Biomphalaria glabrata amoebocytes: Effect of Schistosoma mansoni infection on in vitro phagocytosis

Ultrastructural study of the in vitro interaction between Biomphalaria glabrata hemocytes and Schistosoma mansoni miracidia

“…Morphological and ultrastructural methods previously employed for the characterization of vertebrate immune systems (macrophages, lymphocytes, and polymorphonuclears) under normal conditions and parasitic infections were used for identifying mollusc hemocytes (Sminia & Barendsen 1980, Ottaviani & Franchini 1988, Abdul-Salam & Michelson 1980, Barracco et al 1993. It has been lately suggested that some bacteria toxins are able to induce the re-arranging of Rho superfamily proteins and cytoskeleton alterations (stress fibers) in epithelial cells (Brest et al 2003).…”

“…B. glabrata hemocytes are capable of binding and destroying the parasite larvae by (1) phagocytosis of the tegument, (2) liberation of cytotoxic components or (3) both mechanisms simultaneously (Adema & Loker 1997, Hampton et al 1998. These defense mechanisms have been described for resistent molluscs whereas in susceptible molluscs, the hemocytes bind to the parasites in a transitory and inefficient way allowing the successful evolution of the parasite (Vasquez & Sullivan 2001 Morphological and ultrastructural methods previously employed for the characterization of vertebrate immune systems (macrophages, lymphocytes, and polymorphonuclears) under normal conditions and parasitic infections were used for identifying mollusc hemocytes (Sminia & Barendsen 1980, Ottaviani & Franchini 1988, Abdul-Salam & Michelson 1980, Barracco et al 1993. It has been lately suggested that some bacteria toxins are able to induce the re-arranging of Rho superfamily proteins and cytoskeleton alterations (stress fibers) in epithelial cells (Brest et al 2003).…”

A contribution to the pathobiology of Biomphalaria glabrata hemocytes

“…They are found in the circulating hemolymph and within the connective tissues, but the relationships between these two compartments are poorly understood. Abdul-Salam and Michelson (1980) observed an increase in the number of circulating hemocytes in B. glabrata after a 4 and 6-week S. mansoni infection. The same was also seen in B. glabrata during infection with Echinostoma liei (Mounkassa & Jourdane 1990).…”

Parasite-Invertebrate Host Immune Interactions

“…Using this approach, suppression of in vitro phagocytic activity has been observed in snails infected with schistosomes (e.g., Abdul-Salam and Michelson 1980;Van der Knaap et al 1987;Fryer and Bayne 1990;Amen et al 1991) and echinostomes (Noda and Loker 1989a), and insects infected with the acanthocephalans (Lackie and Holt 1988). In addition to phagocytic function, Lackie and Holt (1988) also reported a generalized suppression in host nodulation responses to injected yeast, /3-1,3 glucaninduced phenoloxidase activity, and melanization responses to concurrent larval cestode infection.…”