Longstanding hypersensitivity pneumonitis and its response to roflumilast: A review of its likely immunological effects.

We describe the case of a 42yr old man with evidence of hypersensitivity pneumonitis referred with cough and breathlessness for several years which had further deteriorated in the prior 12 months. He had known atopic asthma without evidence of activation. A chest CT scan showed widespread ground glass change in his lung fields. He had feather bedding at home and in his youth cleaned aviaries. His forced vital capacity and lung volumes were reduced along with oxygen saturations at rest (92% on air), overnight (83% on air) and upon walking (78%). Steroids were commenced for a total of 6 months with little consistent improvement in symptoms or objective measures and with no change in his CT scan appearance. As a result, a trial of roflumilast (a phosphodiesterase-4 inhibitor) was commenced due to its range of immunological effects and in order to avoid long-term immune suppression with mycophenolate motefil in a young patient. On roflumilast treatment his cough and breathlessness improved at 4 weeks and the chest crackles cleared. An interval Chest CT scan showed resolution of the ground glass change with improved CT scores that are maintained 2 yrs. All oxygen measures improved and nocturnal oxygen was discontinued. His Lung function has remained largely stable on roflumilast and symptoms of cough and breathlessness have resolved. This case report reviews the immunology of hypersensitivity pneumonitis and the likely actions of Roflumilast relevant to this condition. It is the first published case report documenting its use in hypersensitivity pneumonitis.

IgE-Mediated Systemic Anaphylaxis And Its Association With Gene Polymorphisms Of ACE, Angiotensinogen And Chymase.

BACKGROUND: The renin-angiotensin system (RAS) protects the circulation against sudden falls in systemic blood pressure via generation of angiotensin II (AII). Previously, we demonstrated that patients with anaphylaxis involving airway angioedema and cardiovascular collapse (AACVS) had significantly increased "I" gene polymorphisms of the angiotensin-converting-enzymes (ACE). This is associated with lower serum ACE and AII levels and was not seen in anaphylaxis without collapse nor atopics and healthy controls. OBJECTIVES: To examine the angiotensinogen (AGT-M235T) and chymase gene (CMA-1 A1903G) polymorphisms in these original subjects. METHOD: 122 patients with IgE-mediated anaphylaxis, 119 healthy controls and 52 atopics had polymorphisms of the AGT gene and chymase gene examined by polymerase chain reactions and gel electrophoresis. Their previous ACE genotypes were included for the analysis. RESULTS: AGT-MM genes (associated with low AGT levels) were significantly increased in anaphylaxis (Terr's classification). When combined with ACE, anaphylaxis showed increased MM/II gene pairing (p<0.0013) consistent with lower RAS activity. For chymase, there was increased pairing of MM/AG (p<0.005) and AG/II and AG/ID (p<0.0073) for anaphylaxis consistent with lower RAS activity. A tri-allelic ensemble of the 6 commonest gene combinations for the healthy controls and anaphylaxis confirmed this difference (p=0.0001); for anaphylaxis, genes were predominately MM/AG/II or ID, while healthy controls were DD/MT/AG or GG patterns. CONCLUSION: Our gene polymorphisms show lower RAS activity for anaphylaxis especially AACVS. Animal models of anaphylaxis are focused on endothelial nitric oxide (eNO) which is shown to be the mediator of fatal shock and prevented by eNO-blockade. The interaction of AII and eNO controls the microcirculation in man. High serum AII levels reduce eNO activity, so higher RAS-activity could protect against shock. Our data shows low RAS activity in anaphylaxis especially AACVS, suggesting the influence of these genes on shock are via AII levels and its effects on eNO.

IgE-Mediated Anaphylaxis to Foods, Venom, and Drugs: Influence of Serum Angiotensin Converting Enzyme Levels and Genotype.

