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InS2 is Cubic Laves structured and crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. In3+ is bonded in a 12-coordinate geometry to twelve equivalent S+1.50- atoms. All In–S bond lengths are 3.33 Å. S+1.50- is bonded to six equivalent In3+ and six equivalent S+1.50- atoms to form a mixture of face, edge, and corner-sharing SIn6S6 cuboctahedra. All S–S bond lengths are 2.84 Å.
Single cell RNA sequencing (scRNA-Seq) technologies have greatly enhanced our understanding of islet cell transcriptomes and have revealed the existence of ß cell heterogeneity. However, comparison of scRNA-Seq datasets from different groups have highlighted inconsistencies in gene expression patterns, primarily due to variable detection of lower abundance transcripts. Furthermore, such analyses are unable to uncover the spatial organization of heterogeneous gene expression. Here we used fluctuation localization imaging-based fluorescence in situ hybridization (fliFISH) to quantify transcripts in single cells in mouse pancreatic islet sections. We compared the expression patterns of Insulin 2 (Ins2) with Mafa and Ucn3 – two genes expressed in ß cells as they mature, as well as Rgs4 – a factor with variably reported expression in the islet. This approach accurately quantified transcripts across a wide range of expression levels - from single copies to over hundred copies per cell in one islet. Importantly, fliFISH allowed evaluation of transcript heterogeneity in the spatial context of an intact islet. These studies confirm the existence of a high degree of heterogeneous gene expression levels within the islet and highlight relative and radial expression patterns that likely reflect distinct ß cell maturation states along the radial axis of the islet.
Purpose: We tested the hypothesis that loss of angiotensin converting enzyme 2 (ACE2) within diabetic HS/PCs (Hematopoietic Stem/Progenitor Cells) would be detrimental to HS/PC reparative function, and alter their ability to contribute to vascular remodeling in human subjects and rodent models of DR (Diabetic Retinopathy). Methods: Subjects (n52) were recruited as controls (n13) or diabetics (n39) with either no DR, mild non-proliferative DR (NPDR), moderate NPDR, severe NPDR or proliferative DR (PDR). Fluorescein angiograms were analyzed using Vessel Generation Analysis (VESGEN) software in a cohort of subjects. CD34+ HS/PCs were isolated from peripheral blood. RAS (Renin-Angiotensin System) gene expression and migration was measured. Diabetic ACE2 knockout (KO)C57BL6-Ins2 (Akita) mice at 3, 6 and 9 months of diabetes were compared to age-matched controls. Bone marrow HS/PC populations were analyzed by flow cytometry and migration and proliferation studies performed. Results: ACE2 gene expression in human CD34+ cells from diabetics without DR was increased compared to controls (p0.0437). Mas receptor mRNA was also increased in diabetics without DR, but reduced with the onset of NPDR (p0.0002), suggesting a loss of compensation. DR was associated with CD34+ cell migratory dysfunction. By VESGEN analysis, vessel density measured by several confirming parameters in early NPDR (n3) was greater than in normal retina (n6) in both arteries and veins, which suggests active retinal remodeling. ACE2KO-Akita and Akita cohorts showed reduced retinal thickness by OCT (Optical Coherence Tomography) at 9 months of diabetes. Absence of ACE2 in 9-month Akita mice led to an accelerated increase in acellular capillaries compared to diabetic alone. Electroretinogram (ERG) in ACE2KO-Akita mice resulted in persistent deterioration of the neural retina. Reparative function studies showed that ACE2KO exacerbated diabetes-induced impairment of LK (Low Potassium) cell migration and proliferative functions as early as 3-month of diabetes (p0.0019). Conclusions: Retinopathy and adverse vascular remodeling in subjects with diabetes was associated with a loss of the protective arm of RAS in HS/PCs. Loss of ACE2 exacerbated vascular dysfunction in diabetic mice.