Lectin-reactive components of the microsporidian Glugea plecoglossi and their relation to spore phagocytosis by head kidney macrophages of ayu Plecoglossus altivelis.

We investigated the reactivity of lectins to spores of Glugea plecoglossi from ayu Plecoglossus altivelis. Smear preparations of purified spores were treated with 8 kinds of lectins. Lectin blots were used to detect glycoproteins of spore lysates. In addition, lectin-treated spores were applied to head kidney macrophages of ayu, and the percentage of phagocytosis (PP) was calculated and compared with the control. Two lectins (ConA, WGA) reacted with the surface of the spores, and a major band (55 kDa) and some minor bands were visualized on blots after treatment with these. PP was decreased after ConA treatment. From these results, we suggest that G. plecoglossi spores can be phagocytized by ayu head kidney macrophages via ConA-reactive glycoprotein-mediated recognition.