Open AccessFilifactor alocis modulates human neutrophil antimicrobial functional responses
Author(s) -
Edmisson Jacob S.,
Tian Shifu,
Armstrong Cortney L.,
Vashishta Aruna,
Klaes Christopher K.,
Miralda Irina,
JimenezFlores Emeri,
Le Junyi,
Wang Qian,
Lamont Richard J.,
Uriarte Silvia M.
Publication year - 2018
Publication title -
cellular microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.542
H-Index - 138
eISSN - 1462-5822
pISSN - 1462-5814
DOI - 10.1111/cmi.12829
Subject(s) - medical school , medicine , oral medicine , library science , gerontology , family medicine , medical education , dentistry , computer science
Abstract Filifactor alocis is a newly appreciated pathogen in periodontal diseases. Neutrophils are the predominant innate immune cell in the gingival crevice. In this study, we examined modulation of human neutrophil antimicrobial functions by F. alocis . Both non‐opsonised and serum‐opsonised F. alocis were engulfed by neutrophils but were not efficiently eliminated. Challenge of neutrophils with either non‐opsonised or serum‐opsonised F. alocis induced a minimal intracellular as well as extracellular respiratory burst response compared to opsonised Staphylococcus aureus and fMLF, respectively. However, pretreatment or simultaneous challenge of neutrophils with F. alocis did not affect the subsequent oxidative response to a particulate stimulus, suggesting that the inability to trigger the respiratory response was only localised to F. alocis phagosomes. In addition, although neutrophils engulfed live or heat‐killed F. alocis with the same efficiency, heat‐killed F. alocis elicited a higher intracellular respiratory burst response compared to viable organisms, along with decreased surface expression of CD35, a marker of secretory vesicles. F. alocis phagosomes remained immature by delayed and reduced recruitment of specific and azurophil granules, respectively. These results suggest that F. alocis withstands neutrophil antimicrobial responses by preventing intracellular ROS production, along with specific and azurophil granule recruitment to the bacterial phagosome.