The early phase of tissue invasion by Trichuris muris (nematoda: Trichuroidea).

Eggs of Trichuris muris hatched when implanted directly into the ceca of mice. The hatched larvae had penetrated the epithelium 40 min after introduction of the eggs. It is certain that the larvae penetrated the epithelium lining the cecal glands after entering the glands. Since penetration through the surface or luminal epithelium was not observed, it may be that the larvae enter gland openings selectively before penetrating epithelial cells.