In Vivo Safety and Regeneration of Long-Term Transported Amniotic Fluid Stem Cells for Renal Regeneration

BACKGROUND: Despite major progress in stem cell therapy, our knowledge of the characteristics and tissue regeneration potency of long-term transported cells is insufficient. In a previous in vitro study, we established the optimal cell transport conditions for amniotic fluid stem cells (AFSCs). In the present study, the target tissue regeneration of long-term transported cells was validated in vivo. METHODS: For renal regeneration, transported AFSCs were seeded on a poly(lactide-co-glycolide) scaffold and implanted in a partially resected kidney. The target tissue regeneration of the transported cells was compared with that of freshly harvested cells in terms of morphological reconstruction, histological microstructure reformation, immune cell infiltration, presence of induced cells, migration into remote organs, expression of inflammation/fibrosis/renal differentiation-related factors, and functional recovery. RESULTS: The kidney implanted with transported cells showed recovery of total kidney volume, regeneration of glomerular/renal tubules, low CD4/CD8 infiltration, and no occurrence of cancer during 40 weeks of observation. The AFSCs gradually disappeared and did not migrate into the liver, lung, or spleen. We observed low expression levels of proinflammatory cytokines and fibrotic factors; enhanced expression of the genes Wnt4, Pax2, Wt1, and Emx2; and significantly reduced blood urea nitrogen and creatinine values. There were no statistical differences between the performance of freshly harvested cells and that of the transported cells. CONCLUSION: This study demonstrates that long-term transported cells under optimized conditions can be used for cell therapy without adverse effects on stem cell characteristics, in vivo safety, and tissue regeneration potency.

In Vivo Validation Model of a Novel Anti-Inflammatory Scaffold in Interleukin-10 Knockout Mouse

BACKGROUND: We fabricated anti-inflammatory scaffold using Mg(OH)2-incorporated polylactic acid-polyglycolic acid copolymer (MH-PLGA). To demonstrate the anti-inflammatory effects of the MH-PLGA scaffold, an animal model should be sensitive to inflammatory responses. The interleukin-10 knockout (IL-10 KO) mouse is a widely used bowel disease model for evaluating inflammatory responses, however, few studies have evaluated this mouse for the anti-inflammatory scaffold. METHODS: To compare the sensitivity of the inflammatory reaction, the PLGA scaffold was implanted into IL-10 KO and C57BL/6 mouse kidneys. Morphology, histology, immunohistochemistry, and gene expression analyses were carried out at weeks 1, 4, 8, and 12. The anti-inflammatory effect and renal regeneration potency of the MH-PLGA scaffold was also compared to those of PLGA in IL-10 KO mice. RESULTS: The PLGA scaffold-implanted IL-10 KO mice showed kidneys relatively shrunken by fibrosis, significantly increased inflammatory cell infiltration, high levels of acidic debris residue, more frequent CD8-, C-reactive protein-, and ectodysplasin A-positive cells, and higher expression of pro-inflammatory and fibrotic factors compared to the control group. The MH-PLGA scaffold group showed lower expression of pro-inflammatory and fibrotic factors, low immune cell infiltration, and significantly higher expression of anti-inflammatory factors and renal differentiation related genes compared to the PLGA scaffold group. CONCLUSION: These results indicate that the MH-PLGA scaffold had anti-inflammatory effects and high renal regeneration potency. Therefore, IL-10 KO mice are a suitable animal model for in vivo validation of novel anti-inflammatory scaffolds.

Optimal Stem Cell Transporting Conditions to Maintain Cell Viability and Characteristics

BACKGROUND: The preservation of stem cell viability and characteristics during cell transport from the bench to patients can significantly affect the success of cell therapy. Factors such as suspending medium, time, temperature, cell density, and container type could be considered for transport conditions. METHODS: To establish optimal conditions, human amniotic fluid stem cells' (AFSCs) viabilities were analyzed under different media {DMEM(H), DMEM/F-12, K-SFM, RPMI 1640, α-MEM, DMEM(L), PBS or saline}, temperature (4, 22 or 37 ℃), cell density (1 × 10⁷ cells were suspended in 0.1, 0.5, 1.0 or 2.0 mL of medium) and container type (plastic syringe or glass bottle). After establishing the transport conditions, stem cell characteristics of AFSCs were compared to freshly prepared cells. RESULTS: Cells transported in DMEM(H) showed relatively higher viability than other media. The optimized transport temperature was 4 ℃, and available transport time was within 12 h. A lower cell density was associated with a better survival rate, and a syringe was selected as a transport container because of its clinical convenience. In compare of stem cell characteristics, the transported cells with established conditions showed similar potency as the freshly prepared cells. CONCLUSION: Our findings can provide a foundation to optimization of conditions for stem cell transport.

