Fig. 7.

CdtA and CdtC are enriched in detergent-resistant membrane (DRM) fractions. CHO-K1 cells were left untreated or treated with 10 mM MβCD for 1 h prior to incubation with C. jejuni CDT holotoxin (200 nM) for 2 h at 37°C. The cells then were subjected to cold detergent extraction using 1% Triton X-100, followed by centrifugation to separate the DRM and detergent-soluble (S) fractions. (A) Each fraction was subjected to Western blot analysis using antibodies against caveolin-1 and CD71 and individual antisera specific to CdtA, CdtB, and CdtC. The results are representative of one of three independent experiments. (B) The protein expression levels were analyzed using scanning densitometry. The protein expression levels represent the relative distribution (percent) of each protein within the DRM and soluble fractions. MβCD, methyl-β-cyclodextrin.