“…IvIg's benefits in these trials have been suggested to be due to antibodies to amyloid-beta (A), the major protein in plaques in the AD brain (Relkin et al, 2009), but other explanations, such as IvIg's anti-inflammatory and anti-complementary actions (Kazatchkine and Kaveri, 2001;Arumugam et al, 2007;Nimmerjahn and Ravetch, 2008), are also possible. The indirect enzyme-linked immunosorbent assay (ELISA) has been used to measure anti-A antibody concentrations in IvIg (Dodel et al, 2002;Relkin et al, 2007;Szabo et al, 2008) and in AD serum and plasma samples (Hyman et al, 2001;Nath et al, 2003;Baril et al, 2004;Moir et al, 2005;Jianping et al, 2006;Song et al, 2007;Gruden et al, 2004;Gustaw et al, 2008). The latter investigations produced conflicting results as to whether the levels of these antibodies are increased, decreased, or unchanged in 0165-0270/$ -see front matter © 2010 Elsevier B.V. All rights reserved.…”