Circulating angiotensin-II protects the circulation against sudden falls in blood pressure and is generated by the enzymatic action of angiotensin converting enzyme (ACE) on angiotensin-I. The ACE genes have 2 allelic forms, "I" and "D." The "D" genotype has both highest angiotensin-II generation and serum ACE levels compared to "I". 120 patients with IgE-anaphylaxis, 119 healthy controls, and 49 atopics had serum ACE levels, ACE genotype, and renin levels determined. Plasma renin levels were identical for all groups. Serum ACE levels and genotypes were similar for healthy controls (HC) and atopics, but lower in anaphylaxis (P = 0.012), with ACE genotypes also showing increased "I" genes (P = 0.009). This effect was more pronounced in subjects manifesting airway angioedema and cardiovascular collapse (AACVS) than mild cutaneous and respiratory (CRA) symptoms. AACVS was significantly associated with the presence of "I" genes. For "ID" genotype OR is 5.6, 95% CI 1.8 to 17.4, and for "II" genotype OR is 44, 95% CI 5 to 1891 within the anaphylaxis group = 0.001. The results show a difference in the genotype frequency between control and anaphylaxis, suggesting a role for the renin angiotensin system in anaphylaxis manifesting with airway angioedema and cardiovascular collapse.

A double blind randomised placebo controlled pilot study of oral co-trimoxazole in advanced fibrotic lung disease.

BACKGROUND: In 1996, clinical improvement with oral co-trimoxazole was noted in a patient with biopsy proven advanced fibrotic lung disease who was awaiting a lung transplant. Subsequently, 14 patients with end stage fibrotic lung disease also responded to oral co-trimoxazole. This prompted a double blind randomised placebo controlled pilot study in patients with advanced stages of idiopathic interstitial pneumonias (IIP) to objectively measure benefit. PATIENTS: Twenty patients (aged 49-84 years; 11 males) with progressive fibrotic lung disease who had differing subtype diagnosis from CT scans of progressive fibrotic IIP, and showed oxygen desaturation on exertion were selected. METHOD: A detailed assessment of arterial gases, lung function, and progressive shuttle-walking tests combined with oxygen saturation monitoring. Quality of life data was recorded. Randomisation was to co-trimoxazole or identical placebo for 3 months followed by 6 weeks of pulmonary rehabilitation before decoding. Placebo patients received active treatment upon decoding with continued follow up of all patients. MAIN OUTCOME MEASURES: Primary 1. Shuttle walking test. Secondary 2. FVC and quality of life. RESULTS: Active treatment showed a significant improvement in shuttle walking test from 255 to 355 m (p=0.002) (95% CI 200-450) with reduced oxygen desaturations during exercise (p=0.003). FVC improved on treatment (+21%) from median 1.9 to 2.3 L (p=0.05) (95% CI 1.3-3.0) but TLC and DLCO were not significantly changed although stable at 12 months. The MRC 5 Point Dyspnoea Score showed improvement (p=0.05) at 3 months for the active group which was maintained at 12 months. The SGHRQ showed a significant reduction in symptom scores at 12 months (p=0.05). The placebo group showed no significant change in any parameters, but demonstrated identical improvement following oral co-trimoxazole. Serum vascular endothelial growth factor (VEGF) was reduced 50% in the active group at 3 months, but just failed to reach statistical significance. 'Out of study' HRCT scans in 12 patients showed significant reduction in ground glass changes (p=0.05) after 12 months of continuous co-trimoxazole treatment. CONCLUSION: The findings of the pilot study show significant improvements in objective and subjective parameters which fulfil the ATS/ERS (2000) criteria of 'a favourable response to treatment'.

The successful treatment of chylous effusions in malignant disease with octreotide.

Chylous effusions in adults are commonly associated with malignant disease. Although the condition is rare, their occurrence presents a significant management problem. A review of the literature demonstrates the high mortality of this condition in the past from cachexia and infection or after surgical attempts at correction. The first report of somatostatin use in chylous effusions was a decade ago. Since 2000, case reports of successful treatment in infants and neonates with intravenous somatostatin or octreotide have been published. For adults, few reports exist. We describe a case series of seven patients, all with malignancy. In each case, there was a systematic approach to treatment using subcutaneous octreotide and a fat-free diet, resulting in complete resolution of the condition. Although no guidelines are available for the management of chylous effusions, our non-invasive approach avoided lymphangiogram, surgery and allowed early discharge.

