J Clin Pathol Qual Control.  1998 Jun;20(1):301-307.

Development Enzyme Immunoassay for the Quantitative Determination of Carcinoembryonic Antigen (CEA)

• Lee KO
• Kim KI
• Lee KP

Abstract

BACKGROUND: Carcinoembryonic antigen (CEA) has most widely been used for screening of gastrointestinal tumor in serum. The aim of this study is to develop simple enzyme immunoassay for the detection of CEA in serum.
METHODS
Polyclonal anti-CEA antibodies coated on the microtitration wells and monoclonal anti-CEA HRP for quantification was used to gain higher test sensitivity. Fifty microliter of anti-CEA-HRP conjugate was directly added to each well of specimen, standard and controls and incubated for 1 hour. After washing, the color reaction was developed for 10 minutes using chromogenic hydrogen peroxide/tetramethyl benzidine substrate system.
RESULTS
The correlation coefficient of CEA assay with standard materials was 0.9954 (slope=0.986, y intercept=1.654) and this system was linear between concentration of 1 ng/mL and 100 ng/mL of CEA. The within-day and between-day precision (%CV) in the high and low concentration ranges were below 7%. The correlation coefficient (r) between in -house CEA assay and commercial assay kit was 0.9959 (slope=1.3049, y intercept=1.0156). The fitted linear regressions in three patient samples for lineality test were over 0.995. The recovery tests were averaged 99.1%. With this method, serum CEA was determined in 100 healthy Koreans and 48 patients with gastric cancer. The results were 2.24+/-0.98 and an 31.2+/-46.5 mg/mL (Mean+/-SD) in normal control group and patient group, respectively.
CONCLUSIONS
The present method is simple and rapid, and has a high sensitivity. It can be useful for the prognosis after therapy as well as for screening of gastrointestinal tumor.

MeSH Terms

Antibodies
Carcinoembryonic Antigen*
Humans
Hydrogen
Immunoenzyme Techniques*
Linear Models
Mass Screening
Prognosis
Stomach Neoplasms
Antibodies
Carcinoembryonic Antigen
Hydrogen