Extracellular deposition of eosinophil and neutrophil granule proteins in the IgE-mediated cutaneous late phase reaction

Intradermal injection of allergens in sensitive subjects produces an IgE-dependent prolonged inflammatory reaction, the late phase reaction (LPR). Histologically, eosinophils are present in the LPR but are not as numerous as neutrophils or mononuclear cells. We determined whether extracellular deposition of eosinophil and neutrophil granule proteins occurs in the LPR by immunofluorescent localization of eosinophil granule major basic protein (MBP), eosinophil-derived neurotoxin (EDN), and neutrophil elastase. Before intradermal challenge, eosinophils and neutrophils were present only in blood vessels, and MBP, EDN, and elastase were localized to cells. At 15 minutes, small amounts of MBP, EDN and elastase were found outside of cells in focal areas. By 1 to 3 hours, MBP, EDN and elastase were extensively deposited throughout the dermis in a granular and diffuse manner; these deposits persisted up to 56 hours. Both actively and passively sensitized subjects showed similar MBP and elastase deposition. Skin sites passively sensitized by sera depleted of IgE showed essentially no MBP or elastase deposition. Electron microscopy showed degenerating eosinophils and free eosinophil granules in the dermis. Mast cell numbers diminished during the LPR when extracellular eosinophil and neutrophil granule protein deposition was maximal. These results demonstrate that striking dermal eosinophil and neutrophil granule protein deposits are prominent features of the cutaneous LPR, are IgE-dependent and precede the maximal clinical expression of the LPR. The possible significance of these findings in the pathophysiology of the LPR is discussed.     

Eosinophil inflammation of nasal polyp tissue: relationships with matrix metalloproteinases,tissue inhibitor of metalloproteinase-1, and transforming growth factor-beta1

Eosinophil and mast cell infiltrations are consistent findings in nasal polyp tissue. Previous studies have shown that matrix metalloproteinases (MMPs) may be involved in eosinophil infiltration in airway mucosa of asthmatic patients, and that transforming growth factor-beta1 (TGF-beta1) induces extracellular matrix deposition in nasal polyp tissue. The aim of this study was to evaluate the role of MMPs and tissue-inhibitor of metalloproteinase-1 (TIMP-1) in association with TGF-beta1, eosinophils and mast cell activation in nasal polyp tissue. Nasal polyp tissues from 20 patients who underwent polypectomies were collected and prepared into tissue homogenate. Eosinophil cationic protein (ECP) and tryptase levels were measured by CAP system (Pharmacia, Sweden). MMP-2, MMP-9, TIMP-1 and TGF-beta1 levels were measured by enzyme-liked immunosorbent assay. MMP-2 was the predominant form of MMPs, followed by MMP-9 and TIMP-1. There were significant correlations between ECP, and MMP-9, MMP-2, TGF-beta1 and tryptase, but not with TIMP-1. Significant correlations were noted between tryptase, and MMP-2, MMP-9, and TGF-beta1, but not with TIMP-1. Close correlations were noted between TGF-beta1, and MMP-9 and MMP-2, but not with TIMP-1. MMP-2, MMP-9, and TGF-beta1 may contribute to eosinophil and mast cell migrations into nasal polyp tissue.     

Sequestration of eosinophil major basic protein in human mast cells.

Previous studies showed that lung and skin mast cells do not contain eosinophil granule major basic protein (MBP). However, MBP has been localized by immunofluorescence to mast cells from a recently established human mast cell line. Analysis of MBP in human mast cell-1 cell lysates by radioimmunoassay showed immunochemical similarity to eosinophil MBP as judged by comparison of dose-response regression lines. Based on these findings and other new information about mast cell heterogeneity, we tested whether mast cells contain MBP. Mast cells were preserved in Carnoy's fixative and were identified by staining with rhodamine-conjugated avidin or for chloroacetate esterase or aminocaproate esterase activity. MBP was localized by immunofluorescence to mast cells in 6 of 7 nasal polyps, 4 of 4 ileal tissue specimens, and 12 of 14 cutaneous mastocytosis specimens. Furthermore, by immunoelectron microscopy MBP was localized to mast cell granules in cutaneous mastocytosis lesions. In contrast, normal skin mast cells preserved in Carnoy's fixative did not contain MBP. After injection of MBP into normal skin and fixation in Carnoy's fluid, mast cells became MBP-positive within 3 minutes, suggesting that endocytosis of MBP by mast cells had occurred. These results suggest that human mast cells in several tissues may sequester toxic eosinophil proteins by endocytosis.     

