Distribution of measles antigen and immunoglobulin-containing cells in the CNS in subacute sclerosing panencephalitis (SSPE) and atypical measles encephalitis.

The immunoperoxidase technique has been used to study the distribution of measles virus antigen and immunoglobulin (Ig)-containing cells within the CNS, in 5 cases of subacute sclerosing panencephalitis (SSPE) and 1 case of atypical measles encephalitis. Measles virus antigen was demonstrated within the brain in all cases, and in the spinal cord in 1 case of SSPE. Ig-containing cells were also demonstrated in all cases, the proportions of the different light and heavy chain types varying somewhat from case to case. In SSPE IgG constituted the major and IgA the principal minor heavy chain demonstrated. In all cases of SSPE there was significant excess of light-chain-containing over heavy-chain-containing cells. In the case of atypical measles encephalitis there was a paucity of Ig-containing cells and a relatively high proportion (39%) of these contained IgM. The case of atypical measles encephalitis differed from those of SSPE also in the presence of multinucleate giant cells, some of which contained measles virus antigen.