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H Repo

Publications and source records attributed to H Repo.

At least 19 recordsLinked to original sources
PubMed1996

Heterogeneity of rearranged T cell receptor V alpha and V beta gene transcripts in synovial fluid T cells of HLA-B27 positive reactive arthritis patients.

To analyze the T cell receptor (TCR) V-alpha/beta gene usage by synovial fluid (SF) and peripheral blood (PB) T cells of HLA-B27+ reactive arthritis (ReA) patients. The TCR V-alpha/beta gene usage was determined by the polymerase chain reaction on freshly isolated SF and PB mononuclear cells (MNC) of five HLA-B27+ ReA patients. A total of 30 TCR V alpha and 23 V beta (sub)family specific primers in combination with a C alpha or C beta specific primer, respectively, were used. In five patients most of the TCR V alpha and V beta gene segments expressed by PB T cells were also detected in the paired SF samples. Although one patient showed an increased expression of TCR V alpha2 in SF when compared to PB, the SF samples showed a heterogeneous TCR V-gene repertoire similar to PB. Although this study was limited to a small group of patients, the apparent lack of a restricted TCR V-gene repertoire in SF does not support the involvement of a single or limited number of T cell subsets in the disease process of HLA-B27+ ReA patients.

Adult↗
PubMed1996

Standardization of a flow cytometric assay for phagocyte respiratory burst activity.

The authors optimized the flow cytometric dichlorofluorescin (DCFH)-oxidation assay for buffy coat neutrophil and monocyte respiratory burst activity. Sample handlings were minimized, monocytes identified with a CD14 antibody, and viability evaluated with propidium iodide. Sodium citrate was a better anticoagulant than heparin, with a more intense Yersinia enterocolitica (YER)-induced dichlorofluorescein (DCF)-fluorescence intensity and a higher proportion of DCF-positive cells. EDTA was unsuitable as an anticoagulant with reduced cell viability and poor DCF response. Exposure of cells to YER, phorbol myristate acetate (PMA) or N-formyl-methionyl-leucyl-phenylalanine (FMLP) elicited two neutrophil subpopulations, one with low and the other with high forward light scattering properties. FMLP induced only a marginal DCF response, but after YER or PMA, virtually all neutrophils responded with an increased DCF production. During optimal conditions, the resulting DCF- fluorescence histogram was two-peaked, and the subset of cells with increased forward light scattering properties corresponded to the cells with intense DCF-fluorescence. A similar heterogeneity was frequently but not always observed amongst monocytes. The results indicate that in the peripheral blood there are at least two neutrophil and monocyte populations. One is an effective responder to stimuli, the other exhibiting a moderate response only. Properly optimized, the DCFH-oxidation assay may be used for evaluating neutrophil and monocyte subsets in a clinical setting.

Adult↗
PubMed1996

Chemiluminescence responses and chemotaxis of monocytes from patients with early rheumatoid arthritis.

We studied chemiluminescence (CL) responses and chemotaxis of monocytes of patients with early rheumatoid arthritis (RA) before starting anti-rheumatic drug treatment and correlated the data to 2-year prognosis of the patients. Luminol-enhanced CL responses of RA monocytes to N-formylmethionyl-leucyl-phenylalanine or to phorbol myristate acetate, and lucigenin-enhanced responses to opsonized zymosan particles were significantly higher than those of healthy control subjects. Distances of chemotactic, chemokinetic and random migration of RA monocytes were similar to those of control cells. High CL responsiveness correlated with seropositivity but not with presence of HLA-DR4 or that of erosions at 2-year follow-up. The results give credence to the view that monocytes are metabolically activated in early untreated RA, but increased respiratory burst activity does not predict early development of erosions.

Adult↗
PubMed1996

Time course of beta 2-integrin CD11b/CD18 (Mac-1, alpha M beta 2) upregulation on neutrophils and monocytes after coronary artery bypass grafting. CD11b upregulation after CABG surgery.