Potency of Human Urine-Derived Stem Cells for Renal Lineage Differentiation

Kidney is one of the most difficult organs for regeneration. Several attempts have been performed to regenerate renal tissue using stem cells, the results were not satisfactory. Urine is major product of kidney and contains cells from renal components. Moreover, urine-derived stem cells (USCs) can be easily obtained without any health risks throughout a patient's entire life. Here, we evaluated the utility of USCs for renal tissue regeneration. In this study, the ability of USCs to differentiate into renal lineage cells was compared with that of adipose tissue-derived stem cells (ADSCs) and amniotic fluid-derived stem cells (AFSCs), with respect to surface antigen expression, morphology, immunocytochemistry, renal lineage gene expression, secreted factors, immunomodulatory marker expression, in vivo safety, and renal differentiation potency. Undifferentiated USCs were positive for CD44 and CD73, negative for CD34 and CD45, and formed aggregates after 3 weeks of renal differentiation. Undifferentiated USCs showed high SSEA4 expression, while renal-differentiated cells expressed PAX2, WT1, and CADHERIN 6. In the stem/renal lineageassociated gene analysis, OCT4, SSEA4, and CD117 were significantly downregulated over time, while PAX2, LIM1, PDGFRA, E-CADHERIN, CD24, ACTB, AQP1, OCLN, and NPHS1 were gradually upregulated. In the in vivo safety evaluation, renal-differentiated USCs did not show abnormal histology. These findings demonstrated that USCs have a similar MSC potency, renal lineage-differentiation ability, immunomodulatory effects, and in vivo safety as ADSCs and AFSCs, and showed higher levels of growth factor secretion for paracrine effects. Therefore, urine and USCs can be one of good cell sources for kidney regeneration.

Hypoxia Enhances Cell Properties of Human Mesenchymal Stem Cells

Atmospheric (in vitro) oxygen pressure is around 150 mm Hg (20% O₂), whereas physiologic (in vivo) oxygen pressure ranges between 5 and 50 mm Hg (0.7–7% O₂). The normoxic environment in cell culture does not refer to a physiological stem cell niche. The aim of this study is to investigate the effect of oxygen concentration on cell properties of human mesenchymal stem cells (MSCs). We analyzed cell proliferation rate, senescence, immunophenotype, stemness gene expression and differentiation potency with human urine stem cells (USCs), dental pulp stem cells (DPSCs), amniotic fluid stem cells (AFSCs), and bone marrow stromal cells (BMSCs). USCs, DPSCs, AFSCs and BMSCs were cultured under either 5% O₂ hypoxic or 20% O₂ normoxic conditions for 5 days. MSCs cultured under hypoxia showed significantly increased proliferation rate and high percentage of S-phase cells, compared to normoxic condition. In real-time PCR assay, the cells cultured under hypoxia expressed higher level of Oct4, C-Myc, Nanog, Nestin and HIF-1α. In immunophenotype analysis, MSCs cultured under hypoxia maintained higher level of the MSC surface markers, and lower hematopoietic markers. Senescence was inhibited under hypoxia. Hypoxia enhances osteogenic differentiation efficiency compared to normoxia. Hypoxia showed enhanced cell proliferation rate, retention of stem cell properties, inhibition of senescence, and increased differentiation ability compared to normoxia.

Comparison of 5 Different Rat Models to Establish a Standard Animal Model for Research Into Interstitial Cystitis / 대한배뇨장애요실금학회지

PURPOSE: We evaluated 5 different rat models using different agents in order to establish a standard animal model for interstitial cystitis (IC) in terms of the functional and pathologic characteristics of the bladder. METHODS: Five IC models were generated in 8-week-old female Sprague-Dawley rats via transurethral instillation of 0.1M hydrogen chloride (HCl) or 3% acetic acid (AA), intraperitoneal injection of cyclophosphamide (CYP) or lipopolysaccharide (LPS), or subcutaneous injection of uroplakin II (UPK2). After generating the IC models, conscious cystometry was performed on days 3, 7, and 14. All rats were euthanized on day 14 and their bladders were obtained for histological and pro-inflammatory-related gene expression analysis. RESULTS: In the cystometric analysis, all experimental groups showed significantly decreased intercontraction intervals compared with the control group on day 3, but only the LPS and UPK groups maintained significantly shorter intercontraction intervals than the control group on day 14. The histological analysis revealed that areas with severe urothelial erosion (HCl, AA, and UPK) and hyperplasia (CYP and LPS), particularly in the UPK-treated bladders, showed a markedly increased infiltration of toluidine blue-stained mast cells and increased tissue fibrosis. In addition, significantly elevated expression of interleukin-1b, interleukin-6, myeloperoxidase, monocyte chemotactic protein 1, and Toll-like receptors 2 and 4 was observed in the UPK group compared to the other groups. CONCLUSIONS: Among the 5 different agents, the injection of UPK generated the most effective IC animal model, showing consequent urothelial barrier loss, inflammatory reaction, tissue fibrosis stimulation, and persistent hyperactive bladder.