Nodules, eosinophilia, rheumatism, dermatitis and swelling (NERDS): a novel eosinophilic disorder

This study presents the clinical and laboratory findings of a novel syndrome associated with eosinophilia. Two young women presented with marked eosinophilia, and large, non-tender compressible articular nodules arising from the tenosynovium of extensor tendons, dermatitis, episodic swelling of the hands and/or feet and pain in adjacent muscles and joints. Tissue specimens were examined by routine haematoxylin and eosin staining, immunofluorescent staining for eosinophil granule major basic protein (MBP) and rhodamine-avidin or tryptase staining for mast cells. Plasma levels of MBP and eosinophii-derived neurotoxin (EDN) were quantilated by immunoassay. The first patient presented in 1967 at the age of 20 and had, in addition to nodules and eosinophilia, dermographism, recurrent episcleritis and axillary urticaria. Biopsy of a nodule showed lenosynovitis with necrotizing granulomas, non-specific vasculitis, eosinophils and eosinophil degranulation as shown by extracellular deposition of eosinophil granule MBP. Her symptoms responded to low-dose, alternate-day predni-sone and have remained quiescent over the past 15 yr. The second patient presented in 1990 at the age of 28 with generalized pruritic dermatitis for 15 yr, eosinophilia for 2 yr. subcutaneous nodules and non-limiting pain in several joints. Biopsy of a nodule showed chronic mild tenosynovitis, numerous eosinophils and extracellular deposition of M BP. She remains untreated. Serum IgE values and plasma levels of M BP and EDN were elevated in both patients; mast cells were numerous in their synovial tissue. Based on their clinical courses, these patients reveal the existence of a distinctive, relatively benign eosinophilic disorder with good long-term prognosis.     

Human eosinophils induce histamine release from antigen-activated rat peritoneal mast cells: a possible role for mast cells in late-phase allergic reactions

BACKGROUND: Mast cells and eosinophils are believed to interact during the late and the chronic stages of allergic inflammation. OBJECTIVE: In this study we investigated whether eosinophils can cause activation and consequent histamine release of already challenged mast cells, a situation likely to take place during the allergic late-phase reaction. METHODS: Rat peritoneal mast cells presensitized with IgE anti-dinitrophenol-human serum albumin and challenged by dinitrophenol-human serum albumin or compound 48/80 were incubated with either eosinophil sonicate or major basic protein (MBP). Eosinophils were purified from the peripheral (>98%) blood of mildly allergic patients. Heparin and pertussis toxin and different extracellular Ca(2+) concentrations were used to modulate mast cell reactivation by MBP. Histamine release was assessed as a marker of mast cell activation. RESULTS: IgE-challenged mast cells were sensitive to reactivation induced by eosinophil sonicate and MBP. Reactivation was not cytotoxic for the mast cells. Mast cells previously challenged with compound 48/80 did not respond to subsequent MBP activation. Furthermore, heparin and pertussis toxin both inhibited mast cell reactivation induced by MBP. The ability of eosinophil sonicate and MBP to activate mast cells was not significantly affected at the different Ca(2+) concentrations. CONCLUSIONS: In summary, we have shown a direct activating activity of eosinophils, partially due to MBP, toward IgE-challenged and immunologically desensitized mast cells. This suggests that in vivo mast cells can be reactivated during a late-phase reaction to release histamine by a non-IgE-dependent mechanism.     

Tryptase in nasal fluid is a useful marker of allergic rhinitis

Tryptase is a mast cell-specific marker of degranulation. To investigate the possible diagnostic value of tryptase in allergic rhinitis, we measured the levels in both serum and native nasal fluid with a sandwich RIA-assay (Pharmacia). Twenty-three allergic patients and five patients with chronic ethmoidal sinusitis were included. Eighteen of the 23 allergic patients were tested within the pollen season or had perennial rhinitis; the remainder were tested at least 1 month out of the pollen season. None of the patients had detectable serum tryptase (>0.1 ng/ml). Also patients with chronic ethmoidal sinusitis showed no tryptase in nasal fluid. One of seven allergic patients tested out of season had slightly increased nasal tryptase of 1.8 ng/ml. In patients with active nasal allergy, the tryptase in nasal fluid ranged from 6.4 ng/ml to 640 ng/ml with a mean of 101 ng/ml and SD 173. These results show a clear distinction between active and non-active nasal allergy and other non-mast-cell-related nasal disease. Further, nasal tryptase release by natural allergen exposure is even higher than that observed in allergen challenge tests.     

