Marmoset induced pluripotent stem cells: Robust neural differentiation following pretreatment with dimethyl sulfoxide

Autologous cord blood vs individualized supplements in autistic spectrum disorder: CORDUS study results

BACKGROUND

Cellular therapies have started an important new therapeutic direction in autistic spectrum disorder (ASD), and the ample diversity of ASD pathophysiology and the different types of cell therapies prompt an equally ample effort to employ clinical studies for studying the ASD causes and cell therapies. Stem cells have yielded so far mixed results in clinical trials, and at patient level the results varied from impressive to no improvement. In this context we have administered autologous cord blood (ACB) and a non-placebo, material intervention represented by an individualized combination of supplements (ICS) to ASD children.

AIM

To compare the efficacy of ACB vs ICS and find markers correlated with the child's progress in order to better predict ACB efficacy.

METHODS

CORDUS clinical study is a crossover study in which both oral ICS and intravenous ACB were sequentially administered to 56 children; ACB was infused as an inpatient procedure. Treatment efficacy was evaluated pre-treatment and post-treatment at 6 months by an independent psychotherapist with Autism Treatment Evaluation Checklist, Quantitative Checklist for Autism in Toddlers and a 16-item comparative table score, after interviewing the children’s parents and therapists. Before and after each intervention participants had a set of blood tests including inflammatory, metabolic and oxidative markers, and the neuronal specific enolase.

RESULTS

No serious adverse reactions were noted during and after cord blood or supplement administration. ACB improved evaluation scores in 78% of children with age 3–7-years (n = 28), but was much less effective in kids older than 8 years or with body weight of more than 35 kg (n = 28; only 11% of children improved scores). ICS yielded better results than ACB in 5 cases out of 28, while in 23 kids ACB brought more improvement than ICS (P < 0.05); high initial levels of inflammation and ferritin were associated with no improvement. Ample individual differences were noted in children's progress, and statistically significant improvements were seen after ACB on areas such as verbalization and social interaction, but not on irritability or aggressive behavior.

CONCLUSION

ACB has superior efficacy to ICS in ASD; high inflammation, ferritin, age and body weight predict less improvement; more clinical studies are needed for studying ACB efficacy in ASD.

Common Marmoset Cell Lines and Their Applications in Biomedical Research

Common marmosets (Callithrix jacchus; CMs) are small New World primates widely used in biomedical research. Early stages of such research often include in vitro experiments which require standardized and well-characterized CM cell cultures derived from different tissues. Despite the long history of laboratory work with CMs and high translational potential of such studies, the number of available standardized, well-defined, stable, and validated CM cell lines is still small. While primary cells and immortalized cell lines are mostly used for the studies of infectious diseases, biochemical research, and targeted gene therapy, the main current applications of CM embryonic stem cells and induced pluripotent stem cells are regenerative medicine, stem cell research, generation of transgenic CMs, transplantology, cell therapy, reproductive physiology, oncology, and neurodegenerative diseases. In this review we summarize the data on the main advantages, drawbacks and research applications of CM cell lines published to date including primary cells, immortalized cell lines, lymphoblastoid cell lines, embryonic stem cells, and induced pluripotent stem cells.

Non-human primate pluripotent stem cells for the preclinical testing of regenerative therapies

Non-human primates play a key role in the preclinical validation of pluripotent stem cell-based cell replacement therapies. Pluripotent stem cells used as advanced therapy medical products boost the possibility to regenerate tissues and organs affected by degenerative diseases. Therefore, the methods to derive human induced pluripotent stem cell and embryonic stem cell lines following clinical standards have quickly developed in the last 15 years. For the preclinical validation of cell replacement therapies in non-human primates, it is necessary to generate non-human primate pluripotent stem cell with a homologous quality to their human counterparts. However, pluripotent stem cell technologies have developed at a slower pace in non-human primates in comparison with human cell systems. In recent years, however, relevant progress has also been made with non-human primate pluripotent stem cells. This review provides a systematic overview of the progress and remaining challenges for the generation of non-human primate induced pluripotent stem cells/embryonic stem cells for the preclinical testing and validation of cell replacement therapies. We focus on the critical domains of (1) reprogramming and embryonic stem cell line derivation, (2) cell line maintenance and characterization and, (3) application of non-human primate pluripotent stem cells in the context of selected preclinical studies to treat cardiovascular and neurodegenerative disorders performed in non-human primates.

