Figure 4
From: Uptake and intra-inclusion accumulation of exogenous immunoglobulin by Chlamydia-infected cells
Bovine serum albumin does not accumulate within infected cells. Cells infected for 48 h with C. trachomatis serovar K (guinea pig anti-Chlamydia/TRITC-conjugated goat anti-guinea pig)(A) were probed for internalized BSA using a rabbit anti-BSA antibody and detected with FITC-conjugated goat anti-rabbit Ig (B). Unlike IgG, this abundant ~66 kDa polypeptide does not accumulate within the chlamydial inclusion, as apparent in the merge of Chlamydia and nuclear stains (C). A merge incorporating DIC imaging shows an identifiable inclusion and indicates no co-localization of the two immunolabels has occurred (D). This demonstrates that BSA is not subject to the same entry or sequestration as bovine IgG, indicative that the process of IgG internalization is selective. (bar = 10 μm).