Early transcriptional changes linked to naturally occurring Huntington's disease mutations in neural derivatives of human embryonic stem cells

Abstract

Huntington's disease (HD) is characterized by a late clinical onset despite ubiquitous expression of the mutant gene at all developmental stages. How mutant huntingtin impacts on signalling pathways in the pre-symptomatic period has remained essentially unexplored in humans due to a lack of appropriate models. Using multiple human embryonic stem cell lines derived from blastocysts diagnosed as carrying the mutant huntingtin gene by pre-implantation genetic diagnosis, we explored early developmental changes in gene expression using differential transcriptomics, combined with gain and loss of function strategies. We demonstrated a down-regulation of the HTT gene itself in HD neural cells and identified three genes, the expression of which differs significantly in HD cells when compared with wild-type controls, namely CHCHD2, TRIM4 and PKIB. Similar dysregulation had been observed previously for CHCDH2 and TRIM4 in blood cells from patients. CHCHD2 is involved in mitochondrial function and PKIB in protein kinase A-dependent pathway regulation, which suggests that these functions may be precociously impacted in HD.

A 3D printed microfluidic device for production of functionalized hydrogel microcapsules for culture and differentiation of human Neuronal Stem Cells (hNSC)

“…These cells were derived from the BC1 hIPSCs line obtained from MTI-Globalstem using a previously published protocol. 19 Encapsulation was performed by adding 25% Matrigel to the cell suspension as described in the previous section. NSCs survival was assessed by fluorescence microscopy using classical viability dyes.…”

“…All these protocols require a lamininrich coating. 19 Thanks to our new cell culture container, we have been able to simply transfer the differentiation protocols from coated Petri dish (2D) to internally coated alginate capsules (3D). Remarkably, we obtained this differentiation with a very high density of cells and a final viability of >97%, probably due either to a very good survival rate or phagocytosis of cell debris as observed in vivo.…”

In vitro modeling of hyperpigmentation associated to neurofibromatosis type 1 using melanocytes derived from human embryonic stem cells

“…of examples illustrate how such cells, retrieved from genetically selected donors carrying the causal mutation of a monogenic disorder, may reproduce disease-associated phenotypes (22)(23)(24)(25)(26). Thus, we used two human embryonic stem cell (hESC) lines derived from embryos characterized as mutant gene carriers for NF1 during a preimplantation diagnosis procedure, to explore mechanisms associated with hyperpigmentation in melanocytes and potential treatments for the pathological phenotype.…”

Protein kinase inhibitor β enhances the constitutive activity of G-protein-coupled zinc receptor GPR39

“…In addition, the enhanced growth and mobility of prostate carcinoma cells transfected with PKIB [15] may well be explained by enhanced RhoA-mediated signalling that regulates the actin and adhesion dynamics that control cell migration also in prostate carcinoma [27]. PKIB was also recently found to be down-regulated in human embryonic stem cell lines carrying the mutant huntingtin, which causes Huntington's disease and leads to striatal neurodegeneration [28].…”