The In vitro Cultivation of Nippostrongylus muris to the Adult Stage

Abstract

The cultivation in vitro of nematode parasites of vertebrates should prove to be an important tool which might ultimately be used in the study of many aspects of nematode biology, and in the elucidation of some of the complex factors which are involved in the parasite-host relationship. The reviews by Lapage (1937), Hoeppli, Feng and Chu (1938), Hobson (1948), and von Brand (1952) summarized many of the early studies which were concerned primarily with survival of larval or adult nematodes under various conditions. More recently, with the development of axenic procedures, progress has been made in achieving growth and prolonged survival of several species. Glaser and Stoll (1938a, b) and Stoll (1940) were able to cultivate the free-living stages of Haeimonchus contortus, and also obtained partial differentiation of the stages of this organism. The axenic cultivation of the free-living stages of five other strongyles was subsequently reported: Ancylostoma braziliense by Lawrence (1948), and A. caninum, A. duodenale, Nippostrongylus muris, and Necator americanus by Weinstein (1949, 1953, 1954). Using roller tube tissue culture as a tool, Weller (1943) found that Trichinella spiralis larvae underwent molting, and some worms showed differentiation comparable to early development in the gut. Extremely long periods of survival have been attained for the larva of Eustrongylides ignotus by von Brand and Simpson (1945), some remaining alive for as long as 4 years. Pitts and Ball (1955) have reported slight growth of the newly hatched larvae of Ascaris lumbricoides. The studies on Neoaplectana glaseri (Glaser, 1940; Stoll, 1953) and N. chresima (Glaser, McCoy and Girth, 1942), nematode parasites of insects, and on the freeliving organisms, Rhabditis pellio and R. briggsae (Dougherty and Calhoun, 1948b; Dougherty, 1950; Dougherty and Keith, 1953) have contributed considerably to the fundamental understanding of the nutritional requirements of nematodes. The present study reports the axenic development of Nippostrongylus muris from the egg to the adult, with primary emphasis on the cultivation of the stages corresponding to the parasitic part of the cycle. Although some information will be presented on the development of the free-living stages, a more detailed account of this phase will be given in a separate publication.