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This paper focuses on the development of renewable sources of isletreplacement tissue for the treatment of type I diabetes mellitus. Placental tissue-derived mesenchymal stem cells (MSCs) are a promising source for regenerative medicine due to their plasticity and easy availability. They have the potential to differentiate into insulin-producing cells. miR-375 is a micro RNA that is expressed in the pancreas and involved in islet development. Human placental decidua basalis MSCs (PDB-MSCs) were cultured from full-term human placenta. The immunophenotype of the isolated cells was checked for CD90, CD105, CD44, CD133 and CD34 markers. The MSCs (P3) were chemically transfected with hsa-miR-375. Total RNA was extracted 4 and 6 days after transfection. The expressions of insulin, NGN3, GLUT2, PAX4, PAX6, KIR6.2, NKX6.1, PDX1, and glucagon genes were evaluated using real-time qPCR. On day 6, we tested the potency of the clusters in response to the high glucose challenge and assessed the presence of insulin and NGN3 proteins via immunocytochemistry. Flow cytometry analysis confirmed that more than 90% of the cells were positive for CD90, CD105 and CD44 and negative for CD133 and CD34. Morphological changes were followed from day 2. Cell clusters formed during day 6. Insulin-producing clusters showed a deep red color with DTZ. The expression of pancreatic-specific transcription factors increased remarkably during the four days after transfection and significantly increased on day 7. The clusters were positive for insulin and NGN3 proteins, and C-peptide and insulin secretion increased in response to changes in the glucose concentration (2.8 mM and 16.7 mM). In conclusion, the MSCs could be programmed into functional insulin-producing cells by transfection of miR-375.
Objective: There is increasing evidence that the transplanted bone marrow stromal cells (BMSC) significantly promote functional recovery after central nervous system damage in the animal models of various kinds of CNS disorders, including cerebral infarct. However, there are several shortages of information when considering clinical application of BMSC transplantation for patients with neurological disorders. In this meeting, therefore, we discuss what we should clarify to establish cell transplantation therapy in clinical situation and describe our recent works for this purpose. Methods and Results: The BMSC have multiple abilities to differentiate into the neural cells and to promote neuronal survival and axon elongation, contributing to rebuild the neural circuits in the injured CNS. Using optical imaging and MRI techniques, the transplanted BMSC can non-invasively be tracked in the living animals for at least 8 weeks after transplantation. Clinical MR apparatus can visualize the tagged BMSC in the brain. FDG PET is quite valuable to monitor the recovery of brain metabolism after transplantation. The BMSC can be expanded using the animal protein-free culture medium within a clinically relevant period. G-CSF is useful to enhance their proliferation when the BMSC are obtained from the aged patients. There are optimal dose and timing of BMSC transplantation to yield significant therapeutic benefits. Conclusion: It is urgent issues to develop clinical imaging technique to track the transplanted cells in the CNS and evaluate the therapeutic significance of BMSC transplantation to establish it as a definite therapeutic strategy in clinical situation in very near future.
Tremendous efforts have been made to ameliorate and improve locomotor function after spinal cord injury (SCI) by the transplantation of various types of stem cells. In our study we compared the use of non-neurogenic stem cells – bone marrow stromal cells (MSCs), an immortalized stem cell line (SPCs) derived from human fetal spinal cord tissue or human induced pluripotent stem cell-derived neural precursors (iPS-NPs) – for the treatment of a balloon-induced spinal cord compression lesion. Suspensions of stem cells were implanted into the lesion one week after SCI, while the control groups were injected with saline. Locomotor and sensitivity tests were performed weekly for two months. Animals transplanted with any cell type displayed significant motor and sensory improvement compared to the controls. Morphometric evaluation showed that the white matter was spared in all grafted animals when compared to controls, while the gray matter was spared only in animals implanted with MSCs or iPS-NPs. Two months post-implantation (PI), all types of grafted cells survived in the lesion; however, MSCs, unlike iPS-NPs and SPCs, did not differentiate nor communicate with the host tissue. Compared to SPCs, which partially filled the lesion cavity, iPS-NPs interacted more with the host tissue. Besides differentiating into MAP2-, 5TH- and Dcx-positive neurons, iPS-NPs differentiated into CNPase+ oligodendrocytes. A few cells