Author/Authors :
FARAHMAND, Mahin Dept. of Parasitology - Pasteur Institute of Iran, Tehran, Iran , NAHREVANIAN, Hossein Dept. of Parasitology - Pasteur Institute of Iran, Tehran, Iran , KHALAJ, Vahid Dept. of Biotechnology - Pasteur Institute of Iran, Tehran, Iran , MOHEBALI, Mehdi Dept. of Medical Parasitology and Mycology - School of Public Health - Tehran University of Medical Sciences, Tehran, Iran , BARATI, Mohammad Dept. of Medical Parasitology and Mycology - School of Public Health - Tehran University of Medical Sciences, Tehran, Iran , NADERI, Sanaz Islamic Azad University, Science and Research Branch of Kurdistan, Sanandaj, Iran , Zabih ZAREI Meshkin-Shahr Research Station - School of Public Health - Tehran University of Medical Sciences, Meshkin-Shahr, Iran , KHALILI, Ghader Dept. of Immunology - Pasteur Institute of Iran, Tehran, Iran
Abstract :
Background: This study aimed to set-up latex agglutination test (LAT) and ELISA based
on recombinant A2 from Iranian strain of Leishmania (L.) infantum (rA2-Ag) and evaluated
for detection of anti- Leishmania antibodies in dogs compared to standard direct agglutination
test (DAT).
Methods: The rA2-Ag was synthesized under a part of the A2 gene sequences which contain
immune dominant sequences and less number of repetitive sequences. Latex beads, 0.8
μm (Sigma, USA) were sensitized with rA2-Ag. The tests were carried out on sera collected
from 350 ownership dogs including symptomatic (n=67), asymptomatic (n=230) canine
visceral leishmaniasis (CVL), and (n=53) uninfected domestic dogs as control group.
Results: Anti-leishmanial antibodies were detected in 97 (27.7%), 96 (27.4%) and 29 (%9)
of the serum samples by using DAT, rA2-ELISA, and rA2-latex, respectively with ≥1:320
as a cut-off titer when DAT-confirmed cases were compared with the control groups. A
combined sensitivity of 52% and specificity of 82.40% for rA2-ELISA and 23.8% and specificity
95.38%, respectively were found with ≥1:320 as a cut-off titer when DAT-confirmed
cases were compared with the control groups. The concordance between rA2-ELISA and
rA2 latex compared with DAT as a gold standard serological test for VL were found 73.7%
and 77.5%, respectively.
Conclusion: A good degree of agreement was found between rA2-ELISA and DAT
(73.7%). rA2-ELISA could detect more seropositive serum samples than rA2-LAT and it
may be recommended as an alternative tool for the diagnosis of CVL.
Keywords :
Recombinant A2 , Latex agglutination test , Canine visceral leishmaniasis , ELISA , Direct agglutination test , Iran