Deposition of eosinophil granule proteins precedes blister formation in bullous pemphigoid. Comparison with neutrophil and mast cell granule proteins.

Eosinophils, neutrophils, and mast cells have all been implicated in the pathogenesis of bullous pemphigoid (BP). To comparatively characterize the involvement of these cells in BP, 10 lesional skin biopsy specimens were identified retrospectively and studied for tissue localization of eosinophil, neutrophil, and mast cell granule proteins. Subsequently, multiple skin biopsies of lesions in various developmental stages were obtained from 3 patients with untreated BP. Involved and uninvolved skin specimens were also obtained from 2 patients. Using indirect immunofluorescence, retrospectively identified lesions showed eosinophils and extracellular granule protein deposition prominently in areas of blistering. Evolving lesions showed eosinophil granule protein deposition in all stages but was most marked in early erythematous and prebullous (urticarial) lesions and was minimal in uninvolved skin. Vascular cell adhesion molecule-1, E-selectin, and P-selectin were detected on vessels and very late activation antigen-4 was detected on mononuclear cells and eosinophils by immunoperoxidase staining of lesions. Eosinophil granule proteins were increased in the peripheral blood, urine, and blister fluid. Blister fluids caused increased eosinophil survival that was inhibited by antibodies to interleukin-5 and interleukin-3. Although neutrophil and mast cell infiltration was observed, extracellular granule protein deposition from these cells was minimal except in two specimens. These results demonstrate that eosinophils infiltrate and deposit granule proteins early in the development of BP lesions, that eosinophil-activating cytokines are present in blister fluid, and that eosinophil-selective adhesion molecules are present. These studies strongly support a role for eosinophils in blister formation in BP.     

Allergic mucin with and without fungus: a comparative clinicopathologic analysis.

CONTEXT: Allergic mucin, a lamellated collection of inspissated inflammatory debris, has been a hallmark of allergic fungal sinusitis. While its identification is a clue for pathologists to search for fungi, and directs clinicians toward specific therapy and follow-up, recent reports describe cases with allergic mucin but without concomitant fungus. The absence of such organisms in otherwise typical allergic mucin brings into question the role of fungi in allergic fungal sinusitis. OBJECTIVES: To study clinical and pathologic differences between patients with allergic mucin in surgical nasal resection specimens and to elucidate the role of fungus in allergic sinusitis. DESIGN: Patients with histologic evidence of allergic mucin, with and without fungus, were identified and retrieved from the surgical pathology files of a tertiary-care institution. The patients were separated into 2 groups for analysis, and their clinical and pathologic findings were reviewed and compared. SETTING: Tertiary-care institution. PATIENTS: All patients who underwent sinus mucosal resection between 1992 and 1998. RESULTS: Clinical presentation and radiographic findings were similar in both groups. Incidence, age, and gender distribution were similar to data reported previously. However, the amount of allergic mucin was much greater in the group with fungus than in the group without fungus, which to our knowledge is an unreported observation to date. CONCLUSION: The presence of allergic mucin is not unique to allergic fungal sinusitis, but rather is the result of a process that could have other etiologies. While perhaps not always causative to the disease, the fungus continues to fuel the process and is likely an entrapped bystander. Allergic fungal sinusitis is more appropriately termed allergic mucinous sinusitis or eosinophilic mucinous rhinosinusitis.     

