Biological characterisation of novel plasmid-carrying avian Chlamydia abortus strain 84/2334, a vaccine candidate for enzootic abortion in sheep

01 October 2023 → 30 September 2027
Regional and community funding: Special Research Fund
Research disciplines
  • Natural sciences
    • Infectious diseases
    • Epigenetics
    • Transcription and translation
sheep Biology Vaccination Zoonosis Ovine enzootic abortion (OEA) Chlamydia abortus
Project description

Chlamydia abortus infects sheep causing ovine enzootic abortion (OEA). The commercial inactivated vaccines have low efficacy and the live vaccines can cause OEA.

We isolated strain 84/2334 from a parrot and classified it initially as Chlamydia psittaci. However, in depth genomic analysis revelaed that the strain actually belongs to a new avian C. abortus genotype. Sheep C.abortus strains have no plasmid, but 84/2334 has a plasmid, just as in avian C. psittaci. 84/2334 can thus genetically be manipulated via its plasmid leading to a novel OEA vaccin. However, before creating mutant 84/2334, we do need to know if 84/2334 is biologically similar to 'sheep C. abortus', and thus suitable for vaccin engineering. For this we will: i) compare their infection dynamics (growth kinetics, live-cell imaging, electron microscopy), ii) their RNAseq profiles (pahogen and host cell) and iii) modulation of their host cell epigenome in vitro.