CD34+Corneal Stromal Cells Are Bone Marrow-Derived and Express Hemopoietic Stem Cell Markers

Abstract Transplanted bone marrow donor cells with tissue specific phenotypes have been found in the brain, liver, heart, skin, lung, kidney, and gut of transplanted humans and mice. Such observations have led to the controversial hypothesis that hematopoietic stem cells (HSC) might be intrinsically plastic, and through transdifferentiation or fusion lead to the repair of damaged tissues throughout the body. Alternately, it is suggested that fusion of macrophages to the recipient cells may explain this phenomenon. We have shown recently that purified HSC are the cells responsible for GFP positive donor-derived muscle fibers in the recipient mice post bone marrow transplantation. However, further studies sorting for macrophage markers Mac-1 and F4/80 also resulted in donor-derived muscle fibers in the host. To address this discrepancy, we investigated subpopulations of Mac-1 and F4/80 positive cells, in the presence or absence of stem cell markers (Sca-1 and C-kit). We demonstrate that only the subpopulations of Mac-1 and F4/80 positive cells harboring stem cell markers, Sca-1 or c-kit, were capable of contributing to the regenerating muscle post transplantation. Furthermore, these same subpopulations demonstrated single cell High Proliferative Potential (HPP) (6–26%) in a 7 factor cytokine cocktail, compared to the Mac-1 or F4/80 cells with no stem cell markers (0%). Additionally, they demonstrated long-term engraftment in all three lineages at 1-year (average chimerism of 55% versus 0% in stem cell marker negative groups). These subpopulations were also evaluated for morphology using Hematoxylin/Eosin (H/E), Wright-Giemsa, and Nonspecific Esterase staining. In the Mac-1 and F4/80 positive groups, those negative for stem cell markers resembled differentiated cells of the myeloid origin (macrophages, granulocytes), while those with positive stem cell markers demonstrated stem cell characteristics. We did not observe any engraftability, donor-derived muscle fibers, or HPP potential for CD14 or cfms positive cells coexpressing stem cell markers, indicating that these markers are more appropriate for identifying macrophages. In conclusion, our studies demonstrate that both Mac-1 and F4/80 surface markers are present on HSC and therefore caution must be taken in the interpretation of data using these macrophage markers. It is reasonable to believe that the use of Mac-1 and/or F4/80 surface markers in a lineage depletion process may result in the loss of a subpopulation of stem cells, and other markers such as CD14 or c-fms may be more appropriate for eliminating differentiated macrophages.

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DNA Methylation-Based Regulation of Human Bone Marrow-Derived Mesenchymal Stem/Progenitor Cell Chondrogenic Differentiation

Cells Tissues Organs ◽

10.1159/000502885 ◽

2019 ◽

Vol 207 (3-4) ◽

pp. 115-126 ◽

Cited By ~ 2

Author(s):

Yu Nomura ◽

Emilio Satoshi Hara ◽

Yuya Yoshioka ◽

Há Thi Nguyen ◽

Shuji Nosho ◽

...

Keyword(s):

Tissue Engineering ◽

Bone Marrow ◽

Stem Cell ◽

Chondrogenic Differentiation ◽

Stem Cell Differentiation ◽

Human Bone ◽

Human Bone Marrow ◽

Cartilage Tissue ◽

Stem Cell Markers ◽

Cell Markers

Stem cells have essential applications in in vitro tissue engineering or regenerative medicine. However, there is still a need to understand more deeply the mechanisms of stem cell differentiation and to optimize the methods to control stem cell function. In this study, we first investigated the activity of DNA methyltransferases (DNMTs) during chondrogenic differentiation of human bone marrow-derived mesenchymal stem/progenitor cells (hBMSCs) and found that DNMT3A and DNMT3B were markedly upregulated during hBMSC chondrogenic differentiation. In an attempt to understand the effect of DNMT3A and DNMT3B on the chondrogenic differentiation of hBMSCs, we transiently transfected the cells with expression vectors for the two enzymes. Interestingly, DNMT3A overexpression strongly enhanced the chondrogenesis of hBMSCs, by increasing the gene expression of the mature chondrocyte marker, collagen type II, more than 200-fold. Analysis of the methylation condition in the cells revealed that DNMT3A and DNMT3B methylated the promoter sequence of early stem cell markers, NANOG and POU5F1(OCT-4). Conversely, the suppression of chondrogenic differentiation and the increase in stem cell markers of hBMSCs were obtained by chemical stimulation with the demethylating agent, 5-azacitidine. Loss-of-function assays with siRNAs targeting DNMT3A also significantly suppressed the chondrogenic differentiation of hBMSCs. Together, these results not only show the critical roles of DNMTs in regulating the chondrogenic differentiation of hBMSCs, but also suggest that manipulation of DNMT activity can be important tools to enhance the differentiation of hBMSCs towards chondrogenesis for potential application in cartilage tissue engineering or cartilage regeneration.

