Figure 4
A comparative approach based on using the “number of antibodies per structure” as a measure for immunostaining intensities. The intensity of the immunolabaled synaptosomes and structure of interest (here: cultured neuronal synapses) can be measured (upper panels). Fluorescent intensities from single antibodies absorbed to a glass coverslip and immunolabeled with the same secondary antibodies as used for the synaptosomes/synapses can be determined in parallel (lower panels). This makes it possible to express the intensity of labeled synaptosomes and structures of interest in terms of antibody copy numbers. This has been done by our laboratory for over 100 target proteins in synaptosomes, and can be done easily for any structure of interest by any other laboratory. Finally, intensities can be compared in terms of antibody copy numbers, and protein copy numbers can be calculated from this.
