The Four Subclasses of IgG Can Be Isolated from Mouse Serum by using Protein A‐Sepharose

Abstract

We confirmed the findings of Ey and colleagues that mouse IgG is absorbed by protein A-Sepharose at pH 8.0. Also confirmed was their finding that IgG1 mainly elutes from such a column by means of a buffer with pH 6.0 and that the corresponding pH values for IgG2a and IgG2b were 4.5 and 3.5. We made the new finding that the bulk of IgG2a bearing allotypes a or j eluted already at pH 5, in contrast to IgG2a bearing allotype b. Another new finding was that IgG3 was mainly eluted at pH 4.5 regardless of the allotype. All four subclasses of IgG could thus be physically separated if the allotype was a or j (the only known exception is allotype b). Separation of IgG2a and IgG3 was achieved even when the allotype was b by using a pH gradient for elution. IgG2a came out at a slightly higher pH than IgG3. Mouse IgG antibodies against group A streptococcal polysaccharide belonged mostly to IgG3 and, to a lesser extent, to IgG2a and IgG2b.

The Immunoglobulin G Subclass Responses of Mice to Influenza A Virus: the Effect of Mouse Strain, and the Neutralizing Abilities of Individual Protein A-purified Subclass Antibodies

“…Serum obtained from CBA, BALB/c and C57BL/6 mice 7 weeks after the secondary i.m. inoculation with purified H3 was fractionated on a Protein A-Sepharose 4B (Pharmacia) column according to the method of Seppala et al (1981). Protein A-Sepharose 4B was swollen in 10 mM-PBS pH 8, containing 0.1 ~ (w/v) sodium azide and packed into a glass column (Bio-Rad).…”

“…The IgG subclass antibodies were purified from the serum of CBA/CaH, BALB/c and C57BL/6 mice by the method of Seppala et al (1981). Mice were inoculated with purified H3 by the i.m.…”

Internalization and processing of antibodies to surface antigens on human B cells. Monoclonal anti‐IgM antibodies are processed differently than monoclonal antibodies towards non‐Ig surface receptors

“…It has previously been established that AB3 is an anti-HLA-DR antibody (MaDr) [18]. E01 was found to be specific for the common leukocyte [21]. Biotin-conjugated antibodies were prepared as described elsewhere [22].…”

Production and Immunological Characterization of a Monoclonal Antibody to Trichophyton quinckeanum: Interaction with Phosphorylcholine-bearing Components

“…aureus, reported to interact mainly with IgG class immunoglobulins (Lindmark et al, 1983). However, some IgM polyclonal antibodies (Seppala et al, 1981) and IgM monoclonal antibodies (R. M. Maizel, personal communication) bind protein-A.…”