Although upregulation of CD11b/CD18 receptor, i.e. activation of neutrophils and monocytes, during cardiopulmonary bypass is well documented, the duration of the active state after uncomplicated operation is less understood. We therefore investigated CD11b expression of phagocytes in blood samples collected 2-4, 24, 48 and 72 h after coronary artery bypass grafting. CD11b expression on neutrophils was significantly elevated at 2-4 and 24 hours after operation as compared with baseline. On monocytes, expression peaked at 24 h and returned to baseline by 72 h. Because CD11b is a sensitive marker, effects of different sampling techniques on its expression were also studied. CD11b expression was similar in samples collected with a syringe from arterial or central venous catheter or with open technique from cubital vein. On neutrophils from healthy subjects, sampling with syringe caused small (10%) but statistically significant increase of expression. We conclude that activated neutrophils disappear from circulation within hours after CABG surgery while activated monocytes may continue circulating for 2-3 days, and that CD11b sampling can be done with a syringe.

CD18 Antigens↗
PubMed1995

Anticoagulant selection influences flow cytometric determination of CD11b upregulation in vivo and ex vivo.

We recently devised three-colour flow cytometric assay for evaluating expression of CD11b on neutrophils and monocytes in circulation. Artefactual upregulation of CD11b ex vivo was minimized by cooling blood samples on ice. In this communication we further characterize the method in terms of different anticoagulants. EDTA was less optimal than ACD or heparin because (i) saturating concentrations of CD11b antibody (clone D12) were not achieved with resting cells; (ii) CD11b fluorescence intensity of synovial fluid cells, i.e., in vivo activated cells expressing CD11b at high levels, was significantly lower in EDTA plasma, and (iii) EDTA mediated more cell damage at 37 degrees C, as determined by PI staining. The fluorescence data suggested that D12 antibody binding was dependent on divalent cations. Saturating concentrations in the presence of EDTA in medium were easily obtained with synovial fluid cells and peripheral blood phagocytes activated with chemotactic peptide FMLP, suggesting that cell activation decreased cation concentrations required for D12 antibody binding. Using another CD11b antibody (2MPL19c), whose binding proved to be cation independent, it was shown that CD11b upregulation was not affected by EDTA. ACD was superior to heparin and phenylalanylprolylarginyl chloromethyl ketone (PPACK), a thrombin inhibitor, because cell counts were significantly lower in heparinized samples in cold, and in PPACK-anticoagulated samples treated with LPS at 37 degrees C. Kinetics of L-selectin shedding was similar in heparin and ACD, suggesting that cell loss did not derive from differences in cell activation. In comparison of buffy coat cell assay and whole blood assay, neutrophil CD11b expression was similar but background fluorescence was significantly higher in whole blood preparations. This implies that nonspecific antibody binding may occur more in whole blood assay, whereas in the buffy coat cell assay, sample manipulation procedures may slightly increase CD11b antibody binding, but not control antibody binding. Finally, it was confirmed that warming from 0 degrees C, but not from room temperature, to 37 degrees C increased CD11b expression significantly on neutrophils, and it was further shown that monocytes undergo similar changes. Cooling did not upregulate CD11b, and completely prevented LPS-induced upregulation. In conclusion, the results support use of ACD in evaluating CD11b expression; if EDTA is used, it is important to make sure that binding of CD11b antibody selected does not require presence of divalent cations in medium.

Adult↗
PubMed1995

Inhaled recombinant interferon gamma in patients with lung cancer: pharmacokinetics and effects on chemiluminescence responses of alveolar macrophages and peripheral blood neutrophils and monocytes.

PURPOSE: A Phase I trial was conducted to investigate clinical toxicity, pharmacokinetics, and chemiluminescence (CL) responses of alveolar macrophages (AM) and peripheral blood neutrophils and monocytes after inhalation of recombinant interferon (r IFN)-gamma. METHODS AND MATERIALS: Eight patients with lung cancer inhaled r IFN-gamma as single doses of 0.1, 0.2, 0.6, 1.8, or 5.4 mg. Bronchoalveolar lavage was performed three times, 21 h before as well as 3 and 27 h after inhalation. RESULTS: Interferon-gamma was detectable in bronchoalveolar lavage fluid (BALF) samples taken 3 h after inhalation in doses of > or = 0.6 mg. Before inhalation, AM in four out of seven patients studied showed vigorous lucigenin-enhanced CL responses to N-formyl-methionyl-leucyl-phenylalanine and opsonized zymosan particles. Furthermore, the responses were markedly increased 3 h after inhalation. In three out of seven patients, AM in the pretreatment BALF samples showed low or no CL responses, and the responses did not increase after inhalation of IFN-gamma, suggesting that the patients were anergic. Postinhalation CL responses did not correlate with the dose of IFN-gamma inhaled. Circulating IFN-gamma was detected in one patient receiving the highest dose. No changes referable to IFN-gamma inhalation were found in the CL responses of blood neutrophils and monocytes. During the 24 h follow-up, two patients developed transient fever-reactions. CONCLUSIONS: The findings suggest that inhalation may provide a way to increase alveolar concentrations of IFN-gamma and to augment respiratory burst capacity of AM without any major side effects. This approach may have clinical implications for the treatment of tumors and infections of the respiratory tract.

