Étude de la fonctionnalité des sous classes d'IgG

Children who have recurrent infections require laboratory investigation for eventual immunodeficiency. We measured specific IgG antibodies against tetanus toxoid, diphteria toxoid, pneumococcal capsular polysaccharide and Haemophilus influenzae b in serum of 70 children without pulmonary symptoms. We compared to the study of humoral immune function in 128 children with obstructive bronchopneumopathies.We observed that functional antibody deficiency may be present despite normal IgG subclass levels and conversely deficiency levels of a single subclass of IgG may be found in individuals who have effective specific antibody production and are clinically normal. Measurement of specific antibody response to bacterial antigens and the identification of children with selective antibody deficiency are important for diagnostic and therapeutic management.