Nano-Encapsulated Antioxidant: Retinoic Acid as a Natural Mucosal Adjuvant for Intranasal Immunization against Chronic Experimental Toxoplasmosis

Tropical Medicine and Infectious Disease

article

Doaa E. Said¹  Eglal I. Amer¹  Eman Sheta²  Shaimaa Makled³  Fadwa M. Arafa¹  Hala E. Diab¹ 

[1] Department of Medical Parasitology, Faculty of Medicine, Alexandria University;Department of Pathology, Faculty of Medicine, Alexandria University;Department of Pharmaceutics, Faculty of Pharmacy, Alexandria University

关键词: Toxoplasma gondii;    retinoic acid;    vaccine;    mucosal;    IgA;    adjuvant;   

DOI  :  10.3390/tropicalmed8020106

学科分类：社会科学、人文和艺术（综合）

来源: mdpi

【 摘 要 】

The tight relationship between immunity and retinoid levels provides evidence on the critical role of retinoic acid (RA) in regulating immune activity, especially the mucosal one. Mucosal immune response is the key for determination of the outcome of infection, particularly against intracellular mucosal pathogens such as Toxoplasma gondii, where it plays a crucial role as a sentinel against parasite invasion. Herein, the immunomodulatory adjuvant role of RA was evaluated for prophylactic vaccination against chronic Toxoplasma infection. A quantity of 15 µg of RA pre-encapsulated with lipid-based nanoparticles (SLNs) was intranasally used in three doses, two weeks apart, as an adjuvant to the Toxoplasma lysate antigen (TLA). Afterward, mice were infected with 20 cysts of T. gondii (ME49 strain) and were sacrificed at the 4th week post-infection. Parasitological, immunological, biochemical, and histopathological studies were applied as vaccine efficacy measures. The protective role of the tested vaccine was noted using the statistically marked reduction in brain cyst count, accompanied by remarkable levels of protective IFN-γ and antibodies, with amelioration of infection-induced oxidative stress and brain pathology. Ultimately, this experiment outlined the prospective role of a novel, natural, nano-encapsulated and mucosal vaccine adjuvant RA-SLNs as a propitious candidate against chronic toxoplasmosis.

【 授权许可】

CC BY