Improved Aluminum Adjuvants Eliciting Stronger Immune Response When Mixed with Hepatitis B Virus Surface Antigens.

Adjuvants can regulate the immune response triggered by vaccines. Traditional aluminum adjuvants can induce humoral immunity, but they lack the ability to effectively induce Th1 cellular immunity, which is not conducive to the development of vaccines with improved protective effects. Aluminum adjuvants from different sources may have different physicochemical properties, and therefore, completely different immune responses can be triggered. This suggests that adjuvant recognition by the immune system and its responses are closely associated with the physicochemical properties of the adjuvant itself. To test this hypothesis, in this study, we developed a new method for preparing an aluminum adjuvant. This aluminum adjuvant has a pseudoboehmite structure, strong protein adsorption capacity, and excellent suspension stability. The adjuvant was tested using the hepatitis B virus surface antigen (HBsAg) as a model antigen for immunization; the results showed that this aluminum adjuvant effectively induced not only humoral immunity but also an outstanding cellular immune response. These results provide a reference for improving the efficacy of adjuvants.

A New Nano Adjuvant of PF3 Used for an Enhanced Hepatitis B Vaccine.

Recombinant protein vaccines, with highly pure ingredients and good safety, are gradually replacing some attenuated and inactivated vaccines in clinical practice. However, since their low immunogenicity of the recombinant proteins, adjuvants are often needed to enhance immune response after vaccination. Aluminum adjuvant has been widely used in some vaccines for decades, it can induce strong humoral immunity, but the deficiency of cellular immunity limits its application for some vaccines. Therefore, it is urgently needed to develop novel adjuvant to increase not only humoral but also cellular immune response. To address this, we designed and prepared a new nano adjuvant (PF3) through microfluidization by the combination of saponin (Ginsenoside Rg1) and oil-in-water nano emulsion (NE) in the present study. As compared to aluminum adjuvant, PF3 had stronger humoral and cellular immune induction effect because of high cellular uptake and activization of immune response pathways. Furthermore, PF3 showed better immune enhancement and acceptable biosafety equivalent to that of aluminum adjuvant. In addition, no obvious changes of PF3 were observed in size and zeta potential after 12 weeks storage at 4 and 37°C, demonstrating its high stability in vitro. This study provided an adjuvant platform to replace traditional aluminum adjuvant in design of recombinant vaccines.

Optical Density Value and Ratio as Novel Indexes for Nanoemulsion Sterile Filtration Process Control or Characterization.

Sterile filtration is an effective method to remove any microorganisms present during nanoemulsion preparation. However, it lacks effective control parameters. Here, we established a simple and rapid approach for the process control of nanoemulsion sterile filtration by utilizing optical density detection as a process control parameter. During sterile filtration, the optical density or optical density ratio of the filtrate were continuously monitored to explore the correlation between optical density and the emulsion content and the change in the optical density ratio before and after sterile filtration. In the emulsion stability test, the optical density ratio was determined. A good correlation was obtained between the optical density and the nanoemulsion content during sterile filtration, thereby reducing sterile filtration loss. The optical density ratio changed significantly after sterile filtration, indicating that it could be used as a process control parameter to monitor leakage during emulsion sterile filtration. The optical density ratio can be a characterization index for stability monitoring as it is more sensitive than particle size detection and more convenient than large particle detection. These parameters may be used for sterile filtration process control and as an index for nanoemulsion characterization. This approach overcomes the limitations of existing nanoemulsion characterization methods.

Unbalanced economic benefits and the electricity-related carbon emissions embodied in China's interprovincial trade.

Quantifying the economic benefits and environmental costs brought about by trade can help reveal the environmental inequalities behind regional trade. There have been many studies on the accounting of greenhouse gas emissions and pollutants embodied in regional trade, but there are insufficient studies analyzing the imbalance between the economic benefits and environmental costs embodied in trade. Electricity-related carbon emissions are the main contributor to global warming, explaining more than 40% of carbon emissions both globally and in China. This study uses the network approach and multiregional input-output (MRIO) model to quantify the electricity-related carbon emissions and value added embodied in China's interprovincial trade from 2007 to 2012 and also applies the regional environmental inequality (REI) index to measure the imbalance of electricity-related carbon emissions and economic benefits embodied in such trade. The results show that 20-80% of the electricity-related carbon emissions and 15-70% of the value added of a province's final demand are outsourced to other provinces. The major directions of the net value added and electricity-related carbon emissions embodied in China's interprovincial trade were from north to south and from the center to the east. Unequal bilateral interprovincial trade mainly occurred between inland provinces and developed provinces, and western provinces (such as Guizhou, Gansu, and Ningxia) suffered economic and environmental losses from interprovincial trade. This study can promote understanding of the distribution impacts of domestic trade on environmental costs and economic benefits and provide a reference for China's cross-provincial carbon emission mitigation policies.