Preferential infiltration by activated eosinophils in allergic sinusitis

Histopathological evaluation of chronic rhinosinusitis: a critical review

BACKGROUND

Chronic rhinosinusitis (CRS) consists of a constellation of symptoms, including facial pressure/pain, hyposmia, rhinorrhea, and nasal congestion. On histopathological evaluation, the disease can be divided into pathophysiologically distinct subgroups. This study systematically reviews the literature regarding the unique histopathological findings of the various subtypes of CRS to determine the potential diagnostic value of performing tissue analysis of CRS specimens beyond routine hematoxylin and eosin (H&E) staining.

METHODS

A PubMed search was untaken to identify articles that evaluated the histopathological features of CRS. Six hundred fifty-four relevant articles were identified and after application of specific exclusion criteria, 71 articles were further reviewed in detail.

RESULTS

All articles included analysis of tissue samples from in-office biopsies or intraoperative specimens of patients who underwent sinus surgery. CRS was often further divided into subgroups and compared with each other and with a control group. The subgroups included CRS with and without nasal polyps, asthmatic and nonasthmatic patients, and with and without eosinophilia. Distinct inflammatory mediators were found for the different subgroups. Twenty-eight articles evaluated these inflammatory markers for their potential value as prognostic indicators.

CONCLUSION

CRS is a heterogeneous disease based on its histopathological findings. Information that is obtainable from light microscopy, but typically goes unreported, can serve as valuable prognostic indictors. However, routine H&E staining is suboptimal in distinguishing among the various subgroups of CRS. Assessment of specific inflammatory mediators in sinus mucosa specimens may help provide prognostic information and guide more tailored treatment for the individual patient.

Mucosal eosinophils and l-selectin ligands are associated with invasive and noninvasive sinus surgery outcomes

BACKGROUND

Chronic rhinosinusitis (CRS) is characterized by persistent inflammation of the nasal and paranasal mucosa with numerous emigrated leukocytes. L-Selectin on leukocytes and its endothelial glycosylated ligands initiate leukocyte infiltration into inflamed tissues. Endoscopic sinus surgery (ESS) is the major approach for restoring sinus physiology after failure of conservative therapy; however, the effect of enlarging the maxillary sinus ostium is still unknown. Here, we compared two histological markers of local inflammation, the number of mucosal eosinophils, and the expression of endothelial L-selectin ligands, with clinical outcomes after enlarging or saving the maxillary sinus ostium.

METHODS

Twenty-three patients with CRS underwent uncinectomy on one side and additional middle meatal antrostomy on the other side. Maxillary sinus mucosa biopsy specimens from these patients and nine healthy subjects were taken for immunohistochemical evaluations of the number of mucosal eosinophils and endothelial L-Selectin ligands. Also, symptoms and mucociliary clearance were measured.

RESULTS

The postoperative reduction of the endothelial L-Selectin ligands was independent of the operation technique. There was a correlation between postoperative number of mucosal eosinophils and symptom score, which was also independent of the surgical technique. The postoperative decrease of mucosal eosinophils, as well as the correlation of the intraoperative eosinophils with the postoperative symptom score, was found only on antrostomy side.

CONCLUSION

ESS decreases the expression of endothelial L-Selectin ligands, which might lead to decreased eosinophil traffic into maxillary sinus mucosa, putatively more when enlarging the maxillary sinus ostium. Both intra- and postoperative low number of eosinophils seem to be indicators of good subjective recovery.

Local IgE and inflammation in chronic rhinosinusitis of asthmatics and non-asthmatics

The aim of the study was to show the difference in the pattern of inflammation, and Th1/Th2 polarization between asthmatic and non-asthmatic patients with CRS, specifically eosinophil activation, local IgE levels in the sinus fluid and tissue, and the severity of inflammation were measured. The maxillary sinus lavages, mucosal biopsies and bacteriological swabs were taken in 17 asthmatic and 36 non-asthmatic adult patients with CRS. The concentrations of IgE, eosinophil cationic protein (ECP), myeloperoxidase (MPO), and tryptase were analyzed and IgE+ cells, eosinophils, lymphocytes and plasma cells were counted. The granulocyte activation markers and IgE in sinus lavages, and the inflammatory and IgE+ cells counts were significantly higher in the asthmatics with the greatest difference in ECP and IgE concentrations. The tryptase concentrations did not differ, but only in the asthmatics they correlated significantly with the IgE concentrations and IgE+ cells count. Asthmatic patients present a distinct subgroup among the patients with chronic rhinosinusitis (CRS). The levels of the cellular markers and IgE in the sinus fluid differ from those of non-asthmatic patients with CRS. The activation of granulocytes (especially eosinophils), local IgE concentrations and the inflammatory cells infiltration are significantly higher in the asthmatics.

Effect of desloratadine on epithelial cell granulocyte-macrophage colony-stimulating factor secretion and eosinophil survival

BACKGROUND

Second-generation antihistamines are H(1) receptor antagonists and may have additional anti-inflammatory effects.

OBJECTIVE

The aims of the study were to evaluate the effect of desloratadine (DL) on cytokine secretion by epithelial cells from both nasal mucosa (NM) and polyps (NP), and on eosinophil survival primed by epithelial cell secretions.

METHODS

Epithelial cells were cultured and stimulated with fetal bovine serum (FBS), IL-1beta or TNF-alpha with and without DL for 24 h. Culture supernatant cytokines concentration were measured by ELISA. Peripheral blood eosinophils were incubated with human epithelial cell conditioned media (HECM) and DL. Eosinophil survival was assessed by Trypan blue dye exclusion. Results are expressed as mean+/-SEM of cytokine concentration (pg/mL) or eosinophil survival index (%).

