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J M Rolland

Publications and source records attributed to J M Rolland.

At least 19 recordsLinked to original sources
PubMed1999

Asthmatic airway biopsy specimens are more likely to express the IL-4 alternative splice variant IL-4delta2.

BACKGROUND: The human IL4 gene, has been shown to express the alternatively spliced messenger (m)RNA IL-4delta2. IL-4delta2 is missing the entire sequence from exon 2 and has been identified as an IL-4 receptor antagonist. OBJECTIVE: We sought to distinguish IL-4 and IL-4delta2 mRNA in respiratory tract tissue for the first time. METHODS: A novel competitive PCR assay was established with primers designed on either side of the alternative splice junction of the IL4 gene, allowing the simultaneous quantitation of both IL-4 and IL-4delta2 mRNA from one reaction. RESULTS: IL-4 and IL-4delta2 were differentially expressed in 4 nasal polyps. No difference was seen in endobronchial biopsy specimens for IL-4 mRNA expression between control subjects (median, 2.8 x 10(2) copies/microg RNA; range, 0-3.7 x 10(3) copies/microg RNA) and asthmatic subjects (median, 1.4 x 10(2) copies/microg RNA; range, 0-4.7 x 10(2) copies/microg RNA). However, significantly more asthmatic subjects (6 of 9) than control subjects (1 of 7) expressed IL-4delta2 (P =. 036). Expression of IL-4 variants was unaffected by atopic status. CONCLUSIONS: Given that IL-4delta2 is an IL-4 receptor antagonist, these results indicate that it is crucial to be able to distinguish IL-4delta2 from IL-4 when assessing IL4 gene expression. Increased expression of IL-4delta2 in stable asthmatic subjects suggests that the balance of IL-4 and IL-4delta2 may modulate asthmatic inflammation.

Adult↗
PubMed1999

T-cell receptor contact and MHC binding residues of a major rye grass pollen allergen T-cell epitope.

BACKGROUND: T cells are pivotal in the elicitation of allergic diseases. Analogues of T-cell epitope peptides with a modification at a T-cell receptor (TCR) contact site can alter selected T-cell effector functions. Thus the ability to modulate allergen-specific T-cell responses towards TH1 -like by stimulation with peptide analogues may downregulate allergic inflammation. OBJECTIVES: The purpose of this study was to characterize the minimal epitope recognized by cloned T cells of a dominant Lol p 5 epitope, p105-116, and identify the critical residues involved in TCR and MHC contact. METHODS: Using peptides with progressive truncation of N- and C-terminal residues in T-cell proliferation assays, we identified the core epitope recognized by cloned CD4(+) T cells. An additional series of peptides with single amino acid substitutions were used in T-cell proliferation and live-cell MHC binding assays. Taken together, these results allowed identification of MHC binding and TCR contact residues of p105-116. RESULTS: The core epitope of p105-116 was identified as residues 107-114. Within this core epitope, 3 residues were found to be important for MHC binding, positions 107, 110, and 112, whereas those at positions 108, 109, 110, 111, and 113 were putative TCR contact residues. CONCLUSIONS: The identification of the TCR and MHC contact residues of a dominant Lol p 5 T-cell epitope and analogues of this peptide capable of modulating T-cell responses will allow the evaluation of these peptides' potential as immunotherapeutic agents for rye grass pollen allergic disease.

Allergens↗
PubMed1999

Immunologic significance of respirable atmospheric starch granules containing major birch allergen Bet v 1.

BACKGROUND: Birch-pollen allergens are an important cause of early spring hay fever and allergic asthma. Recently, we reported a mechanism for the release of respirable allergenic particles from birch pollen containing the major allergen Bet v 1. In this study, we aimed to assess the immunologic significance of the released Bet v 1-containing starch granules in the environment. METHODS: A two-site monoclonal antibody-based assay (ELISA) was employed to quantitate Bet v 1 in high-volume air sampler filter extracts, and immunogold-labelling was used on sections of these extracts to localize Bet v 1. Immunoblot analyses were performed with pooled sera from patients sensitive to birch pollen. RESULTS: Atmospheric starch granules contained Bet v 1, and the concentration increased upon light rainfall. Sera from patients allergic to birch allergens recognized extracts from isolated starch granules. CONCLUSIONS: The clinical implications of these findings are that starch granules released from birch pollen are potentially able to trigger allergic asthmatic reactions to Bet v 1, since the allergen occurs in respirable particles. Thus, clinicians can advise asthma patients to remain indoors on days of light rainfall during the birch-pollen season to avoid high levels of allergen exposure.

