Comparison of the immune response to vaccination with pigeon circovirus recombinant capsid protein (PiCV rCP) in pigeons uninfected and subclinically infected with PiCV

PLoS One. 2019 Jun 28;14(6):e0219175. doi: 10.1371/journal.pone.0219175. eCollection 2019.

Abstract

Infections with immunosuppressive pigeon circovirus (PiCV) pose the most severe health problem to the global pigeon breeding. The vaccination with immunogenic PiCV recombinant capsid protein (PiCV rCP) is a potential tool for disease control. Because of the high prevalence of PiCV asymptomatic infections, the subclinically infected pigeons will be vaccinated in practice. The aim of this study was to answer a question if vaccination of asymptomatic, infected with PiCV pigeons induces a similar immune response to PiCV rCP as in uninfected birds. One hundred and twenty 6-week-old carrier pigeons were divided into 4 groups (2 groups of naturally infected and uninfected with PiCV individuals). Birds from groups V and V1 were vaccinated twice with PiCV rCP mixed with an adjuvant, whereas pigeons from groups C and C1 were immunized with an adjuvant only. The expression of genes encoding IFN-γ, CD4, and CD8 T lymphocyte receptors; the number of anti-PiCV rCP IgY-secreting B cells (SBC) and anti-PiCV rCP IgY were evaluated 2, 21, 39 and 46 days post vaccination (dpv). Study results showed that the expression of CD8 and IFN-γ genes was higher in both groups of infected pigeons than in the uninfected birds, irrespective of vaccination. In the uninfected birds, the expression of these genes was insignificantly higher in the vaccinated pigeons. The anti-PiCV rCP IgY-SBC were detected on 2 and 23 dpv and seroconversion was noted on 23 and 39 dpv in V and V1 groups, respectively. In the light of the results obtained, it could be concluded that pigeon circovirus recombinant capsid protein elicits the immune response in both naturally infected and uninfected pigeons, but its rate varies depending on PiCV infectious status. The infection with PiCV masks the potential cellular immune response to the vaccination with PiCV rCP and leads to the suppression of humoral immunity.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Viral / metabolism
  • Bird Diseases / drug therapy*
  • Bird Diseases / immunology
  • CD8 Antigens / genetics
  • Capsid Proteins / administration & dosage*
  • Capsid Proteins / immunology
  • Circoviridae Infections / drug therapy
  • Circoviridae Infections / immunology
  • Circoviridae Infections / veterinary*
  • Circovirus / immunology
  • Circovirus / metabolism*
  • Columbidae
  • Interferon-gamma / genetics
  • Recombinant Proteins / administration & dosage
  • Recombinant Proteins / immunology
  • Treatment Outcome
  • Up-Regulation
  • Vaccination / veterinary
  • Viral Vaccines / administration & dosage*
  • Viral Vaccines / immunology

Substances

  • Antibodies, Viral
  • CD8 Antigens
  • Capsid Proteins
  • Recombinant Proteins
  • Viral Vaccines
  • Interferon-gamma

Grants and funding

This research was partially supported by the National Science Centre (Poland) as a grant No. 2014/15/D/NZ6/02416 (www.ncn.gov.pl) awarded to TS. Publication supported by KNOW (Leading National Research Centre) Scientific Consortium "Healthy Animal - Safe Food", decision of Ministry of Science and Higher Education No. 05- 1/KNOW2/2015. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.