"Contact Reactions" Between Xenogeneic or Allogeneic Coelomic Cells of Solitary Ascidians

Abstract

The ability to distinguish self and nonself components seems to be widespread throughout the animal kingdom (Hildemann and Reddy, 1973; Cooper, 1976). The vertebrates, from the cyclostomes onward, are capable of mounting specific humoral as well as cell-mediated immune responses in defence against invading nonself components. In invertebrates, however, it is only in advanced organisms that recognition of foreignness is followed by selective destruction or elimination of such material, and even then this is accomplished only by means of cell-mediated mechanisms. It is as yet unclear whether invertebrates possess an ability for Fuke, Masako T. 1980. ""CONTACT REACTIONS" BETWEEN XENOGENEIC OR ALLOGENEIC COELOMIC CELLS OF SOLITARY ASCIDIANS." The Biological bulletin 158, 304-315.

Study of Color Variation in the Solitary Ascidian Halocynthia roretzi, Collected in the Inland Sea of Japan

“…According to previous studies (Fuke, 1980;Fuke and Nakamura, 1985;Sawada and Ohtake, 1994;Akita and Hoshi, 1995), the alloreactivity of H. roretzi hemocytes may be determined by genetics. In the solitary ascidians, these alloreactivity among allogeneic hemocytes are observed only in Halocynthia roretzi.…”

“…Alloreactivity of hemocytes is the distinct one which is thought to reflect genetic diversity in this species. Fuke (1980) found an allogeneic cytotoxicity "contact reaction" in the hemocytes of H. roretzi. This cytotoxic reaction is indicative of somatic cellular self-nonself recognition occurring in this species, which also shows this recognition in its germ cells via self sterility.…”

Xenogeneic Rejection among Three Botryllids (Compound Ascidians)

“…When coelomic cells from a solitary ascidian are mixed in vitro with coelomic cells from a different species or from another individual of the same species, cell lysis is caused by direct contact between hostand donor-derived cells (Fuke, 1980). This observation clearly shows that coelomic cells of these solitary ascidians have the recognition sites of self-nonself on their surfaces.…”

Opsonin-independent and -dependent Phagocytosis in the Ascidian Halocynthia roretzi: Galactose-specific Lectin and Complement C3 Function as Target-dependent Opsonins

“…We have been investigating defense cellular reactions, including phagocytosis, in a solitary ascidian, H. roretzi, which occupies a phylogenetical position between vertebrates and invertebrates (Azumi and Yokosawa, 1996). H. roretzi hemocytes undergo various defense reactions, such as phagocytosis (Ohtake et al, 1994), hemocyte aggregation (Takahashi et al, 1994), and a self and non-self recognition reaction (Fuke, 1980).…”