Copy number variant hotspots in Han Taiwanese population induced pluripotent stem cell lines - lessons from establishing the Taiwan human disease iPSC Consortium Bank.

BACKGROUND: The Taiwan Human Disease iPSC Service Consortium was established to accelerate Taiwan's growing stem cell research initiatives and provide a platform for researchers interested in utilizing induced pluripotent stem cell (iPSC) technology. The consortium has generated and characterized 83 iPSC lines: 11 normal and 72 disease iPSC lines covering 21 different diseases, several of which are of high incidence in Taiwan. Whether there are any reprogramming-induced recurrent copy number variant (CNV) hotspots in iPSCs is still largely unknown. METHODS: We performed genome-wide copy number variant screening of 83 Han Taiwanese iPSC lines and compared them with 1093 control subjects using an Affymetrix genome-wide human SNP array. RESULTS: In the iPSCs, we identified ten specific CNV loci and seven "polymorphic" CNV regions that are associated with the reprogramming process. Additionally, we established several differentiation protocols for our iPSC lines. We demonstrated that our iPSC-derived cardiomyocytes respond to pharmacological agents and were successfully engrafted into the mouse myocardium demonstrating their potential application in cell therapy. CONCLUSIONS: The CNV hotspots induced by cell reprogramming have successfully been identified in the current study. This finding may be used as a reference index for evaluating iPSC quality for future clinical applications. Our aim was to establish a national iPSC resource center generating iPSCs, made available to researchers, to benefit the stem cell community in Taiwan and throughout the world.

IL-1ß promotes malignant transformation and tumor aggressiveness in oral cancer.

Chronic inflammation, coupled with alcohol, betel quid, and cigarette consumption, is associated with oral squamous cell carcinoma (OSCC). Interleukin-1 beta (IL-1ß) is a critical mediator of chronic inflammation and implicated in many cancers. In this study, we showed that increased pro-IL-1ß expression was associated with the severity of oral malignant transformation in a mouse OSCC model induced by 4-Nitroquinolin-1-oxide (4-NQO) and arecoline, two carcinogens related to tobacco and betel quid, respectively. Using microarray and quantitative PCR assay, we showed that pro-IL-1ß was upregulated in human OSCC tumors associated with tobacco and betel quid consumption. In a human OSCC cell line TW2.6, we demonstrated nicotine-derived nitrosamine ketone (NNK) and arecoline stimulated IL-1ß secretion in an inflammasome-dependent manner. IL-1ß treatment significantly increased the proliferation and dysregulated the Akt signaling pathways of dysplastic oral keratinocytes (DOKs). Using cytokine antibodies and inflammation cytometric bead arrays, we found that DOK and OSCC cells secreted high levels of IL-6, IL-8, and growth-regulated oncogene-α following IL-1ß stimulation. The conditioned medium of IL-1ß-treated OSCC cells exerted significant proangiogenic effects. Crucially, IL-1ß increased the invasiveness of OSCC cells through the epithelial-mesenchymal transition (EMT), characterized by downregulation of E-cadherin, upregulation of Snail, Slug, and Vimentin, and alterations in morphology. These findings provide novel insights into the mechanism underlying OSCC tumorigenesis. Our study suggested that IL-1ß can be induced by tobacco and betel quid-related carcinogens, and participates in the early and late stages of oral carcinogenesis by increasing the proliferation of dysplasia oral cells, stimulating oncogenic cytokines, and promoting aggressiveness of OSCC.

Gold nanoparticles regulate the blimp1/pax5 pathway and enhance antibody secretion in B-cells.

Nanoparticles are potential threats to human health and the environment; however, their medical applications as drug carriers targeting cancer cells bring hope to contemporary cancer therapy. As a model drug carrier, gold nanoparticles (GNPs) have been investigated extensively for in vivo toxicity. The effect of GNPs on the immune system, however, has rarely been examined. Antibody-secreting cells were treated with GNPs with diameters ranging from 2 to 50 nm. The GNPs enhanced IgG secretion in a size-dependent manner, with a peak of efficacy at 10 nm. The immune-stimulatory effect reached a maximum at 12 h after treatment but returned to control levels 24 h after treatment. This enhancing effect was validated ex vivo using B-cells isolated from mouse spleen. Evidence from RT-PCR and western blot experiments indicates that GNP-treatment upregulated B-lymphocyte-induced maturation protein 1 (blimp1) and downregulated paired box 5 (pax5). Immunostaining for blimp1 and pax5 in B-cells confirmed that the GNPs stimulated IgG secretion through the blimp1/pax5 pathway. The immunization of mice using peptide-conjugated GNPs indicated that the GNPs were capable of enhancing humoral immunity in a size-dependent manner. This effect was consistent with the bio-distribution of the GNPs in mouse spleen. In conclusion, in vitro, ex vivo, and in vivo evidence supports our hypothesis that GNPs enhance humoral immunity in mouse. The effect on the immune system should be taken into account if nanoparticles are used as carriers for drug delivery. In addition to their toxicity, the immune-stimulatory activity of nanoparticles could play an important role in human health and could have an environmental impact.

