Free light chains of immunoglobulins in the cerebrospinal fluid of human immunodeficiency virus type 1-infected patients

Abstract

The presence of immunoglobulin (Ig) free light chains (FLC) was investigated in the cerebrospinal fluid (CSF) of human immunodeficiency virus type 1 (HIV-1)-infected patients. Intrathecal synthesis of FLC was demonstrated in 80% of the patients, even in the absence of oligoclonal Ig. The FLC patterns were characterized by restricted heterogeneity with regard to both isoelectric point and the molecular weight, and were mainly composed by dimers rather than monomers. A striking prevalence of lambda FLC was also observed. Local production of FLC can be taken as a marker of an ongoing immunopathological process within the central nervous system (CNS) in HIV-1-infected patients. A deregulation of Ig production by intrathecally activated B cells may be hypothesized.