Lectins and saccharides inLymnaea stagnalis haemocyte recognition |
| |
Authors: | P Horák and R Deme |
| |
Institution: | (1) Department of Parasitology, Charles University, Viničná 7, CZ-12844 Prague 2, Czech Republic |
| |
Abstract: | Lectins as important non-self-recognition factors are present on molluscan haemocytes as membrane receptors or in cell-free
plasma as soluble recognition factors. The recognition mediated by them can be operational in Ca2+-dependent and-independent ways.
In our phagocytosis system,Lymnaea stagnalis haemocytes and rabbit erythrocytes served as effector and target cells, respectively. The Ca2+-dependent phagocytosis was inhibited by aminosaccharides and their acetylated forms,l-fucose, laminarin (a β-1,3-glucan) and mannan. By omitting calcium from the buffer, the phagocytosis was reduced nearly to
zero. However, certain heterologous (commercial) lectins stimulated the process to levels detected in Ca2+-containing buffer. Knowing lectin targets on haemocytes and erythrocytes, lectin specificities and glycosylation, we could
infer the role of heterologous lectins in recognition: some lectins created bridges between carbohydrates on effector and
target cells whereas the others functioned as opsonins, i.e. they bound to saccharides on target cells and created in this
way attractive epitopes for haemocyte receptors; both lectin types enabled subsequent phagocytosis. Thus, Ca2+-dependent and-independent lectin-mediated recognition has been demonstrated. Infection byTrichobilharia szidati did not substantially impair the recognition process. The role of soluble lectins ofL. stagnalis origin (homologous lectins) remains to be solved. |
| |
Keywords: | Haemocytes Lymnaea Mollusc Recognition Snail Trichobilharzia |
本文献已被 SpringerLink 等数据库收录! |
|