Review
Copyright ©The Author(s) 2021.
World J Gastroenterol. Nov 14, 2021; 27(42): 7247-7270
Published online Nov 14, 2021. doi: 10.3748/wjg.v27.i42.7247
Table 1 Examples of bacterial quorum sensing autoinducer and corresponding systems

AI
Example of producing bacteria
QS system
Bacterial QS-regulated processes
Ref.
Gram +AI peptideStaphylococcus aureusagrVirulenceNovick et al[155]
Listeria monocytogenesagrVirulenceAutret et al[156]
Clostridium perfringensagrVirulenceOhtani et al[157]
Enterococcus faecalisFsRVirulenceSifri et al[158]
Bacillus subtiliscomCompetenceMagnuson et al[159]
γ-butyrolactoneStreptomyces genusscbAntibioticsTakano et al[13]
scgMetabolismDu et al[14]
Gram -AI-1 (acyl-homoserine lactones)Vibrio fischeriLuxI/LuxRLuminescenceEngebrecht et al[16]
Vibrio harveyiLuxLM/LuxNLuminescenceMok et al[160]
VirulenceWaters and Bassler[161]
Pseudomonas aeruginosaLasI/LasRVirulence and biofilmGambello and Iglewski[162], Gambello et al[163], Winson et al[164], and Chapon-Hervé et al[165]
RhlI/RhlR
PQSPseudomonas aeruginosaPqsABCD/PqsRQS regulationPesci et al[166]
PyocyaninGallagher et al[167]
Iron homeostasisBredenbruch et al[168] and Diggle et al[169]
VirulenceGallagher et al[167] and Cao et al[170]
BiofilmDiggle et al[171]
IQSPseudomonas aeruginosaAmbBCDE/IqsRResponse to stressLee et al[172]
CAIVibrio (cholerae)CqsA/CqsSVirulenceNg et al[173]
AI-3EHEC O157:H7Qse/QseBCAttachment-effacementSperandio et al[19], Walters et al[21], and Kim et al[22]
EPEC O26:H11Qse/unknownUnknownKim et al[22], and Kaper and Sperandio[40]
AIEC LF82Qse/unknownUnknownKim et al[22]
Escherichia coli MG1655UnknownUnknownKim et al[22]
Escherichia coli BW25113UnknownUnknownKim et al[22]
Salmonella entericaQse/unknownUnknownKim et al[22], Kaper and Sperandio[40], and Walters and Sperandio[174]
Shigella flexneriQse/unknownUnknownKim et al[22], Kaper and Sperandio[40], and Walters and Sperandio[174]
Yersinia sp.Qse/unknownUnknownKim et al[22], Kaper and Sperandio[40], and Walters and Sperandio[174]
Gram + and -AI-2Vibrio harveyiLuxS/LuxPQBioluminescence, TSS, proteaseSurette et al[24], Mok et al[160], and Schauder et al[175]
Vibrio choleraeLuxS/LuxPQVirulence and BiofilmSchauder et al[175], Zhu et al[176], and Hammer and Bassler[177]
Enterococcus faecalisLuxS/LuxPQUnknownSurette et al[24], and Schauder et al[175]
EHECLuxS/LsrB (?)Attachment-effacementSchauder et al[175], and Bansal et al[178]
Salmonella entericaLuxS/LsrBPathogenicity and invasionMiller et al[26], Schauder et al[175], and Choi et al[179]
Table 2 Effects of quorum sensing molecules on different parameters of the intestinal epithelial barrier function
QS molecule
Effects
Ref.
Effects on the intestinal epithelial migration
3-oxo-C12-HSLIncreased migration at low concentrations (1.5-12 μmol/L) vs inhibition at 200 μmol/LKarlsson et al[72]
Interaction with IQGAP1 and increase in Rac1/Cdc42 (1.5-200 μmol/L)Karlsson et al[72]
Effects on the intestinal epithelial permeability and intercellular junctions
3-oxo-C12-HSLIncreased permeability to ions and macromolecules (100-400 μmol/L)Eum et al[55], Vikström et al[58-60], and Aguanno et al[61]
Activation of p38 and p42/44 and calcium signaling (100-200 μmol/L)Vikström et al[58-60]
Decreased expression levels of tight junction genes (100-400 μmol/L); Disassembly of tight and adherens junctions (modification of their phosphorylation status and involvement of MMP-2 and -3)Eum et al[55], Vikström et al[58-60], and Aguanno et al[61]
Decreased levels of tight junction proteins occludin and tricellulin (100-400 μmol/L)Eum et al[55]
Decreased protein levels of extracellular matrix and tight junction proteins (400 μmol/L)Tao et al[62]
3-oxo-C12:2-HSLNo deleterious effects on permeabilityProtection of tight junction integrity and maintenance of junctional complexes at the plasma membrane under pro-inflammatory conditionsLandman et al[39] and Aguanno et al[61]
3-oxo-C14-HSLDecreased protein levels of extracellular matrix and tight junction proteins (400 μmol/L)Tao et al[62]
Indole and indole derivativesDecreased permeability to ions and increased expression of genes coding tight junction and cytoskeleton proteinsBansal et al[76] and Shimada et al[77]
Decreased permeability to macromoleculesVenkatesh et al[79]
Increased transcripts levels of genes coding tight junction proteinsShin et al[78]
Effects on the mucus layer components
3-oxo-C12-HSLDecreased MUC3 mRNA levels (30 μmol/L)Taguchi et al[70]
Decrease in Muc2 production in goblet cell-like cell line (100 μmol/L) vs increase in colonic cell line (400 μmol/L)Tao et al[67]
IndoleIncreased expression of genes involved in the production of mucinsBansal et al[76]
Effects on intestinal epithelial cell viability
3-oxo-C12-HSLMitochondrial dysfunction and induction of apoptosis in goblet cell-like cell line (100 μmol/L) and in colonic cell line (30-100 μmol/L)Tao et al[67-69], and Taguchi et al[70]
Induction of apoptosis, mitochondrial dysfunction, oxidative stress and blocking of cell cycle (400 μmol/L)Tao et al[62]
3-oxo-C14-HSLInduction of apoptosis, mitochondrial dysfunction, oxidative stress and blocking of cell cycle (400 μmol/L)Eum et al[55], Vikström et al[58-60], Aguanno et al[61], and Tao et al[62]
CSFReduction of oxidative stress-induced cell death and loss of the epithelial barrier (involving HSP27 and p38/MAPK pathway)Fujiya et al[74]
Table 3 Effects of quorum sensing molecules on inflammation in different cell types
Cell type
QS molecule
Effects
Ref.
