Proliferative and chondrogenic potential of mesenchymal stromal cells from pluripotent and bone marrow cells.

INTRODUCTION: Mesenchymal stromal cells (MSCs) can be derived from a wide range of fetal and adult sources including pluripotent stem cells (PSCs). The properties of PSC-derived MSCs need to be fully characterized, in order to evaluate the feasibility of their use in clinical applications. PSC-MSC proliferation and differentiation potential in comparison with bone marrow (BM)-MSCs is still under investigation. The objective of this study was to determine the proliferative and chondrogenic capabilities of both human induced pluripotent stem cell (hiPSC-) and embryonic stem cell (hESC-) derived MSCs, by comparing them with BM-MSCs. METHODS: MSCs were derived from two hiPSC lines (hiPSC-MSCs), the well characterized Hues9 hESC line (hESC-MSCs) and BM from two healthy donors (BM-MSCs). Proliferation potential was investigated using appropriate culture conditions, with serial passaging, until cells entered into senescence. Differentiation potential to cartilage was examined after in vitro chondrogenic culture conditions. RESULTS: BM-MSCs revealed a fold expansion of 1.18x105 and 2.3x105 while the two hiPSC-MSC lines and hESC-MSC showed 5.88x10¹°, 3.49x108 and 2.88x108, respectively. Under chondrogenic conditions, all MSC lines showed a degree of chondrogenesis. However, when we examined the formed chondrocyte micromasses by histological analysis of the cartilage morphology and immunohistochemistry for the chondrocyte specific markers Sox9 and Collagen II, we observed that PSC-derived MSC lines had formed pink rather than hyaline cartilage, in contrast to BM-MSCs. CONCLUSION: In conclusion, MSCs derived from both hESCs and hiPSCs had superior proliferative capacity compared to BM-MSCs, but they were inefficient in their ability to form hyaline cartilage.

Therapeutic Effects of Mesenchymal Stem Cells Derived From Bone Marrow, Umbilical Cord Blood, and Pluripotent Stem Cells in a Mouse Model of Chemically Induced Inflammatory Bowel Disease.

Acute inflammatory bowel disease (AIBD) is a wide clinical entity including severe gastrointestinal pathologies with common histopathological basis. Epidemiologically increasing diseases, such as necrotizing enterocolitis (NEC), gastrointestinal graft versus host disease (GVHD), and the primary acute phase of chronic inflammatory bowel disease (CIBD), exhibit a high necessity for new therapeutic strategies. Mesenchymal stem cell (MSC) cellular therapy represents a promising option for the treatment of these diseases. In our study, we comparatively assess the efficacy of human MSCs derived from bone marrow (BM), umbilical cord blood (UCB), human embryonic stem cells (ESCs), or human-induced pluripotent stem cells (iPSCs) in a mouse model of chemically induced acute enterocolitis. The laboratory animals were provided ad libitum potable dextrane sulfate sodium solution (DSS) in order to reproduce an AIBD model and then individually exposed intraperitoneally to MSCs derived from BM (BM-MSCs), UCB (UCB-MSCs), ESCs (ESC-MSCs), or iPSCs (iPSC-MSCs). The parameters used to evaluate the cellular treatment efficacy were the animal survival prolongation and the histopathological-macroscopic picture of bowel sections. Although all categories of mesenchymal stem cells led to statistically significant survival prolongation compared to the control group, significant clinical and histopathological improvement was observed only in mice receiving BM-MSCs and UCB-MSCs. Our results demonstrated that the in vivo anti-inflammatory effect of ESC-MSCs and iPSC-MSCs was inferior to that of UCB-MSCs and BM-MSCs. Further investigation will clarify the potential of ESCs and iPSC-derived MSCs in AIBD treatment.

Reprogramming of bone marrow derived mesenchymal stromal cells to human induced pluripotent stem cells from pediatric patients with hematological diseases using a commercial mRNA kit.

