Characterization of extracellular vesicles from Lactiplantibacillus plantarum

Abstract

We investigated the characteristics and functionalities of extracellular vesicles (EVs) from Lactiplantibacillus plantarum (previously Lactobacillus plantarum) towards host immune cells. L. plantarum produces EVs that have a cytoplasmic membrane and contain cytoplasmic metabolites, membrane and cytoplasmic proteins, and small RNAs, but not bacterial cell wall components, namely, lipoteichoic acid and peptidoglycan. In the presence of L. plantarum EVs, Raw264 cells inducibly produced the pro-inflammatory cytokines IL-1β and IL-6, the anti-inflammatory cytokine IL-10, and IF-γ and IL-12, which are involved in the differentiation of naive T-helper cells into T-helper type 1 cells. IgA was produced by PP cells following the addition of EVs. Therefore, L. plantarum EVs activated innate and acquired immune responses. L. plantarum EVs are recognized by Toll-like receptor 2 (TLR2), which activates NF-κB, but not by other TLRs or NOD-like receptors. N-acylated peptides from lipoprotein19180 (Lp19180) in L. plantarum EVs were identified as novel TLR2 ligands. Therefore, L. plantarum induces an immunostimulation though the TLR2 recognition of the N-acylated amino acid moiety of Lp19180 in EVs. Additionally, we detected a large amount of EVs in the rat gastrointestinal tract for the first time, suggesting that EVs released by probiotics function as a modulator of intestinal immunity.

Orally Deliverable Sequence-Targeted Fucoxanthin-Loaded Biomimetic Extracellular Vesicles for Alleviation of Nonalcoholic Fatty Liver Disease

“…The particle sizes of LpEVs and GA-LpEVs were determined using DLS, which was approximately 126 and 173 nm, respectively (Figure D). As shown in Figure E, the TEM images revealed that LpEVs exhibited a typical round or cup-shaped morphology, consistent with the previous research. , After GA modification, the GA-LpEVs exhibited a similar structure. The SEM images also demonstrated the spherical morphologies of both LpEVs and GA-LpEVs (Figure F).…”

Extracellular Vesicles of Probiotics: Shedding Light on the Biological Activity and Future Applications

“…These studies showed the protective effect of probiotic EVs on atopic dermatitis [ 139 ] and various intestinal pathologies (chemoresistant colorectal cancer [ 140 ] or intestinal infections made by enterotoxigenic E. coli [ 141 ]). It was also noticed that probiotic EVs have a strong immunomodulatory effect on the human body (including the intestines) [ 142 ], and that they can be used in the design of innovative vaccines against infectious diseases [ 143 ] and cancers [ 122 ]. In the last publication, attention was drawn to the participation of prophages in the secretion of EVs by the tested probiotic bacteria [ 144 ].…”

Bacterial Extracellular Vesicles in the Regulation of Inflammatory Response and Host-Microbe Interactions

“…This is exemplified by how L. plantarum EVs cause the decrease of proinflammatory cytokine IL-6 induced by S. aureus EVs in immune cells and skin cells (103). Notably, despite being probiotic and providing benefits to the host, not all Lactobacillus bacteria have anti-inflammatory properties, as L. plantarum EVs induce not only the anti-inflammatory cytokine IL-10 but also the proinflammatory cytokines IL-1β and IL-6 to activate the host immune system (101). Furthermore, L. plantarum EVs potentially use proteomic sections of Lp19180, a lipoprotein found in the cellular membrane, as a ligand of TLR2 to induce the NF-κB pathway (101).…”