Allergic Bipolaris sinusitis: clinical and immunopathologic characteristics

Allergic Aspergillus sinusitis was first reported in 1983. We present the first three cases of allergic fungal sinusitis caused by the black fungus Bipolaris spicifera. The patients were young, atopic, and immunocompetent. All three patients demonstrated pansinusitis with nasal polyps and underwent multiple surgical procedures. Pathologic features included a characteristic mucoid exudate containing eosinophils, Charcot-Leyden crystals, and fungal hyphae. In two cases there was bony erosion revealed by computed tomography scan but no histologic evidence of direct fungal invasion into the mucosa or bony trabeculae. Immunologic features, including total eosinophil count, total serum IgE, immediate and late-phase skin response to B. spicifera, serum precipitins, and specific IgE and IgG to B. spicifera, are described. B. spicifera is a previously unrecognized cause of allergic fungal sinusitis that may be an underdiagnosed disorder. This diagnosis should be considered in atopic patients with nasal polyps and pansinusitis unresponsive to conventional medical therapy. Diagnostic criteria include characteristic histologic allergic mucin, culture identification of fungus, positive immediate cutaneous reactivity to fungal extract, positive serum precipitins, and elevated specific IgE and IgG antibodies.     

Immunohistochemical characterization of the cellular infiltrate in airway mucosa of toluene diisocyanate (TDI)-induced asthma: comparison with allergic asthma.

Toluene diisocyanate (TDI) is the most prevalent agent in occupational asthma (OA) in Korea. The immuno-pathologic mechanism for TDI-induced bronchoconstriction remains to be clarified. We studied the immunohistochemical finding of inflammatory cells in bronchial mucosa in subjects with TDI-induced asthma. Fiberoptic bronchial biopsy specimens were obtained from nine subjects with TDI-induced asthma. Six allergic asthma sensitive to house dust mite were enrolled as controls. Bronchial biopsy specimens were examined by immunohistology with a panel of monoclonal antibodies to mast cell tryptase (AA1), secretary form of eosinophil cationic protein (EG2), pan T-lymphocyte (CD3) and neutrophil elastase (NE). There was a significant increase in the number of AA1+, EG2+ and NE+ cells in TDI-induced asthma compared to those of allergic asthma (p=0.02, p=0.04, p=0.03, respectively). No significant differences were observed in the number of CD3+ cells (p=0.27). These findings support the view that neutrophil recruitment together with eosinophil and mast cell, may contribute to the bronchoconstriction induced by TDI.     

In vitro diagnosis of chronic nasal inflammation

BACKGROUND: Differential diagnosis of chronic nasal inflammation is insufficient when based solely on clinical examination and radiography of paranasal sinuses. Patients complain about more or less similar symptoms. Activation of mast cells and eosinophils is pivotal in nasal inflammation. OBJECTIVE: To compare tryptase and eosinophilic cationic protein (ECP) in nasal secretions in different forms of chronic nasal inflammation and to establish norm values. METHODS: The study included 1710 patients presenting with nasal complaints. Nasal secretions were gained by the cotton wool method and analysed for tryptase, as a marker of mast cell activation, and for ECP, as a marker of tissue eosinophilia and activation. Patients were grouped according to their diagnosis: chronic, non-allergic rhinosinusitis (sinusitis, n=194), non-allergic nasal polyposis (polyposis, n=138), non-allergic rhinitis with eosinophilia syndrome (NARES, n=198), isolated perennial allergic rhinitis (AR) (n=126), isolated seasonal AR (n=132), and patients allergic to both, seasonal and perennial allergens (n=193). Seven hundred and twenty-nine patients with nasal complaints due to a deviated septum and without any nasal inflammation served as controls. RESULTS: Nasal tryptase was highly significantly (P<0.001) elevated in polyposis, NARES, and in AR. ECP was highly significantly (P<0.001) elevated in all groups of patients suffering from chronic nasal inflammation. Based on our data and method we established norm values (95% confidence interval of mean value) for nasal tryptase in healthy adults, ranging from 12.0 to 18.7 ng/mL and for ECP ranging from 84.4 to 102.6 ng/mL. CONCLUSION: Mast cells and eosinophils are involved in non-allergic and allergic forms of chronic nasal inflammation. We established an in vitro assay for tryptase and ECP in nasal secretions and defined norm values based on our data and method. In vitro measurement of biological markers in nasal secretions provides important information for differential diagnosis and therapeutic strategies of chronic nasal inflammation.     

