Concentrations of antibodies against ß-amyloid 40/42 monomer and oligomers in Chinese intravenous immunoglobulins.

ABSTRACT

Intravenous immunoglobulin (IVIg) preparations are being investigated as a potential agent for treatment or prevention of Alzheimer's disease (AD). Antibodies towards soluble ß-amyloid (Aß) contained in IVIg were considered to be the major component contributing to the beneficial effect of the preparations in pilot studies. This study compared the antibody concentrations against Aß in Octagam® IVIg (Octapharma) and 9 IVIg preparations from different Chinese manufacturers by ELISA, using Aß40 monomer, Aß40 soluble oligomers, Aß42 monomer and Aß42 soluble oligomers as the antigens. The results showed that each preparation contained different antibody levels against the four Aß forms. The median values of the four antibody concentrations in Chinese IVIg preparations were 16.53, 8.47, 24.36 and 33.25µg/mL, which were remarkably higher than that in Octagam® IVIg (1.66, 2.07, 4.61 and 4.64µg/mL). Moreover, the anti-Aß42 oligomer antibody levels in almost all IVIg preparations were higher than the anti-Aß42 monomer antibody, and the concentrations of anti-Aß42 antibodies in most of the IVIg preparations were significantly higher than that of anti-Aß40 antibodies. These findings will contribute to an increased understanding of the uniqueness of Chinese IVIg preparations, and could provide support for a trial of a Chinese IVIg product in AD patients.