DYNC2H1 hypomorphic or retina-predominant variants cause nonsyndromic retinal degeneration

Purpose: Determining the role of DYNC2H1 variants in nonsyndromic inherited retinal disease (IRD). Methods: Genome and exome sequencing were performed for five unrelated cases of IRD with no identified variant. In vitro assays were developed to validate the variants identified (fibroblast assay, induced pluripotent stem cell [iPSC] derived retinal organoids, and a dynein motility assay). Results: Four novel DYNC2H1 variants (V1, g.103327020_103327021dup; V2, g.103055779A>T; V3, g.103112272C>G; V4, g.103070104A>C) and one previously reported variant (V5, g.103339363T>G) were identified. In proband 1 (V1/V2), V1 was predicted to introduce a premature termination codon (PTC), whereas V2 disrupted the exon 41 splice donor site causing incomplete skipping of exon 41. V1 and V2 impaired dynein-2 motility in vitro and perturbed IFT88 distribution within cilia. V3, homozygous in probands 2–4, is predicted to cause a PTC in a retina-predominant transcript. Analysis of retinal organoids showed that this new transcript expression increased with organoid differentiation. V4, a novel missense variant, was in trans with V5, previously associated with Jeune asphyxiating thoracic dystrophy (JATD). Conclusion: The DYNC2H1 variants discussed herein were either hypomorphic or affecting a retina-predominant transcript and caused nonsyndromic IRD. Dynein variants, specifically DYNC2H1 variants are reported as a cause of non syndromic IRD

Antiphospholipid antibodies and cerebral artery dissection: two frequent causes of brain ischemia in young adults.

As part of a multicenter study on ischemic stroke in the young, we report the occurrence of high antiphospholipid antibody (aPLs) levels and cerebral dissection in 75 patients. These represent the two most frequent non-thromboembolic causes of cerebral ischemia in our population. Increased aPL titres were found in nine cases (12%); cerebral artery dissection in eleven (14%). Our data stress the need to modify the classical diagnostic approach to cerebral ischemia by including hematological assessments and new neuroimaging techniques as screening tests

Isolation and characterization of a spontaneously immortalized multipotent mesenchymal cell line derived from mouse subcutaneous adipose tissue

The emerging field of tissue engineering and regenerative medicine is a multidisciplinary science that is based on the combination of a reliable source of stem cells, biomaterial scaffolds, and cytokine growth factors. Adult mesenchymal stem cells are considered important cells for applications in this field, and adipose tissue has revealed to be an excellent source of them. Indeed, adipose-derived stem cells (ASCs) can be easily isolated from the stromal vascular fraction (SVF) of adipose tissue. During the isolation and propagation of murine ASCs, we observed the appearance of a spontaneously immortalized cell clone, named m17.ASC. This clone has been propagated for more than 180 passages and stably expresses a variety of stemness markers, such as Sca-1, c-kit/CD117, CD44, CD106, islet-1, nestin, and nucleostemin. Furthermore, these cells can be induced to differentiate toward osteogenic, chondrogenic, adipogenic, and cardiogenic phenotypes. m17.ASC clone displays a normal karyotype and stable telomeres; it neither proliferates when plated in soft agar nor gives rise to tumors when injected subcutaneously in NOD/SCID-\u3b3 null mice. The analysis of gene expression highlighted transcriptional traits of SVF cells. m17.ASCs were genetically modified by lentiviral vectors carrying green fluorescent protein (GFP) as a marker transgene and efficiently engrafted in the liver, when injected in the spleen of NOD/SCID-\u3b3 null monocrotaline-treated mice. These results suggest that this non-tumorigenic spontaneously immortalized ASC line may represent a useful tool (cell model) for studying the differentiation mechanisms involved in tissue repair as well as a model for pharmacological/toxicological studies