Amiodarone - induced pulmonary nodules mimiking metastatic lung disease - investigation by somatostatin radio peptide scanning.

A 61 year old former paramedic presented to A&E complaining of palpitations. He was found to be in atrial fibrillation, which reverted spontaneously to sinus rhythm. A chest x-ray taken at that time showed multiple pulmonary nodules consistent with metastatic malignancy (Figure 1). In the past he had been treated with amiodarone 200mg daily for 6 years following a previous diagnosis of atrial fibrillation, which had been attributed to alcoholic cardiomyopathy. He had discontinued the drug 8 months earlier, after self diagnosing hypotension and bradycardia. A previous chest x-ray, taken before starting amiodarone, was normal.

The pathway study: results of a pilot feasibility study in patients suspected of having lung carcinoma investigated in a conventional chest clinic setting compared to a centralised two-stop pathway.

UNLABELLED: The best chance of cure in non-small cell lung cancer (NSCLC) is surgical resection, but UK rates of 8% compare poorly to 25% in the USA and Europe. Delays in diagnosis in the current UK system may be one reason for such discrepancy. To address this problem we set up a rapid diagnostic system and compared it to the conventional method of investigations in a pilot randomised trial. METHODS: Eighty-eight patients were prospectively enrolled from three District General Hospitals and randomised to either investigation locally or to the rapid system at The Royal Marsden Hospital. The pilot end-points were feasibility and audit of radical treatment rates to enable estimates for patient numbers for the full study. RESULTS: Forty-five and 43 patients were in the central and conventional arms, respectively (65% male, median age 69 years). There was a 4-week improvement in time to first treatment in those in the central arm (P=0.0025) with 13/30 (43%) and 9/27 (33%) patients having radical treatment in the central and conventional arms, respectively. Patients in the conventional arm felt the diagnostic process was too slow (P=0.02) while those in the central arm seemed to have a better care experience (P=0.01). There were significantly less visits to the general practitioner (GP) in the central arm (P=0.02). CONCLUSIONS: This pilot study demonstrates that the full study is feasible but would require the commitment and involvement of a large number of patients and physicians. The results show several advantages to investigations and diagnosis in the central arm, particularly in time to treatment initiation, patient satisfaction and rate of radical treatments. The improved rate of radical treatment could lead to an improved survival rate.

Usefulness of specific immunotherapy in patients with severe perennial allergic rhinitis induced by house dust mite: a double-blind, randomized, placebo-controlled trial.

OBJECTIVES: To evaluate the effectiveness of specific immunotherapy (SIT) in patients with severe house dust mite (HDM)-induced perennial allergic rhinitis using diary cards and objective endpoints. PATIENTS AND METHODS: Thirty-six adult patients were selected with moderate to severe allergic rhinitis due to HDM allergy uncontrolled by regular anti-allergic drugs. Twenty-eight patients completed the study, 22 of these patients also had mild asthma. Subjects were stratified for HDM sensitivity on the basis of their 4-week diary card score and the size of their immediate and late-phase skin reaction to HDM. The groups were well matched for all relevant parameters. Patients were randomized to receive active preparation (Alutard(R)-SQ, ALK, Dermatophagoides pteronyssinus extract) or an identical placebo preparation. Increasing doses were administered until the maintenance dose was reached. This dose was then given once a month for 12 months. RESULTS: Clinical efficacy was evaluated by symptom medication diary cards recorded for 4 weeks after 12 months of continuous treatment and compared with pre-treatment scores. Skin test reactivity was re-measured after 12 months of treatment to HDM, cat dander and codeine phosphate. After 1 year of treatment, the actively treated group showed a 58% reduction in diary card symptom scores (P<0.002) and a 20% reduction in the use of rescue medication. The placebo group had a 32% reduction in symptom scores (P=NS), but no reduction in rescue medication requirements. The active group showed 36% reduction in skin prick test sensitivity to D. pteronyssinus (P=0.006), while the placebo group values were unchanged. Skin reactivity to codeine was unchanged in both groups. No significant adverse reactions to SIT were encountered. CONCLUSIONS: One year of SIT for D. pteronyssinus in patients with poorly controlled rhinitis (+/-mild asthma) produced clinically useful improvement as shown by symptom-medication diary cards and reductions in immediate skin reactions compared with placebo treatment.