RESULTS

FBS increased granulocyte-macrophage colony-stimulating factor (GM-CSF), vascular endothelial growth factor (VEGF), IL-6, IL-8, and TGF-beta(1) secretion in epithelial cell cultures from both NM and NP. Only GM-CSF secretion was significantly (P<0.05) inhibited by a dose-response of DL compared with positive controls, in both NM (10(-5) m: 125+/-36 pg/mL, 10(-6) m: 95+/-22 pg/mL vs. control: 256+/-91 pg/mL, n=6) and NP (10(-5) m: 80+/-29 pg/mL, 10(-6) m: 109+/-45 pg/mL vs. control: 333+/-212 pg/mL, n=6). DL also showed an inhibitory effect on HECM-induced eosinophil survival from both NM and NP. At 72 h, DL significantly (P<0.01) inhibited eosinophil survival induced by HECM from NM (10(-5) m: 19.9+/-5.5%, n=9; 10(-6) m: 28.7+/-7.7%, n=9) and NP (10(-5) m: 6.2+/-2.8%, n=11) compared with HECM alone (NM: 42.1+/-7.3%; NP: 45.3+/-8.1%).

CONCLUSION

The inhibitory effects of DL on epithelial cell GM-CSF secretion and on eosinophil survival induced by epithelial cell secretions, suggest that this H(1) antagonist may regulate eosinophil inflammation in upper airways.

Endothelial L-selectin ligands in sinus mucosa during chronic maxillary rhinosinusitis

RATIONALE

Chronic rhinosinusitis is characterized by persistent inflammation of the nasal and paranasal mucosa with numerous emigrated leukocytes. L-selectin on leukocytes and its endothelial glycosylated ligands initiate organ-specific leukocyte infiltration into inflamed tissues.

OBJECTIVES

The purpose of this study was to evaluate the endothelial expression of functionally active endothelial L-selectin ligands, sulfated sialyl Lewis x, in maxillary sinus mucosa from patients with chronic rhinosinusitis and from normal control subjects.

METHODS

Maxillary sinus mucosa specimens (116) were obtained surgically and immunohistochemically stained with monoclonal antibodies detecting sialyl Lewis x or sulfated extended core 1 lactosamines. The severity of the inflammation was determined by intraoperative endoscopic findings, computed tomography scans, and histopathologic assessment of the specimens.

MEASUREMENTS AND MAIN RESULTS

The percentage of vessels expressing endothelial sulfated sialyl Lewis x epitopes increased during chronic rhinosinusitis compared with uninflamed control tissue, especially in patients with additional allergic rhinitis, and decreased in specimens from aspirin-intolerant patients with preoperative oral corticosteroid treatment. In addition, the expression level of endothelial sulfated sialyl Lewis x epitopes and the number of mucosal eosinophils correlated with the severity of the inflammation, and decreased in specimens taken 9 months postoperatively compared with intraoperative samples, especially in patients with intranasal corticosteroid treatment.

CONCLUSIONS

Our results suggest that functionally active L-selectin ligands might guide leukocyte traffic into maxillary sinus mucosa preferentially in patients with severe findings of chronic maxillary rhinosinusitis, thus leading to aggravation of the inflammation.

Mast cells and tryptase in the middle ear of children with otitis media with effusion

OBJECTIVES

This is the first report of the presence of tryptase, a reflection of mast cell activity, in chronic middle ear effusion of patients in whom atopic status was characterized.

DESIGN AND METHODS

Mediator activity of mast cells and eosinophils was measured prospectively from effusion of 33 random patients and five controls with chronic otitis media with effusion (OME). Atopy was determined by enzyme-linked immunosorbent assay testing. Middle ear biopsies from a second group of eight OME patients and four controls were fixed in plastic and stained immunohistochemically for mast cells.

RESULTS

Sixty-one percent of patients had extensive activation of mast cells in their middle ears. Among those with elevated tryptase in their effusion, 95.6% were atopic and 94.7% also had elevated effusion eosinophilic cationic protein. Tryptase was elevated only in the effusion of atopic patients as compared with controls (P < 0.01). Mast cells were present in six of eight OME ears and absent in all four normals.

CONCLUSION

Mast cells and its mediator tryptase, both indicators of a Th2-driven immune response, are present in the majority of ears which have chronic effusion, suggesting that the inflammation within the middle ear of most OME patients is allergic in nature.

Evidence of mast cell activity in the middle ears of children with otitis media with effusion

OBJECTIVES

This is the first study to report the presence of tryptase, a reflection of mast cell activity, in chronic middle ear effusion of patients whose atopic status was characterized.

DESIGN AND METHODS

Mediator activity of mast cells and eosinophils was measured prospectively from effusion of 33 randomly selected patients and 5 control subjects with chronic otitis media with effusion (OME). Atopy was determined by enzyme-linked immunosorbent assay. Middle ear biopsies from a second group of 8 OME patients and 4 controls were fixed in plastic and stained immunohistochemically for mast cells.

RESULTS

Sixty-one percent of patients had extensive activation of mast cells in their middle ears. Among those with elevated tryptase in their effusion, 95.6% were atopic and 94.7% also had elevated levels of effusion eosinophilic cationic protein (ECP). Tryptase levels were elevated only in the effusion of atopic patients, as compared with 5 controls (P < .01). Mast cells were present in 6 of 8 OME ears and absent in all 4 normal ears.

CONCLUSION

Mast cells and its mediator tryptase, both indicators of a Th2-driven immune response, are present in a majority of ears that have chronic effusion. These findings support the hypothesis that middle ear mucosa is capable of an allergic response and that the inflammation within the middle ear of most OME patients is allergic in nature.