Homing of in vitro expanded Stro-1- or Stro-1+ human mesenchymal stem cells into the NOD/SCID mouse and their role in supporting human CD34 cell engraftment

Abstract

IntroductionRecent results have shown that cotransplantation of human ex vivo-expanded mesenchymal stem cells (MSCs) together with hematopoietic stem cells hastens hematopoietic recovery following a bone marrow (BM) transplantation in animal models [1][2][3][4] and in humans. [5][6][7] Human BM contains 2 cell compartments, the hematopoietic cell compartment and the stromal cell compartment, which constitute MSCs. 8,9 MSCs are able to give rise to multiple mesodermal tissue types, including bone, cartilage, tendon, muscles, cardiomyocytes, fat, and brain, 10-16 and a marrow stromal connective tissue that supports the differentiation of hematopoietic stem cells (HSCs). 17,18 However, MSCs are heterogeneous, and little is known on the role of MSC subsets in the hematopoietic engraftment support and in their homing in various tissues. 19 Stro-1 antigen is present on fibroblast colony-forming unit (CFU-F) cells in adult human BM and potentially defines a MSC precursor subpopulation. [20][21][22] The aim of the present study was to evaluate the role of ex vivo-expanded Stro-1 ϩ and Stro-1 Ϫ MSCs on engraftment of human CD34 ϩ cord blood cells in nonobese diabetic/ severe combined immunodeficiency (NOD/SCID) mice. Our data showed that the levels of human hematopoietic engraftment (as assessed by the presence of CD45, CD34, CD19, and CD11b cells) in the blood, spleen, and mouse BM were higher when Stro-1 Ϫ -derived cells were coinfused with CD34 ϩ cells than when Stro-1 ϩ -derived cells were used.In a second step, we investigated the homing of expanded Stro-1 ϩ and Stro-1 Ϫ cells (infused without CD34 ϩ cells) in BM, spleen, liver, brain, heart, lungs, kidneys, and muscles of NOD/ SCID mice. Eight-week-old NOD/SCID mice received 3.5 Gy irradiation, and 24 hours later the cells were infused. We analyzed the homing of cells by polymerase chain reaction (PCR) quantitation of DNA of human ␤-globin. Results showed that the DNA amount from expanded Stro-1 ϩ cells was higher than that of expanded Stro-1 Ϫ cells in spleen (ϫ 8), muscles (ϫ 6), BM (ϫ 2), liver (ϫ 1.5), and kidneys (ϫ 1.5). No significant difference was observed in brain, while more Stro-1 Ϫ than Stro-1 ϩ cell DNA was found in lungs (ϫ 3.5).In conclusion, expanded Stro-1 ϩ cells better migrated than expanded Stro-1 Ϫ cells in most mouse tissues. This indicated that Stro-1 ϩ cells would be potentially a good vector to bring specific therapeutic genes into tissues. To test this hypothesis, we infused into NOD/SCID mice expanded Stro-1 ϩ cells transfected with an enhanced green fluorescent protein (eGFP) gene. The specific eGFP DNA was found in every investigated tissue-namely, BM, liver, brain, heart, spleen, kidneys, muscles, and lungs. Patients, materials, and methods Collection and isolation of CD34 ؉ cells from human umbilical cord blood (hUCB)Human umbilical cord blood (hUCB) samples were obtained from full-term deliveries after informed consent of the mother and were used in accordance with the procedures approved by the human experimentation and ethics com...

Magnetic Resonance Imaging of Single Co-Labeled Mesenchymal Stromal Cells after Intracardial Injection in Mice

“…Therefore, respiratory gating of mice on human MR scanners remains challenging [46]. The ability to detect co-labeled MSC up to the single cell level in-vivo appears interesting to investigate homing and local engraftment of these cells because after systemic administration only a small percentage of transplanted MSC can be detected in the bone marrow and different organs [47]. In this study in-vivo imaging of single cells could be achieved by using a clinical 3.0 T MR system and a commercially available mouse receiver coil.…”

“…A general limitation of this study was the use of murine cells only. Homing of human MSC in immunodeficient mice has been demonstrated [47,53] and offers unique perspectives for in-vivo cell tracking studies in mouse models. The proposed co-labeling technique and MR imaging protocol are much likely also applicable to human MSC but have to be specifically investigated.…”

Mesenchymal stem cells in human placental chorionic villi reside in a vascular Niche

“…Importantly, these antibody markers were used to define the MSC niche in these tissues. Furthermore, in these studies the STRO-1, 3G5 and CD146 antibodies were able to enrich for subpopulations of progenitor MSCs [15,[18][19][20][21][22] that have a high capacity to form fibroblastoid colonies in vitro (called the CFU-F population) [22], which is an important property of stem cells. CFU-F colonies derive from a single stem cell and have the ability to differentiate into many of the cells types that are characteristically derived from the niche [23].…”

Co-transplantation of third-party umbilical cord blood-derived MSCs promotes engraftment in children undergoing unrelated umbilical cord blood transplantation

“…31,32 In addition, MSCs have been found in BM after systemic infusion in an animal model and can enhance the engraftment of HSCs. [33][34][35] These results suggest that MSCs can home to BM and support hematopoiesis. However, other recent studies have suggested that soluble factors released by MSCs may also have a role in the enhancement of HSC engraftment based on the observations of faint and transient engraftment of MSCs after systemic infusion.…”