False-color imaging. Immunohistochemical detection of pHp in HOPE-fixed, paraffin embedded human lung tissues. Image-acquisition was performed using a Leica DM-LB2-microscope with 40x PL-Fluotar optics and a Leica DFC 320 camera with Leica software (Leica Microsystems, Germany). White balance, and contrast were adjusted using FixFoto (Koopmann, Germany). A: Same as Figure 1B (400x), B: the same specimen with color inversion; pHp now in blue color (400X), C and D: Two other examples of color-inverted photomicrographs showing a film of pHp in the intended position of the surfactant in human alveoli (400x). Examples of more than 10 experiments.