DEVELOPMENT AND USE OF AN ESTABLISHED CELL-LINE OF THE LEAFHOPPER CIRCULIFER TENELLUS TO CHARACTERIZE SPIROPLASMA-CITRI - VECTOR INTERACTIONS

A continuous cell line of embryonic origin from the leafhopper Circuli fer tenellus, CT 1, was established using a protocol modified from thr ips cell culture. The line was used to develop an in vitro model to ex amine the mode of entry of the plant pathogenic mollicute Spiroplasma citri into insect host cells. Confluent monolayers were achieved in 5- 6 months using a simple medium developed for maintaining established l eafhopper cell. lines. The newly established CT 1 line, and that of an other leafhopper, Nephotettix cincticeps, were exposed to S. citri and examined by electron microscopy. S. citri was found to cytadhere and to be present in apparent invaginations of the host cell membranes of cell. lines of both leafhopper species, supporting the hypothesis that this pathogen enters its insect host via endocytosis. (C) 1998 Academ ic Press.