The Efficacy and Safety of Collagen-I and Hypoxic Conditions in Urine-Derived Stem Cell Ex Vivo Culture

Upper urinary tract-derived urine stem cells (USCs) are considered a valuable mesenchymal stem cell source for autologous cell therapy. However, the reported culture condition for USCs is not appropriate for large-quantity production, because cells can show limited replicativity, senescence, and undesirable differentiation during cultivation. These drawbacks led us to reconstitute a culture condition that mimics the natural stem cell niche. We selected extracellular matrix protein and oxygen tension to optimize the ex vivo expansion of USCs, and compared cell adhesion, proliferation, gene expression, chromosomal stability, differentiation capacity, immunity and safety. Culture on collagen type I (ColI) supported highly enhanced USC proliferation and retention of stem cell properties. In the oxygen tension analysis (with ColI), 5% O₂ hypoxia showed a higher cell proliferation rate, a greater proportion of cells in the S phase of the cell cycle, and normal stem cell properties compared to those observed in cells cultured under 20% O₂ normoxia. The established reconstituted condition (ColI/hypoxia, USCs(recon)) was compared to the control condition. The expanded USCs(recon) showed highly increased cell proliferation and colony forming ability, maintained transcription factors, chromosomal stability, and multi-lineage differentiation capacity (neuron, osteoblast, and adipocyte) compared to the control. In addition, USCs(recon) retained their immune-privileged potential and non-tumorigenicity with in vivo testing at week 8. Therefore, reconstituted condition allows for expanded uUSC cell preparations that are safe and useful for application in stem cell therapy.

Extra-gastrointestinal Stromal Tumor on the Inner Urinary Bladder Wall

A gastrointestinal stromal tumor is the most common mesenchymal tumor of the gastrointestinal tract, and is diagnosed on the basis of the combined expression of CD34 and CD117 (C-kit protein). An extragastrointestinal stromal tumor of the urinary bladder is a very rare neoplasm. In this report, we describe a case of an extragastrointestinal stromal tumor originating from the inner surface of the urinary bladder. A 46-year-old man presented with an incident bladder mass, and he was diagnosed with an extragastrointestinal stromal tumor after transurethral resection of the bladder tumor. A tumor on the inner urinary bladder wall is an unusual presentation of an extragastrointestinal stromal tumor. The patient is doing well with no recurrence at 18 months after surgery.

Three Cases of Nodular Fasciitis in the Parotid Gland / 대한이비인후과학회지

Nodular fasciitis (NF) is a benign tumor-like fibroblastic proliferation, and there have only been few reports about NF involving the parotid gland. Here, we report our experience of three cases of NF in the parotid gland, as well as our evaluation of the diagnostic tools for NF in the parotid gland, such as fine-needle aspiration cytology (FNAC), CT, and clinicopathologic investigations. In the three cases observed, all had growing masses in the parotid gland, and the lesions showed heterogeneous or peripheral rim enhancement on the contrast-enhanced CT, which could have been misdiagnosed as parotid malignancy. On FNAC, the cells had an elongated spindle shape and contained variable amounts of stromal matrix, which could have caused misinterpreted as pleomorphic adenoma. We observed dense cellularity and varying amounts of collagenous stroma, and immunohistochemical staining revealed positive reactivity to CD10, CD34, and smooth muscle actin. NF should be considered in the differential diagnosis of benign and malignant parotid tumors.

Intravascular Cytotoxic T-Cell Lymphoma in a Young Immunocompetent Woman

Intravascular lymphoma (IVL) is a rare disorder characterized by the presence of large neoplastic lymphoid cells restricted to the lumens of small vessels with a predilection for the skin and the central nervous system. While the vast majority of cases involving IVL are of B-cell lineage, the disease rarely affects the T-cell, the histiocytes, and the natural killer cells. We report a case of intravascular T-cell lymphoma (IVTL) associated with Epstein-Barr virus (EBV). A 23-year-old healthy woman presented with tender indurated erythematous patches with overlying telangiectasia on her right breast, abdomen, both the upper and the lower extremities and the back for 3 months. The pathology revealed an infiltration of dermal and subcutaneous vessels by large and atypical lymphoid cells with immunohistochemical features of the T-cell lineage with a cytotoxic phenotype (CD3+, CD8+, granzyme B+, TIA-1+, CD4-, CD5-, CD20-, CD56-). Interestingly, the DNA extracted from the skin biopsies demonstrated evidence of a monoclonal immunoglobulin heavy chain gene rearrangement, but no T-cell receptor gene rearrangement was found. In situ hybridization study for EBV-encoded RNA was positive. She was diagnosed with an EBV-associated IVTL. The patient's skin lesions were refractory to the combination of chemotherapy and autologous stem cell transplant, and she expired. The findings in the present case may highlight the unique clinicopathologic aspects of EBV-associated cytotoxic IVTL that occurred in a young, immunocompetent woman.