Induced Pluripotent Stem Cell-Derived Chimeric Antigen Receptor T Cells: The Intersection of Stem Cells and Immunotherapy.

Chimeric antigen receptor (CAR) T cell therapy is a promising cell-based immunotherapy applicable to various cancers. High cost of production, immune rejection, heterogeneity of cell product, limited cell source, limited expandability, and relatively long production time have created the need to achieve a universal allogeneic CAR-T cell product for "off-the-shelf" application. Since the innovation of induced pluripotent stem cells (iPSCs) by Yamanaka et al., extensive efforts have been made to prepare an unlimited cell source for regenerative medicine, that is, immunotherapy. In the autologous grafting approach, iPSCs prepare the desired cell source for generating autologous CAR-T cells through more accessible and available sources. In addition, generating iPSC-derived CAR-T cells is a promising approach to achieving a suitable source for producing an allogeneic CAR-T cell product. In brief, the first step is reprogramming somatic cells (accessible from peripheral blood, skin, etc.) to iPSCs. In the next step, CAR expression and T cell lineage differentiation should be applied in different arrangements. In addition, in an allogeneic manner, human leukocyte antigen/T cell receptor (TCR) deficiency should be applied in iPSC colonies. The allogeneic iPSC-derived CAR-T cell experiments showed that simultaneous performance of HLA/TCR deficiency, CAR expression, and T cell lineage differentiation could bring the production to the highest efficacy in generating allogeneic iPSC-derived CAR-T cells.

Clinical parameters in different stages, zones, and remission/progression statuses of retinopathy of prematurity.

Background: Retinopathy of prematurity (ROP) is a vasoproliferative retinal disease in premature infants that causes lifetime visual impairment and blindness in the early ages. In this study, we investigated the differences in the values of clinical laboratory parameters between different ROP and its remission/progression statuses regarding stages and zones. Methods: This historical cohort study includes 828 infants divided into two groups after the first examination containing ROP infants and controls. The biochemical and hematological parameters of the two groups have been collected from the patient's history. Results: In infants with ROP, the hematopoiesis-related parameters, including the mean level of hemoglobin, total bilirubin, potassium, calcium were significantly less than controls (P=0.039, P=0.001, P=0.001, and P=0.046, respectively). The percentages of reticulocyte and the levels of BUN in ROP patients were significantly higher than in normal infants (P=0.015 and p <0.001, respectively). Moreover, the levels of hemoglobin and BUN were significantly different in the different zones of ROP (P=0.017 and P=0.001, respectively). Also, higher hemoglobin levels, total bilirubin, and CRP were observed in the reduced stages of ROP (P=0.041, P=0.045, and P=0.039, respectively). Conclusion: Laboratory parameters are different in different stages, zones and remission/ progression ROP infants.

CRISPR-Based Genome Editing as a New Therapeutic Tool in Retinal Diseases.

Retinal diseases are the primary reasons for severe visual defects and irreversible blindness. Retinal diseases are also inherited and acquired. Both of them are caused by mutations in genes or disruptions in specific gene expression, which can be treated by gene-editing therapy. Clustered regularly interspaced short palindromic repeats (CRISPR-Cas9) system is a frontier of gene-editing tools with great potential for therapeutic applications in the ophthalmology field to modify abnormal genes and treat the genome or epigenome-related retinal diseases. The CRISPR system is able to edit and trim the gene include deletion, insertion, inhibition, activation, replacing, remodeling, epigenetic alteration, and modify the gene expression. CRISPR-based genome editing techniques have indicated the enormous potential to treat retinal diseases that previous treatment was not available for them. Also, recent CRISPR genome surgery experiments have shown the improvement of patient's vision who suffered from severe visual loss. In this article, we review the applications of the CRISPR-Cas9 system in human or animal models for treating retinal diseases such as retinitis pigmentosa (RP), Leber congenital amaurosis (LCA), age-related macular degeneration (AMD), proliferative diabetic retinopathy (PDR), and proliferative vitreoretinopathy (PVR), then we survey limitations of CRISPR system for clinical therapy.

