ABSTRACT
Recessive dystrophic epidermolysis bullosa (RDEB) is an intractable genetic blistering skin disease in which the epithelial structure easily separates from the underlying dermis because of genetic loss of functional type VII collagen (Col7) in the cutaneous basement membrane zone. Recent studies have demonstrated that allogeneic bone marrow transplantation (BMT) ameliorates the skin blistering phenotype of RDEB patients by restoring Col7. However, the exact therapeutic mechanism of BMT in RDEB remains unclear. In this study, we investigated the roles of transplanted bone marrow-derived circulating mesenchymal cells in RDEB (Col7-null) mice. In wild-type mice with prior GFP-BMT after lethal irradiation, lineage-negative/GFP-positive (Lin(-)/GFP(+)) cells, including platelet-derived growth factor receptor α-positive (PDGFRα(+)) mesenchymal cells, specifically migrated to skin grafts from RDEB mice and expressed Col7. Vascular endothelial cells and follicular keratinocytes in the deep dermis of the skin grafts expressed SDF-1α, and the bone marrow-derived PDGFRα(+) cells expressed CXCR4 on their surface. Systemic administration of the CXCR4 antagonist AMD3100 markedly decreased the migration of bone marrow-derived PDGFRα(+) cells into the skin graft, resulting in persistent epidermal detachment with massive necrosis and inflammation in the skin graft of RDEB mice; without AMD3100 administration, Col7 was significantly supplemented to ameliorate the pathogenic blistering phenotype. Collectively, these data suggest that the SDF1α/CXCR4 signaling axis induces transplanted bone marrow-derived circulating PDGFRα(+) mesenchymal cells to migrate and supply functional Col7 to regenerate RDEB skin.
Subject(s)
Bone Marrow Transplantation , Collagen Type VII/metabolism , Epidermolysis Bullosa Dystrophica/metabolism , Epidermolysis Bullosa Dystrophica/pathology , Mesenchymal Stem Cell Transplantation , Animals , Cell Separation , Chemokine CXCL12/metabolism , Disease Models, Animal , Enzyme-Linked Immunosorbent Assay , Flow Cytometry , Fluorescent Antibody Technique , Mice , Mice, Inbred C57BL , Mice, Knockout , Real-Time Polymerase Chain Reaction , Receptor, Platelet-Derived Growth Factor alpha/metabolism , Receptors, CXCR4/metabolism , Signal Transduction/physiology , Skin TransplantationABSTRACT
The physiological role of "endogenous" bone marrow (BM) mesenchymal stromal cells (MSCs) in tissue regeneration is poorly understood. Here, we show the significant contribution of unique endogenous BM-MSC populations to muscle regeneration in Duchenne muscular dystrophy (DMD) mice (mdx). Transplantation of BM cells (BMCs) from 10-week-old mdx into 3-4-week-old mdx mice increased inflammation and fibrosis and reduced muscle function compared with mdx mice that received BMCs from 10-week-old wild-type mice, suggesting that the alteration of BMC populations in mdx mice affects the progression of muscle pathology. Two distinct MSC populations in BM, that is, hematopoietic lineage (Lin)(-) /ckit(-) /CD106(+) /CD44(+) and Lin(-) /ckit(-) /CD106(+) /CD44(-) cells, were significantly reduced in 10-week-old mdx mice in disease progression. The results of a whole-transcriptome analysis indicated that these two MSC populations have distinct gene expression profiles, indicating that the Lin(-) /ckit(-) /CD106(+) /CD44(+) and Lin(-) /ckit(-) /CD106(+) /CD44(-) MSC populations are proliferative- and dormant-state populations in BM, respectively. BM-derived Lin(-) /CD106(+) /CD44(+) MSCs abundantly migrated to damaged muscles and highly expressed tumor necrosis factor-alpha-stimulated gene/protein-6 (TSG-6), an anti-inflammatory protein, in damaged muscles. We also demonstrated that TSG-6 stimulated myoblast proliferation. The injection of Lin(-) /ckit(-) /CD106(+) /CD44(+) MSCs into the muscle of mdx mice successfully ameliorated muscle dysfunction by decreasing inflammation and enhancing muscle regeneration through TSG-6-mediated activities. Thus, we propose a novel function of the unique endogenous BM-MSC population, which countered muscle pathology progression in a DMD model.
