Robotic Habitat Technologies for Minimizing Crew Maintenance Requirements

NASA’s Lunar Gateway aims to be deployed later in the decade and will serve as an outpost orbiting the moon. This habitat will be utilized as a base for lunar operations as well as future missions to Mars. Unlike the International Space Station (ISS), which maintains three to six astronauts at any given time, the Lunar Gateway will be uncrewed for eleven months out of the year. Over 80% of crew time onboard the ISS is dedicated to logistics, repair, and maintenance, leaving minimal time for scientific research and experimentation. In order to maintain Gateway, robotic systems must be implemented to accomplish maintenance and operational tasks. This paper discusses our team’s proposed dexterous robotic system, which will address routine and contingency operational and maintenance tasks on Gateway. The project is experimentally-based, and split into three approaches: cataloging robotic capabilities via robot/taskboard interactions, logistics management of Cargo Transfer Bags (CTBs), and software development of an AprilTag situational development system. This research project utilizes the unique capabilities of the University of Maryland (UMD) Space Systems Laboratory (SSL), which houses various dexterous robotic manipulators, mock-ups of space habitats, and the Neutral Buoyancy Research Facility (NBRF), a 50-foot diameter, 25-foot deep water tank used to simulate microgravity conditions. By incorporating robotic systems into the architecture of the Lunar Gateway, it will allow for the lunar outpost to be continually operated and maintained while uncrewed, and will allow for astronauts, when present, to focus on maximizing scientific discoveries.NASA RASC-AL 202

Systematic Comparison of Retinal Organoid Differentiation from Human Pluripotent Stem Cells Reveals Stage Specific, Cell Line, and Methodological Differences

A major goal in the stem cell field is to generate tissues that can be utilized as a universal tool for in vitro models of development and disease, drug development, or as a resource for patients suffering from disease or injury. Great efforts are being made to differentiate human pluripotent stem cells in vitro toward retinal tissue, which is akin to native human retina in its cytoarchitecture and function, yet the numerous existing retinal induction protocols remain variable in their efficiency and do not routinely produce morphologically or functionally mature photoreceptors. Herein, we determine the impact that the method of embryoid body (EB) formation and maintenance as well as cell line background has on retinal organoid differentiation from human embryonic stem cells and human induced pluripotent stem cells. Our data indicate that cell line‐specific differences dominate the variables that underline the differentiation efficiency in the early stages of differentiation. In contrast, the EB generation method and maintenance conditions determine the later differentiation and maturation of retinal organoids. Of the latter, the mechanical method of EB generation under static conditions, accompanied by media supplementation with Y27632 for the first 48 hours of differentiation, results in the most consistent formation of laminated retinal neuroepithelium containing mature and electrophysiologically responsive photoreceptors. Collectively, our data provide substantive evidence for stage‐specific differences in the ability to give rise to laminated retinae, which is determined by cell line‐specific differences in the early stages of differentiation and EB generation/organoid maintenance methods at later stages

ROBOTIC TECHNOLOGIES FOR MINIMIZING CREW MAINTENANCE REQUIREMENTS IN SPACE HABITATS

Gemstone Team ASTROThe International Space Station (ISS) is crewed continuously by astronauts conducting scientifc research in microgravity. However, their work is not limited to scientifc research alone; in fact, logistics, maintenance, and repair tasks on the ISS require more than 80% of available crew time, severely limiting opportunities for performing scientifc experiments and technological development. NASA is planning a new project known as Gateway (also referred to as the Lunar Orbital Platform-Gateway). This station will orbit the Moon and be uncrewed for 11 months per year. Astronauts will only be present in the outpost for a limited period of time and will not always be available for continuous repairs and maintenance, as is required for Gateway to operate. Therefore, robotic system(s) are necessary to regularly accomplish these tasks both in the absence and presence of astronauts. Throughout this project, Team ASTRO (Assessment of Space Technologies for Robotic Operations) explored the feasibility of integrating dexterous robotic systems in space habitat architectures to perform routine and contingency operational and maintenance tasks. Ultimately, this allows for astronauts, when present, to focus on exploration and scientifc discoveries. The team conducted this research through three approaches: Gateway component analog taskboard development and end e˙ector assessment, Cargo Transfer Bag (CTB) manipulation and logistics, and AprilTag situational awareness simulation development. Based on analyses and experimental results gained from this research, the team found that robotic systems are feasible alternatives for space habitat operation. Team ASTRO also determined that AprilTags can be used for optimization of the Gateway design to facilitate uncrewed operations and robotic servicing to improve crew productivity when present

SARS-CoV-2 entry factors are highly expressed in nasal epithelial cells together with innate immune genes.

