There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.
Abstract
Evidence for the presumed linkage between the enigmatic rodlet cells of fish and exposure
to helminths is anecdotal and indirect. We evaluated the proliferation and development
of rodlet cells in the optic lobes of fathead minnows exposed to cercariae of Ornithodiplostomum
ptychocheilus. Mean rodlet cell densities (ca. 10/mm(2)) in the optic lobes were similar
between unexposed controls and minnows with 1- and 2-week old infections. Rodlet cell
densities increased at 4 weeks p.i., reaching maxima (ca. 200/mm(2)) at 6 weeks p.i.,
followed by a decline at 9 weeks. This temporal pattern of proliferation and maturation
paralleled the development of metacercariae within the optic lobes. Unencysted metacercariae
develop rapidly within tissues of the optic lobes for approximately 4 weeks after
penetration by cercariae, then shift to the adjacent meninges to encyst. The former
stage is associated with tissue damage, the latter with massive inflammation of the
meninges. Thus, peak densities and maturation of rodlet cells correspond to the period
when inflammation of the meninges caused by the large metacercarial cysts is at a
maximum. Our results support recent contentions that rodlet cells comprise part of
the host inflammatory defence response.
2009 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights
reserved.