[Chronic hypersensitivity pneumonitis].
Explore the source record for details and available documents.
Alveolitis, Extrinsic Allergic↗
Biomedical subjects
Susumu Isogai
Publications and source records attributed to Susumu Isogai.
[Chronic hypersensitivity pneumonia].
Explore the source record for details and available documents.
Alveolitis, Extrinsic Allergic↗
Resident CD8+ T cells suppress CD4+ T cell-dependent late allergic airway responses.
BACKGROUND: The role of CD8+ T cells in the immune response to airway challenge with an allergen is poorly understood. OBJECTIVE: The aim of this study was to test the hypothesis that resident naive CD8+ T cells modulate the magnitude of CD4+ T cell-dependent allergic airway responses. METHODS: Cervical lymph node CD4+ T cells (2 x 10(6)) were harvested from ovalbumin (OVA)- or sham-sensitized rats and injected intraperitoneally into naive Brown Norway recipients. The recipients were treated with a CD8alpha mAb (OX-8) to deplete the resident CD8+ T cells (n = 12) or mouse ascites (n = 12). Two days after adoptive transfer, the recipient animals were OVA challenged, lung resistance was measured for 8 hours, and bronchoalveolar lavage (BAL) was performed. RESULTS: After OVA challenge, primed CD4-transferred CD8-depleted rats had larger early airway responses and late airway responses compared with primed CD4-transferred CD8-nondepleted rats (early airway responses: 158.6% +/- 19.2% vs 115.7% +/- 5.9%, P < .05; late airway responses: 8.5% +/- 1.7% vs 4.4% +/- 0.9%, P < .05). BAL eosinophilia was also greater (4.67% +/- 0.45% vs 2.34 +/- 0.26%, P < .01). The cells in BAL fluid expressing IL-4 mRNA were not significantly changed by CD8 depletion, but IL-5 mRNA+ cells were higher in number, and IFN-gamma mRNA+ cells were fewer in the CD8-depleted group. CONCLUSIONS: Resident CD8+ T cells downregulate the late allergic response and airway inflammation evoked by CD4+ T-cell transfers in Brown Norway rats. This downregulation does not require antigen priming.
Adoptive Transfer↗
CD4+ T cells migrate from airway to bone marrow after antigen inhalation in rats.
BACKGROUND: IL-5-producing T lymphocytes increase in rat bone marrow after inhalational challenge with allergen. OBJECTIVE: To test the hypothesis that T cells migrate from the airways to the marrow, we examined the trafficking of T cells in Brown Norway rats after sensitization and challenge with ovalbumin. METHODS: Purified CD4+ T cells, harvested from cervical lymph nodes of naive and ovalbumin-sensitized donors, were labeled with carboxy fluorescein diacetate succinimidyl ester; 20 x 10(6) cells were placed in the trachea of naive or sensitized recipients under anesthesia, and 18 hours later, animals were challenged with inhaled ovalbumin. Cells were harvested 24 hours later from the bone marrow, bronchoalveolar lavage fluid, lungs, the lung blood pool of cells, lung draining lymph nodes, peripheral blood, and spleen. RESULTS: The number of carboxy fluorescein diacetate succinimidyl ester-positive cells, measured by fluorescence-activated cell sorter, in the bone marrow of ovalbumin sensitized, primed T-cell recipients was higher than either the sham-sensitized, primed T-cell recipients or sham-sensitized, naive T-cell recipients (P < .05). The number of eosinophils in both bone marrow and bronchoalveolar lavage fluid was increased in ovalbumin-sensitized, primed T-cell recipients. The expression of the T-cell chemoattractants eotaxin and IL-16, evaluated by immunohistochemistry, was higher in the bone marrow of ovalbumin-sensitized, primed T-cell recipients. CONCLUSIONS: CD4+ T cells travel from airway to bone marrow after antigen inhalation. The homing of the CD4+ T cells might be facilitated by eotaxin and IL-16 expression in the bone marrow and might contribute to the stimulation of eosinophilopoiesis after airway allergen exposure.
Administration, Inhalation↗
CD8+ alphabeta T cells can mediate late airway responses and airway eosinophilia in rats.
