Effects of C5a and FMLP on interleukin-8 production and proliferation of human umbilical vein endothelial cells.

Interleukin-8 (IL-8), C5a and N-formyl-methionyl-leucyl-phenylalanine (fMLP) are chemotactic peptides with predominant effects on leukocytes during inflammation. With emphasis on C5a we studied the regulation of the production of IL-8 by human umbilical vein endothelial cells (HUVEC) in vitro. Primary HUVEC cultures were incubated with IL-1alpha, TNFalpha, C5a and fMLP for 24 h and 48 h prior to measurement of IL-8 in supernatants of the cells by an enzyme immunoassay. Whereas IL-1alpha and TNFalpha significantly increased the levels of IL-8, C5a decreased the IL-8 production after 48 h. In addition, the ability of IL-1alpha, TNFalpha, C5a, fMLP and IL-8 to induce cell proliferation was compared by means of a 3H-thymidine incorporation assay. In contrast with IL-1alpha and TNFalpha, both C5a and fMLP increased cell proliferation of HUVEC. This increase occurred with increasing concentrations of C5a contrary to IL-8, which showed increased cell proliferation at low, but not high IL-8 concentrations.

Detection of mRNA for the terminal complement components C5, C6, C8 and C9 in human umbilical vein endothelial cells in vitro.

Human umbilical vein endothelial cells (HUVEC) have previously been shown to synthesize the functional terminal pathway of complement based on the detection by radioimmunoassay of the terminal complement complex (TCC) on coincubated agarose beads. In addition, C7 secretion by these cells in amounts comparable to C3, as well as C7 mRNA, has recently been demonstrated. However, it has not been possible to detect C5-6 and C8 in the fluid phase, and only trace amounts of soluble C9. Against this background we examined whether mRNA for the remaining terminal complement factors was present in HUVEC. By the use of reverse transcription (RT)-polymerase chain reaction (PCR) and Northern blot the presence of mRNA for complement factors C5, C6, C8 and C9 was demonstrated.

Elevated antibody responses in patients with Crohn's disease against a 14-kDa secreted protein purified from Mycobacterium avium subsp. paratuberculosis.

Patients with Crohn's disease (CD) (n = 10) and ulcerative colitis (UC) (n = 10) were tested for immune responses against various antigens from Mycobacterium avium subsp. paratuberculosis; alkyl hydroperoxide reductase C (AhpC) and alkyl hydroperoxide reductase D (AhpD), which are constitutively expressed in this species as opposed to other mycobacteria, a 14-kDa secreted antigen and PPD-J. The CD patients had significantly elevated antibody levels against the 14 kDa protein (P < 0.05) that were negatively correlated with the duration of the disease (r(s) = - 0.85). They also seemed to have increased antibody levels against AhpC and AhpD, but the differences between the two groups were not significant. However, taken together, the antibody responses to three individual mycobacterial antigens in CD patients strengthen the possibility that the observed responses are caused by mycobacterial infection. No significant differences in the interferon (IFN)-gamma production, the interleukin (IL)-10 production and the ability to proliferate upon stimulation with these antigens were observed. These results show that measuring antibody responses against purified specific antigens is a suitable and simple approach when assessing the connection between CD and mycobacteria in patients with clinical CD. Another important aspect in such studies is to have well defined patient groups tested at the onset of clinical symptoms.

The endothelium is an extrahepatic site of synthesis of the seventh component of the complement system.

