Masaki Ohnishi

Changes in nasal metachromatic cells during allergen immunotherapy

We have investigated changes of nasal metachromatic cell number, nasal symptoms and nasal provocation at the third and sixth month during allergen immunotherapy. Twenty‐five subjects with perennial allergic rhinitis (house dust (23), Alternaria (2)) were divided into two groups: an immunotherapy‐treated group (n= 14) and a control group (n=11). At the first visit nasal symptom scores, nasal provocation reactions and the number of metachromatic cells in nasal mucosal epithelial scrapings were not significantly different between groups. At the third and sixth month after immunotherapy nasal symptom scores, nasal provocation and the metachromatic cells in epithelial scrapings were significantly reduced (P < 0.05) compared with the pretreatment values in the immunotherapy group, but unchanged in the control group. These results suggest that the reduction in metachromatic cell number at the nasal mucosal surface may be one of the mechanisms which could explain the improvement of nasal allergic symptoms by immunotherapy.

Mast cell quantitation in nasal polyps, sinus mucosa and nasal turbinate mucosa

The distribution and abundance of mast cells in nasal polyps, the maxillary sinus mucosa of patients with sinusitis and the turbinate mucosa of allergic rhinitis was microscopically examined using different methods of fixation. In the epithelium of the surface and the ducts of nasal polyps (n = 8), the mean number of mast cells was over 20,000 per mm3 using Motas fixation and the increase was correlated with the epithelial thickness (P < 0.05). On the other hand those of the maxillary sinus mucosa (n = 6) and the nasal turbinate mucosa (n = 7) were less than 6,000 per mm3. In the subepithelial layer or areas deeper than the area with the glands, however, mast cell counts were less than 3,200 per mm3 in all diseases. More than 70-90 per cent of all mast cells in the epithelium of the mucosal surface and the ducts of the polyp, the maxillary sinus mucosa and nasal turbinates were formalin sensitive. Most of the mast cells in the subepithelial and deeper areas were formalin resistant in all diseases. These results suggest that conditions for mast cell growth differ between polyps and the other diseases, and that the conditions which affect mast cells may contribute to polyp development.

Specific IgA and IgG antibodies to house dust mite Dermatophagoides farinae in nasal secretions

As far as we know, IgA and IgG antibodies to purified house dust mite allergens Der fI and Der fII in nasal secretions have never been documented. Therefore, we determined specific IgA, SIgA and IgG antibodies (abs) to crude extract of D. farinae and its purified allergens Der fI and der f II in nasal secretions collected by aspiration from 34 normal subjects, 25 untreated nasal allergic patients and 28 treated nasal allergic patients on parenteral immunotherapy by means of an avidin-biotin ELISA. The following results were obtained. (1) The specific IgA, SIgA and IgG abs to each of the three kinds of allergens correlated with each other. The groups of patients with nasal allergy (both treated and untreated) showed higher levels of specific IgA, SIgA and IgG abs to the allergens than the normal group. (2) In the group of treated patients, the levels of specific abs were not correlated with the clinical improvement of symptoms or the degree of response to nasal challenge. (3) The treated patients failed to show significantly higher levels of abs in nasal secretions than the untreated patients. (4) The specific IgA and SIgA abs in nasal secretions seemed to be predominantly produced locally, and IgG abs might be transudated from the circulation.

Distribution of Mast Cells in Inverted Papilloma and Squamous Cell Carcinoma of the Nose

An increased number of mast cells is found in the epithelial layer of the nasal mucosa of allergic subjects. However, the mechanism of accumulation of the intraepithelial mast cells has not yet been clarified. We have previously shown that the increase of intraepithelial mast cells is related to the proliferation of nasal epithelial cells in vivo, and inverted papilloma and squamous cell carcinoma of the nose seem to be in vivo proliferative states of nasal epithelium. To clarify the mechanism of the accumulation of intraepithelial mast cells, we studied the relationship between nasal tumors of epithelial cell origin and the accumulation of mast cells. Accumulation of mast cells was observed in the nasal inverted papilloma, especially within 50μm from the basement membrane at the tumor site, which might be the site of maximum proliferation of tumor cells as well as secretion of cytokines. The majority of mast cells accumulated were formalin sensitive mast cells (mainly MMCs). On the other hand, in the squamous cell carcinoma of the maxillary sinus, fewer mast cells were found. Results of this study suggest that the accumulation of intraepithelial mast cells is associated with the proliferation of nasal epithelial cells.

Basophil degranulation test for nasal allergy.

Allergolam is a new kit (Institute Pasteur Production, Paris) for human basophil degranulation testing (HBDT) and is used to diagnose reaginic allergy.To test the reliability of this kit, we compared the results of HBDT with those of skin tests, RAST and nasal provocation tests in 49 patients. To test its reproducibility, we performed the HBDT four times in one patient, and twice in three patients. To test the specificity of this test to allergens, five patients allergic to Japanese cedar, were tested for house dust allergen (HD).We found a significant correlation between the results of the HD HBDT and HD provocation test and HD RAST. We also found a significant correlation between the results of mite HBDT and mite skin test or mite RAST. There was, however, no significant correlation between the results of HD HBDT and HD skin tests. In regard to the specificity to allergens, HBDT for HD allergen was negative in five patients with Japanese cedar allergy. The test results were not markedly different in two or four repetitions.The above results indicate that HBDT is highly reproducible, specific to allergen and useful in the diagnosis of reaginic allergy. In a comparison of HBDT with RAST, HBDT required a minimum equipment, was easier to perform and almost as reliable as RAST.