Patient-derived fibroblasts indicate oxidative stress status and may justify antioxidant therapy in OXPHOS disorders.

Oxidative phosphorylation disorders are often associated with increased oxidative stress and antioxidant therapy is frequently given as treatment. However, the role of oxidative stress in oxidative phosphorylation disorders or patients is far from clear and consequently the preventive or therapeutic effect of antioxidants is highly anecdotic. Therefore, we performed a systematic study of a panel of oxidative stress parameters (reactive oxygen species levels, damage and defense) in fibroblasts of twelve well-characterized oxidative phosphorylation patients with a defect in the POLG1 gene, in the mitochondrial DNA-encoded tRNA-Leu gene (m.3243A>G or m.3302A>G) and in one of the mitochondrial DNA-encoded NADH dehydrogenase complex I (CI) subunits. All except two cell lines (one POLG1 and one tRNA-Leu) showed increased reactive oxygen species levels compared with controls, but only four (two CI and two tRNA-Leu) cell lines provided evidence for increased oxidative protein damage. The absence of a correlation between reactive oxygen species levels and oxidative protein damage implies differences in damage prevention or correction. This was investigated by gene expression studies, which showed adaptive and compensating changes involving antioxidants and the unfolded protein response, especially in the POLG1 group. This study indicated that patients display individual responses and that detailed analysis of fibroblasts enables the identification of patients that potentially benefit from antioxidant therapy. Furthermore, the fibroblast model can also be used to search for and test novel, more specific antioxidants or explore ways to stimulate compensatory mechanisms.

Evaluation of a group-specific 16S ribosomal DNA-based PCR for detection of Helicobacter bizzozeronii, Helicobacter felis, and Helicobacter salomonis in fresh and paraffin-embedded gastric biopsy specimens.

A new specific and sensitive 16S ribosomal DNA-based PCR assay was developed. The assay targets a 78-bp DNA fragment unique to Helicobacter bizzozeronii, Helicobacter felis, and Helicobacter salomonis and can be used with freshly frozen and formalin-fixed paraffin-embedded gastric biopsy specimens.

Increased synovial fluid levels of interleukin-12, sCD25 and sTNF-RII/sTNF-RI ratio delineate a cytokine pattern characteristic of immune arthropathies.

The assessment of cytokines and their soluble receptors in the synovial fluid (SF) of inflammatory arthropathies may be useful in studying pathogenetic and immunoregulatory mechanisms underlying different diseases. The aim of this work was to study the cytokine network occurring in inflammatory arthropathies and to identify a cytokine profile which is characteristic of an immune-mediated synovitis. Levels of IL-12, as well as IL-4, IL-8, IL-10, IFN-gamma, sCD25, TNF-alpha and its soluble receptors were measured in the SF of various arthropathies, i.e. non-inflammatory arthropathies: "control" meniscus pathology (n = 21), osteoarthritis (n = 22) and chronic crystal arthritis (n = 9); a non-immune inflammatory arthropathy: acute crystal arthritis (n = 11); 2 immune inflammatory arthropathies: reactive arthritis (ReA) (n = 23) and rheumatoid arthritis (RA) (n = 44). SF levels of IL-10, TNF-alpha and sTNF-RII were found to be increased in the three inflammatory arthropathies compared to the "control" meniscus group. Within the inflammatory group, acute crystal arthritis was characterized by a significantly higher sTNF-RI/TNF-alpha ratio and ReA by a significantly lower sTNF-RII/TNF-alpha ratio compared to the two other diseases. The two immune arthropathies, RA and ReA, were characterized by increased SF levels of IL-12, sCD25 and of the sTNF-RII/sTNF-RI ratio. ReA differed however from RA by showing lower IL-8 and IL-4 levels, higher IFN-gamma levels and a higher IL-12/IL-10 ratio, suggesting a more prevalent Th1 profile in ReA SF. Our data indicate that the measurement of SF cytokines and soluble receptors may discriminate between each inflammatory arthropathy and might be useful in clinical practice.

Cytokine production from peripheral whole blood in atopic and nonatopic asthmatics: relationship with blood and sputum eosinophilia and serum IgE levels.

