Development and Preliminary Application of a Colloidal-Gold Dual
Immunochromatography Strip for Detecting African Swine Fever Virus
Antibodies
Abstract
African swine fever (ASF) is an acute and highly contagious infectious
disease caused by the African swine fever virus (ASFV). Currently, there
is no vaccine against ASF worldwide, and no effective treatment measures
are available. For this reason, developing a simple, rapid, specific,
and sensitive serological detection method for ASFV antibodies is
crucial for the prevention and control of ASF. In this study, a 1:1
mixture of gold-labeled p30 and p72 probes was used as the gold-labeled
antigen. The p30 and p72 proteins and their monoclonal antibodies were
coated on a nitrocellulose membrane (NC) as a test (T) line and control
(C) line, respectively. A colloidal-gold dual immunochromatography strip
(ICS) for ASFV p30 and p72 protein antibodies was established. The
results showed that the colloidal-gold dual ICS could specifically
detect ASFV antibodies within 5–10 min. There was no cross-reaction
after testing healthy pig serum, porcine reproductive and respiratory
syndrome virus (PRRSV), foot-and-mouth disease type A virus (FMDV-A),
foot-and-mouth disease type O virus (FMDV-O), porcine circovirus type 2
(PCV-2), and swine fever (CSFV) positive sera. A positive result was
obtained only for the positive control, P1. The sensitivity of the test
strips was 1:256, which was equivalent to that of commercially available
ELISA kits. Their coincidence rate with the two commercial ASFV ELISA
antibody detection kits was higher than 98%. The test strips were
stably stored at 18–25 °C and 4 °C for 4 and 6 months, respectively.
The dual test strips prepared in this study had high sensitivity and
specificity and were characterized by rapid detection, simple operation,
and easy interpretation of results. Therefore, they are of great
significance to diagnose, prevent, and control African swine fever.