text: The septic abscess wall: a cytokine-generating organ associated with portal venous cytokinemia, hepatic outflow fibrosis, sinusoidal congestion, inflammatory cell sequestration, hepatocellular lipid deposition, and focal cell death.
  An acute septic inflammatory response with access to the portal circulation was created in a rat model using an intra-abdominal abscess composed of a sterile agar pellet, or one contaminated with 102 Escherichia coli (E. coli) and 109 Bacteriodes fragilis (B. fragilis). After 3 days postimplantation, a well-formed intra-abdominal abscess occurred whose wall showed IL-6 DNA by PCR and IL-6 mRNA by in situ hybridization. Portal venous blood draining into the liver from the intra-abdominal abscess had increased levels of TNF-alpha, IL-1beta, and IL-6 in both sterile and septic groups compared with a control normal animal group. Increased levels of these cytokines were also found in suprahepatic inferior vena caval blood, but were correlated with the higher portal vein levels, suggesting a gradient from abscess wall to portal vein into the systemic circulation via the liver. Liver histology demonstrated sinusoidal congestion centering on the central vein, growing worse with progression from normal in control, to sterile, to septic. Similarly, the degree of intrahepatic myeloperoxidase-positive inflammatory cell infiltration and hepatocellular lipid deposition and apoptosis also increased from control, to sterile, to septic. Gene expression by in situ hybridization demonstrated a significant increase in IL-6 and fibrinogen mRNAs in cells surrounding the central vein in sterile and septic animals, being greatest in animals with sepsis, associated with an increased deposition of collagen in the central vein area, most prominent in the septic liver. The pericentral vein cells with IL-6 and fibrinogen mRNA increases paralleled the increases in cells containing IL-6 and fibrinogen mRNAs in the abscess walls of sterile and septic animals, respectively. The data suggest that an intra-abdominal abscess, especially when contaminated with gram-negative bacteria, induces mRNA-generated cytokine responses in the abscess wall that are related to increased portal venous levels of the inflammatory cytokines TNF-alpha, IL-1beta, and IL-6 perfusing the liver. These, in turn, induce localized production of IL-6 and fibrinogen mRNAs in cells at the central vein area with resultant outflow fibrosis and increased inflammatory cell sequestration within the liver lobular sinuses. This is associated with a generalized inflammatory response and intrahepatic portal sinusoid congestion. There is also increased hepatocellular lipid deposition and apoptosis. Thus, the cytokine production of the abscess wall itself appears to be a major mediator of the septic hepatic response.
  
entities: ['organ']
entities: Organ
entities: PMID-12813373_T1
entities: ['portal venous']
entities: Multi-tissue_structure
entities: PMID-12813373_T2
entities: ['hepatic']
entities: Organ
entities: PMID-12813373_T3
entities: ['sinusoidal']
entities: Tissue
entities: PMID-12813373_T4
entities: ['inflammatory cell']
entities: Cell
entities: PMID-12813373_T5
entities: ['hepatocellular']
entities: Cell
entities: PMID-12813373_T6
entities: ['cell']
entities: Cell
entities: PMID-12813373_T7
entities: ['abdominal abscess']
entities: Pathological_formation
entities: PMID-12813373_T8
entities: ['abdominal abscess']
entities: Pathological_formation
entities: PMID-12813373_T9
entities: ['Portal venous blood']
entities: Organism_substance
entities: PMID-12813373_T10
entities: ['liver']
entities: Organ
entities: PMID-12813373_T11
entities: ['abdominal abscess']
entities: Pathological_formation
entities: PMID-12813373_T12
entities: ['suprahepatic inferior vena caval blood']
entities: Organism_substance
entities: PMID-12813373_T13
entities: ['portal vein']
entities: Multi-tissue_structure
entities: PMID-12813373_T14
entities: ['portal vein']
entities: Multi-tissue_structure
entities: PMID-12813373_T15
entities: ['liver']
entities: Organ
entities: PMID-12813373_T16
entities: ['Liver']
entities: Organ
entities: PMID-12813373_T17
entities: ['sinusoidal']
entities: Tissue
entities: PMID-12813373_T18
entities: ['central vein']
entities: Multi-tissue_structure
entities: PMID-12813373_T19
entities: ['inflammatory cell']
entities: Cell
entities: PMID-12813373_T20
entities: ['hepatocellular']
entities: Cell
entities: PMID-12813373_T21
entities: ['cells']
entities: Cell
entities: PMID-12813373_T22
entities: ['central vein']
entities: Multi-tissue_structure
entities: PMID-12813373_T23
entities: ['central vein']
entities: Multi-tissue_structure
entities: PMID-12813373_T24
entities: ['septic liver']
entities: Organ
entities: PMID-12813373_T25
entities: ['pericentral vein cells']
entities: Cell
entities: PMID-12813373_T26
entities: ['cells']
entities: Cell
entities: PMID-12813373_T27
entities: ['abscess walls']
entities: Multi-tissue_structure
entities: PMID-12813373_T28
entities: ['septic abscess wall']
entities: Multi-tissue_structure
entities: PMID-12813373_T29
entities: ['abscess wall']
entities: Multi-tissue_structure
entities: PMID-12813373_T30
entities: ['abdominal abscess']
entities: Pathological_formation
entities: PMID-12813373_T31
entities: ['abscess wall']
entities: Multi-tissue_structure
entities: PMID-12813373_T32
entities: ['portal venous']
entities: Multi-tissue_structure
entities: PMID-12813373_T33
entities: ['liver']
entities: Organ
entities: PMID-12813373_T34
entities: ['cells']
entities: Cell
entities: PMID-12813373_T35
entities: ['central vein']
entities: Multi-tissue_structure
entities: PMID-12813373_T36
entities: ['inflammatory cell']
entities: Cell
entities: PMID-12813373_T37
entities: ['abscess wall']
entities: Multi-tissue_structure
entities: PMID-12813373_T38
entities: ['liver lobular sinuses']
entities: Multi-tissue_structure
entities: PMID-12813373_T39
entities: ['septic hepatic']
entities: Organ
entities: PMID-12813373_T40
entities: ['hepatocellular']
entities: Cell
entities: PMID-12813373_T41
entities: ['wall']
entities: Tissue
entities: PMID-12813373_T42