MUCOPOLYSSACCHARIDOSES TYPE IV: CASE OF A PATIENT WITH HUMORAL RESPONSE DEFICIENCY

Abstract

The mucopolysaccharidoses (MPSs) are a group of rare diseases characterized by deficiencies in different enzymes required for degradation of complex carbohydrates. The enzymatic deficiencies lead to abnormal accumulation of deposits of glycosaminoglycans. Once the lysosome is important for normal functioning of the immune system, playing a key role in the expression of cellular membrane receptors, the presentation of antigens, the secretion of cytokines and phagocytosis. We presume that these processes may be impaired in patients with MPSs. The presence of recurrent respiratory infections in these individuals may be a clinical clue of the immune dysregulation in MPSs. Humoral immunity refers to antibody production by B cells. Antibodies play role of pathogen and toxin neutralization, classical complement activation, and opsonin promotion of phagocytosis and pathogen elimination. We evaluated the humoral and cellular immunity of a male patient with 20 years old with MPSs type IV. We performed the measurement of total serum antibodies IgG, IgM, IgA and IgE and immunophenotyping of B and T cells. The patient present low levels of total IgM and IgA antibodies with normal levels of total IgG and IgE antibodies. B cell and B- memory deficiency was observed. Relative values of TCD4+ and TCD8+ cells were normal in this patient. We report here that this patient have a defect of humoral immunity with B cells deficiency and low levels of IgM and IgA serum antibodies. This is the first report at literature of a MPSs type IV patient with humoral immunodeficiency.