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Background IgG to galactose-α-1,3-galactose (α-gal) are highly abundant natural antibodies (Ab) in humans. α-Gal-specific IgE Ab cause a special form of meat allergy characterized by severe systemic reactions 3-7 h after consumption of red meat. We investigated 20 patients who experienced such reactions and characterized their α-gal-specific IgE and IgG responses in more detail. Methods α-Gal-specific IgE was determined by Immuno CAP. IgE reactivity to meat extract and bovine gamma globulin ( BGG) was assessed by immunoblotting and ELISA, respectively. In some experiments, sera were pre-incubated with α-gal or protein G to deplete IgG Ab. α-Gal-specific IgG1-4 Ab in individuals with and without meat allergy were assessed by ELISA. Results In immunoblots, BGG was the most frequently recognized meat protein. Binding of IgE and IgG to BGG was confirmed by ELISA and completely abolished after pre-incubation with α-gal. Neither the depletion of autologous α-gal-specific IgG Ab nor the addition of α-gal-specific IgG Ab from nonallergic individuals changed the IgE recognition of BGG of meat-allergic patients. Meat-allergic patients showed significantly higher α-gal-specific IgG1 and IgG3 Ab than nonallergic individuals, whereas the latter showed significantly higher levels of α-gal-specific IgG4 Ab. Conclusion Patients with delayed meat allergy display IgE and IgG Ab that selectively recognize the α-gal epitope on BGG. Their enhanced α-gal-specific IgE levels are accompanied by high levels of α-gal-specific IgG1 devoid of IgE-blocking activity. This subclass distribution is atypical for food allergies and distinct from natural α-gal IgG responses in nonallergic individuals. [ABSTRACT FROM AUTHOR]

In 15 infants between 1 and 31 weeks the effect of antidiuretic hormone (ADH) on the renal concentrating capacity and urinary cyclic AMP (cAMP) was tested. A significant decrease of urine flow and a significant increase of osmolality, urea and cAMP was observed indicating that the distal nephron of the infant kidney is responsive to exogenous ADH and that its effect is mediated by cAMP. The results of a second series with 52 normally hydrated infants demonstrate that the nonlinear age-related increase of osmolality and urea in urine is accompanied by a similar pattern of cAMP excretion, pointing out that the maturation of the concentrating capacity seems to be related to an increasing responsiveness of the cAMP system to ADH. Furthermore the results raise the possibility that increasing concentrations of urea and solutes in the medulla and papilla of the infant kidney may have-in the presence of very low ADH secretion-an additional stimulating effect on cAMP formation. [ABSTRACT FROM AUTHOR]

IgM, IgG, and IgG antibodies to Eimeria bovis first-generation merozoite antigens were determined by enzyme-linked immunosorbent assay and Western blotting in naturally infected cows and in their offspring before and after the uptake of colostrum. In addition, calves were examined following experimental primary and challenge infections. Neonate calves received maternal antibodies via colostrum. All isotypes determined were transmitted, but only IgG was concentrated in the colostrum and it occurred at significantly increased levels in sera from the calves as compared with those from the respective dams. Recognition patterns (Western blotting) displayed by related maternal serum and colostrum and those shown by calves that had ingested colostrum were very similar, but marked variations occurred between individual pairs. Experimental infection of 15-week-old calves with 0.7×10 oocysts caused strong protective immunity against a challenge with 1×10 oocysts. In contrast, animals that had undergone a weak intercurrent infection were not protected. Experimental infections induced a considerable increase in IgG and IgG antibody levels, whereas IgM values increased only slightly. The spectrum of merozoite antigens recognized by the sera increased markedly after experimental infection, although high individual variations were found in the calves. However, there was no correlation between the levels of any specific antibody or the recognition patterns and the status of immunity to a severe challenge. [ABSTRACT FROM AUTHOR]