Moraxella catarrhalis-dependent tonsillar B cell activation does not lead to apoptosis but to vigorous proliferation resulting in nonspecific IgM production.
The respiratory pathogen Moraxella catarrhalis has a high affinity for human IgD and is mitogenic for peripheral blood B lymphocytes. Moraxella IgD-binding protein, which is a multifunctional outer membrane protein with adhesive properties, is responsible for the interaction. Previous experiments with the Ig-binding B cell superantigens protein A and protein L from Staphylococcus aureus and Peptos