The potential use of patient-specific induced pluripotent stem cells (hiPSCs) in the study and treatment of hematological diseases requires the setup of efficient and safe protocols for hiPSC generation. We aimed to adopt a reprogramming method for large-scale production of integration-free patient-specific hiPSC-lines in our stem cell processing laboratory, which supports a pediatric hematopoietic stem cell transplant unit located at a tertiary care children's hospital. We describe our 5-year experience in generation of hiPSC-lines from human bone marrow-derived mesenchymal stromal cells (BM-MSCs) using synthetic mRNAs encoding reprogramming factors. We generated hiPSC-lines from pediatric patients with ß-Thalassemia, Sickle Cell Anemia, Blackfan-Diamond Anemia, Severe Aplastic Anemia, DOCK8 Immunodeficiency and 1 healthy control. After optimization of the reprogramming procedure, average reprogramming efficiency of BM-MSCs was 0.29% (range 0.25-0.4). The complete reprogramming process lasted 14-16 days. Three to five hiPSC-colonies per sample were selected, expanded to 5 culture passages and then frozen. The whole procedure took an average time of 1.8 months (range 1.6-2.2). The hiPSC-lines expressed embryonic stem cell markers and exhibited pluripotency. This mRNA reprogramming method can be applicable in a hematopoietic stem cell culture lab setting and would be useful for the clinical translation of patient-specific hiPSCs.

Generation of human ß-thalassemia induced pluripotent cell lines by reprogramming of bone marrow-derived mesenchymal stromal cells using modified mRNA.

Synthetic modified mRNA molecules encoding pluripotency transcription factors have been used successfully in reprogramming human fibroblasts to induced pluripotent stem cells (iPSCs). We have applied this method on bone marrow-derived mesenchymal stromal cells (BM-MSCs) obtained from a patient with ß-thalassemia (ß-thal) with the aim to generate trangene-free ß-thal-iPSCs. Transfection of 10(4) BM-MSCs by lipofection with mRNA encoding the reprogramming factors Oct4, Klf4, Sox2, cMyc, and Lin28 resulted in formation of five iPSC colonies, from which three were picked up and expanded in ß-thal-iPSC lines. After 10 serial passages in vitro, ß-thal-iPSCs maintain genetic stability as shown by array comparative genomic hybridization (aCGH) and are capable of forming embryoid bodies in vitro and teratomas in vivo. Their gene expression profile compared to human embryonic stem cells (ESCs) and BM-MSCs seems to be similar to that of ESCs, whereas it differs from the profile of the parental BM-MSCs. Differentiation cultures toward a hematopoietic lineage showed the generation of CD34(+) progenitors up to 10%, but with a decreased hematopoietic colony-forming capability. In conclusion, we report herein the generation of transgene-free ß-thal-iPSCs that could be widely used for disease modeling and gene therapy applications. Moreover, it was demonstrated that the mRNA-based reprogramming method, used mainly in fibroblasts, is also suitable for reprogramming of human BM-MSCs.

Successful management of cryopyrin-associated periodic syndrome with canakinumab in infancy.

Neonatal onset multisystem inflammatory disease (NOMID)/chronic infantile neurologic cutaneous and articular (CINCA) syndrome is a rare, early-onset autoinflammatory disorder and the most severe form of cryopyrin-associated periodic syndrome, which is associated with overproduction of interleukin (IL)-1ß. This is a case report of a 70-day-old boy, who was diagnosed with NOMID/CINCA syndrome and who has been treated with anti-IL-1ß monoclonal antibody (canakinumab) since then, despite his early infancy. The patient presented with fever, aseptic meningitis, and rash. The clinical manifestations combined with the elevated acute-phase reactants strengthened the suspicion of the diagnosis of NOMID/CINCA syndrome. Specific immunologic workup revealed high levels of serum amyloid A and IL-6. The clinical diagnosis was confirmed by the detection of a de novo mutation of the CIAS1/NLR3 gene (p.Thr348Met), and canakinumab was started at a dose of 4 mg/kg, higher than the recommended dose for older age. White blood cell, serum amyloid A, C-reactive protein, and IL-6 levels quickly decreased and became normal within a month, and the clinical condition of the patient improved significantly. The infant remains without recurrence of disease or further complications and with satisfactory mental development with anti-IL-1ß monoclonal antibody treatment for >2 years. This report indicates the importance of early diagnosis of NOMID/CINCA syndrome and medication with IL-1 blockers as soon as possible for the improvement of the prognosis of cryopyrin-associated periodic syndrome and of a better patient outcome.

Primary immunodeficiency diseases: a 30-year patient registry from the referral center for primary immunodeficiencies in Greece.

