1. Isolated leukocyte nuclei quantitatively adsorb lupus factor from serum. In the presence of viable leukocytes such nuclei which have adsorbed the lupus factor become transformed into typical L.E. cells.
2. Leukocytes with an intact cytoplasm fail to adsorb L.E. factor.
3. These studies suggest that the living leukocytes, apart from simple phagocytosis, serve other functions in the L.E. phenomenon:
(a) the disruption of the integrity of the cytoplasmic envelope of dead leukocytes so as to allow for the adsorption of L.E. factor to the cell nucleus.
(b) the transformation of the nuclei, to which L.E. factor has been adsorbed, into swollen homogenous lupus bodies.