Detection of Progeny Immune Responses after Intravenous Administration of DNA Vaccine to Pregnant Mice

A number of factors influence the development of tolerance, including the nature, concentration and mode of antigen presentation to the immune system, as well as the age of the host. The studies were conducted to determine whether immunizing pregnant mice with liposome-encapsulated DNA vaccines had an effect on the immune status of their offspring. Two different plasmids (encoding antigens from HIV-1 and influenza virus) were administered intravenously to pregnant mice. At 9.5 days post conception with cationic liposomes, injected plasmid was present in the tissues of the fetus, consistent with trans-placental transfer. When the offspring of vaccinated dams were immunized with DNA vaccine, they mounted stronger antigen-specific immune responses than controls and were protected against challenge by homologous influenza virus after vaccination. Moreover, such immune responses were strong in the offspring of mothers injected with DNA plasmid 9.5 days after coitus. These results suggest that DNA vaccinated mothers confer the antigen-specific immunity to their progeny. Here we describe the methods in detail as they relate to our previously published work

Detennination of the Phase Change in the ^1H-NMR Relaxation Behavior of Dehydrating Soybean Seed Using the AIC Method

The physical state of water in dehydrating soybean seeds determined by the NMR relaxation times (T_1) was analyzed using AIC and a three phase regression model was the most. apporopriate. The first transition occurred at a 44% water content and the second at 18%. In the first phase, the water content 60% at the \u22physiological maturity\u22 stage, at which time developmental processes in the majority of seeds either cease or slow down. In the second phase, the seeds quickly lost loosely bound water from the cytoplasm during a very short period. In the third phase, a glassy state could represent a useful mechanism to trap residual water molecules and to prevent damaging interactions between cell components and thus T_1 , might increase at the glass transition point. The three phases demonstrating cytoplasmic water might thus correspond to desiceation tolerance with a different dchydration process