Chylous effusions complicating lymphoma: a serious event with octreotide as a treatment option.

Chylous effusions have an identical appearance to milk and occur when the thoracic duct is blocked. Since chyle represents direct absorption of fat from the small intestine lacteals, it is rich in fat, calories, vitamins and immunoglobulins. Drainage of this milk-like fluid from any cavity (chest or abdomen) results in rapid weight loss and profound cachexia. The recognition of this milk-like fluid as chyle is urgent for the implementation of the correct treatment. In adults, lymphoma is one of the commonest malignancies to cause blockages in the thoracic duct. Once the diagnosis is made, conservative treatment with strict dietary adjustment often fails to prevent weight loss or resolve the underlying cause. Since the condition is uncommon, no guidelines exist. Many surgeons recommend early surgical intervention before the patient becomes too weak. Surgery may also fail. We report the case of a 62-year-old man with chylous effusions and a weight loss of 30 kg. The nature of the effusion was unrecognized for the first 16 weeks. Upon diagnosis, dietary adjustment was made and a lymphangiogram organized with a view to surgery. Literature searches revealed two cases in which somatostatin was used after surgical procedures failed. We therefore used octreotide (a synthetic analogue of somatostatin). We report complete resolution of the condition within 72 h leading to the resumption of a normal diet and discharge within 2 weeks.

Grass pollen immunotherapy decreases the number of mast cells in the skin.

BACKGROUND: Allergen injection immunotherapy is effective for summer hay fever and reduces cutaneous sensitivity to grass pollen. OBJECTIVE: We have addressed whether this effect of immunotherapy may be due to a decrease in mast cell numbers in the skin. METHODS: Total mast cells and mast cell subtypes in the dermis were measured by dual immunocytochemistry in 40 adult patients who had received either 'active' grass pollen immunotherapy or placebo injections for 9 months in a double-blind clinical trial. RESULTS: Clinical improvement in hay fever was accompanied by a greater than 10-fold reduction in the immediate cutaneous response to grass pollen (P = 0. 0002) and a sevenfold decrease in mast cell numbers in the skin (P = 0.0001). The number of mast cells after immunotherapy correlated with the clinical response in terms of seasonal symptoms (r = 0.61, P = 0.001) and rescue medication use (r = 0.75, P = 0.0001). Specific double immunostaining showed that the majority of mast cells (greater than 60%) were tryptase/chymase-positive (MCTC) and the remainder tryptase-only (MCT) cells. Following immunotherapy both subtypes were equally reduced. CONCLUSION: One mechanism by which immunotherapy may act is to reduce mast cell numbers with a consequent reduction in immediate allergic sensitivity.

Clinical efficacy of specific immunotherapy to cat dander: a double-blind placebo-controlled trial.