Adult↗
PubMed1995

Production of TNF by monocytes of patients with early rheumatoid arthritis is increased.

We studied the production of tumour necrosis factor alpha (TNF) by monocytes of patients with early rheumatoid arthritis (RA) before starting disease modifying anti-rheumatic drug treatment and a median 6 months (range 5-11 months) later, and correlated the pre-treatment results with 3-year prognosis. Monocytes of patients (n = 14) and controls (n = 14), isolated by the density gradient centrifugations, were cultured for 24 h with Escherichia coli lipopolysaccharide (LPS) 0-10 micrograms/ml. Before treatment, levels of TNF were higher in LPS-stimulated RA monocyte cultures than in the control cultures; differences were statistically significant in LPS 10 and 0.01 micrograms/ml. At 6 months, respective differences were not significant. Levels of TNF before treatment did not correlate to clinical or laboratory parameters of inflammation, or development of erosions. The results indicate that monocytes of patients with early RA are primed, and that the state of priming decreases during treatment.

Adult↗
PubMed1994

Alkali-treated LPS of Yersinia enterocolitica does not induce expression of E-selectin, ICAM-1 or VCAM-1 on endothelial cells but may mediate antibody- and complement-dependent cell injury.

Lipopolysaccharide (LPS) prepared from a rough mutant of Salmonella typhimurium and deacylated enzymatically (dLPS) does not promote neutrophil adherence to human umbilical vein endothelial cells (HUVECs). This paper reports that similarly, a smooth form of LPS prepared from Yersinia enterocolitica O:3, a serotype known to trigger reactive arthritis in humans, and treated with alkali (yersinia LPS-OH) failed to augment neutrophil adherence to HUVECs. Studies of the mechanism underlying the poor augmentation revealed that neither enzymatically deacylated LPS from Escherichia coli J5 (J5 dLPS) nor yersinia LPS-OH stimulated expression of endothelial cell adhesion molecules E-selectin, VCAM-1 and ICAM-1, whereas both intact J5 LPS and yersinia LPS were stimulatory. Impaired up-regulation could not be explained by decreased binding of yersinia LPS-OH to HUVECs. Furthermore, 51Cr-labelled HUVECs treated with different concentrations of yersinia LPS-OH released 51Cr in the presence of anti-yersinia anti-O antibody and complement. J5 dLPS and yersinia LPS-OH inhibited up-regulation of the adhesion molecules induced by J5 LPS and yersinia LPS but not that induced by tumour necrosis factor alpha. Taken together, the results suggest that although yersinia LPS-OH can depress development of acute inflammation by inhibiting up-regulation of endothelial-cell adhesion molecules, sufficient LPS-OH is bound to induce cell injury and thereby inflammation in the presence of specific antibody and complement. The findings may have pathogenetic implications in yersinia-triggered reactive arthritis characterized by dissemination of yersinia LPS throughout the body.

ABO Blood-Group System↗
PubMed1994

Reactive oxygen species of neutrophils from patients with monosomy 7 in the bone marrow: contradictory chemiluminescence activity by whole blood or by purified cells.

Monosomy 7, a deletion of the long arm of chromosome 7, was shown in the neutrophils of peripheral blood in 5 of 6 patients with a myelodysplastic syndrome or leukemia who had monosomy 7 in their bone marrow cells. In a chemiluminescence assay the production of reactive oxygen species by neutrophils from patients was increased in whole blood and decreased in purified cells, which suggests that neutrophils with monosomy 7 tolerate poorly the cell purification procedures used. The in vitro migration of purified neutrophils obtained from patients with monosomy 7 was impaired. It is known that patients with monosomy 7 have an increased susceptibility to infections. It is possible that neutrophils with monosomy 7 are too easily triggered to a full-scale respiratory burst and thereby the cells exhaust their ability to eliminate invading microbes efficiently.