Subject(s)
Bone Marrow Cells/physiology , Mesenchymal Stem Cells/physiology , Muscles/pathology , Muscular Diseases/pathology , Animals , Bone Marrow Cells/metabolism , Cell Movement/physiology , Cell Proliferation/physiology , Cells, Cultured , Mesenchymal Stem Cells/metabolism , Mice , Mice, Inbred C57BL , Mice, Inbred mdx , Muscular Diseases/metabolismABSTRACT
A 52-year-old woman with a history of two parturitions presented with lower abdominal pain. Multi-detector CT of the abdomen showed discontinuity of the sigmoid colon near the broad ligament on the left side. We assigned a provisional diagnosis of an internal hernia progressing through a defect in the broad ligament. SILS revealed a total broad ligament defect on the left side but no signs of ischemic, necrotic bowel. We successfully repaired the broad ligament defect with suturing. At the 2-month follow-up, the patient remained well with no signs of recurrence. This case appears to be the first report of a broad ligament hernia successfully diagnosed and repaired by SILS.
Subject(s)
Broad Ligament , Hernia, Abdominal/surgery , Herniorrhaphy , Laparoscopy , Female , Hernia, Abdominal/diagnosis , Humans , Middle AgedABSTRACT
Bone marrow mesenchymal stromal cells (BM-MSCs) have been demonstrated to contribute to tissue regeneration. However, chronic pathological conditions, such as diabetes and aging, can result in a decreased number and/or quality of BM-MSCs. We therefore investigated the maintenance mechanism of BM-MSCs by studying signaling through the receptor for advanced glycation end products (RAGE), which is thought to be activated under various pathological conditions. The abundance of endogenous BM-MSCs decreased in a type 2 diabetes mellitus (DM2) model, as determined by performing colony-forming unit (CFU) assays. Flow cytometric analysis revealed that the prevalence of the Lin-/ckit-/CD106+/CD44- BM population, which was previously identified as a slow-cycling BM-MSC population, also decreased. Furthermore, in a streptozotocin-induced type 1 DM model (DM1), the CFUs of fibroblasts and the prevalence of the Lin-/ckit-/CD106+/CD44- BM population also significantly decreased. BM-MSCs in RAGE knockout (KO) mice were resistant to such reduction induced by streptozotocin treatment, suggesting that chronic RAGE signaling worsened the maintenance mechanism of BM-MSCs. Using an in vitro culture condition, BM-MSCs from RAGE-KO mice showed less proliferation and expressed significantly more Nanog and Oct-4, which are key factors in multipotency, than did wild-type BM-MSCs. Furthermore, RAGE-KO BM-MSCs showed a greater capacity for differentiation into mesenchymal lineages, such as adipocytes and osteocytes. These data suggested that RAGE signaling inhibition is useful for maintaining BM-MSCs in vitro. Together, our findings indicated that perturbation of BM-MSCs in DM could be partially explained by chronic RAGE signaling and that targeting the RAGE signaling pathway is a viable approach for maintaining BM-MSCs under chronic pathological conditions.
Subject(s)
Bone Marrow Cells/metabolism , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Experimental/pathology , Mesenchymal Stem Cells/metabolism , Receptor for Advanced Glycation End Products/metabolism , Signal Transduction , Animals , Cell Count , Cell Differentiation , Cell Proliferation , Diabetes Mellitus, Type 1/metabolism , Diabetes Mellitus, Type 1/pathology , Disease Models, Animal , Mice, Inbred C57BL , Mice, KnockoutABSTRACT
High-mobility group box 1 (HMGB1) mobilizes platelet-derived growth factor receptor alpha-positive (PDGFRα(+)) mesenchymal cells from bone marrow (BM) into circulation. However, whether HMGB1-induced endogenous PDGFRα(+) mesenchymal cells stimulate skin regeneration has been unclear. Here, we investigated the functions of the HMGB1/BM-PDGFRα(+) mesenchymal cell axis in the regeneration of mouse skin grafts. We found that intravenous HMGB1 administration induced an accumulation of endogenous BM-PDGFRα(+) mesenchymal cells followed by significant inflammatory suppression in the grafts. In contrast, mice with reduced BM-PDGFRα(+) mesenchymal cells showed massive inflammation of the grafts compared to mice that had normal levels of these cells even after HMGB1 administration, suggesting that BM-PDGFRα(+) mesenchymal cells contribute to the HMGB1-induced anti-inflammatory effect. We also found that intravenously administered HMGB1 augmented the local migration of BM-PDGFRα(+) mesenchymal cells from circulation to skin graft by inducing the expression of CXCR4, an SDF-1 receptor, on these cells. Finally, we showed the therapeutic activity of the HMGB1/BM-PDGFRα(+) mesenchymal cell axis in an allergic contact dermatitis model. The results illustrated the contribution of the HMGB1/BM-PDGFRα(+) mesenchymal cell axis in suppressing the inflammation of injured/inflamed skin. These findings may provide future perspectives on the use of HMGB1-based medicines for intractable diseases.