Quantitative assessment of XXXX invasion in vivo.

@entity1313 @entity5 @entity39 @entity35 @entity204 @entity463
The aim of this study was the quantitative assessment of the time course and spatial distribution in brain of invading @entity463 ( @entity463 ) cells using a recently described model consisting of @entity35 @entity35 @entity463 cells stably transfected with enhanced green fluorescent protein (eGFP) - called RT2-eGFP - and implanted in Fischer @entity35 . Invasion throughout the brain was verified by confocal microscopy and immunocytochemical staining for eGFP. @entity35 were sacrificed on post-implantation days 3, 8, and @entity204 ( @entity204 ). First, the entire @entity35 brain was disaggregated at each time point and viable @entity35 -eGFP cells were counted using flow cytometry with fluorescence as the marker. Next, 2 mm(3) samples of cortex from each of four brain quadrants (bifrontal and bioccipital) were disaggregated at each time point, with @entity5 cell quantification as before. @entity5 cell density, averaged over the entire brain, reached a peak mid-way through its time course, leveling out by @entity204 . @entity5 cell density within @entity5 ( @entity5 ) was greatest early in the evolution of the @entity1313 , decreasing to its final value mid-way through its time course, due to @entity39 . The greatest concentration of @entity5 cells was within @entity5 , with up to an order of magnitude fewer cells in the periphery, while the number of @entity1313 cells invading brain distant from @entity5 remained constant from day 3 until @entity204 . @entity5 size steadily increased after implantation, with an increasing portion due to central @entity39 as time progressed, suggesting that this effect is an important contributor to fatality in this model. Alternatively (or additionally), accumulation of toxins elaborated by @entity5 cells throughout the brain starting early in the evolution of the @entity5 may also contribute to fatality.
