Published online by Cambridge University Press: 11 May 2009
Phagocytes of the starfishes Asterias rubens L., and Marthasterias ghcialis (L.) (Echinodermata: Asteroidea) phagocytose allogeneic and xenogeneic phagocytes in vivo, but form non-reactive aggregates or syncytia in vitro. The coelomocytes of the sea urchins Echinus esculentus (Mortensen) and Psammechimts miliaris (Gmelin), (Echinodermata: Echinoidea) also form aggregates or syncytia with allogeneic and xenogeneic cells in vitro. Mutual cy totoxicity could not be demonstrated either by enzyme-release or by decrease in numbers of viable cells in cultures of mixed origin as compared with autogeneic controls. The factors which may govern cell recognition and behaviour are discussed.