Study On The Immune Enhancement Effect Of Layered Double Hydroxides On Protein Vaccines

Layered double hydroxide nanocarriers have received increasing attention due to their special lamellar structure and properties in drug carriers,gene delivery,and nanovaccines.Based on the controllable preparation of hydrotalcite-like crystal materials,this paper analyzed the loading capacity and influencing factors of nanocarriers on protein through the assembly process of pattern protein OVA and LDH,and verified the immune enhancement effect of LDH.Taking pertussis single antigen PT as an example for the first time,the immune adjuvant enhancement effect and possible mechanism were further analyzed in terms of immune does,immune type.The preparation and characterization results of layered double hydroxide nanoparticles show that co-precipitation can synthesize regular hexagonal nanocrystals with uniform dispersion and controllable particle size,and a stable LDH suspension with an average particle diameter of 100 nm and an interlayer distance of 0.764 nm can be obtained under conditions of 4 degrees co-precipitation and 100 degrees hydrothermal 16 hours.Protein assembly and immune effect experiments show that OVA protein is adsorbed on the surface of the positively charged laminate by electrostatic interaction with the laminate.By changing the adsorption condition,it was found that within 4h,when the p H of the OVA solution was 10,the ability of LDH to adsorb the protein OVA was stronger.Increasing the specific surface area of the particles could increase the amount of protein.In the model antigen immunization,LDH nanoparticles exert a sustained immune enhancement effect.Immunoassay of pertussis single antigen PTd shows,LDH at a group of 280ug/dose produced the same immune-enhancing effect as 350ug/dose of aluminum hydroxide.Meanwhile,the LDH:PTd ratio was in the range of 8:1 to 12:1,and there was no dose dependence on the immune adjuvant activity of LDH within 5 weeks.Based on the detection of typing antibody,it was proved that LDH-protein complex on the micron level was the same as aluminum adjuvant,both of which showed the adjuvant activity to enhance the specific humoral immune response.Few studies have reported on LDH as an adjuvant for protein vaccine.The results of this paper provide a basis for the application of LDH as an adjuvant for protein vaccine,which has important research significance.