Preparation of antisera directed against the idiotype(s) of immunoglobulin G from the cerebrospinal fluid of patients with multiple sclerosis.

Abstract

Abstract Two antisera were raised against the idiotype(s) of the IgG from the cerebrospinal fluid (CSF) of two patients with multiple sclerosis (MS). We immunized guinea pigs with complexes formed by incubation of Sepharose-bound guinea pig anti-human IgG with CSF. The immunization procedure required a small amount of CSF (1 ml or less). Two radioimmunoassay procedures for the detection of idiotype(s)-positive IgG (neither of which required purified IgG) are described: 1) by means of Sepharose-bound CSF proteins (Seph-CSF), the response of the guinea pigs was measured before and after absorption of the antisera with pooled normal human serum (NHS); in this way, we screened antisera for antibodies directed against the idiotype(s) of CSF-IgG or a CSF-specific protein. 2) With the use of Sepharose-bound antiserum (previously absorbed with Sepharose-NHS), it is demonstrated that both antisera are reactive with IgG from the CSF and also with IgG from the serum of the corresponding patients. In the two patients under investigation, the ratio (concentration of idiotype(s)-positive IgG in the CSF) :(concentration of idiotype(s)-positive IgG in the serum) was 4 to 8 times as high as the ratio (concentration of total IgG in the CSF): (concentration of total IgG in the serum). No cross-reactions were found between both CSF with either of the antisera. Neither antiserum reacted with the Seph-CSF of 13 other MS patients, nor with the Seph-CSF of 28 patients with other neurologic diseases.