Induced pluripotent stem cell technology: trends in molecular biology, from genetics to epigenetics.

Induced pluripotent stem cell (iPSC) technology, based on autologous cells' reprogramming to the embryonic state, is a new approach in regenerative medicine. Current advances in iPSC technology have opened up new avenues for multiple applications, from basic research to clinical therapy. Thus, conducting iPSC trials have attracted increasing attention and requires an extensive understanding of the molecular basis of iPSCs. Since iPSC reprogramming is based on the methods inducing the expression of specific genes involved in pluripotency states, it can be concluded that iPSC reprogramming is strongly influenced by epigenetics. In this study, we reviewed the molecular basis of reprogramming, including the reprogramming factors (OCT4, SOX2, KLF4, c-MYC, NANOG, ESRRB, LIN28 as well as their regulatory networks), applied vectors (retroviral vectors, adenoviral vectors, Sendaiviral vectors, episomal plasmids, piggyBac, simple vectors, etc.) and epigenetic modifications (miRNAs, histones and DNA methylation states) to provide a comprehensive guide for reprogramming studies.

A Review of DNA and Histone Methylation Alterations in the New Era of Diagnosis and Treatment of Retinal Diseases.

Epigenetics has an important role in gene regulation and other cellular processes. DNA methylation, as one of the main mechanisms of epigenetics, is a type of post-replication modifications. Aberrant DNA methylation can alter gene expression patterns; so, it plays a considerable role in the pathogenesis of many diseases. DNA methylated alterations in the promoter of specific genes can be used for the diagnosis and proprietary targets acting as a "biomarker". Early diagnosis and prevention may be possible due to these biomarkers. According to recent studies, DNA methylation abnormalities have an important role in the retinogenesis and pathogenesis of retinal diseases. Retinal diseases are the main cause of blindness and severe vision loss in the world, which will continue to increase. Also, they inflict an enormous burden on society and health care systems. Therefore, it is important to focus on the better recognition and prevention of retinal diseases and finding new targets for the treatment. DNA methylation is lionized as attractive therapeutic targets due to its reversibility. Epigenetic therapy has a high potency in the treatment of retinal diseases. Here, we reviewed the DNA and histone methylation alterations in common retinal diseases, focusing on agerelated macular degeneration (AMD), diabetic retinopathy, retinal detachment (RD), retinitis pigmentosa, retinal aging, and retinoblastoma. Then we surveyed some new approaches to epigenetic therapy in retinal disorders.

CRISPR-mediated modification of DNA methylation pattern in the new era of cancer therapy.

In the last 2 decades, a wide variety of studies have been conducted on epigenetics and its role in various cancers. A major mechanism of epigenetic regulation is DNA methylation, including aberrant DNA methylation variations such as hypermethylation and hypomethylation in the promoters of critical genes, which are commonly detected in tumors and mark the early stages of cancer development. Therefore, epigenetic therapy has been of special importance in the last decade for cancer treatment. In epigenetic therapy, all efforts are made to modulate gene expression to the normal status. Importantly, recent studies have shown that epigenetic therapy is focusing on the new gene editing technology, CRISPR-Cas9. This tool was found to be able to effectively modulate gene expression and alter almost any sequence in the genome of cells, resulting in events such as a change in acetylation, methylation, or histone modifications. Of note, the CRISPR-Cas9 system can be used for the treatment of cancers caused by epigenetic alterations. The CRISPR-Cas9 system has greater advantages than other available methods, including potent activity, easy design and high velocity as well as the ability to target any DNA or RNA site. In this review, we described epigenetic modulators, which can be used in the CRISPR-Cas9 system, as well as their functions in gene expression alterations that lead to cancer initiation and progression. In addition, we surveyed various species of CRISPR-dead Cas9 (dCas9) systems, a mutant version of Cas9 with no endonuclease activity. Such systems are applicable in epigenetic therapy for gene expression modulation through chemical group editing on nucleosomes and chromatin remodeling, which finally return the cell to the normal status and prevent cancer progression.