Airway mast-cell activation in asthmatics is associated with selective sputum eosinophilia

BACKGROUND: Tryptase is a serine endoprotease selectively released from mast cells. Although mast cells are known to be activated after experimental allergic provocation, their role in naturally occurring asthma is still debated. METHODS: We have investigated the levels of tryptase in the whole induced sputum collected from 51 asthmatics (31 atopic and 20 intrinsic) seen in our outpatient clinic and 22 normal nonatopic healthy volunteers. Tryptase was measured by a new immunoassay based on B12 monoclonal antibody recognition of total tryptase (UniCAP System, Pharmacia) with a sensitivity of 1 ng/ml. RESULTS: While being below the threshold of detection in all normal volunteers, tryptase was detectable in the sputum from 9/51 asthmatics (18%) including five atopic and four intrinsic asthma cases. In these patients, among whom three were asymptomatic asthmatics, the values ranged between 1 and 6.1 ng/ml. The asthmatics with detectable sputum tryptase had greater sputum eosinophil counts (P<0.05) but lower neutrophil counts (P<0.05) than those in whom tryptase was undetectable. When compared to control subjects, asthmatics without tryptase had still greater eosinophil counts (P<0.0001) but also raised neutrophil counts (P<0.05). No significant difference could be found between asthmatics with tryptase and those without tryptase with respect to the age, the baseline lung function, the methacholine bronchial responsiveness, and the frequency of treatment with inhaled steroids. CONCLUSIONS: With the UniCAP System, tryptase was detectable in the sputum from 18% of asthmatics irrespective of atopy and current symptoms. Asthmatics with tryptase appeared to have a selective increase in sputum eosinophil counts while those without tryptase displayed a mixed sputum granulocyte infiltration with raised eosinophil and neutrophil counts.     

变应性真菌性鼻窦炎临床病理分析

目的 探讨变应性真菌性鼻窦炎(AFS)的临床病理特征,提高对AFS的认识和病理诊断水平.方法 回顾并分析首都医科大学附属北京同仁医院2002-2006年36例AFS的临床病理和影像学资料,应用阿尔辛蓝-过碘酸雪夫(AB-PAS)、环六亚甲基四胺银(GMS)特殊染色及黏蛋白5B(MUC5B)免疫组织化学(SP法)染色标记真菌,同时选取AFS新鲜活检组织lO例进行透射电镜观察.结果 36例AFS中,男21例,女15例,发病年龄11～53岁.多具有变应性疾病病史.CT平扫示受累的鼻窦充满软组织影,伴斑片状高密度影,窦壁骨质可出现压力性骨破坏.实验室检查:一种或多种真菌抗原皮试阳性(31/36);血清学检查总IgE和(或)真菌特异性lgE增高(20/36);外周血嗜酸性粒细胞数增多(23/36).真菌培养10例阳性.组织病理学:大体典型病变为黏稠的"油灰样"分泌物,镜下为特征性的"嗜酸性黏蛋白",AB-PAS及GMS染色、MUC5B免疫组织化学染色真菌均着色.透射电镜可见嗜酸性粒细胞脱颗粒现象.结论 "嗜酸性黏蛋白"是AFS最具特征性的病理学表现,建议采用AB-PAS、GMS特殊染色及MUCSB免疫组织化学染色等多种方法 联合标记真菌;需对临床症状、影像学特点、实验室检查及病理学表现等多个方面进行综合判断以得出正确诊断.     

The increased number of epithelial mast cells in nasal polyps and adjacent turbinates is not allergy-dependent

Respiratory epithelial mast cells are an expression of airway inflammatory processes. Nasal epithelial mast cells are known to be increased in allergic rhinitis and have now been examined in patients with nasal polyps. Metachromatic cell counts (mean +/- standard error) expressed as the sum of large mast cells, atypical mast cells and basophils in epithelial scrapings of the inferior turbinates, assessed after Carnoy's fixation and toluidine blue staining (pH 0.5), were 37.5 +/- 29 in non-allergic normal control subjects (n = 11), 435 +/- 130 in polyp patients who were allergic (n = 18), and 699 +/- 267 in polyp patients who were not allergic (n = 8). Metachromatic cell counts in epithelial scrapings obtained in vivo from nasal polyps of allergic patients (n = 8) were 1769 +/- 962, and 2308 +/- 1544 from polyps of non-allergic patients (n = 5); metachromatic counts were 2089 +/- 633 in epithelial scrapings from excised polyps of allergic patients (n = 14) and 2214 +/- 640 from polyps of non-allergic patients (n = 13). It is concluded that the number of metachromatic cells in the epithelium of nasal polyps and the adjacent nasal mucosa is elevated compared with normal nasal epithelium and the increased number does not depend upon allergy.     

