What is an anti-idiotypic antibody?

With the development of drug research and development, there are more and more types of antibodies, such as camel antibodies, llama antibodies, monoclonal antibodies, recombinant antibodies, anti idiotype, anti-idiotypic antibodies and the like.

Definition of anti-idiotypic antibodies:

The first is a specific antibody induced by the idiotype of the variable region of the antibody as an antigenic epitope.

The second is specific antibodies that are unique to the unique type.

An anti-idiotypic antibody is an antibody directed against a specific epitope group (referred to as an idiotype) on the V region of an antibody molecule. The "intra-image" relationship with the determinant molecules of the original antigen can mimic the structure and function of the antigen, and can be used as a novel vaccine. It is an antibody that directly recognizes and binds to the variable region of another antibody. It plays a pivotal role in drug discovery, mainly for: immunogenicity analysis of antibody drugs, preclinical studies of therapeutic antibodies, clinical development of anti-drug antibodies, vaccine development, ligand neutralization assays and antibody blockade. The control of the test, the pharmacokinetic and pharmacodynamic analysis of the antibody drug, is used to detect the content of specific antibody drugs in the blood, including free form, combined form and total amount.

Preparation of anti-idiotypic antibodies:

There are two ways to prepare anti-idiotypic antibodies: traditional immune serum preparation and monoclonal antibody preparation. However, any anti-Id antibody prepared by any route must be absorbed by an agarose affinity chromatography column cross-linked with normal immunoglobulin (homologous to the antibody for immunization), and a purified idiotype antibody (ie, an immunological antibody). The cross-linked agarose affinity chromatography column absorbs and purifies, and finally, the purified anti-Id type antibody is fully identified. For the two preparation methods, they have their own characteristics, the polyclonal anti-Id antibody is simple to prepare, and the obtained intra-image anti-Id antibody (ie, the antibody against the idiotype determinant of the antibody binding site) is low in content; Monoclonal anti-Id antibodies are more versatile, but once an internal imaging anti-Id antibody is obtained, the yield is infinite.

Development of anti-idiotypic antibodies is a viable immunogen replacement technology

The idiotype of an antibody refers to a generic term for an idiotype-type antigenic determinant present on an antibody molecule that reflects the diversity of antibody molecules. An idiotype antibody (Ab1) refers to an antibody having a unique type of antigenic determinant, and an anti-idiotypic antibody (Ab2) is an antibody that produces a unique position on an antibody. The technology first appeared in 1974. Jeme proposed the famous immunological network theory based on Bumet's cell clonal selection theory. Based on Jeme's theory of immune network, Nisonoff and Lamoyl clearly pointed out that anti-idiotypic antibodies can substitute antigens to induce specific immune responses, which is a hotspot in biotechnology research in recent years.

Difficulties in the preparation of anti-idiotypic antibodies:

The variable region of the antibody is less immunogenic, resulting in a lower concentration and ratio of anti-idiotypic antibodies in the anti-serum, fewer positive clones and are easily lost. The solution is: coupling the protein carrier as an immunogen; selecting a suitable animal, optimizing the immunization program; and optimizing the clonal screening method.

Anti-idiotypic antibody application: anti-idiotype antibody vaccine

It is neither the natural antigen itself nor the artificial antigen itself, but the "simulation" of the antigen itself. When vaccinated with this vaccine, the animal can produce the corresponding pathogen although it is not directly exposed to the pathogenic microbial antigen. The immunity of microbial antigens is called an intrinsic antigen vaccine.

Since this vaccine uses an anti-Id antibody (Ab2) instead of an antigen as an immunogen, it is not possible to culture at this stage, and it is difficult to culture and has a low yield of pathogens; it is dangerous to prepare a vaccine directly from a pathogen, especially inversion. It is more meaningful to make a vaccine; a vaccine with a low immunogenicity and a polysaccharide antigen that cannot be produced by recombinant DNA technology.

Anti-idiotypic antibody vaccines may also be referred to as endoscopic vaccines. In recent years, it has been found that Ab2 is heterogeneous in functional properties, and is divided into four types: Ab2α, Ab2β, Ab2γ and Ab2δ. Among them, Ab2β corresponds to the binding position of Ab1, and the conformational antigen can be simulated in the conformation. The internal image of the antigen can be used as an anti-idiotype antibody vaccine, and other types belong to the non-antigen binding site on the recognition of Ab1, and cannot be used for preparing an anti-idiotype antibody vaccine. The unique type is generally monoclonal and is called a proprietary one. Some unique types can exist between allogeneic or heterogeneous individuals and are public or cross-reactive. The latter has practical significance in the preparation of unique vaccines.

The anti-idiotype antibody vaccine is a new type of immunobiological preparation developed in the late 1970s. Now it is developing in the practical field, such as using it to make vaccines and treat tumors, all of which have achieved certain effects. The vaccine is based on an antibody against a pathogenic microorganism as an antigen to immunize an animal. The unique determinant of the antibody can stimulate the body to produce an anti-idiotypic antibody, and the anti-idiotypic antibody is an internal image of the initiating antigen, which can stimulate the body to generate a pair of motions. The immune response of the antigen, thereby producing a protective effect.