CD4 and gonorrhea: It is possible that after encountering with the antigen, allergen-specific CD4+ T cells from PAC patients would be able to secrete IL-6, as it was observed after in vitro stimulation, interfering with CD4+CD25+FOXP3+ differentiation, since it has been described that Treg cell differentiation requires antigen stimulation by engagement T cell receptor to induce FOXP3 expression [21].