title: Maturation Phenotype of Peripheral Blood Monocyte/Macrophage After Stimulation with Lipopolysaccharides in Irritable Bowel Syndrome.
abstract: OBJECTIVE
  Abnormal immune regulation and increased intestinal permeability augmenting the passage of bacterial molecules that can activate immune cells, such as monocytes/macrophages, have been reported in irritable bowel syndrome (IBS). The aim was to compare the maturation phenotype of monocytes/macrophages (CD14+) from IBS patients and controls in the presence or absence ofEscherichia colilipopolysaccharides (LPS), in vitro.
  
  
  METHODS
  Mononuclear cells were isolated from peripheral blood of 20 Rome II-IBS patients and 19 controls and cultured with or without LPS for 72 hours. The maturation phenotype was examined by flow cytometry as follows: M1-Early (CD11c+CD206-), M2-Advanced (CD11c-CD206+CX3CR1+); expression of membrane markers was reported as mean fluorescence intensity (MFI). The Mann-Whitney test was used and significance was set atP< 0.05.
  
  
  RESULTS
  In CD14+ cells, CD11c expression decreased with vs without LPS both in IBS (MFI: 8766.0 ± 730.2 vs 12 920.0 ± 949.2,P< 0.001) and controls (8233.0 ± 613.9 vs 13 750.0 ± 743.3,P< 0.001). M1-Early cells without LPS, showed lower CD11c expression in IBS than controls (MFI: 11 540.0 ± 537.5 vs 13 860.0 ± 893.7,P= 0.040), while both groups showed less CD11c in response to LPS (P< 0.01). Furthermore, the percentage of "Intermediate" (CD11c+CD206+CX3CR1+) cells without LPS, was higher in IBS than controls (IBS = 9.5 ± 1.5% vs C = 4.9 ± 1.4%,P< 0.001). Finally, fractalkine receptor (CX3CR1) expression on M2-Advanced cells was increased when treated with LPS in controls but not in IBS (P< 0.001).
  
  
  CONCLUSIONS
  The initial phase of monocyte/macrophage maturation appears to be more advanced in IBS compared to controls. However, the decreased CX3CR1 in patients with IBS, compared to controls, when stimulated with LPS suggests a state of immune activation in IBS.
authors.affiliation: Laboratorio de Hígado, Páncreas y Motilidad (HIPAM), Unidad de Investigación en Medicina Experimental, Facultad de Medicina-Universidad Nacional Autónoma de México (UNAM), Hospital General de México, Dr. Eduardo Liceaga, Mexico City, Mexico.|Dirección de Investigación, Fundación Universitaria-Unitrópico, Yopal, Colombia.
authors.forename: Oscar A
authors.initials: OA
authors.lastname: Rodríguez-Fandiño
authors.affiliation: Laboratorio de Hígado, Páncreas y Motilidad (HIPAM), Unidad de Investigación en Medicina Experimental, Facultad de Medicina-Universidad Nacional Autónoma de México (UNAM), Hospital General de México, Dr. Eduardo Liceaga, Mexico City, Mexico.
authors.forename: Joselín
authors.initials: J
authors.lastname: Hernández-Ruiz
authors.affiliation: Programa de Inmunología Molecular Microbiana, Departamento de Microbiología y Parasitología, Facultad de Medicina-Universidad Nacional Autónoma de México (UNAM), Mexico City, Mexico.
authors.forename: Yolanda
authors.initials: Y
authors.lastname: López-Vidal
authors.affiliation: Unidad de Coloproctología, Hospital General de México, Dr. Eduardo Liceaga, Mexico City, Mexico.
authors.forename: Luis
authors.initials: L
authors.lastname: Charúa-Guindic
authors.affiliation: Laboratorio de Hígado, Páncreas y Motilidad (HIPAM), Unidad de Investigación en Medicina Experimental, Facultad de Medicina-Universidad Nacional Autónoma de México (UNAM), Hospital General de México, Dr. Eduardo Liceaga, Mexico City, Mexico.
authors.forename: Galileo
authors.initials: G
authors.lastname: Escobedo
authors.affiliation: Laboratorio de Hígado, Páncreas y Motilidad (HIPAM), Unidad de Investigación en Medicina Experimental, Facultad de Medicina-Universidad Nacional Autónoma de México (UNAM), Hospital General de México, Dr. Eduardo Liceaga, Mexico City, Mexico.
authors.forename: Max J
authors.initials: MJ
authors.lastname: Schmulson
keywords: Fractalkine receptor; Irritable bowel syndrome; Lipopolysaccharides; Monocytes