Immunocytochemical distribution of the c-H-ras protein in nasal polyps: localization to the terminal bars

Cellular comparison of sinus mucosa vs polyp tissue from a single sinus cavity in chronic rhinosinusitis

BACKGROUND

Nasal polyposis is a common development in chronic rhinosinusitis (CRS), and sinus mucosa and polyp tissue have been used interchangeably in studies investigating CRS. However, potential differences may exist between these 2 tissue types, which have not been entirely characterized.

METHODS

A cross-sectional study of CRS with nasal polyposis (CRSwNP) patients undergoing endoscopic sinus surgery was conducted. Sinus mucosal biopsies and corresponding polyp tissue were obtained from the same sinus cavity via flow cytometry, single-cell suspensions identified type 2 innate lymphoid cells (ILC2s), CD4 and CD8 T cells, activated CD4 and CD8 T cells, plasma cells, plasmacytoid dendritic cells (pDCs), regulatory T cells, T follicular helper cells, B cells, and immunoglobulin A (IgA)(+) and IgG(+) B cells. Cells were measured as a percentage of CD45(+) cells. Paired nonparametric comparisons between sinus and polyp tissue were performed.

RESULTS

Ten patients (50% female; age 48 ± 16 years) were recruited. Significantly elevated ILC2 levels were found in polyp tissue compared to sinus mucosa (0.12 [0.07 to 0.23] vs 0.07 [0.04 to 0.16], p = 0.02), as well as plasma cells (2.25 [0.84 to 3.68] vs 1.18 [0.74 to 2.41], p = 0.01); pDCs (0.15 [0.12 to 0.50[ vs 0.04 [0.02 to 0.17], p = 0.03); activated CD8 T cells (29.22 [17.60 to 41.43] vs 16.32 [10.07 to 36.16], p = 0.04) and IgG(+) B cells (6.96 [0.06 to 11.82] vs 1.51 [0.38 to 5.13], p = 0.04). Other cell populations showed no significant differences.

CONCLUSION

Polyps have a similar cellular composition to that of mucosa. Higher levels of ILC2s, plasma cells, pDCs, activated CD8 T cells, and IgG(+) B cells in polyp tissue may be reflective of cell populations driving nasal polyp development. The cellular machinery of CRS is present in polyps and representative of the disease process. This pilot study strongly suggests that a larger study would provide significant insights into the relationship of sinus mucosa to pathogenesis of nasal polyps.

Expression of epidermal growth factors and a tight junction protein in the nasal mucosa of patients with chronic hypertrophic rhinitis

BACKGROUND

ErbB family receptors and tight junction proteins participate in the pathologic process including tissue remodelling of inflammatory diseases in the upper and lower respiratory tracts. This study aimed at investigating the expressions of erbB1, 2, 3, 4, and a tight junction protein, claudin-1, in the nasal mucosa of patients with chronic hypertrophic rhinitis.

METHODS

Inferior turbinates were collected from 10 turbinectomised patients with allergic and non-allergic chronic hypertrophic rhinitis. The expressions of erbB1, 2, 3, 4, and claudin-1 were examined by fluorescence immunohistochemistry and by quantitative real-time transcription-polymerase chain reaction (qRT-PCR).

RESULTS

All erbB1-4 and claudin-1 were detected, and mainly localised in the epithelial cells and nasal gland cells. The immunoreactivity for claudin-1 was positively correlated with the expressions of erbB1, 2 and 4, but negatively correlated with that of erbB3. The mRNA expressions of erbB1, 2 and 4 were positively correlated with one another, whereas the expression of erbB3 showed negative correlation with the immunoreactivity for erbB2 and 4.

CONCLUSIONS

These results suggest a possible participation of erbBs and claudin-1 in tissue remodelling in chronic hypertrophic rhinitis.

Different expressions of erbB1/2 and tight junction proteins in hypertrophic inferior turbinates and nasal polyps

Both inferior turbinate hypertrophy and nasal polyp formation entail the enlargement of the nasal mucosa caused by rhinosinusitis, but their macro/microscopic and clinical findings differ markedly. This study aimed at investigating differences in the expressions of erbB1/2 and the tight junction proteins, claudin-1 and tricellulin, in the two tissues. Ten inferior turbinates and ten nasal polyps were collected. The expressions of erbB1/2, claudin-1, and tricellulin were examined by fluorescence immunohistochemistry and by quantitative real-time transcription-polymerase chain reaction (qRT-PCR). The eosinophil count and % of nasal gland area in the mucosa were also measured. The fluorescence intensities in the inferior turbinates were higher for erbB1/2 and lower for claudin-1 than those in the nasal polyps. The results of qRT-PCR were consistent with the immunohistochemical findings for erbB1/2. The quantity of tricellulin mRNA was significantly higher in the inferior turbinates than in the nasal polyps. The % of nasal gland area was significantly higher but the eosinophil count was significantly lower in the inferior turbinate than in the nasal polyp. These results suggest that the underlying pathogenesis of hypertrophic inferior turbinates and nasal polyps is likely to differ with respect to regeneration/proliferation and thus the remodeling process.

Expression of epidermal growth factors, erbBs, in the nasal mucosa of patients with chronic hypertrophic rhinitis

PURPOSE

To investigate the expression of erbBs in the nasal mucosa of patients with chronic hypertrophic rhinitis.

PROCEDURES

Inferior turbinates were collected from 12 turbinectomized patients with allergic and nonallergic chronic hypertrophic rhinitis. Differential cell counts in the peripheral blood and allergy tests were conducted before surgery. The expressions of erbB1, 2, 3 and 4 were examined by fluorescence immunohistochemistry and by quantitative real-time transcription polymerase chain reaction (qRT-PCR). Immunohistochemical fluorescence was quantitatively measured using image-analyzing software. Eosinophils infiltrated into the mucosa were counted in sections stained with Hansel solution.

RESULTS

Each of the erbB types 1-4 was expressed in both epithelial cells and nasal gland cells. Immunoreactivity for erbB1 was strong and that for erbB2 and 3 was moderate, while that for erbB4 was faint. These findings were consistent with the results of qRT-PCR. The percentage of peripheral blood eosinophils was significantly correlated with the eosinophil count in the nasal mucosa and with immunoreactivity for erbB1 in the nasal gland.

CONCLUSIONS

These results suggest a possible role of eosinophils in regulating erbB1 and thus in regulating mucosal hypertrophy in chronic hypertrophic rhinitis.