Anti-MBP monoclonal antibody, clone 509DU28.5.4

The acute toxicity of high concentrations of carbon dioxide (CO2) was investigated in anesthetized rats using physiological parameters. At an oxygen concentration of 21%, the survival time decreased in a concentration-dependent manner from 7.3 h at 20% CO2 to 1.0 h at 50% CO2. The animals were divided into groups that were exposed to 40% CO2 and 21% O-2 balanced with nitrogen (CO2 group), 40% CO2 and 12.6% O-2 (CO2 Hypoxia group), 0% CO2 and 12.6% O-2 (Hypoxia group), and 0% CO2 and 21% O-2 (Control group) for 3 h. In the CO2 group, mean blood pressure (MBP) increased temporarily in the first 60 min followed by a gradual decrease, while breathing rate (BR) decreased immediately up to 3 h and the concentration of serum indicators reflecting organ damage increased. Most of these effects progressed in the CO2-Hypoxia group. The Hypoxia group showed a contrasting response to the CO2 groups in MBP and BR, and a slight partial increase in the serum indicators. Histological changes were not observed in any primary organs of any group, except for eosinophilic or necrosis of pyramidal cells in the hippocampal CA1 region of the CO2 group. These results indicate that high concentrations of CO2 inhalation are toxic, likely due to BR suppression, and that hypoxia produced under a high CO2 environment, while showing little effect on its own, enhances the toxic effects of CO2.

Living matter is a quasi-stationary out-of-equilibrium system; in this physical condition, structural fluctuations at nano- and meso-scales are needed to understand the physics behind its biological functionality. Myelin has a simple ultrastructure whose fluctuations show correlated disorder in its functional out-of-equilibrium state. However, there is no information on the relationship between this correlated disorder and the dynamics of the intrinsically disordered Myelin Basic Protein (MBP) which is expected to influence the membrane structure and overall functionality. In this work, we have investigated the role of this protein structural dynamics in the myelin ultrastructure fluctuations in various conditions, by using synchrotron Scanning micro X Ray Diffraction and Small Angle X ray Scattering. We have induced the crossover from out-of-equilibrium functional state to in-equilibrium degeneration changing the pH to values far from physiological condition. The observed compression of the cytosolic layer thickness probes that the intrinsic large MBP fluctuations preserve the cytosol structure also in the degraded state. Thus, the transition of myelin ultrastructure from correlated to uncorrelated disordered state, is principally affected by the deformation of the membrane and extracellular domain.