No abstract

We previously demonstrated that fluctuations in circulating metachromatic cell progenitors were inversely related to nasal metachromatic cell (NMC) counts and nasal symptoms in allergic rhinitis. Now, we have quantitated NMC progenitors and lineage-specific growth factors using a hemopoietic colony assay. Cell suspensions from excised collagenase-treated nasal polyps (n = 7) contained 3.8 +/- 1.1 granulocyte colony-forming cells per 10(6) cells plated, compared to less than or equal to 0.5 in human tonsil suspensions, less than or equal to 0.5 in nasal mucosal epithelial scrapings, and 33 +/- 8 in peripheral blood of patients with ragweed allergic rhinitis (p less than 0.01). The percentage of metachromatic cells in nasal-polyp-derived colonies was 47 +/- 10 compared with 3.0 +/- 0.7 in peripheral blood colonies (p less than 0.005). Highly potent metachromatic cell colony-stimulating activity (CSA) was detected in supernatants from cultured human nasal epithelial scrapings from both polyps and atopic nasal mucosa, but not from nonatopic nasal mucosa. Supernatants from polyp mononuclear cells stimulated with phytohemagglutinin also contained metachromatic cell-CSA, which had an approximate molecular size of 25 to 70,000 daltons on column chromatography. An IL-3-like activity was also detected in these supernatants. These observations provide further evidence for in situ hemopoietic mechanisms in human nasal mucosa, involving epithelium-derived stimulation of local metachromatic cell progenitor growth and differentiation in allergic rhinitis.

Delayed-type hypersensitivity with granulomatous lesions to silk sutures is rather rare. Yet, braided silk sutures often act as a non-immunologic foreign-body and cause a granulomatous inflammatory reaction years after surgery. We report here a case of recurrent granulomas with remarkable infiltration of eosinophils that may have resulted from an IgE-mediated hypersensitivity reaction to silk fibroin, a component of the braided silk suture. Under normal circumstances exposure to fibroin is rather rare. Therefore, the present patient may have developed this reaction to the silk sutures used in a previous surgery.

No abstract

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 less than 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.