Decellularized Placental Sponge Seeded with Human Mesenchymal Stem Cells Improves Deep Skin Wound Healing in the Animal Model.

Skin injuries lead to a large burden of morbidity. Although numerous clinical and scientific strategies have been investigated to repair injured skin, optimal regeneration therapy still poses a considerable obstacle. To address this challenge, decellularized extracellular matrix-based scaffolds recellularized with stem cells offer significant advancements in skin regeneration and wound healing. Herein, a decellularized human placental sponge (DPS) was fabricated using the decellularization and freeze-drying technique and then recellularized with human adipose-derived mesenchymal cells (MSCs). The biological and biomechanical properties and skin full-thickness wound healing capacity of the stem cells-DPS constructs were investigated in vitro and in vivo. The DPS exhibited a uniform 3D microstructure with an interconnected pore network, 89.21% porosity, a low degradation rate, and good mechanical properties. The DPS and MSCs-DPS constructs were implanted in skin full-thickness wound models in mice. An accelerated wound healing was observed in the wounds implanted with the MSCs-DPS construct when compared to DPS and control (wounds with no treatment) during 7 and 21 days postimplantation follow-up. In the MSCs-DPS group, the wound was completely re-epithelialized, the epidermis layer was properly organized, and the dermis and epidermis' bilayer structures were restored after 7 days. Our findings suggest that DPS is an excellent carrier for MSC culture and delivery to skin wounds and now promises to proceed with clinical evaluations.

Engineering of a decellularized bovine skin coated with antibiotics-loaded electrospun fibers with synergistic antibacterial activity for the treatment of infectious wounds.

An ideal antibacterial wound dressing with strong antibacterial behavior versus highly drug-resistant bacteria and great wound-healing capacity is still being developed. There is a clinical requirement to progress the current clinical cares that fail to fully restore the skin structure due to post-wound infections. Here, we aim to introduce a novel two-layer wound dressing using decellularized bovine skin (DBS) tissue and antibacterial nanofibers to design a bioactive scaffold with bio-mimicking the native extracellular matrix of both dermis and epidermis. For this purpose, polyvinyl alcohol (PVA)/chitosan (CS) solution was loaded with antibiotics (colistin and meropenem) and electrospun on the surface of the DBS scaffold to fabricate a two-layer antibacterial wound dressing (DBS-PVA/CS/Abs). In detail, the characterization of the fabricated scaffold was conducted using biomechanical, biological, and antibacterial assays. Based on the results, the fabricated scaffold revealed a homogenous three-dimensional microstructure with a connected pore network, a high porosity and swelling ratio, and favorable mechanical properties. In addition, according to the cell culture result, our fabricated two-layer scaffold surface had a good interaction with fibroblast cells and provided an excellent substrate for cell proliferation and attachment. The antibacterial assay revealed a strong antibacterial activity of DBS-PVA/CS/Abs against both standard strain and multidrug-resistant clinical isolates of Acinetobacter baumannii, Pseudomonas aeruginosa, and Escherichia coli. Our bilayer antibacterial wound dressing is strongly suggested as an admirable wound dressing for the management of infectious skin injuries and now promises to advance with preclinical and clinical research.

Patterns of DNMT1 Promoter Methylation in Patients with Acute Lymphoblastic Leukemia.

Background: Acute lymphoblastic leukemia (ALL) is a clonal malignant disorder characterized by an uncontrolled proliferation of immature T or B lymphocytes. Extensive studies have shown that the epigenetic changes, especially modified DNA methylation patterns in the regulatory regions through the DNA methyltransferase (DNMTs), play an important role in the development of genetic disorders and abnormal growth and maturation capacity of leukemic stem cells (LSCs).The aim of this study was to evaluate the changes in DNMT1 promoter methylation and its expression pattern in patients with ALL. Materials and Methods: In this experimental study, methylation specific PCR (MSP) was used to assess the methylation status of DNMT1 promoter regions in samples collected from ALL patients (n=45) and healthy control subjects. According to this method, un-methylated cytosine nucleotides are converted to uracil by sodium bisulfite and the proliferation of methylated and un-methylated regions are performed using specific primers for target sequences. Results: None of the patients with B and T-ALL showed methylated promoter regions of the DNMT1 gene, while the methylation pattern of both pre-B ALL patients and the control group showed a relative promoter methylation. Conclusion: Analysis of promoter methylation patterns in various subgroups of ALL has revealed the importance of DNMT1 in the regulation of gene expression. Likewise, extensive data have also highlighted the methylation-based mechanisms exerted by DNAM1 as one of the main participants regulating gene expression in B-ALL and T-ALL patients. Investigation of the overall DNA methylation pattern offers significant improvements in the prediction of disease prognosis and treatment response.