Generation of IBMS-iPSC-021, -022, -023 human induced pluripotent stem cells (IBMSi016-A, IBMSi017-A, and IBMSi018-A) derived from patients with the ALDH2 rs671 polymorphism.

ALDH2 gene is coded for the aldehyde dehydrogenase (ALDH), which is an enzyme involved in alcohol metabolism. Compared to normal aldehyde dehydrogenases, a homozygous point mutation on exon 12 from G to A significantly reduces its efficiency. In this study, we have reported the generation of IBMS-iPSC-021-04, IBMS-iPSC-022-01, and IBMS-iPSC-023-03 as induced pluripotent stem cell (iPSC) lines carrying the homozygous form of ALDH2 with the rs671 genetic polymorphism (E487K mutation). These cell lines were characterized in terms of pluripotency and differentiation potential. They serve as useful platforms to study alcohol metabolism and other chronic diseases associated with alcohol consumption.

Generation of induced pluripotent stem cell line-NTUHi001-A from a premature ovarian failure patient with Turner's syndrome mosaicism.

Turner's syndrome (TS) is one of the main causes of premature ovarian failure (POF). However, the mechanisms underlying POF are difficult to study due to the lack of suitable disease models. Herein, we have generated a human induced pluripotent stem cell (hiPSC) line derived from the peripheral blood mononuclear cells of a female patient with Turner's syndrome mosaicism via integration-free Sendai-virus system. The hiPSCs were confirmed with a 45, X karyotype and the acquisition of pluripotency. It's likely that hiPSCs can serve as a feasible cellular model for further pathophysiological studies of POF cases, especially for those originating in TS.

Reprogramming of a human induced pluripotent stem cell (iPSC) line (IBMSi012-A) from an early-onset Parkinson's disease patient harboring a homozygous p.D331Y mutation in the PLA2G6 gene.

A recessive mutation in PLA2G6, which is known to cause a heterogeneous neurodegenerative clinical spectrum, has recently been shown to be responsible for autosomal-recessive familial forms of Parkinson's disease (PD). Here, we generated induced pluripotent stem cells (iPSCs) from the peripheral blood mononuclear cells of a female patient with a homozygous PLA2G6 c.991G > T (p.D331Y) mutation by using the Sendai-virus delivery system. The resulting iPSCs showed pluripotency confirmed by immunofluorescent staining for pluripotency markers and differentiated into the 3 germ layers in vivo. This cellular model will provide a good resource for further pathophysiological studies of PD.

Generation of 2 induced pluripotent stem cell lines derived from patients with Parkinson's disease carrying LRRK2 G2385R variant.

Leucine rich repeat kinase (LRRK2) is the most prevalent genetic cause for Parkinson's disease. LRRK2 p.G2385R is an Asian specific genetic risk factor for sporadic Parkinson's disease. We generated two induced pluripotent stem cells (iPSCs), IBMS-iPSC-018-09 and IBMS-iPSC-020-01, from the peripheral blood mononuclear cells of two patients carrying LRRK2 p.G2385R variant by using the Sendai-virus delivery system. These iPSCs had a normal karyotype and exhibited pluripotency, such as an embryonic stem cell-like morphology, expression of pluripotent markers, and capacity to differentiate into three germ layers. This cellular model will provide a platform for pathophysiological studies of neurodegeneration in Parkinson's disease.

Generation of induced pluripotent stem cells from a patient with X-linked juvenile retinoschisis.

X-linked juvenile retinoschisis (XLRS) is a hereditary retinal dystrophy manifested as splitting of anatomical layers of retina. In this report, we generated a patient-specific induced pluripotent stem cell (iPSC) line, TVGH-iPSC-013-05, from the peripheral blood mononuclear cells of a male patient with XLRS by using the Sendai-virus delivery system. We believe that XLRS patient-specific iPSCs provide a powerful in vitro model for evaluating the pathological phenotypes of the disease.

Generation of induced pluripotent stem cells from a patient with spinocerebellar ataxia type 3.

