Many authors have suggested that collagen diseases are manifestations of an allergic reaction. Dr. Criep1 has discussed the role of allergic phenomena in the so-called collagen diseases. Dr. Rich2 produced experimental periarteritis nodosa by sensitization with sulfonamides and horse serum.
One of the manifestations of the collagen diseases is the lupus erythematosus (LE) cell phenomenon based on the presence of an antinuclear antibody. The LE phenomenon consists of phagocytosis of nuclear material by polymorphonuclear leukocytes and is found in smears of bone marrow from patients or produced in vitro by incubating sera of patients with the buffy coat of normal blood. The LE factor responsible for the nucleophagocytosis is a 7S gamma globulin and it has properties of an antibody against cell nuclei or, more specifically, against nucleoproteins. The sera of some patients suffering from disseminated lupus erythematosus contain antibodies against desoxyribonucleic acid (DNA) detectable in precipitation and