Generation of Pluripotent Stem Cells Using Somatic Cell Nuclear Transfer and Induced Pluripotent Somatic Cells from African Green Monkeys

Patient-specific stem cells derived from somatic cell nuclear transfer (SCNT) embryos or from induced pluripotent stem cells (iPSCs) could be used to treat various diseases with minimal immune rejection. Many studies using these cells have been conducted in rats and mice; however, there exist numerous dissimilarities between the rodents and humans limiting the clinical predictive power and experimental utility of rodent experiments alone. Nonhuman primates (NHPs) share greater homology to human than rodents in all respects, including genomics, physiology, biochemistry, and the immune system. Thus, experimental data obtained from monkey studies would be more predictive for designing an effective cell replacement therapy in humans. Unfortunately, there are few iPSC lines and even fewer SCNT lines that have been derived in NHPs, hampering broader studies in regenerative medicine. One promising potential therapy would be the replacement of dopamine neurons that are lost in Parkinson's disease. After dopamine depletion by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), the African green monkey (Chlorocebus sabaeus) shows the most complete model of Parkinsonism compared with other species and brain pathology and behavioral changes are almost identical to those in humans after accidental exposure to MPTP. Therefore, we have developed a SCNT procedure to generate multiple pluripotent stem cell lines in this species for studies of possible treatment of Parkinsonism and for comparing with cells derived from iPSCs. Using 24 female monkeys as egg donors and 7 somatic cell donor monkeys, we have derived 11 SCNT embryonic stem cell lines that expressed typical stemness genes and formed all three germ layer derivatives. We also derived two iPSC lines using an episome-mediated reprogramming factor delivery system. This report describes the process for deriving these cell lines and proving their pluripotency for differentiation into various potentially therapeutic cells.

Differential gene expression by lithium chloride induction of adipose-derived stem cells into neural phenotype cells

OBJECTIVES

Adipose-derived stem cells (ADSCs), with suitable and easy access, are multipotential cells that have the ability for differentiation into other mesodermal and transdifferentiate into neural phenotype cells. In this study, Lithium chloride (LiCl) was used for in vitro transdifferentiation of rat ADSCs into neuron-like cells (NLCs).

MATERIALS AND METHODS

ADSCs were isolated from the rats' perinephric region using Dulbecco΄s Modified Eagle΄s Medium (DMEM) with Fetal Bovine Serum (FBS), cultured for 3 passages, characterized by flowcytometry and differentiation into adipogenic and osteogenic phenotypes. The ADSCs were exposed to 0.1, 0.5, 1, 1.5, 2, 5, and 10 millimolar (mM) LiCl without serum for 24 hr. The optimum dose of LiCl was selected according the maximum viability of cells. The expression of neurofilament light chain (NfL), neurofilament high chain (NfH), and nestin was evaluated by immunocytochemistry. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to evaluate the amount of synaptophysin, neurogenin-1, neuroD1, NfL, NfH, and nestin genes' expression in ADSCs and NLCs.

RESULTS

The optimum dose of LiCl was 1 mM in 24 hr. The transdifferentiated ADSCs showed cytoplasmic extension with synapse-like formation. Synaptophysin, neurogenin-1, neuroD1, NfL, NfH, and nestin genes were significantly expressed more in NLCs than in ADSCs.

CONCLUSION

LiCl can induce ADSCs into neural phenotype cells with higher expression of neural and neuronal genes.

Dimethyl Sulfoxide Leads to Decreased Osteogenic Differentiation of Stem Cells Derived from Gingiva via Runx2 and Collagen I Expression

OBJECTIVES

Dimethyl sulfoxide (DMSO) plays various functions, including cellular functions such as cellular growth. The aim of this study was to evaluate the effects of DMSO on the proliferation and osteogenic differentiation of human gingiva-derived stem cells.

