The Behaviour of Both Listeria monocytogenes and Rat Ciliated Ependymal Cells Is Altered during Their Co-Culture

Abstract

BackgroundCiliated ependymal cells line the cerebral ventricles and aqueducts separating the infected CSF from the brain parenchyma in meningitis.Principal FindingsInvestigation of the interaction of Listeria monocytogenes with cultured rat brain ependymal cells showed that certain strains reduced the beat frequency of the cilia but all the strains studied significantly reduced the ciliary beat amplitude (the linear distance travelled by the tip of each cilium per beat cycle).ConclusionThe presence of the ependyma caused aggregation of some listeria strains and in some cases extracellular material also was seen in association with bacterial aggregates. These observations were dependent on the expression of genes required for invasion, intracellular survival and listerial cell to cell spread that are regulated by the transcriptional activator, positive regulatory factor A (PrfA).

Chemical Basis of Interactions Between Engineered Nanoparticles and Biological Systems

“…First, different cell types have different shapes. Human erythrocytes exhibit a smooth, spherical shape, while ependymal cells demonstrate a long, slender shape. , These differences produce different cellular responses when internalizing foreign matter, such as nanoparticles. Second, plasma membranes from different cell types have different lipid compositions, which influence the physical properties of membranes and make them function differently.…”

In vivo and in vitro observation of nasal ciliary motion in a guinea pig model

“…10 We observed a slowly decreasing ciliary beat amplitude in vitro , without correlation with CBF. The dissociation of ciliary beat amplitude from beat frequency was reported by previous studies, 21 probably due to the different regulatory mechanism. 6…”

“…The CBD of in vitro cilia was determined by the distance between maximum power stroke and recovery stroke of the cilia tips. 21 In vivo CBD was determined by the distance travelled by the front edge of each ciliary wave also from its maximum recovery stroke to power stroke (Figure 3). At room temperature, 24°C, the baseline CBD was recorded at the start of each experiment and was defined as 100%.…”

Ciliary functional analysis: Beating a path towards standardization

“…There is a lack of agreement concerning the CBA definition . CBA has been defined as the distance travelled between the maximum forward and backwards movements of the cilia tip, or as the angle between the cilium body in the end position of an effective stroke and a recovery stroke (which is only an indicator of the CBA, due to the flexible nature of the beat) …”