A Comparative Study of the Effects of Al(OH)3 and AlPO4 Adjuvants on the Production of Neutralizing Antibodies (NAbs) against Bovine parainfluenza Virus Type 3 (BPIV3) in Guinea Pigs.

Aluminum-containing adjuvants are extensively used in inactive human and animal vaccines owing to their favorable immunostimulatory and safe properties. Nonetheless, there is controversy over the effects of different aluminum salts as an adjuvant for the bovine parainfluenza virus type 3 (BPIV3) vaccine. In order to find a suitable adjuvant, we studied the effects of two adjuvants (i.e., aluminum hydroxide [Al(OH)3] and aluminum potassium sulfate [AlPO4]) on the production of neutralizing antibodies (NAbs) for an experimental BPIV3 vaccine. The animals under study (Guinea pigs) were randomly assigned to five groups of experimental vaccines containing Al(OH)3 (AH), AlPO4 (AP), Al(OH)3-AlPO4 mixture (MIX), commercial vaccine (COM), and control (NS). The treatment groups were immunized with two doses of vaccine 21 days apart (on days 0 and 21), and the control group received normal saline under the same conditions. The animals were monitored for 42 days, and blood samples were then taken. The results indicated that all vaccines were able to induce the production of NAbs at levels higher than the minimum protective titer (0.6). An increase in titer was observed throughout the monitoring period. Moreover, an increase in both the level and mean titer of NAbs obtained from the vaccine containing Al(OH)3 adjuvant was significantly higher than in the other studied groups (P≤0.005). The comparison of NAbs titer in other groups did not display a significant difference. Considering the speed of rising and the optimal titer of NAbs production in the experimental vaccine, the Al(OH)3 adjuvant is a suitable candidate for preparing a vaccine against BPIV3 for immunization.

Amiloride inhibition of vacuolar Na+/H+ antiporter enhance salt stress in Zea mays L. seedlings.

The aim of this study to show the importance of salt intracellular compartmentation as a tolerance mechanism by inhibition of Na+/H+ antiporter system. In this research 4 day/old Zea mays L. seedlings (var. single cross 704) were exposed to 200 and 300 mM NaCl with and without 100 and 200 micromolar amiloride. After 48 h, the roots and shoots of seedlings were harvested separately. The changes of total Na+ absorption, the amount of malondialdehyde and the activity of antioxidant enzymes such as guaiacol peroxidase, ascorbate peroxidase and catalase were analysed. The results indicated that Na+ absorption has been increased by salt stress but was not influenced by amiloride. Malondialdehyde content and the activity of antioxidant enzymes such as guaiacol peroxidase, ascorbate peroxidase and catalase were increased in salt stressed plants specially in plants treated with salt and amiloride. Therefore salt stress has caused osmotic and oxidative stress in plants and amiloride as inhibitor of vacuolar Na+/H+ antiporter has been increased salt stress. Therefore we concluded that Na+ compartmentation in the cell is very important to reduce its damage in the cytosol and vacuolar Na+/H+ antiporter has an essential role in Na+ homeostasis in the cell by exporting excess Na+ to the vacuole.