OBJECTIVES: To assess the efficacy of specific immunotherapy with standardized cat dander extract, using objective endpoints and simulated 'natural' exposure to cats. DESIGN: Double-blind, randomized, placebo-controlled study carried out at a UK Allergy research clinic. SUBJECTS: Twenty-eight patients with moderate to severe allergic rhinoconjunctivitis with asthma due to cat allergy. Subjects were stratified for cat sensitivity, cat ownership and asthma, and the groups were well matched for all relevant parameters. MAIN OUTCOME MEASURES: Symptom scores and peak flow rate during and after exposure to cats in a cat-room. Skin tests and conjunctival provocation thresholds. RESULTS: The actively treated group showed a marked reduction in symptoms during the cat exposure (mean score 61.6-17.1; P < 0.001) with no change in the placebo group (64.7 vs 62.1). The active group also showed a reduced peak flow response to cat exposure (mean fall of 85 L/min pretreatment, 29 L/min after treatment, P < 0.005) as well as reductions in conjunctival provocation sensitivity, skin sensitivity to cat extract and skin sensitivity to house dust mite (D.pteronyssinus). Skin reactivity to histamine and codeine were unaltered. No significant adverse reactions were encountered. CONCLUSIONS: Specific immunotherapy seems to be an effective treatment for cat allergy. Allergy to cats is common and often poorly controlled on conventional pharmacotherapy. Although cat allergy has not traditionally been considered as a valid indication for immunotherapy in the UK, it should now be considered as a legitimate treatment, especially for those who are unable to avoid exposure.

Grass pollen immunotherapy inhibits allergen-induced infiltration of CD4+ T lymphocytes and eosinophils in the nasal mucosa and increases the number of cells expressing messenger RNA for interferon-gamma.

BACKGROUND: Grass pollen injection immunotherapy is effective in patients with summer hay fever, although efficacy must be balanced against possible side effects. The mechanism of immunotherapy is unknown but may be related to its ability to inhibit allergen-induced late responses, which are known to be characterized by infiltration of T lymphocytes, eosinophils, and cells with messenger RNA for so-called TH2-type cytokines (IL-4 and IL-5). OBJECTIVE: This study was designed to observe the effect of grass pollen immunotherapy on late nasal responses and associated cellular infiltration and cytokine mRNA expression. METHODS: We performed local nasal provocation with grass pollen (and a control challenge) in 28 patients after a 12-month double-blind, placebo-controlled trial of immunotherapy. Nasal biopsy specimens were obtained at 24 hours and processed for immunohistology and in situ hybridization studies. RESULTS: Grass pollen immunotherapy inhibited allergen-induced immediate (0 to 60 minutes) increases in sneezing (p < 0.02) and nasal blocking (p < 0.01) and late (0 to 24 hours) nasal symptoms (p < 0.05). Immunotherapy also inhibited the associated infiltration of the nasal mucosa by CD4+ T lymphocytes and total (major basic protein-containing) and "activated" (cationic protein-secreting) eosinophils (all p = 0.03). There was a significant (p = 0.04) increase in cells expressing mRNA for interferon-gamma at 24 hours after allergen challenge, which correlated inversely with patients' seasonal symptoms (r = -0.65, p < 0.05) and medication requirements (r = -0.75, p < 0.02) during the pollen season. CONCLUSION: The results suggest that successful grass pollen immunotherapy for summer hay fever may act by inhibiting allergen-induced T lymphocyte and eosinophil recruitment and eosinophil activation in the target organ, possibly through a mechanism involving protective local increases in TH1-type cells.

Grass pollen immunotherapy: efficacy and safety during a 4-year follow-up study.

Grass pollen immunotherapy is effective, although efficacy must be balanced against side-effects. In a double-blind, placebo-controlled trial of 40 adult patients with summer hay fever, immunotherapy with a depot grass pollen extract (Phleum pratense, Alutard SQ) reduced symptoms and medication requirements with an acceptable minimal level of side-effects (31). The original placebo group, as well as the actively treated group, have now received active immunotherapy in an open fashion for a further 3 years. An important question was whether continued injection treatment was accompanied by maintained clinical improvement. By analysis of diary symptoms, rescue medication, and visual analogue scores during the pollen season, we show that efficacy was maintained throughout the 3-4-year study period. Clinical improvement was accompanied by a sustained and marked decrease in immediate conjunctival allergen sensitivity and a further significant decrease in the size of the allergen-induced late cutaneous response. In contrast, an initial decrease in the allergen-induced immediate cutaneous response was not maintained at 3-4 years. Of the patients, 37/40 completed the first year, 33/40 the second year, and 32/40 the third year of treatment. Patients dropped out for reasons other than the outcome of immunotherapy. During a total of 2598 injections, five immediate systemic reactions were observed, all during the induction (not maintenance) phase, and all occurred within 10 min of injection and responded promptly to adrenaline. Grass pollen immunotherapy is effective and safe, provided it is performed on carefully selected patients by trained physicians with immediate access to resuscitative measures.

