Zebrafish Xenografts for the In Vivo Analysis of Healthy and Malignant Human Hematopoietic Cells

: The zebrafish is a powerful vertebrate model for genetic studies on embryonic development and organogenesis. In the last decades, zebrafish were furthermore increasingly used for disease modeling and investigation of cancer biology. Zebrafish are particularly used for mutagenesis and small molecule screens, as well as for live imaging assays that provide unique opportunities to monitor cell behavior, both on a single cell and whole organism level in real time. Zebrafish have been also used for in vivo investigations of human cells transplanted into embryos or adult animals; this zebrafish xenograft model can be considered as an intermediate assay between in vitro techniques and more time-consuming and expensive mammalian models.Here, we present a protocol for transplantation of healthy and malignant human hematopoietic cells into larval zebrafish; transplantation into adult zebrafish and possible advantages and limitations of the zebrafish compared to murine xenograft models are discussed.