Spinocerebellar ataxia type 3 (SCA3) is a dominantly inherited neurodegenerative disease caused by a trinucleotide repeat (CAG) expansion in the coding region of ATXN3 gene resulting in production of ataxin-3 with an elongated polyglutamine tract. Here, we generated induced pluripotent stem cells (iPSCs) from the peripheral blood mononuclear cells of a male patient with SCA3 by using the Sendai-virus delivery system. The resulting iPSCs had a normal karyotype, retained the disease-causing ATXN3 mutation, expressed pluripotent markers and could differentiate into the three germ layers. Potentially, the iPSCs could be a useful tool for the investigation of disease mechanisms of SCA3.

Generation of an induced pluripotent stem cell line from a 39-year-old female patient with severe-to-profound non-syndromic sensorineural hearing loss and a A1555G mutation in the mitochondrial MTRNR1 gene.

Sensorineural hearing loss (SNHL) is a prevalent form of deafness commonly arising from damage to the cochlear sensory hair cells and degeneration of the spiral ganglion neurons. In this study, Sendai virus was used to generate an induced pluripotent stem cell (iPSC) line from a 39-year-old female patient diagnosed with severe-to-profound, non-syndromic SNHL. The patient also carries a A1555G mutation in the mitochondrial 12S ribosome RNA gene (MTRNR1). This iPSC line was verified to express pluripotent markers, possess normal karyotype, harbor the specific mutation and demonstrated the capacity to differentiate into three germ layers.

Early Administration of Glutamine Protects Cardiomyocytes from Post-Cardiac Arrest Acidosis.

Postcardiac arrest acidosis can decrease survival. Effective medications without adverse side effects are still not well characterized. We aimed to analyze whether early administration of glutamine could improve survival and protect cardiomyocytes from postcardiac arrest acidosis using animal and cell models. Forty Wistar rats with postcardiac arrest acidosis (blood pH < 7.2) were included. They were divided into study (500 mg/kg L-alanyl-L-glutamine, n = 20) and control (normal saline, n = 20) groups. Each of the rats received resuscitation. The outcomes were compared between the two groups. In addition, cardiomyocytes derived from human induced pluripotent stem cells were exposed to HBSS with different pH levels (7.3 or 6.5) or to culture medium (control). Apoptosis-related markers and beating function were analyzed. We found that the duration of survival was significantly longer in the study group (p < 0.05). In addition, in pH 6.5 or pH 7.3 HBSS buffer, the expression levels of cell stress (p53) and apoptosis (caspase-3, Bcl-xL) markers were significantly lower in cardiomyocytes treated with 50 mM L-glutamine than those without L-glutamine (RT-PCR). L-glutamine also increased the beating function of cardiomyocytes, especially at the lower pH level (6.5). More importantly, glutamine decreased cardiomyocyte apoptosis and increased these cells' beating function at a low pH level.

Interleukin-1 beta transactivates epidermal growth factor receptor via the CXCL1-CXCR2 axis in oral cancer.

Hyperactivation of the epidermal growth factor receptor (EGFR) pathways and chronic inflammation are common characteristics of oral squamous cell carcinoma (OSCC). Previously, we reported that OSCC cells secrete interleukin-1 beta (IL-1ß), which promotes the proliferation of the oral premalignant cell line, DOK, and stimulates DOK and OSCC cells to produce the chemokine CXCL1. CXCL1 functions through CXCR2, a G protein-coupled receptor that transactivates EGFR in ovarian and lung cancers. We hypothesized that IL-1ß transactivates EGFR through the CXCL1-CXCR2 axis in OSCC. In this study, we demonstrated that tyrosine phosphorylation of EGFR is crucial for the IL-1ß-mediated proliferation and subsequent bromodeoxyuridine (BrdU) incorporation of DOK cells because the EGFR inhibitors AG1478 and erlotinib inhibit these abilities in a dose-dependent manner. Addition of IL-1ß instantly enhanced CXCL1 expression and secretion (within 15 min) in the DOK and OSCC cell lines. Furthermore, tyrosine phosphorylation of EGFR was significantly enhanced in DOK (1 h) and OSCC (20 min) cell lines after IL-1ß treatment, and both cell lines were inhibited on the addition of an IL-1 receptor antagonist (IL-1Ra). CXCL1 treatment resulted in EGFR phosphorylation, whereas the knockdown of CXCL1 expression by lentivirus-mediated shRNA or the addition of the CXCR2 antagonist SB225002 dramatically reduced IL-1ß-mediated EGFR phosphorylation and proliferation of DOK cells. Neutralizing antibodies against IL-1ß or CXCL1 markedly inhibited the constitutive or IL-1ß-induced tyrosine phosphorylation of EGFR in OSCC cells. IL-1ß transactivates EGFR through the CXCL1-CXCR2 axis, revealing a novel molecular network in OSCC that is associated with autocrine IL-1ß and EGFR signaling.