Human polymorphonuclear leucocytes (
HPMN) were incubated with [35S]
methionine-labelled Chlamydia trachomatis (serovar L2/434/Bu) elementary bodies (EB) and EB cell walls. No net loss in the TCA-precipitable radioactivity was observed over 24 h in the
HPMN that had taken up EB cell walls. SDS-
polyacrylamide gel electrophoresis of the labelled C. trachomatis EB and EB cell wall
proteins extracted from the
HPMN at 2 and 24 h after
infection demonstrated the persistence of most of the chlamydial cell wall
polypeptides. Analysis of extracts of the
HPMN that had taken up either EB or EB cell walls on
Urografin density gradients at 2 and 24 h after
infection, and electron microscopic observations on fractions representing the peaks, demonstrated the persistence of the EB cell walls in the
HPMN. Electron microscopic observations of
HPMN that had taken up EB or EB cell walls demonstrated EB cell walls in the
HPMN phagosomes at 24 h after
infection. The
HPMN exposed to EB and EB cell walls of C. trachomatis gave chemiluminescent (CL) responses with peaks respectively 12 and 7 times greater than the peak value of the control. The significance of the persistence of the EB cell wall
polypeptides and cell walls in the
HPMN and activation of the
HPMN to produce
oxygen radicals (i.e. a CL response), and its possible relation to
rheumatic diseases, is discussed.