[Increased immune reactivity of exacerbated visceral lupus erythematosus: II. Reason and pathogenetic significance].

The sera of patients suffering from acute phase Lupus erythematosus visceralis contains factors inducing an increased blastoid transformation of lymphocytes: 1. one or some factors having a molecular weight ranging from 7.8 X 10(5) to 1.5 X 10(6) daltons. This active principle was shown to increase specifically the transformation of only the autologous lymphocytes. These high-molecular weights components are supposed to be antigen-antibody-complexes. 2. Beside those high-molecular weight components also low-molecular weight factors could be shown to increase the transformation of lymphocytes as well. By contrast these latter factors stimulate the transformation of autologous as well as homologous lymphocytes. The low-molecular weights components are stable after an incubation for 30 min after 56 degrees C and have molecular weights of about 7.5 X 10(4) and 1.6 X 10(5) daltons, respectively. Supposed the low molecular weight factors of the sera of exacerbated Lupus erythematosus visceralis are mitogenic lymphokines the increased activity of those mediators should possess pathogenic significance.