Protective role of functionalized single walled carbon nanotubes enhance ex vivo expansion of hematopoietic stem and progenitor cells in human umbilical cord blood

In this study, carboxylic acid functionalized single walled carbon nanotubes (f-SWCNT-COOH) was shown to support the viability and ex vivo expansion of freeze-thawed, non-enriched hematopoietic stem and progenitor cells (HSPC) in human umbilical cord blood–mononucleated cells (UCB-MNC). Our in vitro experiments showed that f-SWCNT-COOH increased the viability of the CD45+ cells even without cytokine stimulation. It also reduced mitochondrial superoxides and caspase activity in CD45+ cells. f-SWCNT-COOH drastically reduced the proportions of CD45− cells in the non-enriched UCB-MNC. Phenotypic expression analysis and functional colony forming units (CFU) showed significant ex vivo expansion of HSPC, particularly of CD45+CD34+CD38− population and granulocyte-macrophage (GM) colonies, in f-SWCNT-COOH augmented cultures supplemented with basal cytokines. In vivo data suggested that f-SWCNT-COOH expanded UCB-MNC could repopulate immunodeficient mice models with minimal acute or sub-acute symptoms of graft-versus-host disease (GVHD) and f-SWCNT-COOH dependent toxicity.From the Clinical EditorIn this paper a novel method is presented by using single wall functionalized carbon nanotubes to enhance viability and ex vivo expansion of freeze-thawed, non-enriched hematopoietic stem and progenitor cells in human umbilical cord blood -mononucleated cells. Detailed data is presented about enhanced viability, including improved repopulation of immunodeficient mice models with minimal acute or sub-acute symptoms of graft-versus-host disease.

In this study, we carried out a hitherto unreported use of carboxylic acid functionalized single walled carbon nanotubes (f-SWCNT-COOH) to support the viability and ex vivo expansion of freeze-thawed, non-enriched hematopoietic stem and progenitor cells (HSPC) in human umbilical cord blood–mononucleated cells (UCB-MNC). In vitro phenotypic and functional studies showed that f-SWCNT-COOH supported viability; reduced mitochondrial reactive oxygen species (ROS); and enhanced ex vivo expansion of viable HSPC in a concentration dependent manner. In vivo studies suggested that f-SWCNT-COOH expanded UCB-MNC could repopulate immunodeficient mice models without exhibiting any acute or sub-acute form of SWCNT mediated toxicity.Figure optionsDownload high-quality image (159 K)Download as PowerPoint slide