The Production of Antisera to Human γG Subclasses in Rabbits Using Immunological Unresponsiveness

Abstract

Abstract It has been demonstrated that human γG immunoglobulins (γG) can be divided into four subclasses on the basis of antigenic differences in the heavy chain (1, 2). The antigenic differences between the subclasses are not pronounced and it is therefore difficult to obtain subclass-specific antisera. In the past, antisera usually have been produced in primates, because primates form more antibodies toward subclass-specific determinants than do rodents. However, even in primates, most of the antibodies that are produced react with γG of all subclasses and only after prolonged immunization and appropriate absorption can subclass-specific antisera be obtained. In addition, primates are not easily maintained in laboratories and not all of them form subclass-specific antibodies. For these reasons experiments were undertaken to develop a method to produce human γG subclass-specific antisera in rabbits. Since it has recently been shown that under certain conditions rabbits can form antibodies to one portion of the γG molecule while remaining unresponsive to another (3), rabbits were rendered tolerant to one γG subclass and immunized with γG of another subclass.