Air Pollution↗
PubMed1999

Modulatory effects of alveolar macrophages on CD4+ T-cell IL-5 responses correlate with IL-1beta, IL-6, and IL-12 production.

Increasing evidence suggests that the pattern of T-cell cytokine production can be modulated by antigen presenting cell (APC)-derived factors during the cell interactions. Recently, it has been shown that alveolar macrophages (AMs) from atopic asthmatics (AA) but not atopic nonasthmatics (AN) enhance interleukin (IL)-5 production by CD4+ T-cells. The present study compared AM production of IL-1beta, IL-6, and IL-12, as well as their associated functional capacity to influence IL-5 production by allergen-specific CD4+ T-cells in 10 AA, 10 AN, and nine nonatopic control subjects (C). AMs from AA showed a relatively high production of IL-1beta and IL-6 (p<0.05) and a relatively low secretion of IL-12 compared to C, whereas AMs from AN and C behaved similarly. This study confirmed previous findings that co-culture with AMs augments IL-5 production from allergen-stimulated CD4+ T-cells only in AA and not in nonasthmatics even if they are atopic. On the other hand, stimulation with allergen alone did not enhance IL-5 production by CD4+ T-cells in either AA nor AN. AM-induced changes in CD4+ T-cell IL-5 production upon allergen stimulation significantly correlated with their ability to produce IL-1beta (r=0.59, p<0.01), IL-6 (r=0.56, p<0.01), and inversely with IL-12 (r=-64, p=0.002) in all atopic subjects, and even more closely with the ratio of IL-12/IL-1beta (r=-0.75, p<0.001) and IL-12/IL-6 production (r=-0.81, p<0.001) in these subjects. These findings suggest that the role of alveolar macrophages from atopic asthmatics in enhancing interleukin-5 production by allergen-specific CD4+ T-cells is due, at least partly, to their aberrant production of interleukin-1beta, interleukin-6, and particularly of interleukin-12.

Adult↗
PubMed1999

A comparison of commercial and in-house ELISAs for antineutrophil cytoplasmic antibodies directed against proteinase 3 and myeloperoxidase.

This study compares the concordance of results in different ELISAs for antineutrophil cytoplasmic antibodies (ANCA) directed against proteinase 3 (PR3) or myeloperoxidase (MPO). Sera were considered "true positives" if they were positive according to the manufacturer's criteria in a least three of the five PR3-ANCA ELISAs, or in at least four of the six MPO-ANCA ELISAs. Of the 26 sera that demonstrated cytoplasmic fluorescence (C-ANCA), 23 (89%) contained PR3-ANCA and three (11%) had MPO-ANCA. Two sera that were negative by indirect immunofluorescence (IIF) contained PR3-ANCA. Of the 26 sera with perinuclear fluorescence (P-ANCA), 19 (73%) contained MPO-ANCA, and one (4%) had PR3-ANCA. Six sera with P-ANCA did not have PR3- or MPO-ANCA. No serum that was negative by IIF contained MPO-ANCA. For the different PR3-ANCA ELISAs, sensitivities ranged from 88 to 100%, and specificities from 91 to 100%. For the MPO-ANCA ELISAs, sensitivities varied from 59 to 100% and specificities from 83 to 100%. The highest sensitivity and specificity for both the PR3- and MPO-ANCA ELISAs were obtained with the IBL and Eurodiagnostica assays. The in-house PR3-ANCA ELISA performed slightly less well than the commercial assays, but the performance of the in-house MPO-ANCA assay was comparable or better.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1999

Murine allergic respiratory responses to the major house dust mite allergen Der p 1.

