Article

W/Wv marrow stromal cells engraft and enhance early erythropoietic progenitors in unconditioned Sl/Sld murine recipients.

Toronto General Research Institute, Toronto, ON, Canada.
Bone Marrow Transplantation (Impact Factor: 3.54). 01/2003; 30(12):867-72. DOI: 10.1038/sj.bmt.1703761
Source: PubMed

ABSTRACT Transplantation of marrow stromal cells may provide a means of modulating hematopoiesis and serve as a form of cell therapy. We employed a murine transplant model using Sl/Sl(d) mice, which have macrocytic anemia due to defective expression of stem cell factor (SCF) on bone marrow stromal cells. Donor cells were derived from the complementary mutant strain W/W(v), which also exhibit anemia, due to mutations in c-kit, the SCF receptor expressed on hematopoietic stem cells. The strength of this model is that any correction of the Sl/Sl(d) anemia from the infusion of W/W(v) stromal cells can be attributed to the effect of the stromal cells and not to contaminating W/W(v) hematopoietic stem cells, a major concern in experiments involving wild-type animals. Cultured stromal cells were infused into unconditioned non-splenectomized Sl/Sl(d) mice. Engraftment of donor stromal cells reached levels of up to 1.0% of total marrow cells 4 months post transplant. However, stromal engraftment was not detectable in the spleen. Recipients of W/W(v) stroma showed a significant increase in the committed erythroid progenitors compared with those receiving Sl/Sl(d) stromal cells: 109 +/- 26 vs 68 +/- 5 CFU-E per 10(5) BMC, P = 0.002; 25 +/- 10 vs 15 +/- 5 BFU-E per 10(5) BMC, P = 0.037, for W/W(v) and Sl/Sl(d) stroma recipients, respectively. Despite this increase in erythroid progenitors, the anemia was not corrected. Our data suggest that in this murine model, splenic erythropoiesis may influence stromal cell therapy, and that higher levels of marrow engraftment may be necessary to obtain a clinically significant effect.

0 Bookmarks
 · 
46 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: We previously showed the emergence of predominantly non-fused murine cells co-expressing cardiac and stromal determinants in co-cultures of murine mesenchymal stromal cells (MSCs) and rat embryonic cardiomyocytes. To determine whether a similar phenotype is detectable in vivo in ischemic myocardium, we infused green fluorescence protein (GFP)-marked MSCs intravenously into wild-type mice in an acute myocardial infarction (AMI) model generated by ischemia/reperfusion (I/R) or fixed coronary artery ligation. We found that infused GFP+ cells were confined strictly to ischemic areas and represented approximately 10 % of total cellularity. We showed that over 60 % of the cells co-expressed collagen type IV and troponin T or myosin heavy chain, characteristic of MSCs and cardiomyocytes, respectively, and were CD45(-). Nonetheless, up to 25 % of the GFP+ donor cells expressed one of two cardiomyocyte markers, either myosin heavy chain or troponin T, in the absence of MSC determinants. We also observed a marked reduction in OCT4 expression in MSCs pre-infusion compared with those lodged in the myocardium, suggesting reduced stem cell properties. Despite the low frequency of lodged donor MSCs, left-ventricular end-diastolic pressure was significantly better in experimental versus saline animals for both AMI (12.10 ± 1.81 vs. 20.50 ± 1.53 mmHg, p < 0.001) and I/R models (8.75 ± 2.95 vs. 17.53 ± 3.85 mmHg, p = 0.004) when measured 21 days after MSC infusion and is consistent with a paracrine effect. Our data indicate that donor MSCs undergo variable degrees of cardiomyocyte reprogramming with the majority co-expressing cardiomyocyte and stromal markers. Further studies are needed to elucidate the factors mediating the extent of cardiomyocyte reprogramming and importance of the cellular changes on tissue repair.
    Stem cell reviews 11/2013; · 5.08 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Introduction: Early reports demonstrated the safety of adherent mesenchymal stromal cell (MSC) infusions in the hematopoietic stem cell transplantation (HCT) setting, as well as clinical efficacy for treatment of steroid refractory acute graft-versus-host disease (GVHD); however, two large, Phase III randomized, placebo-controlled trials of MSC for initial therapy or steroid refractory GVHD failed to meet their primary endpoints of durable complete response. Subset analyses demonstrated efficacy in selected patient populations, contributing to recent approvals of MSC for pediatric patients in Canada and New Zealand. Areas covered: In this review, we discuss the biologic and immunomodulatory properties of MSC and potential mechanisms involved. We review the results of prior clinical trials incorporating MSC for GVHD treatment or prophylaxis, the recent approvals in Canada and New Zealand, as well as future directions in the field. Expert opinion: The role of MSC infusions, in the prophylaxis and/or treatment of GVHD after HCT, continues to be under active investigation. Whether, and how, to incorporate MSC infusions is unclear, and ongoing questions include the source tissue type and culture methods, the timing and dosage of MSC product infusions, as well as the optimal clinical trial design and endpoints for assessment of clinical response.
    Expert opinion on biological therapy 02/2014; 14(2):231-46. · 3.22 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Group V-secreted phospholipase A(2) (GV sPLA(2)) hydrolyzes bacterial phospholipids and initiates eicosanoid biosynthesis. Here, we elucidate the role of GV sPLA(2) in the pathophysiology of Escherichia coli pneumonia. Inflammatory cells and bronchial epithelial cells both express GV sPLA(2) after pulmonary E. coli infection. GV(-/-) mice accumulate fewer polymorphonuclear leukocytes in alveoli, have higher levels of E. coli in bronchoalveolar lavage fluid and lung, and develop respiratory acidosis, more severe hypothermia, and higher IL-6, IL-10, and TNF-α levels than GV(+/+) mice after pulmonary E. coli infection. Eicosanoid levels in bronchoalveolar lavage are similar in GV(+/+) and GV(-/-) mice after lung E. coli infection. In contrast, GV(+/+) mice have higher levels of prostaglandin D(2) (PGD(2)), PGF(2α), and 15-keto-PGE(2) in lung and express higher levels of ICAM-1 and PECAM-1 on pulmonary endothelial cells than GV(-/-) mice after lung infection with E. coli. Selective deletion of GV sPLA(2) in non-myeloid cells impairs leukocyte accumulation after pulmonary E. coli infection, and lack of GV sPLA(2) in either bone marrow-derived myeloid cells or non-myeloid cells attenuates E. coli clearance from the alveolar space and the lung parenchyma. These observations show that GV sPLA(2) in bone marrow-derived myeloid cells as well as non-myeloid cells, which are likely bronchial epithelial cells, participate in the regulation of the innate immune response to pulmonary infection with E. coli.
    Journal of Biological Chemistry 08/2011; 286(41):35650-62. · 4.65 Impact Factor

Full-text

View
0 Downloads
Available from