Identification of the HA-2 agglutinin in the haemolymph of the ascidian Botrylloides leachii as the factor promoting adhesion of sheep erythrocytes to mouse macrophages

Evolutionary perspectives on amyloid and inflammatory features of Alzheimer disease

We propose that the amyloid deposits in senile plaques of Alzheimer's Disease (AD) result from ancient mechanisms in wound-healing and inflammatory processes that preceded the evolution of the inducible combinatorial immune responses characteristic of jawed vertebrates. AD plaques are unlike active plaques in MS, because antibodies, T-cells and, B cells are not conspicuous components of senile plaques or other loci of degeneration. However, senile plaques contain amyloids and other inflammatory proteins of ancient origin that appear to be made by local brain cells, including neurons, astrocytes, and microglia. We describe a highly conserved 16-mer found in pentrakins from mammals and from the horseshoe crab. The senile plaque thus provides a novel opportunity to study primitive features of complement-mediated inflammatory responses in the absence of immunoglobulins.

A humoral opsonin from the solitary urochordate Styela clava

Opsonins play a key role in invertebrate humoral immune systems. An opsonin for yeast was identified in the plasma of the tunicate, Styela clava. In vitro cultures of hemocytes with homologous plasma-incubated yeast exhibited significantly higher levels of phagocytosis than controls. Studies indicated that the opsonic activity of Styela clava plasma increased the overall capacity for phagocytosis. Opsonization was inhibited by the carbohydrates mannan, N-acetyl-D-galactosamine, and galactose, and by the divalent cation chelator, EDTA. These data suggest that the Styela clava opsonin may share some functional similarities with a C-type lectin. Incubation of yeast with Styela clava and Styela plicata plasma prior to phagocytosis by hemocytes from both species indicated the Styela clava opsonin is species specific.

Galactose-specific lectin in the hemolymph of solitary ascidian, Halocynthia roretzi. Molecular, binding and functional properties

Galactose-specific lectin isolated from the hemolymph of solitary ascidian, Halocynthia roretzi, has been further characterized. The hemagglutinating activity of the lectin is Ca2+-dependent. The lectin has a large molecular form as revealed by gel-permeation chromatography, sedimentation equilibrium and velocity measurement, and electron microscopic observation. The lectin is adsorbed to columns of blue-Sepharose and phenyl-Sepharose, and eluted with ethylene glycol, not with lactose or high concentration of NaCl. The lectin shows a stimulatory effect on the superoxide anion production by guinea-pig polymorphonuclear leukocytes, and the effect is inhibited, among various sugars, most strongly by melibiose.