BACKGROUND: Although many studies have examined chronic asthma, limited data exist on acute immunopathogenic events induced by allergens. The aim of the study was to investigate the acute cellular, serologic and histopathologic events in airway inflammation produced by intranasal challenge of mice sensitised to the major house dust mite allergen Der p 1. METHODS: C57BL/6 mice were immunised subcutaneously with Der p 1 in alum. Mice were bled and challenged intranasally with Der p 1 on day 14 and killed on day 17. Lungs were fixed in situ, processed and stained with haematoxylin and eosin. The degree of inflammation and eosinophil infiltration was quantified by image analysis. Specific IgE was determined by passive cutaneous anaphylaxis. Cells from spleen and draining lymph nodes were cultured for 24 h with Der p 1, and IL-3/GM-CSF released into supernatants was measured by bioassay. RESULTS: Intranasal challenge of sensitised mice induced eosinophilic influx into the large and small airways and the alveolar regions of the lung, mucus plugging and in severe cases numerous Charcot-Leyden crystals. The quantitation of the inflammation induced by different sensitisation and challenge doses showed that optimal inflammation could be produced using only 1 microg of allergen for both sensitisation and challenge. The degree of inflammation was not related to the titre of IgE antibody and was indeed produced in its absence. T cell reactivity of spleen cells to the allergen was decreased suggesting cell migration or inactivation. CONCLUSIONS: Mice sensitised and challenged intranasally with as little as 1 microg of Der p 1 produced an extensive pulmonary eosinophilic inflammation which shared many of the features of the inflammation found in asthma. The small amount of allergens required and the use of intranasal challenge should provide a useful model.

Allergens↗
PubMed1998

Differential regulation of allergen-specific T(H2)- but not T(H1)-type responses by alveolar macrophages in atopic asthma.

BACKGROUND AND OBJECTIVE: Previous studies have suggested that quantitative differences in TH2-type cytokine responses in the airways are of particular importance in the pathogenesis of asthma. In this study we investigated whether alveolar macrophages (AMs) and peripheral blood monocytes (PMNs) are able to significantly influence the profiles of allergen-induced TH1 (IFN-gamma) and TH2 (IL-4 and IL-5) cytokine production by CD4+ T cells in atopic asthmatic subjects versus atopic nonasthmatic subjects and nonatopic normal subjects. METHODS: Peripheral blood CD4+ T cells were cultured alone or cocultured with either PMNs or AMs with allergen stimulation in the 3 groups. RESULTS: Although allergen stimulation did not change TH1 or TH2 cytokine responses in cultures of CD4+ T cells alone, the addition of PMNs to the cultures induced a significant increase in production of IL-4, IL-5, and IFN-gamma (P < .01 or P < .001) in atopic asthmatic subjects and atopic nonasthmatic subjects. However, PMNs induced a significant increase for IFN-gamma (P < .05) only in normal subjects. AMs from atopic asthmatic subjects significantly enhanced production of all 3 cytokines (P < .01 or P < .001), whereas the AMs from atopic nonasthmatic subjects significantly increased only production of IL-4 (P < .01) and IFN-gamma (P < .05) but not IL-5. Furthermore, IL-4 (P = .066) and IL-5 (P < .01) production in allergen-stimulated AM-CD4+ cell cocultures was higher in atopic asthmatic subjects but significantly lower in atopic nonasthmatic subjects (P < .05) as compared with the PMN-cocultures. For IFN-gamma, no difference was found between the AM and PMN cocultures in either atopic group. Allergen-stimulated IL-5 production in coculture with both AMs and PMNs inversely correlated with both baseline FEV1 percent predicted and PD20 methacholine in atopic asthmatic subjects (P < .05, P < .01, or P < .001). CONCLUSION: These data suggest that AMs from atopic asthmatic subjects but not atopic nonasthmatic subjects, play a significant role in airway pathogenic immunity through enhancing TH2-type cytokine production.

Adolescent↗
PubMed1998

Molecular basis of IgE-recognition of Lol p 5, a major allergen of rye-grass pollen.

