Autophagy Is a Defense Mechanism Inhibiting Invasion and Inflammation During High-Virulent Haemophilus parasuis Infection in PK-15 Cells

In this study, we sought to investigate whether SH0165 (serovar 5, high-virulent strain) and HN0001 (serovar 6, non-virulent strain) infection induces autophagy and the specific role of autophagy in bacterial invasion and inflammation during H. parasuis infection. Moreover, we explored the mechanism underlying autophagy regulated inflammation through inflammatory signaling cascades during H. parasuis infection. This observation could provide useful information for further understanding the role of autophagy in H. parasuis infection and improve our knowledge of new strategies against this pathogen. Materials and Methods Bacterial and Cells Culture Clinical isolated strains of H. parasuis SH0165 (serovars 5, high-virulent clinical strain) and HN0001(serovars 6, non-virulent clinical strain) (Cai et al., 2005) were cultured in tryptic soy broth (TSB; Difco Laboratories, Detroit, MI, USA) supplemented with 5% bovine serum and 0.2 mg/ml nicotinamide adenine dinucleotide (NAD) at 37°C overnight. Porcine kidney (PK-15) cells were maintained at 37°C and 5% CO2 in Dulbecco's Modified Eagle Media (DMEM, Gibco), supplemented with 10% fetal bovine serum (FBS, Gibco), 100 U/mL penicillin, and 10μg/mL streptomycin. Reagents, Antibodies, and siRNA Rapamycin (Rapa), 3-methyladenine (3MA), chloroquine (CQ), and Bafilomycin A1 (Baf-A1) were purchased from MedChem Express (Monmouth Junction, NJ, USA). Cells were pretreated with 1 μM rapamycin, 3 �...
Source: Frontiers in cellular and infection microbiology - Category: Microbiology Source Type: research