Rhinitis, sinusitis and the yellow nail syndrome: a review of symptoms and response to treatment in 17 patients.

A total of 17 patients with yellow nail syndrome are described. Their symptoms, age of onset and severity are examined with particular reference to the presence of rhinosinusitis. Fourteen of the patients (83%) suffered severe rhinosinusitis, which pre-dated nail changes in four, coincided with yellow nails in six, and occurred later in the remaining patients. In general, patients responded poorly to conventional medical and surgical treatment, with the exception of functional endoscopic sinus surgery (FESS) which may be of value in these patients. The frequent association of rhinosinusitis with yellow nails may warrant its recognition as part of the syndrome. Careful inspection of the fingernails in all patients presenting with severe rhinosinusitis is warranted.

Influence of grass pollen immunotherapy on cellular infiltration and cytokine mRNA expression during allergen-induced late-phase cutaneous responses.

We have studied the influence of grass pollen immunotherapy on cellular infiltration and cytokine mRNA expression during allergen-induced late-phase cutaneous responses. In a double-blind, placebo-controlled trial of immunotherapy in 40 adult hay fever sufferers, clinical improvement was accompanied by a decrease in the size of the late-phase skin response. When the immunotherapy-treated group was compared with the placebo group, analysis of skin biopsies obtained 24 h after intradermal allergen revealed a significant reduction in the number of infiltrating CD3+ (P = 0.04) and CD4+ (P = 0.009) cells and a trend for a decrease in EG2+ eosinophils (P = 0.08). Treatment did not influence allergen-induced recruitment of CD8+ cells, neutrophils, or macrophages. Unexpected increases in expression of CD25 (P = 0.006) and HLA-DR (P = 0.007) were observed in the actively treated group. In situ hybridization using a panel of riboprobes demonstrated "TH2-type" (IL-4, IL-5) cytokine mRNA responses in both groups of patients. In contrast, significant hybridization for IL-2 (8/16 patients, P = 0.02) and for interferon-gamma (6/16 patients, P = 0.04) was observed only in the actively treated group. These findings indicate that immunotherapy is associated with suppression of allergen-induced CD4+ T lymphocyte infiltration, but among the cells that are recruited, there is upregulation of CD25 and HLA-DR. At least in this model, immunotherapy does not appear to affect expression of TH2-pattern cytokines in response to allergen exposure, but expression of mRNA for Th1-type cytokines was enhanced in half of the patients. The results support the view that immunotherapy may possibly be working through induction of T cell tolerance.

Immunohistology of the nasal mucosa following allergen-induced rhinitis. Identification of activated T lymphocytes, eosinophils, and neutrophils.

We have studied the immunohistology of the nasal mucosa in allergen-induced rhinitis. Sixteen grass pollen-sensitive patients were challenged twice by randomly allocated allergen or control solutions applied on filter paper disks to the inferior turbinate. All had immediate nasal responses, but late-phase responses were equivocal and only evident as nostril blockage. When cell counts in the nasal submucosa were compared with control values 24 h after allergen, there were no changes in CD45+ (total leukocytes), CD3+, or CD8+ cells. Significant increases were found in the numbers of CD4+ T-helper cells (p less than 0.05) and CD25+ [interleukin-2 receptor (IL-2R+)] cells (p less than 0.02). Increases in eosinophils (anti-major basic protein, p less than 0.01) and neutrophils (antineutrophil elastase, p less than 0.01) were also observed. There were increases in tissue macrophages and HLA-DR-positive immunostaining and a reduction in mast cells (tryptase positive), but none of these changes was statistically significant. No significant changes in epithelial thickness, cross-sectional area, or integrity were observed. There was a significant correlation between CD4+ and CD25+ cells (r = 0.61, p less than 0.01) but not between macrophages and CD25+ cells (r = 0.18). The changes in the nasal submucosa were not merely a reflection of alterations in circulating cell populations since it was shown that a significant increase in the lymphocyte CD4/CD8 ratio (p less than 0.05) was observed in nasal biopsies but not in peripheral blood after allergen challenge.(ABSTRACT TRUNCATED AT 250 WORDS)