BACKGROUND: The cytokine network is thought to be essential in orchestrating airway inflammation in asthma. Although evidence has accumulated to suggest that atopic asthma is a Th2 disease, much less is known about nonatopic asthma. METHODS: We have compared the production of IL-4, IL-6, IFN-gamma, and TNF-alpha from peripheral blood leukocytes between atopic (n=21) and nonatopic (n=22) asthmatics and healthy nonatopic subjects (n=20). Peripheral blood was incubated for 24 h either without stimulus or with LPS or PHA. Cytokines were measured by the immunotrapping technique (Dynamic Immunoassay). RESULTS: When compared to healthy nonatopic subjects, both atopic and nonatopic asthmatics showed increased blood and sputum eosinophilia associated with raised total serum IgE levels. Similarly, both asthma groups displayed spontaneous, endotoxin-induced overproduction of IL-6. Enhanced spontaneous, endotoxin-induced release of IL-4 combined with reduced spontaneous IFN-gamma production was seen only in atopic asthma. In this group of patients, the production of IL-4 was related to the extent of blood and sputum eosinophilia. In nonatopic asthmatics, serum levels of IgE were inversely related to the production of IFN-gamma. CONCLUSIONS: Both atopic and intrinsic asthma display raised blood and airway eosinophilia, raised total serum IgE, and overproduction of IL-6 from peripheral blood. Atopic asthma is also characterized by impaired spontaneous release of IFN-gamma and increased production of IL-4 that correlates with the magnitude of eosinophilic inflammation.

Increased production of matrix metalloproteinase-3 and tissue inhibitor of metalloproteinase-1 by inflamed mucosa in inflammatory bowel disease.

Inflammatory bowel diseases (IBD) are characterized by a sustained inflammatory cascade that gives rise to the release of mediators capable of degrading and modifying bowel wall structure. Our aims were (i) to measure the production of matrix metalloproteinase-3 (MMP-3), and its tissue inhibitor, tissue inhibitor of metalloproteinase-1 (TIMP-1), by inflamed and uninflamed colonic mucosa in IBD, and (ii) to correlate their production with that of proinflammatory cytokines and the anti-inflammatory cytokine, IL-10. Thirty-eight patients with IBD, including 25 with Crohn's disease and 13 with ulcerative colitis, were included. Ten controls were also studied. Biopsies were taken from inflamed and uninflamed regions and inflammation was graded both macroscopically and histologically. Organ cultures were performed for 18 h. Tumour necrosis factor-alpha (TNF-alpha), IL-6, IL-1beta, IL-10, MMP-3 and TIMP-1 concentrations were measured using specific immunoassays. The production of both MMP-3 and the TIMP-1 were either undetectable or below the sensitivity of our immunoassay in the vast majority of uninflamed samples either from controls or from those with Crohn's disease or ulcerative colitis. In inflamed mucosa, the production of these mediators increased significantly both in Crohn's disease (P < 0.01 and 0.001, respectively) and ulcerative colitis (P < 0.001 and 0.001, respectively). Mediator production in both cases was significantly correlated with the production of proinflammatory cytokines and IL-10, as well as with the degree of macroscopic and microscopic inflammation. Inflamed mucosa of both Crohn's disease and ulcerative colitis show increased production of both MMP-3 and its tissue inhibitor, which correlates very well with production of IL-1beta, IL-6, TNF-alpha and IL-10.

Matrix metalloproteinase-3 serum levels are correlated with disease activity and predict clinical response in rheumatoid arthritis.

OBJECTIVE: To demonstrate that serum matrix metalloproteinase-3 (MMP-3) is a variable associated with disease activity and with the response to treatment in rheumatoid arthritis (RA). METHODS: Serum MMP-3 levels were measured and compared to biological and clinical disease activity variables in 20 patients with active RA assessed serially during a one year prospective open label trial with methotrexate or tenidap. RESULTS: MMP-3 levels were significantly correlated with C-reactive protein (CRP) and interleukin 6 serum levels as well as with the disease activity score (DAS), not only at start in untreated patients but also during the 12 month followup period in both treated groups. Early changes (after 0.5, 1, 2, or 3 months) in MMP-3 levels were significantly associated with change in DAS observed 4 to 6 months later. CONCLUSION: In addition to CRP, a systemic marker of inflammation, serum MMP-3 may serve as a consistent synovial derived marker of RA disease activity, early changes of which predict disease outcome.

Increased synovial fluid levels of soluble CD23 are associated with an erosive status in rheumatoid arthritis (RA).