We investigated SARS-CoV-2 potential tropism by surveying expression of viral entry-associated genes in single-cell RNA-sequencing data from multiple tissues from healthy human donors. We co-detected these transcripts in specific respiratory, corneal and intestinal epithelial cells, potentially explaining the high efficiency of SARS-CoV-2 transmission. These genes are co-expressed in nasal epithelial cells with genes involved in innate immunity, highlighting the cells' potential role in initial viral infection, spread and clearance. The study offers a useful resource for further lines of inquiry with valuable clinical samples from COVID-19 patients and we provide our data in a comprehensive, open and user-friendly fashion at www.covid19cellatlas.org.This work was supported by the Wellcome Sanger Institute core funding (WT206194) and the Wellcome Strategic Scientific Support award “Pilot projects for the Human Cell Atlas” (WT211276/Z/18/Z), a Seed Network grant from the Chan Zuckerberg Initiative to P.B., T.D., T.E.D., O.E., P.H., N.H., N.K., M.K., K.B.M., A.M., M.C.N., M.N., D.P., J.R., P.R.T., S.Q., A.R., O.R., M.S., J.S., J.G.S., C.E.S., H.B.S., D.S., A.T., J.W. and K.Z. and by the European Union’s H2020 research and innovation program under grant agreement No 874656 (discovAIR) to P.B., A.B., M.K., S.L., J.L., K.B.M., M.C.N., K.S.P., C.S., H.B.S., J.S., F.J.T. and M.vd.B. W.S. acknowledges funding from the Newton Fund, Medical Research Council (MRC), The Thailand Research Fund (TRF), and Thailand’s National Science and Technology Development Agency (NSTDA). M.C.N acknowledges funding from GSK Ltd, Netherlands Lung Foundation project no. 5.1.14.020 and 4.1.18.226. T.D. acknowledges funding from HubMap consortium and Stanford Child Health Research Institute- Woods Family Faculty Scholarship. T.E.D. acknowledges funding from HubMap. P.H. acknowledges funding from LENDULET-BIOMAG Grant (2018-342) and the European Regional Development Funds (GINOP-2.3.2-15-2016-00006, GINOP-2.3.2-15-2016-00026, GINOP-2.3.2-15-2016-00037). J.L.B. acknowledges funding from Medical Research Council (MRC), and the UK Regenerative Medicine Platform (MR/ 5005579/1). P.B. acknowledges funding from Fondation pour la Recherche Médicale (DEQ20180339158), Agence Nationale de la Recherche (UCAJEDI, ANR-15-IDEX-01; SAHARRA, ANR-19-CE14-0027; France Génomique, ANR-10-INBS-09-03), and Conseil Départemental des Alpes Maritimes (2016-294DGADSH-CV; 2019-390DGADSH-CV). N.E.B. and J.K. acknowledge funding from NIH grant R01HL145372 and DOD grant W81XWH1910416. I.G. acknowledges funding from NIH (5R24HD000836) and the Eunice Kennedy Shriver National Institute of Child Health and Human. N.H., J.G.S. and C.E.S. acknowledge funding by the Leducq foundation. N.H. is recipient of an ERC Advanced Grant. J.K. acknowledges funding from NIH grant K08HL130595 and the Doris Duke Charitable Foundation. N.K. acknowledges funding from NIH grants R01HL127349, U01HL145567 and an unrestricted grant from Three Lakes Foundation. M.K. acknowledges HHMI and Wall Center for Pulmonary Vascular Disease. H.L. acknowledges funding from National Research Foundation of Korea. K.M. acknowledges funding from Wellcome Trust. A.M. acknowledges funding from NIH grants HL135124, AG049665 and AI135964. M.Z.N. acknowledges funding from Rutherford Fund Fellowship allocated by the Medical Research Council and the UK Regenerative Medicine Platform (MR/ 5005579/1 to M.Z.N.). M.Z.N. and M.Y. have been funded by the Rosetrees Grant (Grant number M899). M.N. acknowledges funding from a BHF/DZHK grant and British Heart Foundation (PG/16/47/32156). J.O.-M. acknowledges funding from Richard and Susan Smith Family Foundation. D.P. acknowledges funding from Alan and Sandra Gerry Metastasis and Tumor Ecosystems Center. J.P. acknowledges funding from National Health and Medical Research Council. P.R.T. acknowledges funding from R01HL146557 from NHLBI/NIH. E.L.R. acknowledges funding from MRC MR/P009581/1 and MR/SO35907/1. A.R. and O. R. acknowledge HHMI, the Klarman Cell Observatory, and the Manton Foundation. K.S.-P. acknowledges NIHR Cambridge Biomedical Research Centre. C.S. acknowledges Swedish research Council, Swedish Cancer Society, and CPI. H.B.S. acknowledges German Center for Lung Research and Helmholtz Association. J.S. acknowledges Boehringer Ingelheim, by the German Research Foundation (DFG; EXC2151/1, ImmunoSensation2 - the immune sensory system, project number 390873048), project numbers 329123747, 347286815) and by the HGF grant sparse2big. A.K.S. acknowledges the Beckman Young Investigator Program, a Sloan Fellowship in Chemistry, the NIH (5U24AI118672), and the Bill and Melinda Gates Foundation. F.J.T. acknowledges the German Center for Lung Research. M.vd.B. acknowledges from Ministry of Economic Affairs and Climate Policy by means of the PPP. K.B.W. is funded by the University College London-Birkbeck MRC Doctoral Training Programme. J.W. and Y.Y. acknowledge NIH, U01 HL148856 LungMap Phase II. R.X. acknowledges the NIH (DK043351). H.Z. is supported by the National Key R&D Program (no. 2019YFA0801703) and National Natural Science Foundation of China (no. 31871370

