Sequential infection and distribution of wound-tumor virus in the internal organs of a vector after ingestion of virus

Abstract

Fluorescent antibody techniques were used to detect wound-tumor virus (WTV) antigens in the hemolymph, brain, salivary glands, intestine, Malpighian tubules, ovaries, fat body, and mycetomes of the viruliferous leafhopper Agallia constricta Van Duzee. No antigens could be detected in the male reproductive organs. WTV antigens were localized in the cytoplasmic particulates of hemocytes and of fat body cells. Particles which stain specifically, by the fluorescent antiserum, in the hemolymph of viruliferous leafhoppers could be pelleted by low speed centrifugation. When insects were given a 1-day acquisition feed, WTV antigens were detected on the 4th day in a particular corner of the filter chamber of the intestine of some intestines. No positive reactions could be found in the hemolymph or any other organs at this time, or indeed before the 12th day. By the 12th day the entire filter chamber was filled with fluorescent particles and infection had extended from this part of the ventriculus to other adjacent parts of this organ. By the 14th day WTV antigens could be detected in fat body, brain, and Malpighian tubules, and on the 17th day in the salivary glands. Various internal organs were maintained in a culture medium, and some of them showed peristaltic movements for up to 3 weeks. When organs were isolated from viruliferous leafhoppers at least 4 weeks after the acquisition of WTV and maintained in vitro for 15 days, WTV antigens were detected in brain, salivary glands, intestine, Malpighian tubules, and ovaries. Fat body tissues and mycetomes tended to degenerate in the medium.