CNS tumours: oligoclonal immunoglobulin D in cerebrospinal fluid and serum

Oligoclonal immunoglobulin D bands were detected by isoelectric focusing in 7 out of 25 unconcentrated cerebrospinal fluid (CSF) samples obtained from patients with tumours of the central nervous system (CNS). The tumours wer e confirmed by clinical and histological findings. Two patients with CNS ma lignancy had intrathecal synthesis of oligoclonal bands both IgD and IgG. F our patients with a variety of CNS tumours had a systemic IgD immune respon se but no oligoclonal IgG bands. One patient with the most malignant tumour histology had a systemic IgD response as well as local synthesis of IgG. T he study reveals several new aspects regarding CNS tumours: they are immuno logically active and are capable of invoking oligoclonal immunoglobulin pro duction both within the CNS and systemically. Multiple immunoglobulin activ ation can be found in malignant CNS tumours, and systemic IgD production ma y occur independently from IgG synthesis and may represent an immune respon se to a neoantigen produced in the CNS compartment.