preparation and characterization of cationic nanoemulsion&#45;encapsulated retinoic acid

Valutazione dell'immunogenicità dell'acido retinoico incapsulato con nanoemulsione nei topi

Adjuvants are often used to enhance the efficacy of a vaccine by stimulating the immune system to respond more strongly to the vaccine, thereby increasing immunity to a particular pathogen1. Nanoemulsion (NE) adjuvant refers to a colloidal dispersion system with thermodynamic stability by emulsifying a certain proportion of oil phase and aqueous phase to produce an emulsion in the form of water-in-oil (W/O) or oil-in-water (O/W)2. O/W nanoemulsion adjuvant can produce cytokines and chemokines at the injection site, induce the rapid aggregation and proliferation of important immune cells such as monocytes, neutrophils, and eosinophils, and enhance the immune response, and improve the immunogenicity of antigens3. Currently, three nanoemulsion adjuvants (MF59, AS03, and AF03) have been licensed for use in vaccines and have shown good safety and efficacy4.
However, mucosal immunity has been poorly addressed by the currently licensed adjuvant formulations in conventional parenteral vaccination5. Retinoic acid (RA) has been reported to induce intestinal homing of immune cells, but its low polarity, poor solubility in water, and poor light and thermal stability limit its use for robust enteric vaccination. Nanoemulsions offer opportunities to increase the bioavailability of highly lipophilic drugs, and the oil core of O/W emulsion adjuvants is suitable for dissolving non-polar substances such as RA6. Therefore, nanoemulsions can be used as carriers for RA in order to achieve the dual response effect of systemic immunity and mucosal immunity.
Compared to neutral or anionic delivery systems, cationic delivery systems have relatively efficient antigen encapsulation and delivery capabilities, which can enhance the immunogenicity of antigens7,8,9. The cationic surface charge of a variety of adjuvant systems is important for their adjuvant effects10,11,12. The cationic charge is an important factor in prolonging vaccine retention at the injection site, increasing antigen presentation and prolonging the stimulation of cellular immunity in the body12.
Based on the above considerations, we developed a cationic nanoemulsion to effectively co-deliver RA and antigens. The particle size and zeta potential of the nanoemulsion were determined using dynamic light scattering (DLS), and the systemic and mucosal immune responses of the nanoemulsion combined with OVA were evaluated by intramuscular injection13.

Autore in primo piano: Sviluppo e valutazione di un sistema di acido retinoico incapsulato con nanoemulsione cationica per la vaccinazione della mucosa

Acido retinoico incapsulato con nanoemulsione cationica come adiuvante per promuovere risposte sistemiche e mucose specifiche per le OVA

We are working on a mucosal vaccine that produces an immune response as the set of infection, which has the potential to prevent infection and interrupt transmission. We have developed a catatonic nanoemulsion-encapsulated retinoic acid delivery system immunization with ovalbumin by intramuscular injection, which triggers both systemic and mucosal immune responses. In future studies, animal models of intestinal-related diseases can be used to further evaluate the effect and the mechanism of a cationic nanoemulsion-encapsulated retinoic acid in enhancing vaccine protection.

Preparazione e caratterizzazione dell'acido retinoico incapsulato con nanoemulsione cationica

Iniziare la preparazione dell'acquifase sciogliendo 0,15 grammi di polisorbato 80 in 28,2 millilitri di PBS mescolando a 40 gradi Celsius. Per preparare la formulazione in fase oleosa, sciogliere il trioleato di sorbitano 85 DOTAP e l'acido retinoico nello squalene mescolando a 40 gradi Celsius. Quindi, aggiungere goccia a goccia la fase acquiescente a un millilitro al minuto alla fase oleosa agitando a 1400 giri/min per la preparazione dell'emulsione di olio primario e acqua.Preemulsionare la miscela utilizzando un emulsionante ad alto taglio a 30.000 giri/min per sei minuti. Trattare l'emulsione primaria di olio e acqua con un omogeneizzatore ad alta pressione per 12 cicli a 900 bar per ottenere una nano emulsione omogenea. Raccogliere l'emulsione in un pallone da 50 millilitri e sterilizzarla con filtro attraverso una siringa con filtro in PES da 0,2 micron.Collegare il pallone alla linea schlink attraverso il catetere, ruotando il rubinetto a tre vie per collegare il sistema al tubo a vuoto. Accendere la pompa del vuoto per creare il vuoto nel pallone. Quindi ruotare il rubinetto a tre vie per collegare il sistema al tubo di argon e riempirlo di argon.Rimettere il tappo dei flaconi e sigillarlo con una pellicola di paraffina. Avvolgere il pallone nella carta stagnola e conservarlo a 40 gradi Celsius. Accendere lo strumento di diffusione dinamica della luce e attendere 30 minuti affinché la sorgente di luce laser si stabilizzi.Diluire la nanoemulsione 50 volte con acqua ultrapura e aggiungere un millilitro di campione alla cella campione corrispondente. Sullo strumento, impostare la temperatura a 25 gradi Celsius. Scegliere l'acqua come mezzo di dispersione e le stoviglie di plastica monouso come cella di misura.Caricare i campioni e misurare la dimensione delle particelle. Riportare come risultato il valore medio di tre misurazioni ripetute per ciascun campione.

Research

JoVE Journal

Immunology and Infection

Preparation and Characterization of Cationic Nanoemulsion&#45;Encapsulated Retinoic Acid

Cationic Nanoemulsion-Encapsulated Retinoic Acid as an Adjuvant to Promote OVA&#45;Specific Systemic and Mucosal Responses

Cationic nanostructures have emerged as an adjuvant and antigen delivery system that enhances dendritic cell maturation, ROS generation, and antigen ...

Ricerca

Immunologia e infezioni

Evaluation of Ovalbumin-Specific Antibodies in Mice After Intramuscular Administration of Cationic Nanoemulsion&#45;Encapsulated Retinoic Acid

Valutazione degli anticorpi specifici dell'ovoalbumina nei topi dopo somministrazione intramuscolare di acido retinoico incapsulato con nanoemulsione cationica