Preferential messenger RNA expression of Th1-type cells (IFN-gamma+, IL-2+) in classical delayed-type (tuberculin) hypersensitivity reactions in human skin.

We recently established that the allergen-induced late-phase cutaneous reaction in atopic subjects was associated with high mRNA expression for the cytokine gene cluster IL-3, IL-4, IL-5, and granulocyte/macrophage-CSF (GM-CSF), compared with IFN-gamma and IL-2, suggesting that allergic skin reactions contained the equivalent of murine Th2 cells. We now show that, in humans, classical delayed-type hypersensitivity is associated with cells preferentially expressing a Th1-type cytokine profile. Cryostat sections from skin biopsies from 24-h tuberculin reactions in 10 nonatopic subjects were hybridized with 35S-labeled RNA probes and processed by using in situ hybridization. On the whole, tuberculin biopsies showed preferential expression of mRNA encoding IFN-gamma and IL-2, although in some cases mRNA expression for IL-3, IL-4, IL-5, and GM-CSF was also observed. Biopsies from diluent control sites gave only occasional signals. The difference in the number of cells expressing mRNA in the diluent compared with tuberculin sites was statistically significant for IL-2 and IFN-gamma (p less than 0.01) but not for IL-3, IL-4, IL-5, and GM-CSF. These results suggest that cells infiltrating the site of the 24-h tuberculin reaction preferentially transcribe mRNA encoding IFN-gamma and IL-2, supporting the hypothesis that delayed-type hypersensitivity is associated with preferential activation of cells having a cytokine profile similar to the murine Th1 subset.

Cytokine messenger RNA expression for IL-3, IL-4, IL-5, and granulocyte/macrophage-colony-stimulating factor in the nasal mucosa after local allergen provocation: relationship to tissue eosinophilia.

Tissue eosinophilia is characteristic of human atopic allergic inflammation, although the mechanism is largely unknown. In this study we test the hypothesis that eosinophil infiltration during allergen-provoked rhinitis in hayfever sufferers may occur as a consequence of activation of a population of cells having a characteristic cytokine profile equivalent to the murine Th lymphocyte Th2 subset. Biopsies of the nasal inferior turbinate were obtained from 10 grass pollen-sensitive patients 24 h after local nasal provocation with allergen and after a control challenge with the allergen diluent. Biopsies were divided into two and subsequently processed for in situ hybridization using 35S-labeled RNA probes for selected cytokines and for immunohistology using an eosinophil granule mAb (EG2) which recognizes secreting eosinophils. At allergen-challenged sites compared with control sites there were significant increases in mRNA+ cells for IL-3 (p less than 0.04), IL-4 (p = 0.01), IL-5 (p = 0.02) and granulocyte/macrophage-CSF (p = 0.03). In contrast, only occasional hybridization signals were observed for IL-2 and IFN-gamma at both allergen and control sites. After allergen there was an increase (p = 0.01) in EG2+ eosinophils and significant correlations were observed between EG2+ cells and mRNA expression for "Th2-type" cytokines, particularly IL-5 (r = 0.90, p less than 0.0001). These results demonstrate that recruitment of eosinophils during human allergen-induced rhinitis is associated with cells expressing mRNA for IL-3, IL-4, IL-5, and granulocyte/macrophage-CSF.