Blood cells and pigments in the ascidians, Halocynthia roretzi and Halocynthia aurantium aurantium

Halocynthia roretzi and Halocynthia aurantium aurantium are both common solitary ascidians for foods in Japanand belong to same genus. H. roretzi shows allorecognition, allogeneic cytotoxic reaction (allogeneic contact reaction)between allogeneic blood cells. However, H. aurantium aurantium does not show allogeneic contact reaction. In this report,we compared blood cells and pigments between these two species. Under right-microscopic observations (including aphase-contrast microscopic and a differential interference contrast microscopic observations), blood cells of two specieswere almost same in morphology. In H. roretzi, two blood cell types, Granular cells type 3 (g3-cells=viriform cells) andVacuolated cells type 3 (v3-cells) had dopa-quinones and phenoloxidase (PO). In H. aurantium aurantium, three bloodcell types, Mature morula cells, Immature morula cells and Compartment cells had dopa-quinones and PO. By pigmentsextraction and thin-layer chromatography of two species, it was cleared that pigments of two species were almost same.Although H. roretzi and H. aurantium aurantium have almost same blood cells and pigments, in this report, it is notunderstand that only H. roretzi shows allogeneic contact reaction