Acta Tropica 75 (2000) 9–17 Immunodiagnosis of human eosinophilic meningitis using an antigen of Angiostrongylus cantonensis L 5 with molecular weight 204 kD Soi-Moi Chye a , Jui-Hsien Chang b , Chuan-Min Yen c, * a Fooyin Institute of Technology, Kaohsiung County, Taiwan, ROC b Department of Parasitology, National Cheng Kung Uniersity Medical College, Tainan, Taiwan, ROC c Department of Parasitology, Kaohsiung Medical College, No. 100, Shih -Chuan 1st Road, Kaohsiung, Taiwan, ROC Received 1 October 1998; received in revised form 16 September 1999; accepted 11 October 1999 Abstract An antigen from Angiostrongylus cantonensis fifth-stage larvae was purified by immuno-affinity chromatography with a specific monoclonal antibody. The purified antigen showed only a single band with a molecular weight of 204 kD in SDS – PAGE, and no cross-reactivity to antibodies induced by several other species of helminths were observed in ELISA. When the purified antigen was used to examine serum and cerebrospinal fluid (CSF) specimens by ELISA, the antibody levels in patients with eosinophilic meningitis or meningoencephalitis (EME) were significantly higher than those of control subjects. The antibody levels in serum were slightly higher than those in CSF, and the levels in serum were positively correlated with the levels in CSF. The reliability in detection of antibodies in serum was slightly higher than that in the detection of antibodies in CSF specimens. The purification of a specific A. cantonensis antigen and its subsequent use in the development of an ELISA for detection of A. cantonensis specific antibodies in serum specimens constitute an important step towards improvement in the accuracy of diagnosis for A. cantonensis infections. © 2000 Elsevier Science B.V. All rights reserved. Keywords: Angiostrongylus cantonensis ; mAbs purified antigen; ELISA; Eosinophilic meningitis www.elsevier.com/locate/actatropica 1. Introduction Angiostrongylus cantonensis, a widespread ne- matode in southeast Asia and the Pacific islands, is believed to be the main pathogen resulting in human eosinophilic meningitis or meningoen- cephalitis (EME). It is one of the many clinically significant zoonotic parasites in Taiwan. To date, this parasite has been identified throughout the island of Taiwan, and several hundred human cases of central nervous system disease caused by this parasite have been reported by Cheng et al. (1984). In humans, the ingested third-stage larvae * Corresponding author. Tel.: +886-7-3121101 ext. 2169; fax: +886-7-3218309. E-mail address: chmiye@cc.kmu.edu.tw (C.-M. Yen) 0001-706X/00/$ - see front matter © 2000 Elsevier Science B.V. All rights reserved. PII:S0001-706X(99)00082-0