The starter culture was diluted at 1 : 100 in HI broth and grown with shaking at 33 °C to an OD610 nm of ∼0.5 (exponential growth phase). Bacteria were collected by centrifugation, washed once with phosphate-buffered saline (PBS) (Sigma, St. Louis, MO), suspended in PBS and inactivated by overnight incubation at 25 °C with neutral buffered formalin (0.5% final concentration) (Sigma). The cells were washed twice with PBS and stored at 4 °C. Formalin treatment was used to inactivate V. vulnificus because growth would confound assay results due to cytotoxicity (Shin et al., 2004). Vibrio vulnificus (CFU mL−1) were quantified by plating aliquots of serial

dilutions on HI agar before formalin treatment. Blood was collected aseptically from two to three male mice (10–13 weeks of age) per each genotype (i.e. WT, TLR4 KO, and MyD88 KO) in heparin-flushed ABC294640 molecular weight selleck chemicals llc syringes and pooled to minimize variability. Mouse blood (25 μL) was diluted to 200 μL with Roswell Park Memorial Institute

(RPMI) medium 1640 (Invitrogen Corp., Grand Island, NY) (negative control), RPMI medium containing formalin-inactivated V. vulnificus ATCC 27562 cells, or RPMI medium containing 20 ng (100 ng mL−1) Escherichia coli 0111 : B4 purified lipopolysaccharide (Sigma) (positive control). Duplicate samples were incubated at 34 °C with gentle agitation for 6 and 24 h. Cell-free supernatants were collected following centrifugation and assayed in duplicate for mouse TNFα with a commercial enzyme-linked immunosorbent assay (ELISA) kit (R&D Systems Inc., Minneapolis, MN) at the UNC-CH Immunotechnologies Core Facility. Whole blood assays were repeated at least once. Statistical significance of results was evaluated with the unpaired, two-tailed t-test for analysis of two groups or anova for analysis of more than two groups (graphpad prism 4, GraphPad Software Inc., San Diego, CA). A P-value of <0.05 was considered significant. Splenocytes were prepared from pooled spleens of two male mice (10–12 weeks of age) per each genotype

(i.e. WT, MyD88 KO, and TLR4 KO). Following lysis of red blood cells, splenocytes were washed, suspended in RPMI medium containing 5% heat-inactivated fetal bovine serum (Fisher Scientific, Pittsburgh, PA), and seeded at 5 × 105 cells in 200 μL per well. ADAMTS5 After a 24-h incubation at 37 °C in 5% CO2 with RPMI medium only, 1 × 106 formalin-inactivated V. vulnificus ATCC 27562 cells, or 20 ng E. coli lipopolysaccharide, cell-free supernatants from duplicate samples were collected and assayed in duplicate for TNFα by ELISA. Splenocyte assays were repeated an additional time. Statistical significance of results was evaluated with the unpaired, two-tailed t-test for analysis of two groups or anova for analysis of more than two groups (graphpad prism 4). A P-value of <0.05 was considered significant. Vibrio vulnificus ATCC 27562 was grown with shaking in HI broth at 33 °C to exponential phase.