PrismPlus: a mouse line expressing distinct fluorophores in four different brain cell types

Abstract

To screen the complex central nervous system (CNS) injury responses, we created a quadruple-labelled ‘PrismPlus’ mouse line with a genetically encoded distinct fluorescent tag in oligodendrocytes, microglia, neurons, and astrocytes. Cx3cr1-gfp and Prism mice originally developed by Jung et al., 2000 and Dougherty et al., 2012, respectively, were cross-bred. First, we confirmed the presence of fluorophores in appropriate cell types in PrismPlus mice. PrismPlus mice were then used to examine the cellular responses to brain implanted micro-devices. We observed an increase in microglial response at earlier time points as compared to 4 weeks, a progressive astrocytic response, and fewer neurons at the vicinity of an implanted device. These results are similar to what has been described in literature using other rodent strains, previously attainable only through time-consuming and variable immunohistochemistry methods. Finally, we demonstrate the compatibility of PrismPlus brain tissue with CLARITY, an advanced tissue clearing technique, opening the door to future thick tissue imaging studies. This report confirms PrismPlus transgenic fluorescence and highlights the utility of these mice to study CNS injuries. The work herein seeks to establish a novel transgenic mouse line to improve experimental scope, consistency, and efficiency for CNS researchers.

Multicolor three-photon fluorescence imaging with single-wavelength excitation deep in mouse brain

“…Multicolor 3PM can also be applied to other combinations of fluorescent molecules upon 1340-nm excitation, even for fluorescent molecules that do not exhibit large cross-section enhancement. Figure 4 shows multicolor brain imaging of a PrismPlus mouse ( 29 ) that expresses cyan fluorescent protein (CFP; Cerulean) in oligodendrocytes, enhanced green fluorescent protein (EGFP) in microglia, yellow fluorescent protein (YFP) in neurons, and DsRed-Max in astrocytes, using a single excitation wavelength at 1340 nm. DsRed-Max is a less cytotoxic variant of DsRed ( 30 ).…”

“…4 , a PrismPlus transgenic mouse [ Cx3cr1 tm1Litt Tg(Prism)1989Htz/J, JAX stock number 031478 ( 29 ), female, 8 weeks old, 19 g] was used. The PrismPlus transgenic mouse expresses CFP (Cerulean) in oligodendrocytes, EGFP in immune cells including microglia, YFP in nucleolus and cytoplasm of neuronal soma, and DsRed-Max in astrocytes ( 29 ). For Fig.…”

Tissue Response to Neural Implants: The Use of Model Systems Toward New Design Solutions of Implantable Microelectrodes

“…Mice carrying cell specific fluorescent tags have been shown to provide great advantages in the study of the contribution of different cells in a single animal as well as a valuable alternative to immunostaining steps (Sunshine et al, 2018; Eles et al, 2019). Gaire and colleagues recently developed a quadruple-labeled mouse with specific fluorescent tags for oligodendrocytes, microglia, neurons, and astrocytes and investigate the process of nervous tissue response to “Michigan” array silicon microelectrodes (Gaire et al, 2018b).…”

Features Of Hippocampal Astrocytic Domains And Their Spatial Relation To Excitatory And Inhibitory Neurons

“…Recently developed brain clearing techniques allow large scale, three dimensional, single-cell resolution characterization of multiple cell types simultaneously (Gradinaru et al, 2018;Treweek and Gradinaru, 2016;Ye et al, 2016). Such methods can be adopted to investigate astrocytic domains, and indeed a few studies have already used transgenic mice to show that fluorescent astrocytes can be imaged in the cleared mouse cortex (Chai et al, 2017;Gaire et al, 2018;Lanjakornsiripan et al, 2018;Miller and Rothstein, 2016). However, the number of reconstructed astrocytes in these works remained very low, and their territories were defined in most cases by their envelope surfaces, rather than by the detailed morphology of their filaments.…”