Influence of tonsillar disease on the expression of J chain by immunoglobulin-producing cells in human palatine and nasopharyngeal tonsils.

A significant reduction of the percentage of J-chain-positive intra- and extra-follicular IgA immunocytes was found in inflamed palatine tonsils. There was a tendency to similar alterations in hypertrophied adenoids. Tonsillar disease apparently enhances local maturation of the B-cell system, perhaps on the basis of intensified proliferation of memory clones. Alternatively, there may be a disease-associated defect in the mechanism(s) that normally induced switchover to the IgA isotype early in clonal development. It is speculated that, by decreasing the J-chain expression during local B-cell differentiation, tonsillar disease may jeopardize the potential of the tonsils as a putative precursor source for the secretory immune system of the upper aero-digestive tract.