Open AccessPreparation and characterization of anti‐anti‐idiotypic monoclonal antibody (“Ab1‐like Ab3”) in relation to carcinoembryonic antigen
Author(s) -
Tsujisaki Masayuki,
Masuya Jiro,
Okada Yoshimasa,
Jinnohara Tsuneharu,
Sasaki Shigeru,
Yachi Akira,
Imai Kohzoh
Publication year - 2002
Publication title -
journal of clinical laboratory analysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.536
H-Index - 50
eISSN - 1098-2825
pISSN - 0887-8013
DOI - 10.1002/jcla.10058
Subject(s) - idiotopes , epitope , monoclonal antibody , polyclonal antibodies , idiotype , microbiology and biotechnology , antiserum , carcinoembryonic antigen , antigen , antibody , mimotope , chemistry , biology , immunology , cancer , genetics
In order to analyze the epitope structure of carcinoembryonic antigen (CEA) and the idiotype network system, seven anti‐idiotypic monoclonal antibodies (anti‐Id MoAbs) were generated from a BALB/c mouse immunized with anti‐CEA MoAb P1‐356, which recognized a synthetic peptide P1 of CEA, domain I. These MoAbs were divided into four groups. The anti‐Id MoAbs specifically reacted with MoAb P1‐356, but not with any MoAb, and inhibited the binding of MoAb P1‐356 to CEA, indicating that all of these anti‐Id MoAbs recognized private idiotopes at the combining sites of MoAb P1‐356. Polyclonal anti‐anti‐idiotypic antiserum (Ab3) generated with anti‐Id MoAbs M315 (Ab2), blocked the binding of MoAb P1‐356 (Ab1) to CEA and reacted with CEA(Ag) and synthetic peptide P1. The analysis of serological assays suggested that it contains “Ab1‐like Ab3.” Therefore, we prepared anti‐anti‐Id MoAbs using anti‐Id MoAb M315. Among 13 candidates, anti‐anti‐Id MoAb 11B2 was selected, because it competed with MoAb P1‐356 (Ab1) binding to CEA. A direct binding assay using MoAb11B2 showed that it reacted with purified CEA and with CEA synthetic peptide P1. In addition, MoAb 11B2 (Ab3) reacted with both CEA‐producing cultured cells and colonic cancerous tissues in immunostaining. These results indicate that anti‐anti‐Id MoAb 11B2 is “Ab1‐like Ab3.” Therefore, it is suggested that anti‐Id MoAb M315 bears an “internal image” of the MoAb P1‐356‐defined epitope on CEA. J. Clin. Lab. Anal. 16:279–289, 2002. © 2002 Wiley‐Liss, Inc.