Hemocyte morphology and phagocytic activity in the common cuttlefish (Sepia officinalis)

Fish Shellfish Immunol. 2014 Oct;40(2):362-73. doi: 10.1016/j.fsi.2014.07.020. Epub 2014 Jul 25.


Little is known about the immune system of cephalopods, in spite of their many highly derived characters within the molluscan clade, including a vertebrate-like high-pressure closed circulatory system. Further the economic importance of cephalopod fisheries, potential for aquaculture, and use as ecotoxicology models demand a thorough understanding of their immune system. In this study, we present a comprehensive characterization of hemocytes in the common cuttlefish Sepia officinalis. Cytological stainings, electron microscopy- and flow cytometry-observations highlight a single granulocyte population with various densities of eosinophilic granules and unstained vesicles. These hemocytes contain acid phosphatase-, lysozyme- and proPO system enzymes, and have high activity in bead phagocytosis assays. Interestingly, bead pre-incubation in plasma results in time-dependent aggregation perhaps resulting from hemocyanin-coating, and decrease in phagocytosis. This study provides the basis for understanding hemocyte-mediated immunity in the common cuttlefish, and essential background for future studies on cephalopod immunity.

Keywords: Cephalopod mollusks; Cuttlefish (Sepia officinalis); Enzymatic assay; Hemocyte population; Phagocytosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Flow Cytometry
  • Hemocytes / cytology*
  • Microscopy, Electron, Scanning
  • Microscopy, Electron, Transmission
  • Phagocytosis*
  • Sepia / immunology*