A patient with SLE experienced an acute exacerbation of illness with continuous
daily fever of 40°C to 42°C for several weeks with
increased proteinuria (A). Sequential serum samples showed the
presence of autoantibody to DNA, which was replaced by circulating DNA antigen
during the disease flare. (B) Immunodiffusion studies demonstrating
that pre-flare serum samples from 2-14 and 2-19 contained antibody to DNA (i,
upper set of wells). In the lower set of wells, the central well was filled with
serum from 2-19 (ii, containing autoantibody to DNA). Precipitin reactions were
observed between this serum and those of 4-18 and 4-26. Chemical studies confirmed
the presence of DNA in the latter two samples. Absence of either antibody to DNA
or DNA antigen was observed at 3-26, a period of transition from antibody excess
to antigen excess. The time line in A shows a period of eight months
in the patient’s history and is not calendar time. Adapted from ref.
1.