Immunoglobulin IgG Abnormalities and the Oligoclonal Pattern of IgG in Multiple Sclerosis Brains

Abstract

Elevated IgG distributed in oligoclonal bands is often observed in the CSF of MS patients. There is evidence that the abnormal IgG in CSF of MS patients is derived from intrathecal IgG production. Already in 1967 Tourtellotte et al. reported elevated IgG concentrations in both plaques and apparently normal white and grey matter of MS brains. Other studies in MS brains have confirmed the existence of elevated unbound IgG in plaque and non-plaque material (Link, 1972; Gilden et al., 1977; Mehta et al., 1981). Furthermore cell surface-bound IgG can also be eluted from MS brains with help of acid or alkaline extraction of brain material (Gilden et al., 1979; Mehta et al., 1981). Isoelectrofocussing (IEF) in combination with IgG immunofixation (IF) of MS brain extracts has frequently revealed an oligoclonal pattern of IgG (Link, 1972; Mattson et al., 1980; Mehta et al., 1981).