The level of the terminal complement components secreted by human umbilical vein endothelial cells (HUVEC) was measured by a sensitive ELISA which allows the detection of 30-50 pg/ml of these components. C7 was the only terminal component detected in measurable amounts in the cell supernatant. The mean value was 11 ng/106 cells at 96 h and was slightly higher than that of C3 (9 ng/106 cells). HUVEC and serum C7 analysed by SDS-PAGE and immunoblot exhibited the same electrophoretic mobility. A proportion of C7 secreted by HUVEC was incorporated into the terminal complement complex (TCC) assembled spontaneously in the supernatant of cells cultured in C7-deficient human serum, and was not detected by the standard ELISA for C7 measurement. By adding the amount of C7 present in the TCC to that of free C7, the total amount of the component released by HUVEC was calculated to be approximately 35 ng/106 cells. Further TCC was produced following complement activation of the cell supernatant through the alternative pathway. Synthesis of C7 by HUVEC was confirmed by inhibition experiments in the presence of cycloheximide and by reverse transcriptase-polymerase chain reaction (RT-PCR) analysis of C7 mRNA expression. Addition of IL-1alpha and tumour necrosis factor-alpha to the cell culture stimulated the secretion of C3, but had no effect on the synthesis of C7. By contrast, interferon-gamma had only a marginal effect on the production of C3, but markedly down-regulated the synthesis of C7 as assessed both by ELISA and RT-PCR.

Concentrations of leucocyte-associated chemotaxin C5a correlate with the mobilisation of polymorphonuclear leucocytes during operations for rectal cancer.

OBJECTIVE: To describe the profile of potential chemotaxins C5a, interleukin 8 and tumour-necrosis factor alpha, and the peripheral blood leucocyte (PBL) response in five patients having uncomplicated operations for rectal cancer. DESIGN: Prospective study. SETTING: University hospital, Norway. SUBJECTS: Five patients, four men and one woman, median age 66 years (range 48-77) who were operated on for rectal cancer. INTERVENTION: Four had low anterior resections and total mesorectal excision (TME) and one patient had a diverting end sigmoidostomy because of local perirectal spread of the cancer and liver metastases. Blood samples were taken at the start of the operation; peroperatively after 1, 2, and 3 hours; postoperatively at 5, 8, and 24 hours, for analysis of potential chemotaxins. RESULTS: The number of PBL tripled between the start and end of the operation and declined to a slightly lower plateau between 5 and 24 hours. Peroperatively, the association of C5a with PBL increased six-fold resulting in a doubled concentration of C5a/PBL, whereas the corresponding concentration of C5a in plasma remained relatively constant. Postoperatively, the concentration of C5a associated with the PBL and in plasma fluctuated with the maximums being at 8 and 24 hours, respectively. In contrast to C5a in plasma, the concentration of cell-associated C5a correlated with number of PBL or polymorphonuclear leucocytes (PMN). The plasma concentration of IL-8 doubled during the operation, reached a six-fold maximum at 5 hours, and declined after 24 hours to twice the initial concentration. There were no correlations between plasma IL-8 and either number of PBL, plasma C5a, or PBL-associated C5a. No TNF alpha was detected in the plasma. CONCLUSION: Tissue trauma caused by uncomplicated excision of rectal cancer leads to leucocyte mobilisation peroperatively, probably partly by complement activation and subsequent generation and binding of the chemotaxin C5a to PBL. However, other chemotaxins may also play a role.

A population-based survey of biliary surgery in Norway. Relationship between patient volume and quality of surgical treatment.

BACKGROUND: A registry was initiated in order to establish national standards for the quality of surgical treatment of gallstones, and to provide feedback to all hospitals about serious complications, in order to reduce their future incidence. METHODS: Prospective registration of complications was performed at all hospitals and collected in the National Norwegian Cholecystectomy Registry (NNCR) over a period of 33 months. RESULTS: Open cholecystectomy (OC) was performed in 1011 patients, and laparoscopic cholecystectomy (LC) in 4332 patients. These figures represent 68% of all procedures performed nationally. The frequency of bile duct (BD) injury was 0. 8% for LC versus 0.7% for OC (ns); mortality was 0.1% versus 2.1%, respectively (p < 0.05). The frequency of BD injury and mortality were added; the sum comprised the Severe Complication Index (SCI). A linear relationship was found between SCI and patient volume (correlation coefficient, r22 = 0.78). CONCLUSIONS: SCI was found to be the best indicator of surgical success. We have proposed its use as a parameter for a future prospective quality assurance program, along with patient volume.