Antibodies to dietary antigen in serum from patients with sickle cell anemia.

The levels of antibodies of the IgG, IgA and IgM isotypes reacting against ovoalbumin (OVA), gliadin (GL) and cow's milk proteins (CMP), were determined by ELISA in sera from a group of adult patients with sickle cell anemia (SCA) bearing homozygous Ss hemoglobinopathy and from matched health donors. Only patients with steady-state disease were included in the study. Increased amounts of IgG and IgA reacting with OVA, GL and CMP were observed in the group of patients as compared with the controls. In contrast, the levels of IgM antibodies against each of the three dietary antigens were similar in patients and controls. Increased levels of IgG and IgA antibodies against dietary antigens in SCA may result from enhanced permeability of the gut mucosa to macromolecules of dietary origin as a consequence of microinfarctions, chronic polyclonal B cell activation and/or diminished inhibitory control of antibody synthesis.