FluoroMyelin™ Red is a bright, photostable and non-toxic fluorescent stain for live imaging of myelin

Abstract

FluoroMyelin™ Red is a commercially available water-soluble fluorescent dye that has selectivity for myelin. This dye is marketed for the visualization of myelin in brain cryosections, though it is also used widely to stain myelin in chemically fixed tissue. Here we have investigated the suitability of FluoroMyelin™ Red as a vital stain for live imaging of myelin in myelinating co-cultures of Schwann cells and dorsal root ganglion neurons. We show that addition of FluoroMyelin™ Red to the culture medium results in selective staining of myelin sheaths, with an optimal staining time of 2 hours, and has no apparent adverse effect on the neurons, their axons, or the myelinating cells at the light microscopic level. The fluorescence is bright and photostable, permitting long-term time-lapse imaging. After rinsing the cultures with medium lacking FluoroMyelin™ Red, the dye diffuses out of the myelin with a half life of about 130 minutes resulting in negligible fluorescence remaining after 18–24 hours. In addition, the large Stokes shift exhibited by FluoroMyelin™ Red makes it possible to readily distinguish it from popular and widely used green and red fluorescent probes such as GFP and mCherry. Thus FluoroMyelin™ Red is a useful reagent for live fluorescence imaging studies on myelinated axons.

Revealing architectural order with quantitative label-free imaging and deep learning

“…We applied our image translation approach to the task of predicting myelination in the developing human brain across different ages. Myelination is visualized using lipophilic organic dye FluoroMyelin that preferentially binds to myelin (51).…”

Live-cell imaging of neurofilament transport in cultured neurons

“…More recently, we have been working predominantly with high-density long-term myelinating co-cultures of DRG neurons and Schwann cells, which are maintained for up to several months in NbActiv4 ™ Myelination Medium (Table 3) (e.g. Monsma and Brown, 2012; Monsma et al, 2014). Given how well the myelinating cultures fare in the NbActiv4 ™ Culture Medium, we suspect that this medium may be superior to the L-15 Culture Medium for short-term low-density cultures also, but we have not yet tested this.…”

“…The neuron is co-expressing mCherry (to permit observation of the axons prior to photoactivation) and PAGFP-NFM. The culture was stained with FluoroMyelin ™ Red, which is a vital fluorescent marker for compact myelin (Monsma and Brown, 2012). A, B.…”

Requirements, desired characteristics and architectural proposal for a visualization framework for digital pathology

“…Today already some fluorescent stains [11] are used in digital pathology that are (by definition) very saturated and that cannot be visualized on display systems with small gamuts. Furthermore, also digital pathology is evolving and it is likely that in the future scanners will product hyperspectral data for which wide gamut displays can offer an added value.…”

“…It is expected that in the future available color gamut of displays will further increase because of introduction of new technologies such as multiprimary displays [9], OLED displays, and quantum dot backlights [10]. Figure 3: performance and specifications of display systems keep increasing over timeToday already some fluorescent stains [11] are used in digital pathology that are (by definition) very saturated and that cannot be visualized on display systems with small gamuts. Furthermore, also digital pathology is evolving and it is likely that in the future scanners will product hyperspectral data for which wide gamut displays can offer an added value.…”