Impact of oral probiotic Lactobacillus acidophilus vaccine strains on the immune response and gut microbiome of mice
Autoři:
Zaid Abdo aff001; Jonathan LeCureux aff001; Alora LaVoy aff001; Bridget Eklund aff001; Elizabeth P. Ryan aff002; Gregg A. Dean aff001
Působiště autorů:
Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
aff001; Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, Colorado, United States of America
aff002
Vyšlo v časopise:
PLoS ONE 14(12)
Kategorie:
Research Article
doi:
https://doi.org/10.1371/journal.pone.0225842
Souhrn
The potential role of probiotic bacteria as adjuvants in vaccine trials led to their use as nonparenteral live mucosal vaccine vectors. Yet, interactions between these vectors, the host and the microbiome are poorly understood. This study evaluates impact of three probiotic, Lactobacillus acidophilus, vector strains, and their interactions with the host’s immune response, on the gut microbiome. One strain expressed the membrane proximal external region from HIV-1 (MPER). The other two expressed MPER and either secreted interleukin-1ß (IL-1ß) or expressed the surface flagellin subunit C (FliC) as adjuvants. We also used MPER with rice bran as prebiotic supplement. We observed a strain dependent, differential effect suggesting that MPER and IL-1β induced a shift of the microbiome while FliC had minimal impact. Joint probiotic and prebiotic use resulted in a compound effect, highlighting a potential synbiotic approach to impact efficacy of vaccination. Careful consideration of constitutive adjuvants and use of prebiotics is needed depending on whether or not to target microbiome modulation to improve vaccine efficacy. No clear associations were observed between total or MPER-specific IgA and the microbiome suggesting a role for other immune mechanisms or a need to focus on IgA-bound, resident microbiota, most affected by an immune response.
Klíčová slova:
Immune response – Immunologic adjuvants – Lactobacillus – Microbiome – Probiotics – Rice – Vaccination and immunization – Vaccines
Zdroje
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