BACKGROUND: The function of CD8+ T-cell subsets in mediating late allergic responses is incompletely understood. OBJECTIVE: We sought to test the hypothesis that CD8+ alphabeta T cells are proinflammatory in the airways in vivo by using a well-characterized animal model and the technique of adoptive transfer. METHODS: Brown Norway rats were administered CD8 + alphabeta T cells (10 6 ) intraperitoneally purified from lymph node cells of either naive or ovalbumin (OVA)-sensitized rats and were challenged with aerosolized OVA 2 days later. Control rats were sensitized to 100 mug of OVA in Al(OH) 3 subcutaneously or sham sensitized to saline and were OVA challenged 2 weeks later. RESULTS: The OVA-sensitized and OVA-challenged group and the recipients of OVA-primed CD8+ alphabeta T cells had significant late airway responses calculated from lung resistance measured for an 8-hour period after challenge compared with the naive CD8 + alphabeta T cell-transferred group and the sham-sensitized control group. The number of eosinophils in bronchoalveolar lavage fluid increased in the OVA-sensitized group and the OVA-primed CD8+ alphabeta T-cell recipients compared with numbers in the naive CD8+ alphabeta T-cell recipients and the sham-sensitized control group. IL-4 and IL-5 cytokine mRNA expression in bronchoalveolar lavage fluid increased in the OVA-sensitized group and the OVA-primed CD8+ alphabeta T-cell recipients compared with that in the sham-sensitized group. CONCLUSION: We conclude that antigen-primed CD8 + alphabeta T cells might have a proinflammatory role in allergen-driven airway responses in the rat.
Adoptive Transfer↗
T cell cytokines: animal models.
Allergic asthma involves a complex series of reactions within the airways that lead to inflammation and bronchoconstriction. These phenomena are closely linked to the immune response to the allergenic protein mediated by T cells with specificity for the allergen. Antigen presentation by dendritic cells initiates the allergic response, triggering the activation of CD4+ T cells predominantly. These cells secrete Th2 type cytokines, of which IL-4 and IL-5 are best understood, that act on various cells including B cells, eosinophils, macrophages and epithelial cells. These cells mediate, in turn, immunoglobulin E synthesis, and promote an eosinophil rich inflammation through the concerted action of various chemoattractant substances, both lipid-derived and proteins. CD8+ T cells are also activated and may have either anti-inflammatory or pro-inflammatory effects, depending upon the particular experimental model studied. The T cell receptor (TCR) that these cells possess has an important influence on the role they play. TCRalphabeta cells appear more likely to be pro-inflammatory and have antigen specificity whereas TCRgammadelta cells can be either pro- or anti-inflammatory, depending on species and experimental conditions and are not antigen specific. In conclusion, the magnitudes of inflammatory responses and bronchoconstriction following allergen challenge of sensitised animals are T cell driven and are determined, at least in part, by the balance of the T cell subsets that are activated.
Animals↗
[Pneumoconiosis diagnosed in a dentist].
A 74-year-old man was admitted to our hospital because of exertional dyspnea in January 2003. He had first noticed slight exertional dypnea in 1997, which had since gradually progressed. He has been a dentist since the age of 23. Chest radiography demonstrated bilateral reticular shadows, infiltrates, and thickened pleural adhesion, which had progressed for one year and five months. Chest CT scans disclosed irregular peribronchial opacities, centrilobular nodules, and interlobular septal lines. Bronchoalveolar lavage fluid showed an increase in total cells and lymphocytosis with an increased CD 4/CD 8 ratio. Transbronchial lung biopsy demonstrated fibrosis around bronchioles, involving adjacent alveolar structures and scattered birefringent particles under polarized light. Energy-dispersive X-ray analysis (EDXA) of the small particles around the bronchioles using electron microscopy showed high peaks for silicon (Si) and aluminium (Al). Pneumoconiosis, possibly induced by some of the mechanical and technical procedures of dentistry, was diagnosed.
Aged↗
The effects of CD8+gammadelta T cells on late allergic airway responses and airway inflammation in rats.
BACKGROUND: Gamma-delta (gammadelta) T cells regulate immune responses to foreign protein at mucosal surfaces. Whether they can modify allergen-induced early (EAR) and late airway responses (LAR) is unknown. OBJECTIVE: We have tested the hypothesis that the CD8+ subtype of gammadelta T cells decreases allergen-induced LAR and airway eosinophilia in the rat. METHODS: Brown Norway rats were administered, intraperitoneally, 3.5 x 10(4) lymph node CD8+gammadelta T cells from naive or sensitized rats. The recipients were sensitized to ovalbumin (OVA) in Al(OH)(3) 3 days after cell transfer and challenged with aerosolized OVA 14 days later. Serum IgE was measured before allergen challenge. After challenge, lung resistance was monitored for 8 hours and then bronchoalveolar lavage (BAL) was analyzed for eosinophil major basic protein (MBP), IL-4, IL-5, IL-13, and IFN-gamma messenger RNA-expressing cells. RESULTS: gammadelta T cells from naive donors significantly decreased LAR in OVA-challenged sensitized rats, whereas MBP(+) eosinophils were decreased by both gammadelta T cells from naive and sensitized donors. EAR and serum IgE levels were unchanged. The expression of IL-4, IL-5, and IL-13 by BAL cells of gammadelta T cell recipients was attenuated compared with OVA-challenged controls. This was accompanied by an increase in the expression of IFN-gamma. CONCLUSIONS: Our results are consistent with a suppressive role of CD8+gammadelta T cells on allergic airway responses. However, only gammadelta T cells from naive donors inhibit LAR.
