Agent of Lymphogranuloma Venereum in the Lungs of Mice

Abstract

It has been shown 1 that the agent of lymphogranuloma venereum readily initiates a fatal infection when introduced into the yolk-sac of the developing chicken embryo, in contradistinction to the well known low-grade character of the infection which results when the virus is placed on the chorio-allantois. In the former site the minute “granulocorpuscles” 2 which are believed to represent elementary bodies of the agent are found in enormous numbers. With this source of abundant virus at hand the possibilities of intranasal infection in mice were investigated, as has also been done recently by Schoen 3 who employed virus propagated in the Ehrlich mouse sarcoma.

Two strains∗ of the lymphogranuloma venereum agent were studied in Swiss mice weighing usually less than 10 g. Ground suspensions of yolk-sacs heavily infected with virus were diluted tenfold with broth and centrifuged to throw down tissue fragments. 0.03 to 0.05 ml of supernatant was inoculated intranasally under light ether anesthesia. The mice which within 48 to 72 hours were manifestly ill with signs of marked respiratory involvement, were sacrificed; some died during this period. The former at autopsy showed, in one or more lobes, areas of semi-translucent gray-red consolidation varying in extent; the dead mice showed hemorrhagic consolidation of nearly all of the lung tissue. On microscopic examination of smears made by streaking a fragment of consolidated lung on a slide, fixing the film in methyl alcohol and staining with Giemsa stain, numerous elementary bodies could be seen lying free or within monocytic cells. In histological sections the picture was one of pneumonia, varying in degree but often very intense. This was both interstitial, with an accumulation of fluid and cells in the walls of the alveoli, and lobular with filling of the alveoli with fluid, monocytes and neutrophils.