Vertical transmissibility of small ruminant lentivirus

PLoS One. 2020 Nov 18;15(11):e0239916. doi: 10.1371/journal.pone.0239916. eCollection 2020.

Abstract

This study aimed to evaluate by means of Nested Polymerase Chain Reaction (nPCR), co-cultivation and sequencing, with genetic comparison between strains (mother/newborn), the occurrence of vertical transmission of Small Ruminant Lentiviruses (SRLV) from naturally occurring nannies infected for their offspring. For the detection of SRLV seropositive progenitors, blood was collected from 42 nannies in the final third of gestation in tubes with and without anticoagulant. The diagnostic tests used were Western Blot (WB) and nPCR. During the period of birth, the same blood collection procedure was performed on 73 newborns at zero hours of birth, with the same diagnostic tests. Seventeen blood samples from seven-day-old kids, proven positive for SRLV by nPCR, chosen at random, were subjected to coculture in goat synovial membrane (GSM) cells for 105 days. The pro-viral DNA extracted from the cell supernatant from the coculture was subjected to nPCR. For DNA sequencing from the nPCR products, nine positive samples were chosen at random, four nannies with their respective offspring, also positive. Each sample was performed in triplicate, thus generating 27 nPCR products of which only 19 were suitable for analysis. Among the 42 pregnant goats, in 50% (21/42) pro-viral DNA was detected by nPCR, while in the WB, only 7.14% (3/42) presented antibodies against SRLV. Regarding neonates, of the 73 kids, 34 (46.57%) were positive for the virus, using the nPCR technique, while in the serological test (WB), three positive animals (4.10%) were observed. The coculture of the 17 samples with a positive result in the nPCR was confirmed in viral isolation by amplification of the SRLV pro-viral DNA. When aligned, the pro-viral DNA sequences (nannies and their respective offspring) presented homology in relation to the standard strain CAEV Co. It was concluded that the transmission of SRLV through intrauterine route was potentially the source of infection in the newborn goats.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Newborn / virology
  • Cell Line
  • DNA, Viral / blood
  • Female
  • Goat Diseases / transmission*
  • Goat Diseases / virology
  • Goats / virology
  • Infectious Disease Transmission, Vertical / veterinary*
  • Lentivirus / isolation & purification
  • Lentivirus Infections / transmission*
  • Lentivirus Infections / veterinary
  • Polymerase Chain Reaction
  • Pregnancy
  • Proviruses / genetics
  • Proviruses / isolation & purification*
  • Sequence Analysis, DNA
  • Sheep / virology
  • Sheep Diseases / transmission*
  • Sheep Diseases / virology

Substances

  • DNA, Viral

Grants and funding

This study was supported by the Cearense Foundation of Support for Scientific and Technological Development (FUNCAP) in the form of funding (project number BP3-0139-00328.01.00/2018) and scholarship awarded to JFA, the National Council for Scientific and Technological Development (CNPq) in the form of a scholarship awarded to RMP (project number 312900/2019-8), Embrapa Goats and Sheep in the form of a funding awarded to AA, RRP, LHS, ALMdS, DAAdA, and AMCL (project number SEG 02.13.10.003.00.00), and the Northeast Network in Biotechnology, State University of Ceará (RENORBIO/UECE) in the form of funding awarded to MFdST. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.