An optical platform for cell tracking in adult zebrafish

Abstract

Adult zebrafish are being increasingly used as a model in cancer and stem cell research. Here we describe an integrated optical system that combines a laser scanning confocal microscope (LSCM) and an in vivo flow cytometer (IVFC) for simultaneous visualization and cell quantification. The system is set up specifically for non-invasive tracking of both stationary and circulating cells in adult zebrafish (casper) that have been engineered to be optically transparent. Confocal imaging in this instrument serves the dual purpose of visualizing fish tissue microstructure and an imaging-based guide to locate a suitable vessel for quantitative analysis of circulating cells by IVFC. We demonstrate initial testing of this novel instrument by imaging the transparent adult zebrafish casper vasculature and tracking circulating cells in CD41-GFP/Gata1-DsRed transgenic fish whose thrombocytes/erythrocytes express the green and red fluorescent proteins. In vivo measurements allow cells to be tracked under physiological conditions in the same fish over time, without drawing blood samples or sacrificing animals. We also discuss the potential applications of this instrument in biomedical research. ' 2011 International Society for Advancement of Cytometry

The Neural Crest and Cancer: A Developmental Spin on Melanoma

“…Further investigation revealed that the aggressive melanoma cells secreted Nodal, (a potent embryonic morphogen), responsible for the ectopic induction of the embryonic axis [Topczewska et al, 2006]. Thus, although the zebrafish embryo is extremely useful as a biosensor for tumor cell signals [Topczewska et al, 2006; Stewart et al, 2010; Zhang et al, 2012], one of the major limitations of this system is the lack of surgical accessibility to manipulate or transplant tissue at various developmental stages.…”

“…In vivo imaging strategies of the tumor microenvironment represent an intense area of study that has benefitted from new technological advances in multiphoton microscopy, fluorescent reporters of cell cycle progression, and unique windowing techniques into the living adult mouse and chick and zebrafish embryos [Condeelis and Weissleder, 2010; Fukumura et al, 2010; Giampieri et al, 2010; Friedl and Alexander, 2011; Zhou, 2011; Zhang et al, 2012]. Thus, in vivo imaging is providing unique access to tumor cell behaviors in natural microenvironments (Table 1).…”

Simple and Rapid Quantification of Thrombocytes in Zebrafish Larvae

“…This strain expresses green fluorescent protein (GFP) under regulation of the cd41 promoter, and it has been used for multiple studies that have led to novel insights into platelet function. 3,8,9 Quantitative analysis of thrombocytes has relied on in vivo or ex vivo flow cytometry 14,15 or peripheral blood smears. 10 However, these methods usually require euthanasia for blood collection and/or timeconsuming and expensive analyses.…”

Imaging innate immune responses at tumour initiation: new insights from fish and flies

“…Yet, we know from studies in mice and humans that the adaptive immune system is heavily involved in surveillance and potential killing of cancer cells, so perhaps zebrafish could offer insight here too. There are now good reporter lines for T and B cells 51,52 and, just as later-stage larval and adult fish are now being used to image skin healing 53 , it will also be possible to live image immune cell interactions with pre-neoplastic cells at these later stages, perhaps with the additional aid of translucent adult lines such as casper 54 . This should help determine when adaptive immune cells first interact with a growing clone of pre-neoplastic cells and what the involvement of innate immune cells might be in highlighting their presence.…”