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Factors contained in the expansion medium regulate the expression stem cell markers CD146 and SUSD2 on human placenta‐derived mesenchymal stromal cells and modulate their differentiation capacity in vitro

The FASEB Journal ◽

10.1096/fasebj.2019.33.1_supplement.495.1 ◽

2019 ◽

Vol 33 (S1) ◽

Author(s):

Tanja Abruzzese ◽

Wilhelm K Aicher

Keyword(s):

Stem Cell ◽

Mesenchymal Stromal Cells ◽

Human Placenta ◽

Stromal Cells ◽

Stem Cell Markers ◽

Cell Markers ◽

Differentiation Capacity ◽

Expansion Medium

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Evaluation of Minnelide As a Potential Therapeutic Agent for Preventing the Relapse of AML

Blood ◽

10.1182/blood-2019-123567 ◽

2019 ◽

Vol 134 (Supplement_1) ◽

pp. 5159-5159

Author(s):

Pooja Roy ◽

Bhuwan Giri ◽

Vanessa Tonin Garrido ◽

Dujon Brandon Edwards ◽

Justin M. Watts ◽

...

Keyword(s):

Bone Marrow ◽

Stem Cell ◽

Board Of Directors ◽

Tumor Burden ◽

Fold Change ◽

Water Soluble ◽

Stem Cell Markers ◽

Advisory Committees ◽

Cell Markers

BACKGROUND: Acute myeloid leukemia (AML) is the most common acute leukemia amongst adults which requires multiple phases and combinations of chemotherapeutic agents. Despite this complex regimen, most patients either fail to achieve remission or relapse. Triptolide, a diterpenoid triepoxide compound and Minnelide its water-soluble prodrug have shown significant efficacy in decreasing leukemic burden in preclinical animal models. In the current study, we evaluated the potential of Minnelide to prevent recurrence of AML via its effect on leukemic stem cells and in the bone marrow. METHODS: To determine the effect of triptolide on the stemness of AML cells, two chemotherapy-resistant cell lines (THP-1 and KG-1) were treated overnight with triptolide at a dose of 2.5nM and 25nM. The colonies formed per well were subsequently measured. Stem cell markers (CD47, CD95, CD126 and TIM3) were also measured after treatment with various doses of triptolide (5nM, 10nM, 25nM). We also carried out in-vivo experiments in which luciferase-tagged THP-1 cells were intravenously injected into NSG mice. Positively implanted mice were then treated intraperitoneally with either saline or Minnelide (0.15mg/kg/day) for 30 days. RESULTS: Triptolide treated cells had significantly reduced number of colonies per well in a colony formation assay, indicating decreased clonogenicity. In addition, treatment with triptolide reduced expressed of stem cell markers CD47 and CD126 at a concentration of 20nM (fold change of 0.3 and 0.55 for CD47 and fold change of 0.14 and 0.66 for CD126 for THP-1 and KG-1 respectively). In-vivo, Minnelide was able to successfully reduce tumor burden as evidenced by serial measurements of radiance (ROI) with IVIS. Furthermore, bone marrow histology of Minnelide treated mice resembled the bone marrow of non-diseased animals. Analysis with flow cytometry supported our findings showing a significant reduction of human CD45RA positive cells in the bone marrow of Minnelide treated mice. CONCLUSION: Minnelide is not only successful in reducing tumor burden but it is potentially an effective therapy for preventing relapse of AML. This is evidenced by the reduction in stemness of AML cells treated with triptolide and through the reduction in tumor burden in the bone marrow of mice treated with low doses of Minnelide. FIGURE 1: Bone marrow from Minnelide treated mice had a significantly reduced infiltration of myeloid cells compared to saline treated mice and even resembled negative controls. Figure 1 Disclosures Watts: Pfizer: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Takeda: Research Funding; Jazz Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Banerjee:Minneamrita Therapeutics LLC: Consultancy. Saluja:Minneamrita Therapeutics, LLC: Other: Co-founder and the Chief Scientific Officer.

