Characterization of membranous vesicles in OLF.

<p><b>A</b>) Protocol used to isolate oviductal exosomes by ultracentrifugation of oviductal fluids. <b>B</b>) TEM of negative staining for the particulate fraction from OLF reveals the presence of membranous vesicles ranging in size from 25-100 nm in diameter. <b>C</b>) Western blots detected CD9 (24 kDa) in protein extracts from membranous vesicles removed from OLF and uterosomes, but not in the supernatants. Testis protein was used as a positive control. Each lane contains 40 µg of protein. Results are representative of three different experiments. <b>D</b>) Immunogold labeling (6 nm gold particles) of CD9 is shown in oviductal membranous vesicles termed “oviductosomes”. Gold particles on individual oviductosomes are seen arrowed in 2-6 on the exterior of the membrane. In the absence of primary antibodies and the presence of rat IgG, gold particles were absent (1), indicating the specificity of the antibody. Scale bar =100 nm in panel B, D.