Optimizing peripheral blood stem cells transplantation outcome through amend relapse and graft failure: a review of current literature.

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) has been considered as a valuable approach in treatment of numerous malignant and none malignant hematologic disorders. However, relapse and poor graft function (PGF) after allo-SCT remain to be controversial issues which may affect the transplantation outcome. Relevant articles were searched in MEDLINE database (2000-2016) using keywords and phrases: donor lymphocyte infusions, allogeneic stem cells transplantation, relapsed hematologic malignancies, booster schedules, cell dose, laboratory monitoring protocols and technical aspects of apheresis. Relapse of disease and PGF could be reduced via noting some main points such as choosing the suitable time and patient for donor lymphocyte infusion (DLI) and also determination of patients who ought to candidate for second allogeneic HSCT or for the use of stem cell boost. DLI and stem cell booster are promising treatment strategies noted in this review. Finally, this paper discusses indications and technical aspects of DLI and stem cell booster in hematological malignancies and emphasizes their therapeutic or pre-emptive potentials.

A Review on Iron Chelators in Treatment of Iron Overload Syndromes.

Iron chelation therapy is used to reduce iron overload development due to its deposition in various organs such as liver and heart after regular transfusion. In this review, different iron chelators implicated in treatment of iron overload in various clinical conditions have been evaluated using more up-to-date studies focusing on these therapeutic agents. Deferoxamine, Deferiprone and Deferasirox are the most important specific US FDA-approved iron chelators. Each of these chelators has their own advantages and disadvantages, various target diseases, levels of deposited iron and clinical symptoms of the afflicted patients which may affect their selection as the best modality. Taken together, in many clinical disorders, choosing a standard chelator does not have an accurate index which requires further clarifications. The aim of this review is to introduce and compare the different iron chelators regarding their advantages and disadvantages, usage dose and specific applications.

Human Platelet Lysate as a Xeno Free Alternative of Fetal Bovine Serum for the In Vitro Expansion of Human Mesenchymal Stromal Cells.

BACKGROUND: Mesenchymal stromal cells (MSCs) are employed in various different clinical settings in order to modulate immune response. Human autologous and allogeneic supplements including platelet derivatives such as platelet lysate (PL), platelet-released factors (PRF) and serum are assessed in clinical studies to replace fetal bovine serum (FBS). The immunosuppressive activity and multi-potential characteristic of MSCs appear to be maintained when the cells are expanded in platelet derivatives. MATERIALS AND METHODS: Platelet-rich plasma was collected from umbrical cord blood (UCB). Platelet-derived growth factors obtained by freeze and thaw methods. CD62P expression was determined by flow cytometry. The concentration of PDGF-BB and PDGF-AB was detemined by ELISA. We tested the ability of a different concentration of PL-supplemented medium to support the ex vivo expansion of Wharton's jelly derived MSCs. We also investigated the biological/functional properties of expanded MSCs in presence of different concentration of PL. The conventional karyotyping was performed in order to study the chromosomal stability. The gene expression of Collagen I and II aggrecan and SOX-9 in the presence of different concentrations of PL was evaluated by Real-time PCR. RESULTS: We observed 5% and 10% PL, causing greater effects on proliferation of MSCs .These cells exhibited typical morphology, immunophenotype and differentiation capacity. The genetic stability of these derivative cells from Wharton's jelly was demonstrated by a normal karyotype. Furthermore, the results of Real-time PCR analysis showed that the expression of chondrocyte specific genes was higher in MSCs in the presence of 5% and 10% PL, compared with FBS supplement. CONCLUSIONS: We demonstrated that PL could be used as an alternative safe source of growth factors for expansion of MSCs and also maintained similar growing potential and phenotype without any effect on chromosomal stability.

Short view of leukemia diagnosis and treatment in iran.

BACKGROUND: Early diagnosis and treatment of leukemia patients remains a fundamental aim in clinical oncology, especially in developing country. Present study highlights the basic requirements of these patients in Iran. Better understanding of these issues may lead to improve the healthcare standards toward leukemia diagnosis and treatment. METHODS: This descriptive study included 101 specialists in hematology-oncology and pathology serving in oncology centers. The participants were then asked to fill out a standard questionnaire on the issues around diagnosis and treatment of blood malignancies. RESULTS: According to specialists, unfair distribution of facilities across the country, delayed diagnosis of disease, absence of psychological support for patients, and insufficient financial support were the main reasons of inappropriate diagnosis and treatment in leukemia patients. CONCLUSIONS: Our results show that making an amendment to health policies by preparing well-equipped medical centers in all provinces, improving the morale of patients through consultation during the process of treatment, and above all, subsiding leukemia patients' financial problems will promote the health standard regarding the leukemia diagnosis and treatment in Iran.

