Abstract
Organ cultures of 10 Fallopian tubes were inoculated with a genital strain of Chlamydia trachomatis and seven were infected. Infection was enhanced by centrifuging the organisms on to the tissues, larger numbers of organisms being reisolated from the tissues after this procedure. There was evidence of chlamydial multiplication because the number of organisms which were recovered from the tissues three to five days after inoculation had increased. Recovery was rare, however, after the sixth day, thus suggesting a self-limiting infection. Organ cultures of two bovine oviducts were infected with the bovine abortion strain of Chlamydia psittaci, but in these experiments centrifugation of the inocula did not enhance infection. The organisms were found in both the tissue and medium of cultures up to 18 days after inoculation and in much greater numbers than in the C. trachomatis-infected Fallopian cultures. Chlamydial infection was not entirely host-tissue specific, because C. trachomatis organisms were isolated from bovine oviduct cultures. Inclusions, however, were not detected histologically or electron microscopically in the epithelium of C. trachomatis-infected cultures, but they were detected by these means in C. psittaci-infected bovine cultures. All the elements of the chlamydial growth cycle were seen by electron microscopy, organisms being found in ciliated and possibly non-ciliated cells, and shedding of some infected epithelial cells was observed. No evidence of extensive epithelial cell damage was observed, however, and no loss of ciliary activity was detected in cultures infected with either C. trachomatis or C. psittaci when compared with uninoculated cultures. Thus acute salpingitis, when caused by chlamydial infection, is probably immunologically mediated.