S8 - Symposium 3

Isolation and characterization of extracellular vesicles (EVs) derived from lactobacilli

Mobili, P. - Hugo,A.A

Centro de Investigación y Desarrollo en Ciencia y Tecnologia de los Alimentos (CIDCA) (CONICET-UNLP-CIC) calle 47 esq.116 - La Plata, Buenos Aires, Argentina
Contacto: ahugo@biol.unlp.edu.ar

Lactobacilli are Gram-positive non-pathogenic bacteria that exhibit a GRAS (Generally Recognized as Safe) status. They possess a fermentative metabolism that has been used since ancient times for the production of fermented foods. Several lactobacilli strains are typical probiotic bacteria and produce extracellular vesicles (EVs). This work aims to isolate and characterize EVs derived from a potentially probiotic lactobacillus, Lactiplantibacillus plantarum (CIDCA 83114). 

The isolated EVs had an average size of 120 nm (determined by DLS) and a zeta potential value of -11 mV. Their structure was very stable, exhibiting only a slight size increase during storage for 28 days at 4ºC. Through the disruption of the vesicles and subsequent isolation of the components, it was determined that, in addition to lipids, the EVs contain proteins, DNA and RNA (the latter in quantities up to 15 times greater than DNA). The FTIR analysis revealed that EVs composition is qualitatively different from that of protoplasts obtained through the lysis of the same bacteria. 

We also evaluated the biological effect of L. plantarum EVs. The EVs exhibited an immunomodulatory effect by reducing CCL-20 expression in cultured human enterocyte cells (Caco-2 Luc). 

Lactiplantibacillus plantarum (CIDCA 83114) had well-documented probiotic effects. Our studies shed light on the properties of their derived EVs, which could have different, complementary, or synergistic effects.