Changes in nasal metachromatic cells during allergen immunotherapy

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.

Epitope-specific T cell tolerance to phospholipase A2 in bee venom immunotherapy and recovery by IL-2 and IL-15 in vitro.

“…Induction and rise in IgG antibodies, particularly of the IgG4 class (1-3), or the generation of CD8 ϩ cells which may modulate allergen-specific IgE production, have been claimed to be responsible for successful immunotherapy (4). Other observations demonstrated reduced numbers of mast cells and secretion of mediators (5,6). Similarly, numbers and activation of eosinophils were reduced in inflamed tissue upon immunotherapy (7,8).…”

Influence of grass pollen immunotherapy on cellular infiltration and cytokine mRNA expression during allergen-induced late-phase cutaneous responses.

“…Other proposed mechanisms for immunotherapy include reduction in serum concentrations of neutrophil chemotactic activity (32), reduced local numbers of eosinophils (33) and eosinophil cationic protein (34), and a reduction in the numbers of mast cells in the nasal mucosa (35). Immunotherapy has also been shown to suppress allergen-induced T cell proliferative responses (36) and to induce an increase in circulating numbers of allergen-specific CD8+ lymphocytes (37).…”

Role of interleukin 10 in specific immunotherapy.

“…Stimulation of IgG4 antibodies and a decline of the IgE/IgG4 anti-PLA antibody ratio (15)(16)(17)(18)(19)(20) were claimed to be responsible for successful SIT. Also, the generation of IgE downregulating CD8 ϩ T cells and reduced numbers of mediator-secreting mast cells and eosinophils (21)(22)(23)(24)(25) were found in SIT. Moreover, successful SIT of allergic rhinitis was shown to be associated with decreased numbers of Th2 and increased IFN-␥ -producing cells (26).…”