Primary Immunodeficiencies (PID) represent a group of heterogeneous immune diseases with important biological significance. We reviewed the records of children diagnosed with PID in the Referral Center for PID in our country in order to describe the epidemiological, clinical and laboratory characteristics of immunodeficient patients. During a 30-year period, 147 patients (101 males, 68.7 %), with a mean age of 6.5 years at the time of diagnosis, were diagnosed with PID. The most prevalent diagnoses of PID were: "Combined Immunodeficiency" in 46 (31.3 %) patients, "Well-defined immunodeficiency syndrome" in 35 (23.1 %) patients, "Predominantly antibody deficiency" in 30 (20.4 %) patients and "Congenital defect of phagocyte function or both" in 28 (19 %) patients. There was a higher prevalence of males with "Combined immunodeficiency" (p < 0.033) and "Predominantly antibody deficiency" (p < 0.02) compared to females. The median age of children at the onset of symptoms and at the time of diagnosis was 0.5y (IQR: 0.1-2.5) and 2y (IQR: 0.6-7.2), respectively. The median diagnostic delay was 0.9y (IQR: 0.2-4.8). This period was shorter for patients with "Combined immunodeficiency" [median 0.3y (IQR: 0.1-1)], and longer for those with "Predominantly antibody deficiency" [median 3.2y (IQR: 0.2-5.9) or "Disease of immune dysregulation" [median 3.2y (IQR: 0.1-6.6)]. Comparing the rates in our population with those of the European Registry (ESID), the rates of "Combined immunodeficiencies", "Well-defined syndromes" and "Congenital birth defects and/or function of phagocytes" were significantly higher in this study (p <0,001). PID registry analysis improves knowledge in the field of Immunology and enhances awareness, early detection, diagnosis, and management of this rare but significant group of diseases.

Mesenchymal derivatives of genetically unstable human embryonic stem cells are maintained unstable but undergo senescence in culture as do bone marrow-derived mesenchymal stem cells.

Recurrent chromosomal alterations have been repeatedly reported in cultured human embryonic stem cells (hESCs). The effects of these alterations on the capability of pluripotent cells to differentiate and on growth potential of their specific differentiated derivatives remain unclear. Here, we report that the hESC lines HUES-7 and -9 carrying multiple chromosomal alterations produce in vitro mesenchymal stem cells (MSCs) that show progressive growth arrest and enter senescence after 15 and 16 passages, respectively. There was no difference in their proliferative potential when compared with bone marrow-derived MSCs. Array comparative genomic hybridization analysis (aCGH) of hESCs and their mesenchymal derivatives revealed no significant differences in chromosomal alterations, suggesting that genetically altered hESCs are not selected out during differentiation. Our findings indicate that genetically unstable hESCs maintain their capacity to differentiate in vitro into MSCs, which exhibit an in vitro growth pattern of normal MSCs and not that of transformed cells.

Chronic granulomatous disease: a 25-year patient registry based on a multistep diagnostic procedure, from the referral center for primary immunodeficiencies in Greece.

Chronic Granulomatous Disease (CGD) is an uncommon primary immunodeficiency caused by the absence or dysfunction of one of NADPH oxidase subunits, with heterogeneous genetic aetiologies. The aim of this study was the CGD patient registry in Greece, the identification of the responsible genotype and the potential correlation with the patient's clinical phenotype. Medical charts of 24 CGD patients, investigated by NBT test or DHR for NADPH oxidase activity, Western blot analysis for NADPH oxidase component expression and DNA sequencing (pyro- and cycle sequencing) for mutation analysis, were reviewed. All patients, but one, were classified into the different types of CGD. Sixteen patients from 14 unrelated families had X-linked CGD (66.7 %), four had mutations in the NCF1 gene (19 %), and three, from two unrelated families, had mutations in NCF2 (9.5 %) [Corrected]. Fifteen mutations were detected in the CYBB gene, including nonsense (53.8 %), splice site (30.8 %) and missense mutations (7.7 %), and deletions (7.7 %). Two novel mutations were identified; one in CYBB and one in NCF1. Carrier detection for X-CGD revealed that the de novo mutation rate was about 7 %. Prenatal diagnosis identified one affected male in three male fetuses tested. In both the X-linked and the autosomal recessive (AR-CGD) group, the gastrointestinal and respiratory manifestations were more common, followed by lympadenopathy in X-CGD and skin infections in the AR-CGD group. The patients with a mutation in CYBB had a wider variability of clinical manifestations and earlier diagnosis (4.6 years) compared to the AR-CGD group (12.9 years). The incidence of CGD in Greece is estimated at 0.90 (95 % CI 0.89-0.91) per 100,000 live births for the last decade.

