Binding of the rifampicin-dependent antibodies to L βIX and L β cells.

The L βIX and L αβ cells were incubated with patient serum in the presence or absence of rifampicin, followed by an FITC-conjugated secondary antibody, and examined by flow cytometry. The patient serum did not bind in the absence of the drug (shaded peak). The patient serum bound to the L βIX cells (A) but not to the L αβ cells (B) in the presence of the drug. The shaded peak in each graph represents the binding of the serum in the absence of the drug. The figure illustrates the results from 1 experiment that is representative of the results observed on the 3 occasions the experiment was performed.