title: [Antibody-deficiency syndrome].
abstract: Antibody deficiency syndromes (ADS) are defined by the inability of the organism to maintain sufficient concentrations of specific antibodies in circulation. The carriers of antibodies, the immunoglobulins, are a well-defined class of plasma proteins. Some of the pertinent knowledge on their structure and function is briefly summarized. Clinical classification of ADS may be based on different criteria: etiological and pathogenetic views are here used according to needs. Primary ADS are the result of deficient synthesis, and secondary ADS are due to increased catabolism and/or loss of antibodies. Etiological factors in primary ADS are congenital disturbances (hereditary deficiency, e.g. agammaglobulinemia), regulatory imbalances (e.g. infantile hypogammaglobulinemia) or acquired disease (e.g. malignant monoclonal lymphoma). Among the causes of acquired ADS as one example diseases leading to protein loss, are discussed. However, the whole problem may not be summarized so briefly, and this is exemplified in two illustrative examples of genetically determined diseases (hereditary deficiency of transcobalamin II and of adenosine deaminase). Patients with congenital metabolic deficiences may be considered as "experiments of nature". Their extensive study has essentially contributed to new knowledge and insights into normal physiological mechanisms. This is also true in immunology where the discovery of fundamental facts is connected with such studies.
mesh_terms: D000293:Adolescent; D000361:Agammaglobulinemia / Q000150:complications; D000917:Antibody Formation; D001402:B-Lymphocytes / Q000276:immunology; D001666:Binding Sites, Antibody; D002648:Child; D002675:Child, Preschool; D006801:Humans; D007136:Immunoglobulins / Q000302:isolation & purification; D007153:Immunologic Deficiency Syndromes / Q000209:etiology / Q000276:immunology*; D007223:Infant; D007231:Infant, Newborn; D008223:Lymphoma / Q000150:complications; D008297:Male
chemical_list: D007136:Immunoglobulins
vernacular_title: Das Antikörpermangel-Syndrom.