Figure 6.

Impact of the sample preparation on indirect immunolabeling after alkaline pre-treatment. Transverse stem sections of A. thaliana have been incubated for 2 h with either phosphate buffer (pH 7.2) or sodium carbonate (Na₂CO₃) (pH 11.4) prior indirect immunolabeling with the LM18 antibody. As represented in this figure, the alkaline pre-treatment results in an increase of LM18 detection regardless of the how the samples were prepared. (A,D) Section embedded in resin and cut with an ultramicrotome. (B,E) Sections embedded in wax and cut with a microtome. (C,F) Sections coated in agarose and cut with a vibratome. (A–C) were incubated with phosphate buffer (pH 7.2) prior to immunolabeling with the LM18 homogalacturonan antibody. (D–F) were pre-treated with Na₂CO₃ (pH 11.4) prior to immunolabeling with the LM18 antibody. The parameters used to capture these micrographs were identical between the pre-treatments. However, the time of exposure differed for each method of sample preparation. cp, cortical parenchyma; pp, pith parenchyma. Scale bar: 70 μm.