The use of ELISA, nPCR and qPCR for diagnosis of ocular toxoplasmosis in experimentally infected pigs. (December 2017)

• Record Type: Journal Article
• Authors: Garcia, João Luis; Burrells, Alison; Bartley, Paul M.; Bartley, Kathryn; Innes, Elisabeth A.; Katzer, Frank
• Is Part Of: Research in veterinary science. Volume 115(2017)
• Page Start: 490
• Page End: 495
• Publication Date: 2017-12
• Subjects: Toxoplasma gondii -- Retina -- Choroid -- Animals -- Ocular toxoplasmosis; Veterinary medicine -- Periodicals; Veterinary Medicine -- Periodicals; Médecine vétérinaire -- Périodiques; Médecine vétérinaire -- Recherche -- Périodiques; Diergeneeskunde; 636.089
• DOI: 10.1016/j.rvsc.2017.07.022
• Languages: English
• ISSNs: 0034-5288

Abstract

Abstract: In the present study we experimentally infected pigs with T. gondii tachyzoites, bradyzoites and oocysts in order to evaluate IgG-ELISA, nested-PCR, and qPCR for diagnosis of ocular infection. Eighteen pigs were divided into four groups: G1 (infected with 10 3 tissue cysts of the M4 strain (type II) at day 28, n = 5), G2 (infected with 10 3 oocysts of the M4 strain at day 28, n = 5), G3 (infected with tachyzoites of S48 strain (type 1) at day 0, n = 5), and G4 (uninfected unchallenged, control group n = 3). At day 70 of the experiment all animals were culled, and serum, aqueous humor (AH) and vitreous humor (VH) samples were collected to perform indirect ELISA, and PCR (nPCR, and qPCR). By ELISA nine pigs (60%) out of 15 were positive in VH samples, and seven out of 15 (46%) were positive in AH samples. Both molecular techniques used here, nPCR and qPCR, were able to detect < 50 fg of T. gondii tachyzoite DNA. The nPCR and qPCR detected six (7/15, 47%) and two (2/15, 13.3%) positive animals respectively. Antibody responses were detected in serum and in AH and VH from the eye, suggesting that pigs may be an animal that could be used as a model to further our understanding of diagnosis of human ocular infection with T. gondii . Highlights: Pigs should be tested more as a model for ocular T. gondii infection. The combination of serological and PCRs based assays should be used to improve the diagnosis of ocular T. gondii infection nPCR (ITS1) and qPCR (529 bp) were able to detect < 50 fg of T. gondii tachyzoite DNA.