Early work showed that N. australiensis, N. lovaniensis
and N. gruberi lysed cultured nerve cells in a contact-
dependent manner, followed by ingestion of the target
cells
(42)
. In addition, a highly pathogenic mouse-passaged
strain of N. fowleri destroyed B103 nerve cells by contact-
dependent lysis
(13)
.
Conversely, the cytopathologic effect
of axenically cultivated N. fowleri in B103 nerve cells
is a result of piecemeal ingestion (trogocytosis) of target
cells using a ‘food-cup’ structure on their surface (Figure
1). These observations support the idea that adhesion,
direct contact with target cells and the release of cytolytic
molecules are very important factors during the process
of cytopathogenicity of Naegleria
(43)
.