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Human and rodent bone marrow mesenchymal stem cells that express primitive stem cell markers can be directly enriched by using the CD49a molecule

Cell and Tissue Research ◽

10.1007/s00441-006-0292-3 ◽

2006 ◽

Vol 327 (3) ◽

pp. 471-483 ◽

Cited By ~ 36

Author(s):

F. Gindraux ◽

Z. Selmani ◽

L. Obert ◽

S. Davani ◽

P. Tiberghien ◽

...

Keyword(s):

Stem Cells ◽

Bone Marrow ◽

Mesenchymal Stem Cells ◽

Stem Cell ◽

Stem Cell Markers ◽

Cell Markers ◽

Marrow Mesenchymal Stem Cells

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268.Identifying markers for stromal stem/progenitor cells in human endometrium

Reproduction Fertility and Development ◽

10.1071/srb04abs268 ◽

2004 ◽

Vol 16 (9) ◽

pp. 268 ◽

Cited By ~ 1

Author(s):

K. E. Schwab ◽

C. E. Gargett

Keyword(s):

Flow Cytometry ◽

Stem Cell ◽

Progenitor Cells ◽

Stromal Cells ◽

Stromal Cell ◽

Endometrial Tissue ◽

Cell Populations ◽

Stem Cell Markers ◽

Endometrial Stromal Cell ◽

Cell Markers

The endometrium is divided into upper functionalis, which rapidly grows then differentiates before being shed, and lower basalis, from which cyclical regeneration begins. A small proportion of endometrial stromal cells have been identified with clonogenic activity, a functional property of stem cells (1). We hypothesised that stromal stem/progenitor cells expressing known stem cell markers reside in the basalis. The aims of this study were to: (1) investigate the clonogenic activity of human endometrial stromal cell populations enriched and depleted for known stem cell markers, and (2) identify a marker that will differentiate basalis from functionalis stroma. Endometrial tissue acquired from 23 ovulating women undergoing hysterectomy was digested with collagenase to produce single cell suspensions. Leukocytes and epithelial cells were removed, and stromal cells analysed by flow cytometry, FACS sorted into enriched and depleted populations, and cultured for clonal analysis as described (1). Markers analysed included stem cell markers, STRO-1, CD133, CD45 and CD34, and an endometrial stromal cell marker, CD90 (2). Immunohistochemical analysis of CD90 was performed on full thickness human endometrial tissue. CD45– endometrial stromal cell populations contained 2.13 � 0.65% (n = 13) STRO-1+, and 5.43 � 1.42% (n = 16) CD133+ cells. Stromal cell populations enriched (0.65 � 0.42%) and depleted (0.95 � 0.58%) for STRO-1 showed no significant difference (P = 0.19, n = 5) for clonogenic activity. Surprisingly, clonogenicity of CD133+ stromal cells (0.74 � 0.56%) was lower than CD133– (3.89 � 1.35%) cells (P = 0.03, n = 6). Immunohistochemical staining showed strong CD90 staining in the functionalis, with lighter staining in the basalis. These observations were confirmed by flow cytometric analysis which identified two distinct populations (n = 9), CD90low (19.55 � 4.35%) and CD90hi (74.71 � 5.20%). Clonogenic analysis of these two populations is underway. Interestingly, dual-colour flow cytometry showed the CD133+ cells to be CD90low (n = 7). Further analysis suggests that the CD90lowCD133+ population are CD45–CD34+, suggesting endothelial progenitor cells. This study identified CD90 as a marker that distinguishes basalis and functionalis stroma, and demonstrated that STRO-1 and CD133 are not functional markers for clonogenic endometrial stromal stem/progenitor cells. (1) Chan RW, Schwab KE, Gargett CE (2004) Biol. Reprod. 70, in press. (2) Fernandez-Shaw S, Shorter SC, Naish CE, Barlow DH, Starkey PM (1992) Hum. Reprod. 7,156–161.

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