This immunofluorescence photomicrograph uses the dye, fluorescein, attached to an antibody specific for a protein in eosinophil granules, called eosinophil major basic protein, to detect and locate eosinophils. It shows how the eosinophils (shown by the bright yellow/green colored areas) cluster around and along the hyphal growth (shown as faintly colored threads) of the fungus known as Alternaria. It also shows that the major basic protein has been released from eosinophils and has been localized on the surfaces of these fungal hyphae. These human eosinophils were incubated for several hours in a culture with live fungal hyphae before being fixed in formalin and stained with the specific antibody to eosinophil major basic protein. (Original Magnification X400)
This vividly colored quartet of images is an esthetic tribute to the work of certain graphic artists, and the colored enhancements were provided to the ADRL by the Mayo Rochester Section of Photography. Each identical image shows a view from a scanning electron microscope that provides a 3-dimensional perspective at very high magnification. The large sphere in the upper right is an eosinophil and the tube-like shape on the left is a part of a hyphal growth of the fungus Alternaria. There appears to be a substance coming from the eosinophil that is partially covering the fungus. One hypothesis under current testing is that eosinophils are part of an immune system attack response to certain microbes, including the fungus Alternaria.