Colitogenic Bacteroides thetaiotaomicron Antigens Access Host Immune Cells in a Sulfatase-Dependent Manner via Outer Membrane Vesicles

• Microbes interact with the host immune system via several potential mechanisms. One essential step for each mechanismis themethod by which intestinal microbes or their antigens access specific host immune cells. Using genetically susceptible mice (dnKO) that develop spontaneous, fulminant colitis, triggered by Bacteroides thetaiotaomicron (B. theta), we investigated the mechanism of intestinal microbial access under conditions that stimulate colonic inflammation. B. theta antigens localized to host immune cells through outer membrane vesicles (OMVs) that harbor bacterial sulfatase activity. We deleted the anaerobic sulfatase maturating enzyme (anSME) from B. theta, which is required for post-translational activation of all B. theta sulfatase enzymes. This bacterial mutant strain did not stimulate colitis in dnKO mice. Lastly, access of B. theta OMVs to host immune cells was sulfatase dependent. These data demonstrate that bacterial OMVs and associated enzymes promote inflammatoryimmune stimulation in genetically susceptible hosts.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinska och farmaceutiska grundvetenskaper -- Mikrobiologi inom det medicinska området (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Basic Medicine -- Microbiology in the medical area (hsv//eng)

Keyword

INFLAMMATORY-BOWEL-DISEASE

HUMAN GUT SYMBIONT

MUC2 MUCIN

BACTERIAL

SYMBIONT

SMALL-INTESTINE

COMMENSAL

COLON

MACROPHAGES

COLITIS

PURIFICATION

Microbiology

Parasitology

Virology

Publication and Content Type

ref (subject category)

art (subject category)