MATERIALS AND METHODS

Stem cells derived from gingiva were cultured in the presence of DMSO at concentrations ranging from 0.01 to 10%.

STATISTICAL ANALYSIS

We performed a one-way analysis of variance (ANOVA) with post hoc test to determine the differences between the groups using a commercially available program and the level of significance was 0.05.

RESULTS

The cells in the control group showed normal fibroblast morphology. The cells treated with 0.01%, 0.01%, 0.1%, and 1% DMSO were morphologically similar to those from the control group on each day. Statistically significant decreases in cell counting kit-8 (CCK-8) values were seen in the 3% and 10% DMSO groups (p < 0.05). A statistically significant decrease in alkaline phosphatase activity was seen in the 3% DMSO group. (p < 0.05). The application of DMSO produced a decrease in alizarin red S staining. The expression of Runx2 and collagen I by immunofluorescence decreased as the dose of lovastatin increased.

CONCLUSION

The effects of DMSO on the viability of osteogenic differentiation among stem cells derived from human gingiva were evaluated. Applying DMSO produced decreased cell viability and decreased osteogenic differentiation in this experimental setting. This should be considered when designing and interpreting the data, and a DMSO-free method may be considered for bone regeneration applications.

A transient DMSO treatment increases the differentiation potential of human pluripotent stem cells through the Rb family

The propensity for differentiation varies substantially across human pluripotent stem cell (hPSC) lines, greatly restricting the use of hPSCs for cell replacement therapy or disease modeling. Here, we investigate the underlying mechanisms and demonstrate that activation of the retinoblastoma (Rb) pathway in a transient manner is important for differentiation. In prior work, we demonstrated that pre-treating hPSCs with dimethylsulfoxide (DMSO) before directed differentiation enhanced differentiation potential across all three germ layers. Here, we show that exposure to DMSO improves the efficiency of hPSC differentiation through Rb and by repressing downstream E2F-target genes. While transient inactivation of the Rb family members (including Rb, p107, and p130) suppresses DMSO’s capacity to enhance differentiation across all germ layers, transient expression of a constitutively active (non-phosphorylatable) form of Rb increases the differentiation efficiency similar to DMSO. Inhibition of downstream targets of Rb, such as E2F signaling, also promotes differentiation of hPSCs. More generally, we demonstrate that the duration of Rb activation plays an important role in regulating differentiation capacity.

Standards for Deriving Nonhuman Primate-Induced Pluripotent Stem Cells, Neural Stem Cells and Dopaminergic Lineage

Humans and nonhuman primates (NHP) are similar in behavior and in physiology, specifically the structure, function, and complexity of the immune system. Thus, NHP models are desirable for pathophysiology and pharmacology/toxicology studies. Furthermore, NHP-derived induced pluripotent stem cells (iPSCs) may enable transformative developmental, translational, or evolutionary studies in a field of inquiry currently hampered by the limited availability of research specimens. NHP-iPSCs may address specific questions that can be studied back and forth between in vitro cellular assays and in vivo experimentations, an investigational process that in most cases cannot be performed on humans because of safety and ethical issues. The use of NHP model systems and cell specific in vitro models is evolving with iPSC-based three-dimensional (3D) cell culture systems and organoids, which may offer reliable in vitro models and reduce the number of animals used in experimental research. IPSCs have the potential to give rise to defined cell types of any organ of the body. However, standards for deriving defined and validated NHP iPSCs are missing. Standards for deriving high-quality iPSC cell lines promote rigorous and replicable scientific research and likewise, validated cell lines reduce variability and discrepancies in results between laboratories. We have derived and validated NHP iPSC lines by confirming their pluripotency and propensity to differentiate into all three germ layers (ectoderm, mesoderm, and endoderm) according to standards and measurable limits for a set of marker genes. The iPSC lines were characterized for their potential to generate neural stem cells and to differentiate into dopaminergic neurons. These iPSC lines are available to the scientific community. NHP-iPSCs fulfill a unique niche in comparative genomics to understand gene regulatory principles underlying emergence of human traits, in infectious disease pathogenesis, in vaccine development, and in immunological barriers in regenerative medicine.