Grass pollen, especially of rye-grass (Lolium perenne). represents an important cause of type I allergy. Identification of IgE-binding (allergenic) epitopes of major grass pollen allergens is essential for understanding the molecular basis of interaction between allergens and human IgE antibodies and therefore facilitates the devising of safer and more effective diagnostic and immunotherapy reagents. The aim of this study was to identify the allergenic epitopes of Lol p 5, a major allergen of rye-grass pollen, immunodissect these epitopes further so that the amino acid residues critical for antibody binding can be determined and investigate the conservation and nature of these epitopes within the context of the natural grass pollen allergens. Peptides, 12-13 amino acid residues long and overlapping each other by 4 amino acid residues, based on the entire deduced amino acid sequence of the coding region of Lol p 5, were synthesised and assayed for IgE-binding. Two strong IgE-binding epitopes (Lol p 5 (49-60) and (265-276), referred to as peptides 7 and 34, respectively) were identified. These epitopes were further resolved by truncated peptides and amino acid replacement studies and the amino acid residues critical for IgE-binding determined (Lol p 5 (49-60) residue Lys57 and (265-276) residue Lys275). Sequences of these epitopes were conserved in related allergens and may form the conserved allergenic domains responsible for the cross-reactivity observed between pollen allergens of taxonomically related grasses. Furthermore, due to its strong IgE-reactivity, synthetic peptide Lol p 5 (265-276) was used to affinity-purify specific IgE antibodies which recognised proteins of other clinically important grass pollens. further indicating presence of allergenic cross-reactivity at the level of allergenic epitope. Moreover, Lol p 5 (265 276) demonstrated a strong capacity to inhibit IgE-binding to natural rye-grass pollen proteins highlighting the antibody accessibility to these sequences within the context of the natural allergens. Strong IgE-binding epitopes of Lol p 5 have been identified down to single critical amino acid residues and are shown to occur as linear or continuous domains in the natural conformation of natural Lol p 5 and other group 5 grass pollen allergens. The fact that such an allergenic synthetic epitope has the capacity to strongly inhibit IgE-binding to natural allergens highlight its potential for use as a candidate in future therapeutics to treat pollen-associated allergies.

Allergens↗
PubMed1998

Alveolar macrophages from atopic asthmatics, but not atopic nonasthmatics, enhance interleukin-5 production by CD4+ T cells.

Recent studies have demonstrated that different antigen-presenting cell (APC)-related factors in the microenvironment of a T cell may determine its profile and quantity of cytokine expression and production. We have therefore examined the effects of alveolar macrophages and peripheral blood monocytes on interleukin (IL)-5 production by peripheral blood CD4+ T cells from atopic people with asthma (AA), atopic people without asthma (AN), and nonatopic normal subjects (N). In response to allergen stimulation, IL-5 production was significantly enhanced by the addition of monocytes to CD4+ cell cultures in AA and AN patients (p < 0.05 and 0.01, respectively), but not in N subjects. In mitogen-stimulated CD4+ cell plus monocyte cocultures, there was a small increase in IL-5 production in all three groups (p < 0.05 for AN). In contrast, the addition of alveolar macrophages to parallel cultures significantly amplified IL-5 production only in AA patients (p < 0.05 or 0.01). Furthermore, IL-5 production by CD4+ cells in alveolar macrophage cocultures, stimulated by allergen or mitogen, was higher than that in monocyte cocultures in AA patients (p < 0.05). Conversely, in AN and N subjects, the IL-5 values for alveolar macrophage cocultures were lower than those for peripheral blood monocytes. In blocking studies, antibodies against IL-1alpha, IL-1beta, IL-6, or tumor necrosis factor-alpha differentially suppressed macrophage-enhanced IL-5 production (p < 0.05 for IL-1beta and IL-6) and expression of the activation marker CD25 (p < 0.05 for IL-1alpha and IL-6) by allergen-stimulated CD4+ cells in AA patients. These observations suggest that alveolar macrophages influence the quantity of IL-5 production by T cells in the airways and, as a consequence, the development of asthma in atopic individuals.

Adult↗
PubMed1997

Allergen-induced airway reactions in atopic asthmatics correlate with allergen-specific IL-5 response by BAL cells.