Adult↗
PubMed1994

Subcutaneously administered recombinant interferon-gamma in humans: pharmacokinetics and effects on chemiluminescence responses of alveolar macrophages, blood neutrophils, and monocytes.

A Phase I trial was conducted to investigate the clinical toxicity, pharmacokinetics, and chemiluminescence (CL) responses of alveolar macrophages (AMs), peripheral blood neutrophils, and monocytes after subcutaneous injection of recombinant interferon-gamma (rIFN-gamma). Six patients with lung cancer received rIFN-gamma subcutaneously as single doses of 0.2, 0.6, and 1.8 mg. Bronchoalveolar lavage was performed three times: 21 h before as well as 6-7 and 27 h after injection. Serum samples were taken five times during the 27-h follow-up. IFN concentrations were measured from alveolar epithelial lining fluid (ELF) and serum by using an antiviral bioassay. IFN-gamma was not detectable in ELF after subcutaneous injection. AMs did not effect an increase in CL responses to N-formyl-methionyl-leucyl-phenylalanine or to phosphate-buffered saline. Circulating IFN-gamma was detectable at 3-12 h after an injection of 1.8 mg of rIFN-gamma, the highest dose given. CL responses of peripheral blood monocytes increased in all patients after injection, whereas the responses of neutrophils were less clear-cut. All patients developed systemic side effects such as transient fever, nausea, headaches, and flu-like symptoms. The findings suggest that rIFN-gamma passes poorly from the blood to the pulmonary alveoli. On the basis of this and our previous findings of increased CL responses in AMs and measurable IFN concentrations in ELF after inhalation of rIFN-gamma, we recommend inhalation rather than the parenteral route of IFN-gamma for the treatment of respiratory diseases.

Adult↗
PubMed1993

Flow cytometric determination of CD11b upregulation in vivo.

We describe a flow cytometric method to evaluate upregulation of peripheral blood neutrophil and monocyte integrin CD11b in vivo. To avoid spontaneous upregulation in vitro, buffy coat cells were separated on ice and all subsequent cell handling steps were carried out at 0-4 degrees C. Such leukocytes were 95-100% viable, as determined by PI staining. Buffy coat leukocytes were double-stained with CD11b PE-conjugated and CD14 FITC-conjugated monoclonal antibodies and, in addition, with the nucleic acid dye LDS-751. After staining, firstly, LDS-751 positive (+ve) leukocytes, and, secondly, CD14 +ve monocytes were collected in live mode. Aggregated and irrelevant cells were gated out on the basis of their LDS-751 staining pattern and cellular light scattering properties, and the CD11b expression on neutrophils and monocytes was determined. Upregulation of CD11b in vitro was significantly affected by factors such as cell handling temperature, pre-fixation of blood samples, and density gradient separation of the cells. Incubation of aliquots of buffy coat cell suspension supplemented with FMLP for 5 min or without FMLP supplement for 15 min at 37 degrees C significantly increased CD11b expression without affecting cell viability. We have demonstrated that CD11b is expressed at maximal levels on arthritic synovial fluid neutrophils and CD14 +ve cells, and at increased but submaximal levels on peripheral blood neutrophils and monocytes of patients recovering from sepsis. The results suggest that the method can be used to evaluate in vivo upregulation of CD11b.

Adult↗
PubMed1993

Functions of polymorphonuclear leukocytes in early rheumatoid arthritis.

We carried out a prospective study on clinical variables and functions of polymorphonuclear leukocytes (PMNs) of 20 patients with early rheumatoid arthritis (RA) and compared the results with the presence of erosions before treatment and at a one-year follow-up. Migration of PMNs determined by agarose and filter assays and respiratory burst of PMNs determined by luminol-enhanced chemiluminescence (CL) test were studied both before starting RA-modifying treatment and 6-12 (mean 7.3) months later. PMNs of the patients without erosions at one year, as compared to the patients with erosions, showed significantly depressed migration into filter and significantly depressed CL responses to N-formyl-methionyl-leucyl-phenylalanine, both before starting the treatment and at 7.3 months. Although causality remains uncertain, the results suggest that depressed functional capacity of PMNs is associated with low risk of joint destruction in early RA.

