Orthogonally induced differentiation of stem cells for the programmatic patterning of vascularized organoids and bioprinted tissues.

The generation of organoids and tissues with programmable cellular complexity, architecture and function would benefit from the simultaneous differentiation of human induced pluripotent stem cells (hiPSCs) into divergent cell types. Yet differentiation protocols for the overexpression of specific transcription factors typically produce a single cell type. Here we show that patterned organoids and bioprinted tissues with controlled composition and organization can be generated by simultaneously co-differentiating hiPSCs into distinct cell types via the forced overexpression of transcription factors, independently of culture-media composition. Specifically, we used such orthogonally induced differentiation to generate endothelial cells and neurons from hiPSCs in a one-pot system containing either neural or endothelial stem-cell-specifying media, and to produce vascularized and patterned cortical organoids within days by aggregating inducible-transcription-factor and wild-type hiPSCs into randomly pooled or multicore-shell embryoid bodies. Moreover, by leveraging multimaterial bioprinting of hiPSC inks without extracellular matrix, we generated patterned neural tissues with layered regions composed of neural stem cells, endothelium and neurons. Orthogonally induced differentiation of stem cells may facilitate the fabrication of engineered tissues for biomedical applications.

Geographical Differences in Cardiovascular Comorbidities and Outcomes of COVID-19 Hospitalized Patients in the USA.

INTRODUCTION: Cardiovascular comorbidities may predispose to adverse outcomes in hospitalized patients with coronavirus disease 2019 (COVID-19). However, across the USA, the burden of cardiovascular comorbidities varies significantly. Whether clinical outcomes of hospitalized patients with COVID-19 differ between regions has not yet been studied systematically. Here, we report differences in underlying cardiovascular comorbidities and clinical outcomes of patients hospitalized with COVID-19 in Texas and in New York state. METHODS: We established a multicenter retrospective registry including patients hospitalized with COVID-19 between March 15 and July 12, 2020. Demographic and clinical data were manually retrieved from electronic medical records. We focused on the following outcomes: mortality, need for pharmacologic circulatory support, need for mechanical ventilation, and need for hemodialysis. Univariate and multivariate logistic regression analyses were performed. RESULTS: Patients in the Texas cohort (n = 296) were younger (57 vs. 63 years, p value <0.001), they had a higher BMI (30.3 kg/m2 vs. 28.5 kg/m2, p = 0.015), and they had higher rates of diabetes mellitus (41 vs. 30%; p = 0.014). In contrast, patients in the New York state cohort (n = 218) had higher rates of coronary artery disease (19 vs. 10%, p = 0.005) and atrial fibrillation (11 vs. 5%, p = 0.012). Pharmacologic circulatory support, mechanical ventilation, and hemodialysis were more frequent in the Texas cohort (21 vs. 13%, p = 0.020; 30 vs. 12%, p < 0.001; and 11 vs. 5%, p = 0.009, respectively). In-hospital mortality was similar between the 2 cohorts (16 vs. 18%, p = 0.469). After adjusting for differences in underlying comorbidities, only the use of mechanical ventilation remained significantly higher in the participating Texas hospitals (odds ratios [95% CI]: 3.88 [1.23, 12.24]). Median time to pharmacologic circulatory support was 8 days (interquartile range: 2, 13.8) in the Texas cohort compared to 1 day (0, 3) in the New York state cohort, while median time to in-hospital mortality was 16 days (10, 25.5) and 7 days (4, 14), respectively (both p < 0.001). In-hospital mortality was higher in the late versus the early study phase in the New York state cohort (24 vs. 14%, p = 0.050), while it was similar between the 2 phases in the Texas cohort (16 vs. 15%, p = 0.741). CONCLUSIONS: Geographical differences, including practice pattern variations and the impact of disease burden on provision of health care, are important for the evaluation of COVID-19 outcomes. Unadjusted data may cause bias affecting future regulatory policies and proper allocation of resources.

Biomanufacturing of organ-specific tissues with high cellular density and embedded vascular channels.

Engineering organ-specific tissues for therapeutic applications is a grand challenge, requiring the fabrication and maintenance of densely cellular constructs composed of ~108 cells/ml. Organ building blocks (OBBs) composed of patient-specific-induced pluripotent stem cell-derived organoids offer a pathway to achieving tissues with the requisite cellular density, microarchitecture, and function. However, to date, scant attention has been devoted to their assembly into 3D tissue constructs. Here, we report a biomanufacturing method for assembling hundreds of thousands of these OBBs into living matrices with high cellular density into which perfusable vascular channels are introduced via embedded three-dimensional bioprinting. The OBB matrices exhibit the desired self-healing, viscoplastic behavior required for sacrificial writing into functional tissue (SWIFT). As an exemplar, we created a perfusable cardiac tissue that fuses and beats synchronously over a 7-day period. Our SWIFT biomanufacturing method enables the rapid assembly of perfusable patient- and organ-specific tissues at therapeutic scales.

Cardiac sarcoidosis presenting as arrhythmogenic right ventricular cardiomyopathy/dysplasia with ventricular aneurysms: a case report.

A 70-year old Caucasian man with recurrent ventricular tachycardia and progressive biventricular failure attributed to arrhythmogenic right ventricular cardiomyopathy/dysplasia was evaluated for heart transplantation. Cardiac ventriculography revealed an abnormal left ventricle with five saccular aneurysms. Heart transplantation was performed. Pathology of the explanted heart showed multifocal sarcoid granulomas. Replacement fibrosis was widespread in both ventricles and associated with saccular aneurysms. No genetic basis was identified. Thus, the evidence suggested progressive cardiac sarcoidosis caused this patient's unusual condition.