Adhesion and invasion of Clostridium perfringens type A into epithelial cells

Abstract

Clostridium perfringens is the causative agent for necrotic enteritis. It secretes the major virulence factors, and α- and NetB-toxins that are responsible for intestinal lesions. The TpeL toxin affects cell morphology by producing myonecrosis, but its role in the pathogenesis of necrotic enteritis is unclear. In this study, the presence of netB and tpeL genes in C. perfringens type A strains isolated from chickens with necrotic enteritis, their cytotoxic effects and role in adhesion and invasion of epithelial cells were evaluated. Six (27.3%) of the 22 C. perfringens type A strains were harboring the tpeL gene and produced morphological alterations in Vero cells after 6 h of incubation. Strains tpeL (−) induced strong cell rounding after 6 h of incubation and produced cell enlargement. None of the 22 strains harbored netB gene. All the six tpeL (+) gene strains were able to adhere to HEp-2 cells; however, only four of them (66.6%) were invasive. Thus, these results suggest that the presence of tpeL gene or TpeL toxin might be required for the adherence of bacteria to HEp-2 cells; however, it could not have any role in the invasion process.

Culturable Bacterial Community on Leaves of Assam Tea (Camellia sinensis var. assamica) in Thailand and Human Probiotic Potential of Isolated Bacillus spp.

“…Cell adhesion was carried out by using the Vero cell line, a kidney epithelial cell. The assay was performed according to the modified method of Llanco et al [ 29 ]. The Vero cells were cultivated in 6-well plates with Dulbecco’s modified Eagle medium (DMEM, Gibco ® , Loughborough, UK) containing 10% ( v/v ) fetal bovine serum (Capricorn Scientific GmbH, Ebsdorfergrund, Germany) and 1% ( v/v ) penicillin/streptomycin (Caisson Laboratories, Inc., Smithfield, UT, USA), and incubated at 37 °C in a CO 2 incubator for 48 h. Afterwards, the harvested cells were adjusted equivalent to 1 × 10 5 cell/well prior to incubation overnight at 37 °C in a CO 2 incubator, and then triple washed with 1X PBS.…”

Partial rpoB Gene Sequencing Identification and Probiotic Potential of Floricoccus penangensis ML061-4 Isolated from Assam Tea (Camellia sinensis var. assamica)

“…The bacterial adherence assay was performed following the method described by Llanco et al . 63 with modifications. Briefly, the African green monkey kidney cell line (Vero cell) was grown in Dulbecco’s modified eagle medium (DMEM) (Gibco®, Life Technologies TM , UK) supplemented with penicillin/streptomycin and fetal bovine serum (FBS) (Sigma-Aldrich™) and incubated at 37 °C in a CO 2 incubator.…”

Prevalence of netB-positive Clostridium perfringens in Italian poultry flocks by environmental sampling

“…Interestingly, all netB-positive isolates were from flocks with the subclinical form of NE, with a moderate increase of mortality rate but an absence of typical pathologic findings of enteritis. In contrast, when severe NE was observed during autopsy of deceased birds (flocks [11][12][13][14][15], no netB gene was detected. We cannot rule out that intense dysbiosis could affect the intestinal microbiota, resulting in a decrease of the netB-positive clostridia initially responsible for the infection.…”

“…The netB-positive extracts came from flocks 8 (turkey) and 10 (broiler), in which only mild clinical signs of enteric disorder were noted, but no typical necrotic lesions were observed. Curiously, C. perfringens isolates recovered from carcasses with severe intestinal lesions suggestive of necrotic enteritis (flocks [11][12][13][14] were netB negative.…”