Adoptive Transfer↗
Inhibition of allergic airways inflammation and airway hyperresponsiveness in mice by dexamethasone: role of eosinophils, IL-5, eotaxin, and IL-13.
BACKGROUND: Glucocorticoids inhibit allergen-induced airway eosinophilia and airway hyperresponsiveness (AHR). Whether glucocorticoids mediate their effects on AHR by inhibiting eotaxin and IL-5, 2 of the principal mediators of eosinophilia, or through IL-13, an important mediator of AHR, has not been established. OBJECTIVE: We sought to investigate the effects of glucocorticoids on airway eosinophilia and the expression of IL-5, eotaxin, and IL-13 in relation to the induction of AHR in a murine model of allergic asthma. METHODS: Dexamethasone (4 mg/kg) and mAbs against eotaxin (80 micro g/kg) and IL-5 (100 micro g/kg) singly and in combination were administered to immunized mice before antigen challenge. Airway responsiveness to methacholine was measured in anesthetized and mechanically ventilated animals. Eotaxin, IL-5, and IL-13 in bronchoalveolar lavage fluid (BALF), lung homogenates, or both were measured by means of ELISA. RESULTS: A single antigen challenge induced AHR that lasted at least 10 days. Eotaxin protein and mRNA levels increased in lung tissue but not in BALF after challenge. IL-5 protein and mRNA levels increased both in BALF and in lung tissue. Dexamethasone reduced airway eosinophilia, AHR, and protein and mRNA for eotaxin and IL-5. Anti-murine eotaxin and anti-IL-5 antibodies alone and in combination reduced the ovalbumin-induced airway eosinophilia significantly but failed to inhibit AHR. Both dexa-methasone and anti-IL-5/anti-eotaxin inhibited the increases in lung IL-13 levels after ovalbumin challenge to a similar extent. CONCLUSION: These findings suggest that the inhibition of AHR by the glucocorticoid dexamethasone does not appear to be explained by effects on eosinophilia, eotaxin, IL-5, or IL-13.
Animals↗
Cyclosporin A followed by the treatment of acute exacerbation of idiopathic pulmonary fibrosis with corticosteroid.
OBJECTIVE: Idiopathic pulmonary fibrosis (IPF) is a slowly progressive disease with a poor prognosis. Acute exacerbation is the worst stage in the clinical course of IPF, as the condition is unresponsive to most conventional therapies. Corticosteroids and other immunosuppressive drugs have been attempted for the treatment of acute exacerbation, but only with very limited effectiveness. This study was performed to examine the effect of cyclosporin A (CsA) on acute exacerbation of IPF. PATIENTS AND METHODS: Thirteen patients with acute exacerbation of IPF were retrospectively studied. All 13 patients received pulse-therapy with methylprednisolone (1,000 mg per day for 3 days), followed by oral prednisolone (40-60 mg per day). Seven patients were received CsA (1.0-2.0 mg/kg per day) after the treatment with corticosteroids. We attempted to keep the blood trough level of CsA between 100 and 150 ng/ml. RESULTS: Among the 7 patients treated with CsA, 4 patients have survived for 60, 120, 276 and 208 weeks, respectively; 2 did not respond to pulse-therapy with methylprednisolone and died within 8 weeks after the start of CsA treatment. The other patient experienced re-exacerbation and died 87 weeks after the discontinuation of CsA due to the development of viral encephalitis. In contrast, all 6 patients treated without CsA died within 66 weeks after the onset of acute exacerbation. Four of these patients responded to pulse-therapy with methylprednisolone, but their condition deteriorated again while the subsequent prednisolone was being tapered. CONCLUSION: CsA seems to prevent re-exacerbation of IPF and improve the patients' chances for long-term survival.
Acute Disease↗