Detection of common antigens in primary and recurrent human meningiomas by radioimmunoassays and other serologic tests.

Antibodies in sera from 72 patients with untreated intracranial tumors, 60 patients with non-neural untreated tumors, and 30 normal donors were measured by immunodiffusion (ID), complement-fixation (CF), double-antibody precipitation radioimmunoassay (DAPRIA), and solid-phase bead-type radioimmunoassay (SBRIA) techniques using partially purified preparations of a reference meningioma-associated antigen (MAA), newly prepared MAAs derived from primary and recurrent tumors, and antigens from normal neural tissues. SBRIA tests were markedly more specific and sensitive than ID, CF, or DAPRIA in detecting MAA antibody. SBRIA tests also detected antibody reactive with common MAAs derived from primary and recurrent meningiomas in sera from meningioma patients prior to and following tumor excision. Checkerboard-type tests using dilutions of MAA versus sera from 20 meningioma patients and 20 age- (+/- 5 years) and sex-matched normal donors showed that antibody responses by the meningioma patients to MAA could be separated from those to other broad-reacting tumor and normal cell antigens, and from those of the matched normal donors. Sera from meningioma patients contained antibodies reactive with normal fetal, but not adult, neural antigens; thus suggesting a need for careful definition of control normal antigens used in serological testing.