Figure 4. Influence of the temperature during 0.5% paraformaldehyde fixation. All corneal pieces were fixed for 30 min. Antigen retrieval with sodium dodecyl sulfate was efficient only for histone H3, but detached almost all endothelial cells from the Descemet membrane after fixation at 4 °C; the arrow indicates the single cell that remained attached. No pseudocolor for immunostaining; no counterstaining for nuclei. 40X objective.