T-CELL SUBSETS IN ADENOIDS AND PERIPHERAL-BLOOD RELATED TO AGE, OTITIS-MEDIA WITH EFFUSION AND ALLERGY

Adenoids and peripheral blood samples from 29 children (20-120 months of age) undergoing adenoidectomy for long-standing otitis media with e ffusion (OME) (n=16) or obstructive adenoid hyperplasia (n=13) were in vestigated by flow cytometry for their T-lymphocyte profile. Eleven of the enrolled children were allergic to inhalant and/or food allergens . For the whole group, the percentage of helper T cells belonging to t he memory phenotype (CD4(+)/CD45RO(+) cells) was significantly higher in adenoids than in blood (p<0.0001), while the same cell category inc reased with age in peripheral blood (p<0.01). A highly significant neg ative regression (p<0.001) was found between age and the percentage ra tio of CD4(+) cells that were CD45RO(+) in adenoids and blood. Allergi c children had a higher CD4(+)/CD8(+) ratio for cells expressing CD45R O(+) (p<0.05) in adenoids. The results of this study indicate that ade noids participate in the development of an immunological memory. Our f indings support a relationship between allergy and memory cells in ade noids.