Role of surfactant protein D (SP-D) in innate immunity in the gastric mucosa: evidence of interaction with Helicobacter pylori lipopolysaccharide.
Surfactant protein D (SP-D) is a collagenous glycoprotein, a collectin, which functions as a pathogen-associated molecular pattern (PAMP) recognition receptor in the innate immune response. Although originally identified in the lung as a component of surfactant, SP-D also occurs in the gastric mucosa at the luminal surface and within gastric pits of mucus-secreting cells. Infection with the gastroduodenal pathogen Helicobacter pylori up-regulates expression of SP-D in human patients with gastritis, and its influence on colonization has been demonstrated in a Helicobacter SP-D-deficient (SP-D(-/-)) mouse model. SP-D binds and agglutinates H. pylori cells in a lectin-specific manner, and has been shown to bind H. pylori lipopolysaccharide. Furthermore, evidence indicates that H. pylori varies LPS O-chain structure to evade SP-D binding which is speculated aids persistence of this chronic infection.
Moran
Anthony P
AP
Department of Microbiology, National University of Ireland, Galway, Ireland. anthony.moran@nuigalway.ie
Khamri
Wafa
W
Walker
Marjorie M
MM
Thursz
Mark R
MR
D005753:Gastric Mucosa / Q000276:immunology*; D005756:Gastritis / Q000276:immunology / Q000382:microbiology; D016480:Helicobacter pylori / Q000737:chemistry / Q000276:immunology*; D007113:Immunity, Innate; D008070:Lipopolysaccharides / Q000276:immunology*; D008954:Models, Biological; D037663:Pulmonary Surfactant-Associated Protein D / Q000276:immunology*
D008070:Lipopolysaccharides; D037663:Pulmonary Surfactant-Associated Protein D; C442865:lipopolysaccharide, Helicobacter pylori