Allergic fungal sinusitis due to Curvularia lunata

The clinical and pathologic features of allergic fungal sinusitis caused by Curvularia lunata, as seen in two patients, are described. The findings are identical to those of allergic aspergillus sinusitis. Patients have allergies, nasal polyposis, and, occasionally, eosinophilia. Radiographs show opacification of multiple sinuses without bone destruction. Surgical specimens consist of polyps and inspissated, mucoid material. Diagnostic microscopic features, termed "allergic mucin," include eosinophils, numerous Charcot-Leyden crystals, and hyphae embedded in pools of mucus. The recognition of allergic mucin may be impeded by extensive degranulation and fragmentation of the eosinophils. In addition, the fragments of mucin exhibit large, poorly stained central areas, probably due to incomplete penetration by the fixative. Eosinophils are easier to recognize in well-fixed areas. Electron microscopy, though not of diagnostic necessity, confirms the eosinophilic nature of the infiltrate. It is important that surgical pathologists recognize this distinctive clinicopathologic entity and recommend appropriate cultures.     

Mast cell tryptase activates peripheral blood eosinophils to release granule-associated enzymes

BACKGROUND: Mast cells and eosinophils are important effector cells in asthma. Understanding their interactions is essential for studying asthma pathophysiology. Inflammatory mediators released from mast cells, such as arachidonic acid metabolites, TNF and IL-5, are important in eosinophil biology. However, little is known about the effects of mast cell-specific mediators, such as tryptase, on eosinophils. Our objective was to investigate the effects of mast cell tryptase on human peripheral blood eosinophils. METHODS: Peripheral blood eosinophils isolated from asthmatic individuals were activated using various concentrations of tryptase- and protease-activated receptor-2 (PAR-2)-activating peptides (PAR-2 AP). Eosinophil activation was evaluated by the release of granule mediators, superoxide release, estimation of eosinophil survival, changes in intracellular Ca2+ concentration and mitogen-activated protein kinase activation. RESULTS: Tryptase induced the release of eosinophil peroxidase and beta-hexosaminidase from peripheral blood eosinophils but had no effect on RANTES release. Eosinophils isolated from two thirds of our donors responded to tryptase, while the remainder appeared not to respond. Release of granule mediators was dependent on tryptase enzymatic activity. To identify the mechanism of eosinophil activation by tryptase, we studied the expression of PAR-2 by eosinophils and its function. Using RT-PCR, we amplified PAR-2 from eosinophils. However, flow cytometry failed to detect significant PAR-2 expression on the surface of eosinophils. The PAR-2 AP SLIGRL-NH2 did not induce eosinophil activation by any of the methods we employed. CONCLUSION: Our data indicate that mast cell tryptase may affect eosinophil activation status independently of PAR-2.     

Seasonal allergic conjunctivitis is accompanied by increased mast cell numbers in the absence of leucocyte infiltration

Background Seasonal allergic conjunctivitis (SAC) is the most common allergic disease to affect the eye. occurring alone or in association with allergic rhinitis. Infiltration with mast cells and eosinophils is characteristic of the chronic forms of allergic conjunctivitis such as vernal and atopic keratoconjunctivitis. and these cell types also contribute significantly to allergic inflammation in the skin. Indirect evidence for a similar pattern of cellular events in SAC comes from studies which demonstrate raised eosinophil and neutrophil numbers in conjunctival scrapings and elevated levels of mast cell tryptase in tears following allergen challenge. Objective To directly characterize the inflammatory cell infiltrate in SAC and to determine its clinical relevance. Methods We employed specific immunohistochemical staining to count masi cells, eosinophiis and neutrophiis in the conjunctival epithelium and lamina propria of eight atopic patients with SAC in, and 12 SAC patients out of the hay fever season. Sixteen patients with no history of ocular allergy were used as control subjects. Results Mast cells were absent from normal epithelium. During the pollen season median mast cell numbers in the lamina propria were found to be increased by 6I'J(in patients with SAC compared with normals (P= 0.012). Eosinophils were found in the lamina propria in less than half of the symptomatic patients with SAC and in only three patients were eosinophils present in the epithelium. The neutrophil numbers in the lamina propria of patients with SAC tended to be higher than normals but these changes did not reach statistical significance. Conclusion Conclusion These data based on the direct assessment of conjunctival tissue provide evidence that symptoms occur in SAC in the absence of detectable recruitment of eosinophils or neutrophils. This suggests that this disorder is related to mast cell-mediated changes.     

