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Adult neovascularization relies on the recruitment of circulating cells, but their angiogenic roles and recruitment mechanisms are unclear. We show that the endothelial growth factor VEGF is sufficient for organ homing of circulating mononuclear myeloid cells and is required for their perivascular positioning and retention. Recruited bone marrow-derived(More)
Although mesenchymal stromal cells (MSCs) exhibit marked immunoregulatory activity through multiple mechanisms, their potential to completely evade rejection upon transplantation into allogeneic recipients is controversial. To directly address this controversy, the survival of luciferase-labeled MSCs (Luc(+) MSCs) was evaluated by imaging in allogeneic(More)
Xenotransplantation of pig tissues has great potential to overcome the shortage of organ donors. One approach to address the vigorous immune rejection associated with xenotransplants is the use of embryonic precursor tissue, which induces and utilizes host vasculature upon its growth and development. Recently, we showed in mice that embryonic pig pancreatic(More)
Immature dendritic cells (imDCs) can have a tolerizing effect under normal conditions or after transplantation. However, because of the significant heterogeneity of this cell population, it is extremely difficult to study the mechanisms that mediate the tolerance induced or to harness the application of imDCs for clinical use. In the present study, we(More)
Previous studies suggest that cells within the CD34(+) hematopoietic stem cell compartment are endowed with immune regulatory activity. Furthermore, it is possible to expand the human regulatory cells upon short-term culture of purified CD34+ cells with an early-acting cytokine cocktail. We now show that addition of anti-CD28, anti-CD2, interleukin-2(More)
Graft-versus-host disease (GVHD) is uniformly lethal in recipients of HLA-mismatched marrow. In patients with severe combined immunodeficiency disease, this major obstacle can be overcome by rigorous T-cell depletion before transplantation. In leukaemia patients, however, the benefit of preventing GVHD is offset by graft rejection or graft failure. Very(More)
Studies in mice and humans demonstrate that transplantation of hematopoietic progenitors in numbers larger than commonly used ("megadose" transplants) overcomes major genetic barriers. In vitro studies suggest that veto cells, within the population of hematopoietic progenitors, facilitate this favorable outcome. Thus, when purified CD34(+) cells were added(More)
Several bone marrow cells and lymphocyte subpopulations, known as "veto cells," were shown to induce transplantation tolerance across major histocompatibility antigens. Recently, it has been suggested that anti-third party CTLs depleted of alloreactivity are endowed with marked veto activity and therefore might potentially facilitate bone marrow(More)
Repair of injured lungs represents a longstanding therapeutic challenge. We show that human and mouse embryonic lung tissue from the canalicular stage of development (20-22 weeks of gestation for humans, and embryonic day 15-16 (E15-E16) for mouse) are enriched with progenitors residing in distinct niches. On the basis of the marked analogy to progenitor(More)
The direct assay of veto CTLs in the 2C mouse model enables monitoring, by FACS, the fate of the TCR transgenic effector CD8(+) T cells, the transgene of which can be stained with clonotypic Ab 1B2. After the addition of veto cells, CD8(+)1B2(+) effector cells increasingly express annexin V, and maximal apoptosis is attained 72 h after initiation of MLR.(More)