Micropatterned macrophage analysis reveals global cytoskeleton constraints induced by Bacillus anthracis edema toxin.

Bacillus anthracis secretes the edema toxin (ET) that disrupts the cellular physiology of endothelial and immune cells, ultimately affecting the adherens junction integrity of blood vessels that in turn leads to edema. The effects of ET on the cytoskeleton, which is critical in cell physiology, have not been described thus far on macrophages. In this study, we have developed different adhesive micropatterned surfaces (L and crossbow) to control the shape of bone marrow-derived macrophages (BMDMs) and primary peritoneal macrophages.

Two-photon intravital imaging of lungs during anthrax infection reveals long-lasting macrophage-dendritic cell contacts.

The dynamics of the lung immune system at the microscopic level are largely unknown because of inefficient methods of restraining chest motion during image acquisition. In this study, we developed an improved intravital method for two-photon lung imaging uniquely based on a posteriori parenchymal tissue motion correction. We took advantage of the alveolar collagen pattern given by the second harmonic generation signal as a reference for frame registration.

Cytoskeleton as an emerging target of anthrax toxins.

Bacillus anthracis, the agent of anthrax, has gained virulence through its exotoxins produced by vegetative bacilli and is composed of three components forming lethal toxin (LT) and edema toxin (ET). So far, little is known about the effects of these toxins on the eukaryotic cytoskeleton. Here, we provide an overview on the general effects of toxin upon the cytoskeleton architecture.

[Methods and models for percutaneous absorption studies of organophosphates].

Organophosphates are highly toxic compounds, mainly penetrating the organism through the percutaneous route. In this context, having topical skin protectant capable of limitating their percutaneous penetration is of crucial importance for exposed people. Knowledge of the toxicokinetic parameters corresponding to the percutaneous penetration of these compounds is a key step for the development of these protective formulations.