After one hour incubation at room temperature, the plates were washed five times with washing buffer, and incubated for an additional hour at room temperature after the addition of a 1:250,000 dilution of horseradish peroxidase (HRP)-conjugated goat anti-mouse IgG (Bethyl Inc.) to the wells of the microtiter plate. After washing five times, 3, 3’, 5, 5’ tetramethylbenzidine (TMB) substrate was added to visualize antigen-antibody reactions. The reaction was stopped with 0.18 M H2SO4, and the optical density was measured at 450 nm. Lymphocyte check details proliferation assay The lymphocyte proliferation assay was performed using

the described method [26]. Splenocytes harvested on day 7 and 42 post-immunization were used in the lymphocyte proliferation assay. IWP-2 order After harvesting, live splenocytes were determined by the trypan blue exclusion technique and counting with a hemocytometer. Cells from both groups of mice were plated selleck products in a 96-well

U-bottom microtiter plate (Corning Inc., Corning, NY) at a cell density of 2 x 105 cells/well. The cells were treated with STM cell lysate (1 μg/ml) and incubated at 37°C with 5% CO2 for 48 hours. The STM cell lysate was created from a WT STM 14028 culture that was grown to an optical density (O.D.)600 of 1.0, washed twice with PBS, lysed by sonication, and quantitated using a Bradford Assay. The percentage of cell survival was determined using the CytoTox-Glo Cytotoxicity Assay (Promega, Madison, WI). Quantification of viable cells was determined by the formula: Signal from Viable Cells = Total Cytotoxicity Signal – Initial Cytotoxicity Signal. Cytokine profiling The cytokine profiling Baf-A1 was performed using a commercially based multiplex assay as described [12]. Th1 (IL-2 and IFN-γ) and Th2 (IL-4 and IL-10) cytokine levels were determined from mouse sera at day 7 and 42 using a multiplex

assay (Quansys Biosciences, Logan, UT). Cytokine production from splenocytes at day 7 and 42 was measured by plating splenocytes from both groups of mice in a microtiter plate at a cell density of 2 x 105 cells/well. The cells were treated with STM cell lysate (1 μg/ml) and incubated at 37°C with 5% CO2 for 48 hours. The levels of Th1 and Th2 cytokines in the culture supernatant were determined using a multiplex assay (Quansys Biosciences). Passive transfer of cells and sera Mice were bled for sera and splenocytes were harvested on day 42 post-immunization. Fifteen naïve mice were used with the mice being divided into three groups with five mice per group. Each group was inoculated via retro-orbital injection [27] with either 100 μl sterile PBS, 100 μl of sera from non-infected mice, or 100 μl of sera from mice immunized with the gidA mutant STM strain [28].