Allergen-specific cytokine responses in the airways are thought to play a critical role in the pathogenesis of atopic asthma. This study examined whether there is a quantitative difference in bronchoalveolar lavage (BAL) cell allergen-induced IL-5 production between atopic subjects with and without asthma which may relate to a difference in airway response induced by allergen exposure. Twelve atopic asthmatics (AA), nine atopic non-asthmatics (AN) and 10 normal controls (N) underwent inhalation challenge with house dust mite allergen (HDM) extract. AA differed from AN in having late airway reactions (LAR) after HDM inhalation (P < 0.01), which correlated with an increased percentage of BAL eosinophils and increased BAL cell IL-5 production after in vivo or in vitro HDM challenge for the AA group (P < 0.01). IL-5 production by PBMC from both atopic groups was elevated with HDM stimulation in vitro, but AA again had a higher level under baseline conditions than AN (P < 0.02). Furthermore, there was a greater effect of BAL fluid from AA on ECP release by eosinophils compared to that for AN (P < 0.01). These findings suggest that increased IL-5 production in atopic asthmatic airways contributes to the increased physiological response to allergen inhalation, by modulating local eosinophil recruitment and activation.

Adult↗
PubMed1997

IL-5 production by bronchoalveolar lavage and peripheral blood mononuclear cells in asthma and atopy.

There is increasing evidence to suggest a key role for interleukin-5 (IL-5) in the regulation of airway eosinophilia in asthma. We compared the capacity for IL-5 production in atopic asthmatic, nonatopic asthmatic, atopic nonasthmatic and normal subjects, and evaluated the usefulness of peripheral blood cells for reflecting airway cell reactivity. Bronchoalveolar lavage (BAL) cells and peripheral blood mononuclear cells (PBMC) from 12 atopic and 10 nonatopic asthmatics (without inhaled steroid therapy), 9 atopic nonasthmatics, and 10 normal controls were cultured with or without house dust mite (HDM, 10 microg x mL-1) stimulation. CD4+ T-cell activation, IL-5 and interferon-gamma (IFN-gamma) production in the cultures were assessed. Both for BAL and PBMC samples, atopic and nonatopic asthmatic subjects showed comparable spontaneous production of IL-5, which was significantly higher than that either for atopic nonasthmatics or normal controls (p<0.05 or p<0.01). There was a significant correlation between the percentage of eosinophils in BAL and spontaneous production of IL-5 by BAL cells in both asthmatic groups (p<0.05 or p<0.01). Both these parameters were also associated with asthmatic airway narrowing as denoted by a negative relationship with baseline forced expiratory volume in one second (FEV1) as percentage predicted (p<0.05 and p<0.01, respectively). In contrast, IFN-gamma production by unstimulated BAL cells from normal controls was higher than that for BAL cell cultures of nonatopic asthmatic subjects (p<0.05). Following HDM stimulation, both atopic groups had comparable positive responses in terms of CD4+ T-cell activation, but there was relatively greater IL-5 production in asthmatic PBMC (p<0.05) and, in particular, BAL cell cultures (p<0.01). These findings suggest that elevated IL-5 production is a common feature of BAL cells and PBMC in atopic and nonatopic asthma. In addition, atopic asthmatics show greater IL-5 production in response to specific allergen compared with atopic nonasthmatics, an effect most marked in BAL cells compared to PBMC. Hence, peripheral blood mononuclear cells can reflect cytokine immunoreactivity of airway cells, but lack local cellular interactions, which limits their usage in asthma research.

Adult↗
PubMed1997

[In coronary surgery can both internal mammary arteries be used systematically? Apropos of 560 patients].

The grafts commonly used in coronary bypass surgery are the left internal mammary artery and the saphenous veins of the legs: the use of both internal mammary arteries, with potential long-term benefits, is only justified if the operative risk is not increased. Since 1987, the authors use both internal mammary arteries systematically in patients under 70 years of age and in good general condition. The retrospective analysis of 560 patients having undergone this surgery from 1987 to 1994 was undertaken to determine if this surgical option is justified without increased operative risk. The dissection of the mammary arteries is performed in a special manner by skeletonization technique. The total hospital complication rate was 12% with 9 deaths in the first 30 postoperative days (1.6%). Mediastinitis was observed in 6 patients (1.1%) Early angiographic controls showed a patent mammary graft rate of 98%. The use of both internal mammary arteries does not therefore increase postoperative morbidity or mortality. It may be proposed systematically in patients in good general condition and may provide long-term benefits in graft patency rates.

Adult↗
PubMed1996

Identification of T-cell epitopes of Lol p 9, a major allergen of ryegrass (Lolium perenne) pollen.

