TY - JOUR
T1 - Streptococcus gordonii-Induced miRNAs Regulate CCL20 Responses in Human Oral Epithelial Cells
AU - Alves, Vanessa Tubero Euzebio
AU - Al-Attar, Ahmad
AU - Alimova, Yelena
AU - Maynard, Marshall H.
AU - Kirakodu, Sreenatha
AU - Martinez-Porras, Andrés
AU - Hawk, Gregory S.
AU - Ebersole, Jeffrey L.
AU - Stamm, Stefan
AU - Gonzalez, Octavio A.
N1 - Publisher Copyright:
Copyright © 2022 American Society for Microbiology. All Rights Reserved.
PY - 2022/3
Y1 - 2022/3
N2 - The mechanisms through which oral commensal bacteria mitigates uncontrolled inflammatory responses of the oral mucosa remain unknown. Here, we show that representative oral bacterial species normally associated with oral health [S. gordonii (Sg), V. parvula (Vp), A. naeslundii (An), C. sputigena (Cs), and N. mucosa (Nm)] enhanced differential chemokine responses in oral epithelial cells (OECs), with some bacteria (An, Vp, and Nm) inducing higher chemokine levels (CXCL1, CXCL8) than others (Sg, Cs). Although all bacterial species (except Cs) increased CCL20 mRNA levels consistent with protein elevations in cell lysates, only An, Vp, and Nm induced higher CCL20 secretion, similar to the effect of the oral pathogen F. nucleatum (Fn). In contrast, most CCL20 remained associated with OECs exposed to Sg and negligible amounts released into the cell supernatants. Consistently, Sg attenuated An-induced CCL20. MiR-4516 and miR-663a were identified as Sg-specifically induced miRNAs modulating validated targets of chemokine-associated pathways. Cell transfection with miR-4516 and miR-663a decreased An-@@@@@and Fn-induced CCL20. MiRNA upregulation and attenuation of An-induced CCL20 by Sg were reversed by catalase. Up-regulation of both miRNAs was specifically enhanced by oral streptococci H2O2producers. These findings suggest that CCL20 levels produced by OECs in response to bacterial challenge are regulated by Sg-induced miR-4516 and miR-663a in a mechanism that involves hydrogen peroxide. This type of molecular mechanism could partly explain the central role of specific oral streptococcal species in balancing inflammatory and antimicrobial responses given the critical role of CCL20 in innate (antimicrobial) and adaptive immunity (modulates Th17 responses).
AB - The mechanisms through which oral commensal bacteria mitigates uncontrolled inflammatory responses of the oral mucosa remain unknown. Here, we show that representative oral bacterial species normally associated with oral health [S. gordonii (Sg), V. parvula (Vp), A. naeslundii (An), C. sputigena (Cs), and N. mucosa (Nm)] enhanced differential chemokine responses in oral epithelial cells (OECs), with some bacteria (An, Vp, and Nm) inducing higher chemokine levels (CXCL1, CXCL8) than others (Sg, Cs). Although all bacterial species (except Cs) increased CCL20 mRNA levels consistent with protein elevations in cell lysates, only An, Vp, and Nm induced higher CCL20 secretion, similar to the effect of the oral pathogen F. nucleatum (Fn). In contrast, most CCL20 remained associated with OECs exposed to Sg and negligible amounts released into the cell supernatants. Consistently, Sg attenuated An-induced CCL20. MiR-4516 and miR-663a were identified as Sg-specifically induced miRNAs modulating validated targets of chemokine-associated pathways. Cell transfection with miR-4516 and miR-663a decreased An-@@@@@and Fn-induced CCL20. MiRNA upregulation and attenuation of An-induced CCL20 by Sg were reversed by catalase. Up-regulation of both miRNAs was specifically enhanced by oral streptococci H2O2producers. These findings suggest that CCL20 levels produced by OECs in response to bacterial challenge are regulated by Sg-induced miR-4516 and miR-663a in a mechanism that involves hydrogen peroxide. This type of molecular mechanism could partly explain the central role of specific oral streptococcal species in balancing inflammatory and antimicrobial responses given the critical role of CCL20 in innate (antimicrobial) and adaptive immunity (modulates Th17 responses).
KW - CCL20
KW - Chemokine regulation
KW - Hydrogen peroxide
KW - MiRNA
KW - Oral commensal bacteria
KW - Oral epithelial cells
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UR - http://www.scopus.com/inward/citedby.url?scp=85126996406&partnerID=8YFLogxK
U2 - 10.1128/iai.00586-21
DO - 10.1128/iai.00586-21
M3 - Article
C2 - 35099275
AN - SCOPUS:85126996406
SN - 0019-9567
VL - 90
JO - Infection and Immunity
JF - Infection and Immunity
IS - 3
M1 - e00586-21
ER -