The Unusual Genetics and Biochemistry of Bovine Immunoglobulins.

The Unusual Genetics and Biochemistry of Bovine Immunoglobulins. Adv Immunol. 2018;137:135-164 Authors: Stanfield RL, Haakenson J, Deiss TC, Criscitiello MF, Wilson IA, Smider VV Abstract Antibodies are the key circulating molecules that have evolved to fight infection by the adaptive immune system of vertebrates. Typical antibodies of most species contain six complementarity-determining regions (CDRs), where the third CDR of the heavy chain (CDR H3) has the greatest diversity and often makes the most significant contact with antigen. Generally, the process of V(D)J recombination produces a vast repertoire of antibodies; multiple V, D, and J gene segments recombine with additional junctional diversity at the V-D and D-J joints, and additional combinatorial possibilities occur through heavy- and light-chain pairing. Despite these processes, the overall structure of the resulting antibody is largely conserved, and binding to antigen occurs predominantly through the CDR loops of the immunoglobulin V domains. Bovines have deviated from this general paradigm by having few VH regions and thus little germline combinatorial diversity, but their antibodies contain long CDR H3 regions, with substantial diversity generated through somatic hypermutation. A subset of the repertoire comprises antibodies with ultralong CDR H3s, which can reach over 70 amino acids in length. Structurally, these unusual antibodies form a β-ribbon "stalk" and disulfi...
Source: Advances in Immunology - Category: Allergy & Immunology Authors: Tags: Adv Immunol Source Type: research