Localization of human eosinophil granule major basic protein, eosinophil cationic protein, and eosinophil-derived neurotoxin by immunoelectron microscopy

By utilizing the colloidal gold particle technique, we localized eosinophil granule major basic protein, eosinophil cationic protein (ECP), and eosinophil-derived neurotoxin (EDN) in human nasal polyp sections by immunoelectron microscopy. Sections stained with affinity chromatography purified rabbit anti-human major basic protein, and subsequently with gold colloidal particle-goat anti-rabbit IgG, showed gold particles predominantly within granule cores, and not within other eosinophil organelles, plasma cells, mast cells, lymphocytes, or neutrophils. Sections stained with anti-ECP or anti-EDN showed gold particles concentrated over the granule matrix with fewer particles centrally. Control sections treated with preimmunization sera showed no staining of cells or organelles. These results verify the localization of major basic protein to the crystalloid core of the human eosinophil granule and show that ECP and EDN reside in the granule matrix. This technique provides a means of accurately locating the sites of major basic protein, ECP, and EDN deposition and thus of identifying eosinophil degranulation patterns in human disease.     

Deposition of eosinophil granule major basic protein onto microfilariae of Onchocerca volvulus in the skin of patients treated with diethylcarbamazine

We investigated the association between eosinophil degranulation, as evidenced by the deposition of granule major basic protein (MBP), and the killing of microfilariae of Onchocerca volvulus in vivo following treatment with diethylcarbamazine (DEC). Utilizing an immunofluorescence procedure for the cellular and extracellular localization of eosinophil MBP in formalin-fixed, paraffin-embedded tissues, we studied skin biopsies from onchocerciasis patients before and during treatment with topically or orally administered DEC. Before DEC, there was little or no inflammatory response in either dermis or epidermis and microfilariae were essentially intact. Immunofluorescent staining for MBP revealed some filamentous fluorescence associated with dermal collagen fibers, very few eosinophils, and no fluorescence in association with intact microfilariae. In contrast, during treatment with DEC, immunofluorescent staining for MBP revealed extensive eosinophil infiltrates in both dermis and epidermis with numerous intraepidermal eosinophil abscesses containing degenerating microfilariae. An intense extracellular immunofluorescence for MBP surrounded degenerating microfilariae in the dermis and epidermis in both the presence and absence of eosinophil infiltrates as early as 4.5 hours after starting therapy. Many intact nondegenerating microfilariae were also present, but they did not show immunofluorescent staining for MBP nor a surrounding inflammatory infiltrate. The results show that immediately following administration of DEC, eosinophils localize and degranulate around microfilariae in the skin and release granule MBP onto or in close proximity to the parasite's surface. Because of the striking association between eosinophil localization, degranulation, and deposition of MBP onto microfilarial surfaces, and the degeneration of microfilariae in the skin, these observations support the hypothesis that the eosinophil, through helminthotoxic granule proteins such as MBP, damages the microfilariae of O. volvulus.     

Myeloperoxidase and interleukin-8 levels in chronic sinusitis

We have recetitly phenotyped inflammation iti tion-infectious allergic and non-allergic chronic maxillary sinusitis using sinus biopsies and lavage fluids. In this first paper, we have concentrated our work on the eosinophil, T cell, mast cell and macrophage infiltrates. However, many unresolved questions remain and particularly the role of neutrophils needed to be addressed. In the present study, we focused on the neutrophilic inflammation: myeloperoxidase (MPO) and interleukin-8 (IL-8) were measured by immunoassays and neutrophils were enumerated by conventional staining in the sinus lavage fluids of 16 patients with chronic sinusitis and six control subjects. Both MPO and IL-8 levels were significantly higher in patients than in controls (P < 0.01 and 0.005, respectively). There was a significant correlation between MPO levels and neutrophil numbers, and between MPO and IL-8 levels in the sinus lavage fluid (P < 0.0001, Spearman rank correlation). The presence of high levels of IL-8 in the lavage fluids of patients suffering from chronic sinusitis, levels which correlate with those of MPO, suggests that this cytokine may activate neutrophils in this chronic disease.