HLA class II high-resolution genotyping in Greek children with celiac disease and impact on disease susceptibility.

BACKGROUND: Celiac disease (CD) has been associated with HLA class II heterodimers. This study aimed at determining the HLA genotypic and allelic distribution in Greek children with CD as compared with the general population. METHODS: A total of 118 children with CD and 120 healthy individuals serving as controls were included in the study. RESULTS: Higher frequencies for HLA-DQB1*02:01 (40.25 vs. 9.58%, P < 0.001) and DQB1*02:02 (20.34 vs. 5.42%, P < 0.001) were observed in patients with CD, whereas HLA-DQB1*03:01 (16.53 vs. 30.42%, P < 0.001), DQB1*05:01 (0.85 vs. 10%, P < 0.001), and DQB1*05:02 (5.51 vs. 17.92%, P < 0.001) were significantly lower, as compared with the controls. DQA1*02:01 (patients with CD vs. controls: 20.76 vs. 6.67%, P < 0.001) and DQA1*05:01 (40.25 vs. 9.58%, P < 0.001) were significantly more frequent in patients. The frequencies of HLA-DQA1* 01:01, *01:02, *01:04, and *05:05 were significantly lower in patients (P < 0.001). The haplotype mainly associated with CD was DRB1*03-DQB1*02:01-DQA1*05:01; patients with CD vs. controls: 39.83 vs. 9.58%, P < 0.001. In total, 84.75% of patients carried DQ2 (vs. 21.67% in controls, P < 0.001), whereas 11.02% were DQ8 positive/DQ2 negative. CONCLUSION: This study confirms the existing data and provides additional evidence supporting a strong genetic predisposition for CD associated with the class II alleles DQB1*02 and DQA1*05 encoding the serological specificity DQ2.

Update on the mechanism of action and on clinical efficacy of extracorporeal photopheresis in the treatment of acute and chronic graft versus host disease in children.

Extracorporeal photopheresis (ECP) has been used for treatment of steroid-refractory graft versus host disease (GVHD) with encouraging results. Although its exact mechanism of action is not fully understood, photoapheresed cells seem to induce a selective immune response directed against alloreactive T cell populations without causing generalized immunosuppression. Current pediatric experience with ECP for GVHD is available in the form of a few retrospective small studies concerning children with steroid refractory GVHD. Reviewing these data we conclude that ECP is a safe procedure, well tolerated even in low-weight pediatric patients, which warrants further evaluation in well-designed, prospective, controlled studies.

Cytokine gene polymorphisms and graft-versus-host disease in children after matched sibling hematopoietic stem cell transplantation: a single-center experience.

Various polymorphisms in cytokine genes have recently been investigated as candidate risk factors in allogeneic hematopoetic stem cell transplantation (allo-HSCT). We retrospectively analyzed specific polymorphisms in genes for interleukin (IL)-10, IL-6, tumor-necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ) in a pediatric cohort of 57 histocompatibility leucocyte antigen (HLA)-identical sibling myeloablative transplants. Both recipient and donor genotypes were tested for association with graft-versus-host disease (GVHD) by statistical methods including Cox regression analysis. We found a significant association between the IL-10 promoter haplotype polymorphisms at positions -1082, -819 and -592 with the occurrence of severe (grades III-IV) acute GVHD (aGVHD). Recipients with the haplotype GCC had a statistically significant decreased risk of severe aGVHD (hazard risk (HR)=0.20, 95% confidence interval (CI): 0.06-0.67) in comparison with patients with other IL-10 haplotypes (P=0.008). Transplant-related mortality at 1 year was significantly lower in recipients with this haplotype (HR=0.17, 95% CI: 0.012-0.320) versus other IL-10 haplotypes (P=0.03), whereas overall survival was not influenced by IL-10 haplotype polymorphisms. In multivariate analysis, the presence of the IL-10 GCC haplotype was found as the only variable associated with a statistically significant decreased hazard of severe aGVHD development (P=0.02, HR=0.21, 95% CI: 0.05-0.78). These results suggest that pediatric patients possessing the IL-10 GCC haplotype may be protected from the occurrence of severe aGVHD in the setting of matched sibling HSCT.