Ons. doi:10.1371/journal.pone.0047724.gP. aeruginosa Enhanced DNA Vaccine ImmunoreactivityFigure 6. Avidity of the anti-Env IgG raised by the different PA-MSHA concentrations. Sera obtained from inoculated mice were analyzed for 2-inoculation (A) and 3-inoculation regimens (B) in an HIV Env-specific NaSCN-displacement ELISA. Assays used serum samples from each mouse at a dilution of 1:100. Data points are the average of three independent assays 6 standard error. doi:10.1371/journal.pone.0047724.gduring early 1676428 stages of immunization. However, further studies are needed to clearly characterize Th2-type activity by ELISPOT. Finally, the vaccination schedule also had an effect on the adjuvant properties of PA-MSHA. The addition of the third inoculation most clearly improved humoral responses, Indolactam V particularly in low-dose groups, rather than cellular responses. While all dose levels failed to enhance humoral responses in the two-inoculation strategy, three inoculations of 102 CFU PA-MSHA induced the strongest antibody response, and even 108 CFU PA-MSHA retained a low humoral immune response. As well, antibody maturation was clearly enhanced by the third inoculation, as seen in the increased antibody avidity (Fig. 6 B). In sum, the immune response profile and antibody avidity of low doses of PA-MSHA (102 or 104 CFU) makes it an attractive candidate strategy for use as an 25837696 HIV-1 DNA vaccine adjuvant. In particular, the difference in immune response at two inoculations (a predominantly cellular response) and at three inoculations (a predominantly humoral response) suggests potential in tailoring the adjuvant strategy to the particular needs of a given vaccine, disease, or patient. It may also be useful for employing PA-MSHA in a combination of multiple adjuvants to control different immune responses at various time-points in the vaccination schedule. A vaccine regimen pre-designed to incorporate several adjuvants according to their particular characteristics may provide a promising direction for future HIV vaccine research.described previously. After that, cells were 
stained with anti-mouse CD3-PerCP and anti-CD8a-FITC antibodies. After permeabilization, cells were stained for intracellular anti-IFN-c-APC and antiIL2-PE and fixed. After 3687-18-1 web washing twice, samples were resuspended with PBS and immediately analyzed on a FACS Aria cytometer. (TIF)Figure S2 Env-specific IFN-c T-cells and antibodiesinduced by co-administration of DNA vaccine and adjuvant. Data are shown as mean 6 SD (n = 6 mice/group). After the third immunization, IFN-c production of splenic lymphocyte was determined by ELISPOT assay (Fig. S2A) and Env-specific binding antibody was determined by ELISA (Fig. S2B). Six- to eight-week-old female BALB/c mice (Vital River Laboratories) were randomly divided into 5 groups with six mice in each group. Group 1:50 mg pDVRI1.0-gp1455m +50 ml PBS; Group 2:50 ml 108 CFU PA-MSHA +50 ml PBS; Group 3:50 
mg pDVRI1.0-gp1455m +50 ml 108 CFU PA-MSHA in separated legs; Group 4:50 mg pDVRI1.0-gp1455m +50 ml 108 CFU PA-MSHA in premixed; Group 5:50 mg pDVRI1.0gp1455m +50 ml 108 CFU PA-MSHA simultaneously. (TIF)AcknowledgmentsThe authors wish to thank Dr. Jing Sun and Dr. Dang Li for their valuable suggestions on this study, to Zhiyong Xu, Zhou Zhang and Hong Peng for their assistances with animal experiment, and to Jenny H His, Rebecca Armstrong and Dr. Lena Yao for their critical reading and correcting of manuscript.Supporting InformationFigure S1 Env-specific ce.Ons. doi:10.1371/journal.pone.0047724.gP. aeruginosa Enhanced DNA Vaccine ImmunoreactivityFigure 6. Avidity of the anti-Env IgG raised by the different PA-MSHA concentrations. Sera obtained from inoculated mice were analyzed for 2-inoculation (A) and 3-inoculation regimens (B) in an HIV Env-specific NaSCN-displacement ELISA. Assays used serum samples from each mouse at a dilution of 1:100. Data points are the average of three independent assays 6 standard error. doi:10.1371/journal.pone.0047724.gduring early 1676428 stages of immunization. However, further studies are needed to clearly characterize Th2-type activity by ELISPOT. Finally, the vaccination schedule also had an effect on the adjuvant properties of PA-MSHA. The addition of the third inoculation most clearly improved humoral responses, particularly in low-dose groups, rather than cellular responses. While all dose levels failed to enhance humoral responses in the two-inoculation strategy, three inoculations of 102 CFU PA-MSHA induced the strongest antibody response, and even 108 CFU PA-MSHA retained a low humoral immune response. As well, antibody maturation was clearly enhanced by the third inoculation, as seen in the increased antibody avidity (Fig. 6 B). In sum, the immune response profile and antibody avidity of low doses of PA-MSHA (102 or 104 CFU) makes it an attractive candidate strategy for use as an 25837696 HIV-1 DNA vaccine adjuvant. In particular, the difference in immune response at two inoculations (a predominantly cellular response) and at three inoculations (a predominantly humoral response) suggests potential in tailoring the adjuvant strategy to the particular needs of a given vaccine, disease, or patient. It may also be useful for employing PA-MSHA in a combination of multiple adjuvants to control different immune responses at various time-points in the vaccination schedule. A vaccine regimen pre-designed to incorporate several adjuvants according to their particular characteristics may provide a promising direction for future HIV vaccine research.described previously. After that, cells were stained with anti-mouse CD3-PerCP and anti-CD8a-FITC antibodies. After permeabilization, cells were stained for intracellular anti-IFN-c-APC and antiIL2-PE and fixed. After washing twice, samples were resuspended with PBS and immediately analyzed on a FACS Aria cytometer. (TIF)Figure S2 Env-specific IFN-c T-cells and antibodiesinduced by co-administration of DNA vaccine and adjuvant. Data are shown as mean 6 SD (n = 6 mice/group). After the third immunization, IFN-c production of splenic lymphocyte was determined by ELISPOT assay (Fig. S2A) and Env-specific binding antibody was determined by ELISA (Fig. S2B). Six- to eight-week-old female BALB/c mice (Vital River Laboratories) were randomly divided into 5 groups with six mice in each group. Group 1:50 mg pDVRI1.0-gp1455m +50 ml PBS; Group 2:50 ml 108 CFU PA-MSHA +50 ml PBS; Group 3:50 mg pDVRI1.0-gp1455m +50 ml 108 CFU PA-MSHA in separated legs; Group 4:50 mg pDVRI1.0-gp1455m +50 ml 108 CFU PA-MSHA in premixed; Group 5:50 mg pDVRI1.0gp1455m +50 ml 108 CFU PA-MSHA simultaneously. (TIF)AcknowledgmentsThe authors wish to thank Dr. Jing Sun and Dr. Dang Li for their valuable suggestions on this study, to Zhiyong Xu, Zhou Zhang and Hong Peng for their assistances with animal experiment, and to Jenny H His, Rebecca Armstrong and Dr. Lena Yao for their critical reading and correcting of manuscript.Supporting InformationFigure S1 Env-specific ce.