Overcoming barriers to reprogramming and differentiation in nonhuman primate induced pluripotent stem cells

Induced pluripotent stem cells (iPS cells) generated by cellular reprogramming from nonhuman primates (NHPs) are of great significance for regenerative medicine and for comparative biology. Autologously derived stem cells would theoretically avoid any risk of rejection due to host–donor mismatch and may bypass the need for immune suppression post-transplant. In order for these possibilities to be realized, reprogramming methodologies that were initially developed mainly for human cells must be translated to NHPs. NHP studies have typically used pluripotent cells generated from young animals and thus risk overlooking complications that may arise from generating iPS cells from donors of other ages. When reprogramming is extended to a wide range of NHP species, available donors may be middle- or old-aged. Here we have pursued these questions by generating iPS cells from donors across the life span of the common marmoset (Callithrix jacchus) and then subjecting them to a directed neural differentiation protocol. The differentiation potential of different clonal cell lines was assessed using the quantitative polymerase chain reaction. The results show that cells derived from older donors often showed less neural marker induction. These deficits were rescued by a 24 h pretreatment of the cells with 0.5 % dimethyl sulfoxide. Another NHP that plays a key role in biological research is the chimpanzee (Pan troglodytes). iPS cells generated from the chimpanzee can be of great interest in comparative in vitro studies. We investigated if similar deficits in differentiation potential might arise in chimpanzee iPS cells reprogrammed using various technologies. The results show that, while some deficits were observed in iPS cell clones generated using three different technologies, there was no clear association with the vector used. These deficits in differentiation were also prevented by a 24 h pretreatment with 0.5 % dimethyl sulfoxide.

Induced Pluripotent Stem Cell-Derived Dopaminergic Neurons from Adult Common Marmoset Fibroblasts

The common marmoset monkey (Callithrix jacchus; Cj) is an advantageous nonhuman primate species for modeling age-related disorders, including Parkinson's disease, due to their shorter life span compared to macaques. Cj-derived induced pluripotent stem cells (Cj-iPSCs) from somatic cells are needed for in vitro disease modeling and testing regenerative medicine approaches. Here we report the development of a novel Cj-iPSC line derived from adult marmoset fibroblasts. The Cj-iPSCs showed potent pluripotency properties, including the development of mesodermal lineages in tumors after injection to immunocompromised mice, as well as ectoderm and endoderm lineages after in vitro differentiation regimens, demonstrating differentiated derivatives of all three embryonic layers. In addition, expression of key pluripotency genes (ZFP42, PODXL, DNMT3B, C-MYC, LIN28, KLF4, NANOG, SOX2, and OCT4) was observed. We then tested the neural differentiation capacity and gene expression profiles of Cj-iPSCs and a marmoset embryonic stem cell line (Cj-ESC) after dual-SMAD inhibition. Exposure to CHIR99021 and sonic hedgehog (SHH) for 12 and 16 days, respectively, patterned the cells toward a ventralized midbrain dopaminergic phenotype, confirmed by expression of FOXA2, OTX2, EN-1, and tyrosine hydroxylase. These results demonstrate that common marmoset stem cells will be able to serve as a platform for investigating regenerative medicine approaches targeting the dopaminergic system.

Differentiation and characterization of rhesus monkey atrial and ventricular cardiomyocytes from induced pluripotent stem cells

The combination of non-human primate animals and their induced pluripotent stem cell derived cardiomyocytes (iPSC-CMs) provides not only transplantation models for cell-based therapy of heart diseases, but also opportunities for heart-related drug research on both cellular and animal levels. However, the subtypes and electrophysiology properties of non-human primate iPSC-CMs hadn't been detailed characterized. In this study, we generated rhesus monkey induced pluripotent stem cells (riPSCs), and efficiently differentiated them into ventricular or atrial cardiomyocytes by modulating retinoic acid (RA) pathways. Our results revealed that the electrophysiological characteristics and response to canonical drugs of riPSC-CMs were similar with those of human pluripotent stem cell derived CMs. Therefore, rhesus monkeys and their iPSC-CMs provide a powerful and practicable system for heart related biomedical research.