Human Retinal Organoids Provide a Suitable Tool for Toxicological Investigations: a Comprehensive Validation Using Drugs and Compounds Affecting the Retina

Retinal drug toxicity screening is essential for the development of safe treatment strategies for a large number of diseases. To this end, retinal organoids derived from human pluripotent stem cells (hPSCs) provide a suitable screening platform due to their similarity to the human retina and the ease of generation in large-scale formats. In this study, two hPSC cell lines were differentiated to retinal organoids, which comprised all key retinal cell types in multiple nuclear and synaptic layers. Single-cell RNA-Seq of retinal organoids indicated the maintenance of retinal ganglion cells and development of bipolar cells: both cell types segregated into several subtypes. Ketorolac, digoxin, thioridazine, sildenafil, ethanol, and methanol were selected as key compounds to screen on retinal organoids because of their well-known retinal toxicity profile described in the literature. Exposure of the hPSC-derived retinal organoids to digoxin, thioridazine, and sildenafil resulted in photoreceptor cell death, while digoxin and thioridazine additionally affected all other cell types, including Müller glia cells. All drug treatments caused activation of astrocytes, indicated by dendrites sprouting into neuroepithelium. The ability to respond to light was preserved in organoids although the number of responsive retinal ganglion cells decreased after drug exposure. These data indicate similar drug effects in organoids to those reported in in vivo models and/or in humans, thus providing the first robust experimental evidence of their suitability for toxicological studies

Incorporating microglia‐like cells in human induced pluripotent stem cell‐derived retinal organoids

Microglia are the primary resident immune cells in the retina. They regulate neuronal survival and synaptic pruning making them essential for normal development. Following injury, they mediate adaptive responses and under pathological conditions they can trigger neurodegeneration exacerbating the effect of a disease. Retinal organoids derived from human induced pluripotent stem cells (hiPSCs) are increasingly being used for a range of applications, including disease modelling, development of new therapies and in the study of retinogenesis. Despite many similarities to the retinas developed in vivo, they lack some key physiological features, including immune cells. We engineered an hiPSC co-culture system containing retinal organoids and microglia-like (iMG) cells and tested their retinal invasion capacity and function. We incorporated iMG into retinal organoids at 13 weeks and tested their effect on function and development at 15 and 22 weeks of differentiation. Our key findings showed that iMG cells were able to respond to endotoxin challenge in monocultures and when co-cultured with the organoids. We show that retinal organoids developed normally and retained their ability to generate spiking activity in response to light. Thus, this new co-culture immunocompetent in vitro retinal model provides a platform with greater relevance to the in vivo human retina

PRPF8-mediated dysregulation of hBrr2 helicase disrupts human spliceosome kinetics and 5´-splice-site selection causing tissue-specific defects.

