Gene and cell therapy of human genetic diseases: Recent advances and future directions.

Disruptions in normal development and the emergence of health conditions often result from the malfunction of vital genes in the human body. Decades of scientific research have focused on techniques to modify or substitute defective genes with healthy alternatives, marking a new era in disease treatment, prevention and cure. Recent strides in science and technology have reshaped our understanding of disorders, medication development and treatment recommendations, with human gene and cell therapy at the forefront of this transformative shift. Its primary objective is the modification of genes or adjustment of cell behaviour for therapeutic purposes. In this review, we focus on the latest advances in gene and cell therapy for treating human genetic diseases, with a particular emphasis on FDA and EMA-approved therapies and the evolving landscape of genome editing. We examine the current state of innovative gene editing technologies, particularly the CRISPR-Cas systems. As we explore the progress, ethical considerations and prospects of these innovations, we gain insight into their potential to revolutionize the treatment of genetic diseases, along with a discussion of the challenges associated with their regulatory pathways. This review traces the origins and evolution of these therapies, from conceptual ideas to practical clinical applications, marking a significant milestone in the field of medical science.

Genome engineering and disease modeling via programmable nucleases for insulin gene therapy; promises of CRISPR/Cas9 technology.

Targeted genome editing is a continually evolving technology employing programmable nucleases to specifically change, insert, or remove a genomic sequence of interest. These advanced molecular tools include meganucleases, zinc finger nucleases, transcription activator-like effector nucleases and RNA-guided engineered nucleases (RGENs), which create double-strand breaks at specific target sites in the genome, and repair DNA either by homologous recombination in the presence of donor DNA or via the error-prone non-homologous end-joining mechanism. A recently discovered group of RGENs known as CRISPR/Cas9 gene-editing systems allowed precise genome manipulation revealing a causal association between disease genotype and phenotype, without the need for the reengineering of the specific enzyme when targeting different sequences. CRISPR/Cas9 has been successfully employed as an ex vivo gene-editing tool in embryonic stem cells and patient-derived stem cells to understand pancreatic beta-cell development and function. RNA-guided nucleases also open the way for the generation of novel animal models for diabetes and allow testing the efficiency of various therapeutic approaches in diabetes, as summarized and exemplified in this manuscript.

HIV-based lentivirus-mediated vasoactive intestinal peptide gene delivery protects against DIO animal model of Type 2 diabetes.

Type 2 diabetes mellitus (T2DM) is characterised by insulin resistance, glucose intolerance and beta cell loss leading to hyperglycemia. Vasoactive intestinal peptide (VIP) has been regarded as a novel therapeutic agent for the treatment of T2DM because of its insulinotropic and anti-inflammatory properties. Despite these beneficial properties, VIP is extremely sensitive to peptidases (DPP-4) requiring constant infusion or multiple injections to observe any therapeutic benefit. Thus, we constructed an HIV-based lentiviral vector encoding human VIP (LentiVIP) to test the therapeutic efficacy of VIP peptide in a diet-induced obesity (DIO) animal model of T2DM. VIP gene expression was shown by immunocytochemistry (ICC) and VIP peptide secretion was confirmed by ELISA both in HepG2 liver and MIN6 pancreatic beta cell lines. Functional properties of VIP were demonstrated by cAMP production assay and glucose-stimulated insulin secretion test (GSIS). Intraperitoneal (IP) delivery of LentiVIP vectors into mice significantly increased serum VIP concentrations compared to control mice. Most importantly, LentiVIP delivery in DIO animal model of T2DM resulted in improved insulin sensitivity, glucose tolerance and protection against STZ-induced diabetes in addition to reduction in serum triglyceride/cholesterol levels. Collectively, these data suggest LentiVIP delivery should be evaluated as an experimental therapeutic approach for the treatment of T2DM.