Synovial fluid (SF) levels of soluble CD23 (sCD23) were determined in 96 patients presenting with an inflammatory knee effusion (73 with RA and 23 with reactive arthritis (ReA) serving as a control inflammatory non-erosive group) and were correlated with the degree of joint destruction, with local immune parameters (IL-1beta, IL-3, IL-4, IL-6, IL-8, IL-10, IL-12 and sCD25) and with serum markers of inflammation, C-reactive protein and erythrocyte sedimentation rate. RA patients, classified as erosive or not according to Larsen's grade, were separated as follows: (i) 13 patients with non-erosive RA; (ii) 16 RA patients with erosions in hands but not in knees, matched for disease duration with the first group; (iii) 44 RA patients with hand and knee erosions, matched with the second group for rheumatoid factor positivity but of longer disease duration. SF sCD23 levels were significantly increased in both erosive RA groups compared with non-erosive diseases, whether RA or ReA (P < 0.05), whose SF levels were not different. SF IL-10 showed a similar profile to that of SF sCD23 and was the only other parameter characteristic of erosive RA, but no direct correlation was found between the two. SF sCD23 was significantly correlated with IL-12 (r = 0.65, P = 0.0001) and sCD25 (r = 0.39, P = 0.0019) exclusively in the two erosive RA populations. In conclusion, these data showing that increased levels of sCD23 are not only found in the SF of erosive joints but also in knee SF of patients with erosive RA but without knee x-ray-diagnosed erosions suggest that this parameter might be of predictive value for joint destruction. Longitudinal studies are however needed to confirm its potential clinical interest.

Detection of "Candidatus Helicobacter suis" in gastric samples of pigs by PCR: comparison with other invasive diagnostic techniques.

Recently, a new 16S ribosomal DNA-based PCR assay was developed for the specific detection of "Candidatus Helicobacter suis" (former "Gastrospirillum suis") in porcine gastric samples. In the present study, this PCR assay was compared to three other invasive diagnostic methods (rapid urease test, immunohistochemistry, histologic analysis by Giemsa staining). Antral stomach samples from 200 slaughterhouse pigs from Belgium and The Netherlands were examined. Bacterial presence was determined in 77% (154 of 200) of the samples by PCR in combination with Southern blot hybridization, 56% (111 of 200) of the samples by immunohistochemistry, 61% (122 of 200) of the samples by urease testing (20 h postinoculation [p.i.]), 36% (71 of 200) of the samples by urease testing (3 h p.i.), and 33% (65 of 200) of the samples by Giemsa staining. The intrinsic specificity of the PCR assay was assessed by Southern blot analysis with an "Candidatus H. suis"-specific probe and sequencing of PCR products. Interassay sensitivity and specificity values were assessed for each test by pairwise comparisons between tests. Agreement between tests was evaluated by calculating Cohen's kappa coefficient. From that analysis, the PCR assay was considered the most reliable benchmark. Microscopic detection of immunohistochemically labeled or Giemsa-stained "Candidatus H. suis" cells in stomach sections proved to be highly specific (100%) but relatively insensitive (72 and 42%, respectively) compared to the PCR assay. A longer incubation time of the urease test improved its sensitivity considerably (74 versus 55%) but was accompanied by a loss of specificity (72 versus 93%). In conclusion, we found the "Candidatus H. suis"-specific PCR assay to be a sensitive and reliable diagnostic method for the detection of "Candidatus H. suis" in the stomachs of pigs and could prove to be a valuable tool for further epidemiological studies both for "Candidatus H. suis"- and for "Helicobacter heilmannii" type 1-related research.

Ex vivo interferon-gamma response to human immunodefiency virus-1 derived peptides in human immunodeficiency virus-1 infected patients.

The pattern of human immunodeficiency virus (HIV)-1 antigen-activated production of interferon (IFN)-gamma by immunocompetent cells of HIV-1 infected patients has been studied using a simplified assay combining a small volume (25 microliter) of whole blood stimulation with various HIV-1 antigens, and cytokine measurement in the same wells of microtitre plates (enzyme-linked immunotrapping assay, ELITA). The levels of IFN-gamma were higher using this assay than in the supernatant from stimulated whole blood cultures, therefore ELITA was used in the rest of the study. Specific immune responses to HIV-1 proteins (gp120, p24) and synthetic peptides derived from these proteins and from gp41 were detected in patients, but not in healthy controls. Decreased levels of IFN-gamma were observed in CDC class B (n = 5) and C (n = 4), compared with CDC class A (n = 5), following HIV-1 antigen-specific challenge. The positive response of cells from different patients to overlapping peptides of p25 (amino acids 329-344 and 335-351) was suggestive of a new epitope of HIV-1 gag recognized by T cells in the overlap region. In conclusion, the difference in in vitro antigen-specific T-cell responses of HIV-1-infected patients was shown using the ELITA method. Our results raise the possibility of using this method in screening specific antigens in HIV-1 infection.