Hemocytes of the carpet shell clam (Ruditapes decussatus) and the Manila clam (Ruditapes philippinarum): Current knowledge and future prospects

Abstract

: Hemocytes are the immune effectors in clams, directing cellular but also humoral defences. In the Manila clam (Ruditapes philippinarum) and the carpet shell clam (Ruditapes decussatus), two phenotypically similar venerid species, fishery and aquaculture importance motivated scientific studies to improve knowledge about the participation of hemocytes in immune response. Currently, gaps still persist concerning the classification of hemocyte sub-populations as well as their non-immune activities. This review summarizes current knowledge about hemocytes of the Manila clam and the carpet shell clam, suggests some probable misinterpretations arising from extrapolations from other bivalves and vertebrates, and suggests future research prospects. The susceptibility of hemocytes to environmental modifications as well as biological and chemical toxicants is also re-evaluated. Hemocytes of bivalves are not limited in function to immunity and should be considered in a wider scheme including the environment and whole-animal physiology.

Age-dependent expression of stress and antimicrobial genes in the hemocytes and siphon tissue of the Antarctic bivalve, Laternula elliptica, exposed to injury and starvation

“…Cellular reactions include phagocytosis and the generation of reactive oxygen species (ROS) ("oxidative burst"). These are mediated by the hemocytes (Donaghy et al 2009;Husmann et al 2011;Pruzzo et al 2005). These cells have key functions not only in immunity but also in the maintenance of physiological homeostasis.…”

“…These cells have key functions not only in immunity but also in the maintenance of physiological homeostasis. They are involved in the inflammatory response, wound repair, shell formation, transport of nutrients, digestion, as well as excretion of biological active molecules such as enzymes or antimicrobial peptides (Canesi et al 2002;Donaghy et al 2009;Kadar 2008). In order to regenerate integrity and function in organs after injury, hemocytes migrate towards the wound and infiltrate the affected tissue (de Eguileor et al 1999;Ottaviani et al 2010).…”

Characterisation of Duplicated Haemoglobin Genes in Bivalves

“…Bivalve molluscs of the family Arcidae includea number of major fishery and aquaculture species such as T. granosa, S. inaequivalis, S. broughtonii and A. trapezia (Donaghy et al, 2009;Bao et al, 2013b). Besides their importance as food sources, bivalve molluscs are frequently used as indicators of pollution and overall health of ecosystems.…”

“…Of these, a well-known example is that of a neofunctionalised copy of an elastin gene which contributed to the evolution of the bulbus arteriosus, a novel organ found in the heart of teleost fish (Moriyama et al, 2016 (Bao et al, 2013b;Vinogradov & Moens, 2008;Weatherall, 2001;Donaghy, 2009). For example, a duplicated gene encoding a dimeric Hb from the arcid bivalve T.…”

The Effects of 4-Nonylphenol on the Immune Response of The Pacific Oyster, Crassostrea Gigas, Following Bacterial Infection (Vibrio Campbellii)

“…Secretion of these soluble defense factors by hemocytes plays an important role in the immunity of most invertebrates (Donaghy et al, 2009). The fluid hemolymph of most bivalves contains proteins including antimicrobial peptides, soluble lectins, lysins, agglutinins, and lysosomal enzymes (Pruzzo et al, 2005).…”