Molecular Responses to Avian Reovirus Inoculation In Vitro.

Area of Science:

• Poultry Virology
• Transcriptomics
• Immunology

Background:

• Avian reovirus (ARV) is a significant poultry pathogen.
• Molecular responses to ARV infection across different cell types are not well understood.

Purpose of the Study:

• To investigate the differential transcriptomic responses to ARV S1133 infection in chicken embryo kidney (CEK), chicken embryo liver (CELi), and macrophage-derived (HD11) cells.
• To analyze viral replication rates and host transcriptional activity at various time points post-inoculation.

Main Methods:

• Transcriptomic analysis of CEK, CELi, and HD11 cells infected with ARV S1133 at 6, 12, and 24 hours post-inoculation.
• Differential gene expression analysis and protein-protein interaction (PPI) network construction.
• Assessment of viral replication titers and alternative splicing events.

Main Results:

• CELi cells showed the highest viral replication, while HD11 cells exhibited extensive transcriptional activity with limited viral load.
• HD11 cells displayed the most pronounced transcriptional changes, indicating a strong host response.
• CEK cells uniquely activated immune pathways like lymphocyte chemotaxis and type II interferon response.
• CELi cells upregulated antiviral defense genes, and significant alternative splicing was observed in immune-related transcripts.
• Key antiviral genes (IFI6, OASL, RSAD2, SAMD9L, MX1) were identified as central nodes in PPI networks.

Conclusions:

• ARV infection elicits cell-type and time-dependent viral replication and transcriptional responses in poultry.
• Distinct but interconnected immune pathways are activated across different cell types.
• Transcriptional activity, particularly in macrophages, is a critical component of the host response to ARV, even with low viral loads.