Effects on innate immune cells
Macrophages3-oxo-C12-HSLAnti-inflammatory effects on IL-12 and TNF-α (0.1-100 μmol/L)Telford et al[94]
Increased TLR2 and TLR4 expression and decreased TNF-α production (1-100 μmol/L)Bao et al[180]
Pro-apoptotic effects (12-50 μmol/L)Tateda et al[102]
Increased phagocytosis (100 μmol/L)Vikström et al[107]
NF-κB inhibition (4.7 μmol/L)Kravchenko et al[104]
Dose-dependent anti-inflammatory effects (1-50 μmol/L)Kravchenko et al[105]
Involvement in p38/MAPK signaling (1-100 μmol/L)Kravchenko et al[105], Vikström et al[107], Glucksam-Galnoy et al[181]
Activation of the Unfolded Protein Response (6.25-100 μmol/L)Zhang et al[182]
Change in cell volume and shape (10-50 μmol/L)Holm et al[183]
Indole derivativesPrevents the induction of pro-inflammatory cytokinesKrishnan et al[184]
AI-2Induction of the expression of cytokines, chemokines and TNFSF9Li et al[41]
MonocytesAI-3 and analoguesIncrease in IL-8 secretionKim et al[22]
Dendritic cells3-oxo-C12-HSLPro-apoptotic effects (100 μmol/L)Boontham et al[185]
No effect on IL-10 secretion (5-30 μmol/L)Skindersoe et al[100]
Increased IL-10 production (5-100 μmol/L)Li et al[99]
Decreased IL-12 secretion (5-100 μmol/L)Li et al[99] and Skindersoe et al[100]
Increased induction of Treg (5-100 μmol/L)Li et al[99]
Neutrophils3-oxo-C12-HSLChemoattraction (0.01-100 μmol/L)Karlsson et al[186] and Zimmermann et al[187]
Activation of MAPK signaling (12-50 μmol/L)Tateda et al[102] and Singh et al[188]
Increased phagocytosis (10 μmol/L)Wagner et al[189]
Pro-apoptotic effects (12-50 μmol/L)Tateda et al[102]
Effects on adaptive immune cells
T cells3-oxo-C12-HSLInhibition of proliferation and activation (0.1-100 μmol/L)Telford et al[94], Boontham et al[185], Gupta et al[190], and Hooi et al[191]
Activation of naïve T cells towards Th1 phenotype (5 μmol/L)Smith et al[95]
Decreased secretion of IL-4 and IFN-γ (5 μmol/L)Ritchie et al[96]
Induction of apoptosis via the mitochondria pathway (100 μmol/L)Jacobi et al[101]
Induction of Treg (1-50 μmol/L)Li et al[99]
Indole derivativesRe-programming into tolerogenic T cellsCervantes-Barragan et al[192]
Promotion of differentiation towards a regulatory type 1 phenotypeAoki et al[193]
B cells3-oxo-C12-HSLModulation of immunoglobulin production (0.1-100 μmol/L)Telford et al[94] and Ritchie et al[194]
ILCIndole derivativesPromotion of IL-22 productionZelante et al[83]
Effects on epithelial cells
Pulmonary tract epithelial cells3-oxo-C12-HSLInduction of IL-8 production and NF-B activation (100 μmol/L)Smith et al[195]
Increased expression levels of pro-inflammatory cytokinesJahoor et al[115]
Intestinal epithelial cells3-oxo-C12-HSLMitigation (1-10 μmol/L) or aggravation (> 50 μmol/L) of IL-8 expression inductionPeyrottes et al[92]
3-oxo-C12:2-HSLAttenuation of the induction of IL-8 expression (5-50 μmol/L)Landman et al[39]