Isoelectric spectra of different classes of anti‐erythrocyte antibodies

A method is described for visualizing isoelectric spectra of antibody against foreign erythrocytes. Different classes of immunoglobulins may be examined separately. After electrofocusing, anti‐SRBC bands are detected by overlaying the gel with molten agarose containing SRBC and anti‐globulin sera for different antibody classes. On addition of complement, bands of specific lysis appear, which are recorded photographically. Samples of sera from mice immunized with SRBC were electrofocused and bands of direct lysis and of γG2 — γG2a — developed lysis are shown. As the antigen dose is increased, more bands of γG2a anti‐SRBC antibody are detectable. The increase in the numbers of bands over the dose range used approximates to the increase seen in PFC over the same dose range. This method is quick and easy to perform and can also be used to detect antibody spectra against proteins, haptens and other antigens which can be linked to indicator red blood cells.