Single-cell transcriptome analysis reveals a cellular immune response in freshwater dark sleeper (Odontobutis potamophila) after infection with Aeromonas veronii

Abstract

The bacterium Aeromonas veronii is a co-pathogenic species that can negatively impact the health of both humans and aquatic animals. In this study, we used single-cell transcriptome analysis (scRNA-seq) to investigate the effects of infection with A. veronii on head kidney cells and the regulation of gene expression in the dark sleeper (Odontobutis potamophila). scRNA-seq was used to assess the effects of infection with A. veronii in O. potamophila B cells, endothelial cells, macrophages, and granulocytes, and differential enrichment analysis of gene expression in B cells and granulocytes was performed. The analyses revealed a significant increase in neutrophils and decrease in eosinophils in granulocytes infected with A. veronii. Activation of neutrophils enhanced ribosome biogenesis by up-regulating the expression of RPS12 and RPL12 to fight against invading pathogens. Crucial pro-inflammatory mediators IL1B, IGHV1-4, and the major histocompatibility class II genes MHC2A and MHC2DAB, which are involved in virulence processes, were upregulated, suggesting that A. veronii activates an immune response that presents antigens and activates immunoglobulin receptors in B cells. These cellular immune responses triggered by infection with A. veronii enriched the available scRNA-seq data for teleosts, and these results are important for understanding the evolution of cellular immune defense and functional differentiation of head kidney cells.

Fishing Innate Immune System Properties through the Transcriptomic Single-Cell Data of Teleostei

“…The sequencing of head kidney cells for dark sleeper, Odontobutis potamophila, in response to Aeromonas veronii [137] (GSE229275) showed a significant increase in neutrophils and a decrease in eosinophils in infected granulocytes, as well as the enhancement of ribosome biogenesis through upregulation of RPS12 and RPL12 and upregulation of the key proinflammatory mediators IL1B and IGHV1-4 and the major histocompatibility class II genes MHC2A and MHC2DAB. The treatment of Aeromonas veronii could be used as a model to study mechanisms of such human diseases as bacteremia, gastroenteritis, and softtissue infections [138].…”

Proteomics-Based Investigation of Different Live Prey Administered to Freshwater Dark Sleeper (Odontobutis potamophila): Examining the Effects on Glycolipids and Energy Metabolism

“…The freshwater dark sleeper (Odontobutis potamophila) is a well-known economic freshwater fish with a unique diet and lifelong feeding on live prey [17]. Currently, the most commonly used live prey in production are Cladocera, Tubifex, and silver carp fry.…”