expressed ChAT, while others were DARPP32+ . SPCs expressed mainly GFAP; however, already at two months PI we found 25% of the cells to be positive for Nkx 6.1, and at four months PI the cells were positive for ChAT and Islet2, motor neuron-specific markers. qPCR revealed the increased expression of rat and human neurotrophin genes as well as human motor neuron-specific genes. Based on staining for GAP43, SPCs cells supported endogenous neurite sprouting and regeneration. Another important therapeutic goal is treating chronic SCI, possibly by a combination of stem cells and bridging scaffolds. Hydrogel bridges seeded with MSCs were implanted into SCI one month after injury. The implanted rats were behaviorally tested, then sacrificed 6 months PI and the spinal cord lesions histologically evaluated. The hydrogels adhered well to the surrounding tissue and completely filled the post-traumatic cavity. MSCs survived in the hydrogel, and neurofilaments, blood vessels and Schwann cells infiltrated the implant. Combined therapy also prevented tissue atrophy, while behavioral analysis showed an improvement in rats with combined treatment, compared with the control group. Our results demonstrate that the transplantation of neurogenic as well as non-neurogenic stem cells into the lesioned rat spinal cord improves functional outcome by providing trophic support to the spared axons in the injured tissue. Neurogenic stem cells have the ability to interact with the host tissue and differentiate into a more mature phenotype, such as motor neurons. Treatment of chronic spinal cord injury will require a combination of cell therapy and lesion bridging. Supported by IAA500390902, GA CR: P304/12/1370, GA CR: P108/10/1560.
Human adipose-derived stem cells (huADSC) were generated from fat tissue of a 65-year-old male donor. Flow cytometry and reverse transcription polymerase chain reaction (RT-PCR) analyses indicated that the huADSC express neural cell proteins (MAP2, GFAP, nestin and β-III tubulin), neurotrophic growth factors (BDNF and GDNF), and the chemotactic factor CXCR4 and its corresponding ligand CXCL12. In addition, huADSC expressed the characteristic mesenchymal stem cell (MSC) markers CD29, CD44, CD73, CD90, CD105 and HLA class I. The huADSC were employed, via a right femoral vein injection, to treat rats inflicted with experimental intracerebral hemorrhage (ICH). Behavioral measurement on the experimental animals, seven days after the huADSC therapy, showed a significant functional improvement in the rats with stem cell therapy in comparison with rats of the control group without the stem cell therapy. The injected huADSC were detectable in the brains of the huADSC treated rats as determined by histochemistry analysis, suggesting a role of the infused huADSC in facilitating functional recovery of the experimental animals with ICH induced stroke.
The goal of this study was to evaluate the effect of various concentrations of interferon-tau (IFN-τ) with or without steroid hormones, 17ß estradiol or progesterone, on the proliferation of bovine endometrial cells in vitro. Endometrial epithelial and stromal cells were isolated from the uterus of cows during the early estrus cycle (2-3 days) and incubated with different doses of IFN-τ with or without steroid hormones. The proliferation was determined by the MTT test in 48, 96, and 144 h of incubation. An antiproliferative activity of IFN-τ was observed both in epithelial and stromal cells cultured in RPMI 1640 medium supplemented with 10% FBS or serum replacement. However, epithelial cells were more sensitive to antiproliferative action of interferon-tau. It;s activity was dose- and time-dependent. The inhibition of epithelial cell proliferation by 50% (ED50) was achieved at concentrations of 500 U/ml, 340 U/ml, and 8.8 U/ml of IFN-τ after 48, 96, and 144 h of incubation, respectively. None of the doses of IFN-τ (10-10.000 U/ml) used inhibited stromal cell proliferation in 50%. The most effective dose of IFN-τ inhibiting stromal cell proliferation was 10.000 U/ml, which decreased cell growth by 17.08%, 22.87%, and 2.6% after 48, 96, and 144 h of incubation, respectively. Steroid hormones, 17ß estradiol and progesterone, added to the culture of stromal cells with or without IFN-τ did not significantly modulate stromal cell growth. In contrast, a high concentration of progesterone (10-5M) alone significantly enhanced stromal cell growth. Progesterone at low, physiological concentrations (107 - 10-9 M) ameliorated the antiproliferative activity of IFN-τ, especially at the 109 M concentration. At this concentration, the stimulatory effect on stromal cell growth was observed. The mechanisms of such response are not entirely clear but may arise from the influence of IFN-τ on progesterone down regulation of its own receptor. Depicted activity of IFN-τ may find usefulness in therapy of neoplastic disorders.
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