The pig heavy and light chain immunoglobulin repertoires provide insights into the adaptive immune response against porcine reproductive and respiratory syndrome virus (PRRSV). (160.4)

Abstract

Abstract Antibody responses are critical to effective immunity to viral infections. Thus, extensive efforts have been directed to characterize antibody responses, including neutralizing antibodies, to PRRSV infection, in the expectation of elucidating key insights into protective and cross-protective immunity. Despite these efforts, the role of antibody responses in PRRSV immune protection remains poorly understood due, in part, to the lack of specific information about porcine immunoglobulin structures. To address this limitation, we characterized the expressed heavy and light chain immunoglobulin repertoires in healthy and PRRSV-infected pigs using amplicon-based 454 high-throughput sequencing. Bioinformatic analysis of approximately 450,000 heavy chain reads revealed differential heavy chain variable gene (IGHV) usage specific to PRRSV infection, including several exceptionally common immunoglobulin sequences representing clonally expanded B cell populations. The total richness of the heavy chain repertoire was approximately 3.5x105, equivalent to that reported in humans, suggesting that the swine antigen-binding repertoire is similarly complex, despite lack of diversity in the porcine IGHV framework regions. Initial analysis of over 13,000 light chain reads confirms that pigs use only two lambda J-C cassettes and are heavily reliant on a single kappa J gene. Further analysis of the light chain repertoire and its response to PRRSV infection is pending.