Open AccessIntracellular viability of toxigenic Corynebacterium diphtheriae strains in HEp‐2 cells
Author(s) -
Hirata Raphael,
Napoleão Fátima,
MonteiroLeal Luiz Henrique,
Andrade Arnaldo F.B,
Nagao Prescilla E,
Formiga Luiz Carlos D,
Fonseca Leila S,
MattosGuaraldi Ana Luíza
Publication year - 2002
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2002.tb11379.x
Subject(s) - corynebacterium diphtheriae , microbiology and biotechnology , intracellular , extracellular , biology , vacuole , bacteria , pertactin , cytochalasin , vibrio cholerae , diphtheria toxin , diphtheria , electroporation , pertussis toxin , toxin , cell , virology , biochemistry , cytoskeleton , genetics , vaccination , cytoplasm , g protein , gene , receptor
Corynebacterium diphtheriae , generally considered an extracellular coloniser, was evaluated for its ability to enter and survive within HEp‐2 monolayers by gentamicin protection assay. Intracellular viability of HC01 strain, isolated from endocarditis, was more expressive (2.59%) than observed in 241 (0.21%) and CDC‐E8392 (1.93%) strains. Electron microscopy of C. diphtheriae ‐infected HEp‐2 cells revealed intracellular bacteria inside membrane‐bound vacuoles. Bacterial internalisation was totally inhibited by 5 μM cytochalasin E and significantly inhibited by 100 μM genistein ( P <0.05). Therefore, C. diphtheriae presents the ability to survive within cultured epithelial cells and signalling cascade as well as actin polymerisation are required for entry of diphtheria bacilli into HEp‐2 cells.