PMBL have shown to exert atherapeutic and preventing effect in acute and recurrent infections of the upperairways, which is significantly correlated with the activation and enhancement ofboth IgM memory B lymphocytes (CD24+/CD27+cells) and IL-2 receptor-expressing lymphocytes(CD25+ cells) involved either in humoral or cellularimmunity. The gene discussed is IL2RA; the disease is infection.