Specific IgA against multiple antigens as expression of immunologic deregulationin HIV-positive children

B-cell dysfunction in HIV-infected children is reflected by hypergammaglobulinemia and high levels of serum IgA. Little is known about antibody specificity since only a small portion of serum IgA appears to be directed against HIV proteins. In the present study the specificity of IgA antibodies against food, inhalant, bacterial and fungi antigens were evaluated in a population of HIV infected children. ELISA method was used for antibody testing. Our results show that in 84.6% of patients IgA against at least one food antigen are present. IgA against inhalant allergens were present in most of HIV-infected children but in none of controls. As for anti-tetanus toxoid antigens and anti-fungi antigens, though present in higher percentage in patients, specific IgA were found also in healthy children. If a gastrointestinal dysfunction might be supposed as the cause of presence of anti-food antigen IgA, it is difficult to consider this factor as the cause of presence of specific IgA directed against different antigens. It is possible to postulate that an immunologic dysregulation based on an imbalance between Th1 and Th2 cells or on higher levels of IL-5 and/or IL-6 may lead to a misfunction of B cell and consequently to hypergammaglobulinemia with high IgA levels.