T-cell recognition of Lol p 9, a major allergen of ryegrass pollen, was investigated by using a T-cell line and T-cell clones generated from the peripheral blood of an atopic donor. The T-cell line reacted with purified Lol p 9, as well as with crude ryegrass pollen extract, but failed to cross-react with Bermuda grass pollen extract. All of six T-cell clones generated from this line proliferated in response to Lol p 9. Epitope mapping was carried out with a panel of 34 overlapping synthetic peptides, which spanned the entire sequence of the Lol p 9 12R isoform. The T-cell line responded to two of the peptides, Lol p 9 (105-116) and Lol p 9 (193-204), whereas reactivity with one or other of these peptides was shown by five T-cell clones. These two peptides contained sequences consistent with motifs previously reported for major histocompatibility complex class II-restricted peptides. HLA antibody blocking studies showed that presentation of peptide Lol p 9 (105-116) to one T-cell clone was HLA-DR-restricted; this clone expressed a T helper cell phenotype (CD3+, CD4+) and the T-cell receptor alpha beta. The identification of immunodominant T-cell epitope(s) on allergens is essential for devising safer and more effective immunotherapy strategies, which can interrupt the chain of events leading to allergic disease.

Allergens↗
PubMed1995

T cell response to grass pollen allergens: correlation with skin test reactivity and serum IgE levels.

T cell proliferative responses to rye and Bermuda grass pollen allergens have been studied in a series of 51 atopic and 18 non-atopic subjects. Mean T cell responses were higher in the atopic group than in the non-atopic group (P < 0.001), and there was a strong correlation between the magnitude of reaction in the T cell assay and in the skin test (rye P < 0.01, Bermuda P < 0.05). A similar association was shown between T cell reactivity and serum levels of allergen-specific IgE (rye P < 0.05, Bermuda P < 0.05), but no relationship was found between serum allergen-specific IgG levels and any other parameter studied. T cell reactivity was not found in three cord blood samples tested. Discordance between positivity for T cell responses and skin test reactions in some cases might reflect reactivity by T cell subsets that promote IgG antibody or cell-mediated responses without IgE antibody production. A precise knowledge of T cell recognition of grass pollen allergens will provide exciting new prospects for more effective and safer immunotherapy strategies for allergic diseases including asthma.

Adult↗
PubMed1993

[False aneurysm of the left ventricle and coronary aneurysms in Behçet disease].

A false left ventricular aneurysm and coronary artery aneurysm were discovered in a 29 year old patient with Behçet's syndrome. The operation under cardiopulmonary bypass consisted of closing the neck of the false aneurysm by an endo-aneurysmal approach with a Gore-Tex patch. The coronary artery aneurysms were respected. There were no postoperative complications. Cardiac involvement is rare in Behçet's syndrome (6%). The originality of this case is the association of two aneurysmal pathologies: the coronary and ventricular aneurysms due to the angiitis and the myocardial fragility induced by ischaemia.

Adult↗
PubMed1989

Autoantibodies to neurons and to the cytoskeleton in small cell carcinoma with paraneoplastic sensory neuropathy.

Autoantibodies to neurons and to the cytoskeleton were demonstrated in the serum of a patient with small cell carcinoma of the lung (SCCL) and paraneoplastic sensory neuropathy. The serum reacted by immunofluorescence with the nuclei of neurons, and with cytochalasin B-sensitive "stress fibres" of cultured cells. The serum also reacted by immunofluorescence with the nuclei of some cultured cell lines. Immunoblotting experiments with brain tissue, with SCCL, HeLa and other cultured cells showed that the serum reacted with 1-4 bands of 35-39 kDa apparent m.w. Two dimensional immunoblotting showed that these molecules had a neutral pI. Antibodies, affinity-purified by elution from the 35-39 kDa bands, gave staining of the nuclei of neurons and of cultured cells and immunoblotted the same 35-39 kDa antigens. These observations show that the anti-neuronal autoantibody reacts not only with neurons and with SCCL but also with some cultured cell lines. Molecular mimicry has been invoked as the basis for the reactivity of this autoantibody with exposed epitopes on SCCL and on neurons.

Animals↗