Particulate Component of Plasma from Fowls with Avian Erythro-Myeloblastic Leucosis.

Abstract
A particulate material has been isolated by ultracentrifugal procedures from the filtered plasma of chickens diseased with avian erythro-myeloblastic leucosis. The particles were either spheroid in shape and of size varying from 60 to 100 m[mu] diam. or tailed structures with spheroidal heads and tails of 100 to 200 m[mu] lengths. Preliminary studies on small amts. of material yielded sedimentation diagrams showing definite, though diffuse, boundaries and an approximate sedimentation rate of 630 S. The ratio of N to desoxyribonucleic acid of the concentrates indicated a low content of the latter. Material of this sort was not found in the plasma of either normal chicks or chicks refractory to infection with the blood or plasma from birds with avian leucosis. The significance of the component in relation to the etiological agent of avian leucosis is discussed.