Somatic generation of antibody diversity

Somatic generation of antibody diversity

Somatic generation of antibody diversity. Tonegawa S. In the genome of a germ-line cell, the genetic information for an immunoglobulin polypeptide chain is contained in multiple gene segments scattered along a chromosome. Each can contribute to a substantial increase in diversity of the germline HC D- and J-region segments. The second mechanism that contributes significantly to the antibody repertoire is the process of somatic hypermutation (SHM). Evidence for Somatic Generation of Antibody Diversity. This article has been cited by other articles in PMC. Abstract. RNA preparations containing mouse κ-chain mRNA have been prepared. The remainder consists of many RNA species, each of which represents a small fraction of the total RNA. Somatic Generation of Immune Diversity 383 technique was available that would allow an analysis of the line structure of specific genes from higher organisms.

Gene counting In the early seventies the technology for purifying a specific eukaryotic mRNA was just becoming available. Furthermore, a method to determine the number It is concluded that the number of germ line genes is too small to account for the observed diversity of antibody molecules. RNA preparations containing mouse κ-chain mRNA have been prepared. The remainder consists of many RNA species, each of which represents a small fraction of the total RNA. The generation of diversity in immunoglobulins Virtually any substance can elicit an antibody response. Furthermore, the response even to a simple antigen bearing a single antigenic determinant is diverse, comprising many different antibody molecules each with a unique affinity, or binding strength, for the antigen and a subtly different specificity. Somatic mutation. Somatic hypermutation is a key mechanism in generating antibody diversity. The details of the mechanisms and regulation of somatic hypermutation are unknown.

In the human, somatic hypermutation occurs in the presence of antigen, unlike in sheep where antigen-independent somatic hypermutation occurs. Generation of Antibody Diversity | IntechOpen Because of the huge diversity, the immunoglobulin repertoire cannot be encoded by static genes, which would explode the genomic capacity comprising about 20,000–25,000 human genes. The Generation of Antibody Diversity Even in the absence of antigen stimulation, a human can probably make more than 10 12 different antibody molecules—its preimmune antibody repertoire. Moreover, the antigen-binding sites of many antibodies can cross-react with a variety of related but different antigenic determinants, making the antibody defense force even more formidable.