Adult↗
PubMed1992

Oxygen radical production and trapping in subjects with previous Yersinia infection.

Previous studies indicate that oxygen radical production by 1-min activation of N-formyl-methionyl-leucyl-phenylalanine-induced chemiluminescence (CL) by whole blood is increased in subjects with previous Yersinia arthritis (YA). This finding is confirmed in the present study and extended further by demonstrating that subjects with previous YA show increased oxygen radical generation and enhanced release of myeloperoxidase from neutrophils and increased CL activity by serum, all factors that can contribute to an increase in the initial activation of CL. Initial activation was not increased in subjects who had had Yersinia enteritis without arthritis; however, intracellular oxygen radical production by purified neutrophils was significantly increased, suggesting that the cells had been primed in vivo. The water-soluble antioxidants of plasma samples tested by a peroxyl radical-trapping assay were much the same in subjects with previous YA, in subjects with previous Yersinia enteritis without arthritis, and in healthy subjects. The results suggest that aberrations in neutrophil oxygen radical production play a role in the pathogenesis of YA.

Adult↗
PubMed1992

Gut and spondyloarthropathies.

There is a link between gut and spondyloarthropathies, which extends from the acute ReA triggered by enteritis due to gram-negative bacteria to ankylosing spondylitis and peripheral arthritis in association with Crohn's disease and ulcerative colitis. In addition, in studies using ileocolonoscopy, an unexpectedly high proportion of patients with prolonged or chronic seronegative oligoarthritis or sacroiliitis have inflammatory changes in the terminal ileum or colon or both. These changes have either features of acute gut inflammation or infection, but about one quarter of the patients have chronic lesions, probably early Crohn's disease. The conventional treatment of spondyloarthropathies consists of liberal use of NSAIDs, local corticosteroid injections if indicated, and physiotherapy. In patients with acute ReA, the conventional antimicrobial therapy to eradicate the triggering infection is necessary if there is evidence of chlamydial or gonococcal etiology. This therapy does not, however, influence the course of the subsequent arthritis. Patients with chlamydia arthritis probably host living bacteria for prolonged periods, and they seem to benefit from a prolonged antimicrobial therapy with tetracyclines. In the face of frequent gut involvement in patients with prolonged or chronic spondyloarthropathies, the use of sulfasalazine is the logical alternative, as short-term studies on patients with ankylosing spondylitis indicate.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1991

Double-blind, placebo-controlled study of three-month treatment with lymecycline in reactive arthritis, with special reference to Chlamydia arthritis.

We conducted a double-blind, placebo-controlled, randomized study of 3-month treatment with lymecycline, a form of tetracycline, in reactive arthritis (ReA). Lymecycline therapy significantly decreased the duration of the illness in patients with Chlamydia trachomatis-triggered ReA, but not in other ReA patients. In 2 ReA patients, C trachomatis was found in the throat, an uncommon locale for this organism. Our results suggest that it is important to verify the triggering microbe and that it is beneficial to treat Chlamydia arthritis patients with a prolonged course of tetracycline.

Adult↗
PubMed1991

Increased whole blood chemiluminescence in patients with Shwachman syndrome: therapy trial with thiamine and alpha-tocopherol.

Neutrophils purified from peripheral blood of patients with the Shwachman syndrome show enhanced chemiluminescence (CL) and depressed chemotaxis. Here we present data showing that the increased CL response can be demonstrated by using a whole blood CL assay. This assay is well-suited for studies in infants, because the blood sample volumes needed are small. Increase in CL was most distinct in the initial (1 min) activation induced by N-formyl-methionyl-leucyl-phenylalanine. The 1-min response is considered to derive from extracellular production of oxygen radicals. Such an extracellular oxygen radical production may render the patients susceptible to undue oxidant stress. We therefore treated the patients with two antioxidants, thiamine and alpha-tocopherol, for 3 months. This supplementation, however, failed to exert any significant effect on either whole blood CL or migration of the patients' neutrophils under agarose.

Antioxidants↗