Efficient Differentiation of Human Induced Pluripotent Stem Cell (hiPSC) Derived Hepatocyte-Like Cells on hMSCs Feeder.

BACKGROUND: The use of stem cells is considered as an appropriate source in cell therapy and tissue engineering. Differentiation of human induced Pluripotent Stem Cells (hiPSCs) to Hepatocyte-like Cells (HLCs) on mouse embryonic fibroblasts (MEFs) feeders is confronted with several problems that hinder the clinical applications of these differentiated cells for the treatment of liver injuries. Safe appropriate cells for stem cell-based therapies could create new hopes for liver diseases. This work focused on the determination of a capacity/efficiency for the differentiation of the hiPSCs into Hepatocyte-like Cells on a novel human adult bone marrow mesenchymal stem cells (hMSCs) feeder. MATERIALS AND METHODS: Undifferentiated human iPSCs were cultured on mitotically inactivated human adult bone marrow mesenchymal stem cells. A three-step differentiation process has been performed in presence of activin A which added for 3 days to induce a definitive endoderm formation. In the second step, medium was exchanged for six days. Subsequently, cells were treated with oncostatin M plus dexamethasone for 9 days to generate hepatic cells. Endodermic and liver-specific genes were assessed via quantitative reverse transcription-polymerase chain reaction and RT-PCR, moreover, immunocytochemical staining for liver proteins including albumin and alpha-fetoprotein. In addition, functional tests for glycogen storage, oil red examination, urea production and alpha-fetoprotein synthesis, as well as, cells differentiated with a hepatocyte-like morphology was also performed. RESULTS: Our results show that inactivated human adult bone marrow mesenchymal stem cell feeders could support the efficient differentiation of hiPSCs into HLCs. This process induced differentiation of iPSCs into definitive endocrine cells that expressed sox17, foxa2 and expression of the specific genes profiles in hepatic-like cells. In addition, immunocytochemical analysis confirmed albumin and alpha-fetoprotein protein expression, as well as, the hiPSCs-derived Hepatocyte-like Cells on human feeder exhibited a typical morphology. CONCLUSIONS: we suggested a successful and efficient culture for differentiation and maturation of hepatocytes on an alternative human feeders; this is an important step to generate safe and functional hepatocytes that is vital for regenerative medicine and transplantation on the cell-based therapies.

Genetic Variations of Tumor Necrosis Factor -α-308 and Lymphtoxin-α+252 in Non-Hodgkin Lymphoma and Acute Lymphoblastic Leukemia Patients.

OBJECTIVE(S): Non- Hodgkin lymphoma (NHL) and acute lymphoblastic leukemia (ALL) are two main hematological malignances which have been driven from lymphoid tissue. Genetic polymorphisms in tumor necrosis factor-α (TNF-α) -308 and lymphotoxin-α (LT-α) +252 may affect their transcription and expression which leads to their high plasma level. The frequency of the TNF-α (-308) and LT-α (+ 252) polymorphisms are different for NHL and ALL cases in various populations with different ethnicity. This research is designed to investigate the prevalence and association of TNF-α (-308) and LT-α (+ 252) polymorphisms from NHL and ALL in Azarian patients and healthy individuals from Northwestern part of Iran. MATERIALS AND METHODS: Seventy subjects with ALL and 68 NHL, along with another 130 healthy subjects as control group took part in this study. Genomic DNA was extracted, then genetic polymorphisms in TNF-α and LT-α genes were analyzed with the PCR-RFLP and NCOI as restriction enzyme. A statistical analysis was performed by chi-square test using SPSS software. A P-value of <0.05 was considered statistically significant. RESULTS: A statistically significant difference of LT-α polymorphism was in NHL patients and control (P-value= 0.008) but there was not any association of TNF-α polymorphism between NHL patients and control group. A significant association for TNF-a variant was in ALL and control (P-value =0.005), however, there was no relationship about LT variant between ALL and control. CONCLUSION: The results show that there are significant differences between TNF-α (-308) and LT-α (+252) genetic polymorphisms respectively in ALL and NHL patients with control group from Northwestern part of Iran.