| Popis: |
Exoerythrocytic stages of Plasmodium gallinaceum and P. fallax from infected chick embryos were placed in chambers made of lucite rings and porous membranes which were inserted intraperitoneally into birds and mice, respectively. The chambers containing P. gallinaceum were made of membranes with pores of 0.45 ± 0.02 μ. Those placed into chickens were allowed to remain from 1 to 14 days then removed. Infections resulted in 11 of 66 chickens which served as recipients of the chambers. Similar chambers were also placed in turkeys and ducks. In the former nine of 11 turkeys either became infected or were proved to have latent infections by subinoculations into chicks, whereas no infections resulted in seven ducks in which the chambers were allowed to remain from 2–14 days. The ability of the parasites (probably the merozoites) to penetrate membranes with pore size of 0.45 ± 0.02 μ is clearly proved by these experiments. Greater foreign-body response around the chambers was observed on the part of chickens than of turkeys. Twenty chambers of the preceding type were placed in chick embryos. In two of these—removed on the 2nd and 5th days—parasites were observed microscopically, the latter one being more heavily infected than any tissue yet observed. The chambers containing chick embryo cells infected with P. fallax were placed into mice and allowed to remain for 3 days to 3 weeks. Membranes of three different pore-sizes were used — HA similar to those used in the experiments with P. gallinaceum , PH (pore-size: 0.3 ± 0.02 μ) and VM (pore-size: 50 ± 3 mμ). At 3-, 7-, 14-, and 21-day intervals the chambers were removed and the contents were subinoculated into turkey poults. The parasites in six of 20 chambers were shown to be viable by these subinoculations—three after 7 days, two after 14 days, and one after 21 days. No infections were observed in the mice. No evidence of survival of the parasites of P. fallax was obtained in a parallel series in which exoerythrocytic stages of this parasite were inoculated directly into mice. These experiments give evidence that the use of porous chambers has promising possibilities for the study of many problems in parasitology. |