The carboxy-terminus of the spliceosomal protein PRPF8, which regulates the RNA helicase Brr2, is a hotspot for mutations causing retinitis pigmentosa-type 13, with unclear role in human splicing and tissue-specificity mechanism. We used patient induced pluripotent stem cells-derived cells, carrying the heterozygous PRPF8 c.6926 A > C (p.H2309P) mutation to demonstrate retinal-specific endophenotypes comprising photoreceptor loss, apical-basal polarity and ciliary defects. Comprehensive molecular, transcriptomic, and proteomic analyses revealed a role of the PRPF8/Brr2 regulation in 5'-splice site (5'SS) selection by spliceosomes, for which disruption impaired alternative splicing and weak/suboptimal 5'SS selection, and enhanced cryptic splicing, predominantly in ciliary and retinal-specific transcripts. Altered splicing efficiency, nuclear speckles organisation, and PRPF8 interaction with U6 snRNA, caused accumulation of active spliceosomes and poly(A)+ mRNAs in unique splicing clusters located at the nuclear periphery of photoreceptors. Collectively these elucidate the role of PRPF8/Brr2 regulatory mechanisms in splicing and the molecular basis of retinal disease, informing therapeutic approaches

Differential IRF8 Transcription Factor Requirement Defines Two Pathways of Dendritic Cell Development in Humans

The formation of mammalian dendritic cells (DCs) is controlled by multiple hematopoietic transcription factors, including IRF8. Loss of IRF8 exerts a differential effect on DC subsets, including plasmacytoid DCs (pDCs) and the classical DC lineages cDC1 and cDC2. In humans, cDC2-related subsets have been described including AXL+ SIGLEC6+ pre-DC, DC2 and DC3. The origin of this heterogeneity is unknown. Using highdimensional analysis, in vitro differentiation, and an allelic series of human IRF8 deficiency, we demonstrated that cDC2 (CD1c+ DC) heterogeneity originates from two distinct pathways of development. The lymphoidprimed IRF8hi pathway, marked by CD123 and BTLA, carried pDC, cDC1, and DC2 trajectories, while the common myeloid IRF8lo pathway, expressing SIRPA, formed DC3s and monocytes. We traced distinct trajectories through the granulocyte-macrophage progenitor (GMP) compartment showing that AXL+ SIGLEC6+ pre-DCs mapped exclusively to the DC2 pathway. In keeping with their lower requirement for IRF8, DC3s expand to replace DC2s in human partial IRF8 deficiency

Retinal pigment epithelium extracellular vesicles are potent inducers of age‐related macular degeneration disease phenotype in the outer retina

Age-related macular degeneration (AMD) is a leading cause of blindness. Vision loss is caused by the retinal pigment epithelium (RPE) and photoreceptors atrophy and/or retinal and choroidal angiogenesis. Here we use AMD patient-specific RPE cells with the Complement Factor H Y402H high-risk polymorphism to perform a comprehensive analysis of extracellular vesicles (EVs), their cargo and role in disease pathology. We show that AMD RPE is characterised by enhanced polarised EV secretion. Multi-omics analyses demonstrate that AMD RPE EVs carry RNA, proteins and lipids, which mediate key AMD features including oxidative stress, cytoskeletal dysfunction, angiogenesis and drusen accumulation. Moreover, AMD RPE EVs induce amyloid fibril formation, revealing their role in drusen formation. We demonstrate that exposure of control RPE to AMD RPE apical EVs leads to the acquisition of AMD features such as stress vacuoles, cytoskeletal destabilization and abnormalities in the morphology of the nucleus. Retinal organoid treatment with apical AMD RPE EVs leads to disrupted neuroepithelium and the appearance of cytoprotective alpha B crystallin immunopositive cells, with some co-expressing retinal progenitor cell markers Pax6/Vsx2, suggesting injury-induced regenerative pathways activation. These findings indicate that AMD RPE EVs are potent inducers of AMD phenotype in the neighbouring RPE and retinal cells

Health, education, and social care provision after diagnosis of childhood visual disability

Aim: To investigate the health, education, and social care provision for children newly diagnosed with visual disability.Method: This was a national prospective study, the British Childhood Visual Impairment and Blindness Study 2 (BCVIS2), ascertaining new diagnoses of visual impairment or severe visual impairment and blindness (SVIBL), or equivalent vi-sion. Data collection was performed by managing clinicians up to 1-year follow-up, and included health and developmental needs, and health, education, and social care provision.Results: BCVIS2 identified 784 children newly diagnosed with visual impairment/SVIBL (313 with visual impairment, 471 with SVIBL). Most children had associated systemic disorders (559 [71%], 167 [54%] with visual impairment, and 392 [84%] with SVIBL). Care from multidisciplinary teams was provided for 549 children (70%). Two-thirds (515) had not received an Education, Health, and Care Plan (EHCP). Fewer children with visual impairment had seen a specialist teacher (SVIBL 35%, visual impairment 28%, χ2p < 0.001), or had an EHCP (11% vs 7%, χ2p < 0 . 01).Interpretation: Families need additional support from managing clinicians to access recommended complex interventions such as the use of multidisciplinary teams and educational support. This need is pressing, as the population of children with visual impairment/SVIBL is expected to grow in size and complexity.This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited