioink additives. Firstly, we assessed the minimal concentrations that stimulate cell viability, and decrease reactive oxygen species and apoptosis levels in 2D cell cultures of normal human knee articular chondrocytes (NHAC) and human adipose-derived mesenchymal stem cells (hMSC-AT). In this regard, 0.25 mg/ml of hyaluronic acid and 0.0625 mg/ml of carbon nanotubes were selected as the most optimal concentrations. In addition, we investigated the protective influence of 2-phospho-L-ascorbic acid in samples with carbon nanotubes. Tests conducted on 3D bioprinted constructs revealed that only a combination of components positively impacted cell viability throughout the whole experiment. Gene expression analysis of COL1A1, COL6A1, HIF1A, COMP, RUNX2, and POU5F1 showed significant changes in the expression of all analyzed genes with a progressive overall loss of transcriptional activity in most of them.

The integration of artificial neuromorphic devices with biological systems plays a fundamental role for future brain-machine interfaces, prosthetics, and intelligent soft robotics. Harikesh et al. demonstrate all-printed organic electrochemical neurons on Venus flytrap that is controlled to open and close.

Kidneys from non-white donors have inferior outcomes, but it is unclear if ethnicity matching between donors and recipients achieves better post kidney transplant outcomes.We undertook a retrospective, population cohort study utilising UK Transplant Registry data. The cohort comprised adult, kidney-alone, transplant recipients receiving their first kidney transplant between 2003-2015, with data censored at 1st October 2016. We included 27,970 recipients stratified into white (n = 23,215), black (n = 1,679) and south Asian (n = 3,076) ethnicity, with median post-transplant follow-up of 1,676 days (IQR 716-2,869 days). Unadjusted and adjusted Cox regression survival analyses were performed to investigate ethnicity effect on risk for graft loss and mortality.In unadjusted analyses, matched ethnicity between donors-recipients resulted in better outcomes for delayed graft function, one-year creatinine, graft and patient survival but these differed by ethnicity matches. Compared to white-to-white transplants, risk for death-censored graft loss was higher in black-to-black and similar among Asian-to-Asian transplants, but mortality risk was lower for both black-to-black and Asian-to-Asian transplants. In Cox regression models, compared to white donors, we observed higher risk for graft loss with both south Asian (HR 1.38, 95%CI 1.12-1.70, p = 0.003) and black (HR 1.66, 95%CI 1.30-2.11, p

Genetic interaction mapping is useful for understanding the molecular basis of cellular decision making, but elucidating interactions genome-wide is challenging due to the massive number of gene combinations that must be tested. Here, we demonstrate a simple approach to thoroughly map genetic interactions in bacteria using microfluidic-based single cell sequencing. Using single cell PCR in droplets, we link distinct genetic information into single DNA sequences that can be decoded by next generation sequencing. Our approach is scalable and theoretically enables the pooling of entire interaction libraries to interrogate multiple pairwise genetic interactions in a single culture. The speed, ease, and low-cost of our approach makes genetic interaction mapping viable for routine characterization, allowing the interaction network to be used as a universal read out for a variety of biology experiments, and for the elucidation of interaction networks in non-model organisms.

The mechanism underlying the excess risk of non-AIDS diseases among HIV infected people is unclear. HIV associated inflammation/hypercoagulability likely plays a role. While antiretroviral therapy (ART) may return this process to pre-HIV levels, this has not been directly demonstrated. We analyzed data/specimens on 249 HIV+ participants from the US Military HIV Natural History Study, a prospective, multicenter observational cohort of >5600 active duty military personnel and beneficiaries living with HIV. We used stored blood specimens to measure D-dimer and Interleukin-6 (IL-6) at three time points: pre-HIV seroconversion, ≥6 months post-HIV seroconversion but prior to ART initiation, and ≥6 months post-ART with documented HIV viral suppression on two successive evaluations. We evaluated the changes in biomarker levels between time points, and the association between these biomarker changes and future non-AIDS events. During a median follow-up of 3.7 years, there were 28 incident non-AIDS diseases. At ART initiation, the median CD4 count was 361cells/mm3; median duration of documented HIV infection 392 days; median time on ART was 354 days. Adjusted mean percent increase in D-dimer levels from pre-seroconversion to post-ART was 75.1% (95% confidence interval 24.6-148.0, p = 0.002). This increase in D-dimer was associated with a significant 22% increase risk of future non-AIDS events (p = 0.03). Changes in IL-6 levels across time points were small and not associated with future non-AIDS events. In conclusion, ART initiation and HIV viral suppression does not eliminate HIV associated elevation in D-dimer levels. This residual pathology is associated with an increased risk of future non-AIDS diseases.