FIG. 5.

Immunoelectron microscopic visualization of 106- and 37-kDa proteins in ultrathin sections of E. chaffeensis-infected DH82 cells. Bar, 0.5 μm. (A) The 106-kDa protein is located at the surfaces of ehrlichiae (arrows) and in intramorular fibrils originating from the ehrlichial cell surfaces (arrowheads). Gold particle label is also seen on the membrane limiting ehrlichial inclusions (morulae). n, host cell nucleus. (B) Gold particle label with antibodies to the 37-kDa protein is localized in the ehrlichial cell cytoplasm (arrowhead) and in the periplasmic space (arrows).