Immunohistochemical localization of tick Porin and Cytochrome c.

<p>The results showed that Porin levels were lower in infected than in uninfected tick salivary glands but demonstrated that differences in Cytochrome c levels were not at the protein level but in the localization of Cytochrome c, which was distributed in the cell cytoplasm of uninfected tick salivary glands but was mainly localized within organelles that probably corresponded to mitochondria in <i>A</i>. <i>phagocytophilum</i>-infected tick salivary glands. (A) Representative images of immunofluorescence analysis of uninfected and <i>A</i>. <i>phagocytophilum</i>-infected adult female tick salivary glands. Tick tissues were stained with rabbit anti-tick proteins antibodies (green, FITC). Arrows show positive staining in response to anti-Porin and anti-Cytochrome c IgG not present after incubation with preimmune IgG. (a-b) preimmune control serum-treated cells, which gave similar results between uninfected and infected ticks. (c-d) uninfected and infected cells stained with anti-Porin antibodies. (e-f) uninfected and infected cells stained with anti-Cytochrome c antibodies. (g-h) uninfected and infected cells stained with DAPI. Bars, 10 μm. (B) Sections in the red squares in e-h were magnified 5X and superimposed to illustrate the localization of the Cytochrome c in the cytoplasm of uninfected and infected adult female tick salivary glands. Arrows show positive staining. (C) Model of the Porin-mediated inhibition of Cytochrome c release as the anti-apoptotic mechanism to facilitate bacterial infection of tick salivary glands.