Imaging Microtubuli in PFA-Fixed HeLa Cells

HeLa cell samples have been prepared using the PFA-fixation protocol outlined in [49 (link)]. Microtubuli have been stained using monoclonal mouse anti-β -tubulin (Sigma Aldrich) and goat anti-mouse IgG secondary antibody (ThermoFisher Scientific), labeled with Alexa Fluor 647 at 1:150 and 1:300 dilution, respectively. All imaging experiments have been conducted in imaging buffer prepared freshly from 150-200mM MEA (β-Mercapto-ethylamine hydrochloride) in PBS and pH adjusted to 7.4 using NaOH. The oxygen scavenging effect from MEA has been proven efficient enough to refrain from additional enzyme-based oxygen scavenger systems.