1. A simple method is described for the formation of large numbers of lupus cells by positioning one drop of finger or ear blood of a lupus patient upon an accumulation of dried, normal polynuclear leukocytes. Thick leukemic smears and perhaps even imprints of various carcinomas or Hodgkin’s tissue can also be used as substrates.
2. No false positive results were obtained in a group of control patients.
3. Striking results were obtained with this method itt 20 of 21 known cases of disseminated lupus erythematosus. The remaining case in whom a single "L.E." cell was found by a conventional method, to date has yielded no lupus cells by our method.
4. The difference in appearance of the inclusion body of some of these cells from the characteristic Hargraves cell is highlighted.
5. Theoretic considerations of the mechanism of lupus cell formation are discussed and reassessed in the light of our experience with this method. For the formation of "L.E." cells it seems necessary that living polynuclear leukocytes, dead cells and lupus serum be brought together. The lupus serum can depolymerize the desoxyribose nucleic acid of the nuclei of the dead cells, but not of living cells. The depolymerized material is then phagocytized by living polynuclear cells and formation of lupus cells results.