Somatic Cell Hypermutation (SHM)

The basis for Anaptys’ proprietary technology is somatic hypermutation (SHM) – the natural process that occurs in B-cells during the selection and maturation of antibodies.  SHM is a controlled process of introduced changes in the immunoglobulin gene sequence catalyzed by activation-induced cytidine deaminase.

The process of antibody maturation includes both the elaboration of high affinity antibodies dependent upon somatic hypermutation at the IgV (variable) locus, and class-switch recombination at the IgC (constant) gene regions.  Both processes are triggered by targeted deamination of deoxycytidine (dC) to deoxyuridine (dU) residues within the immunoglobulin locus.

Recombination in B cells generates a huge repertoire of antibodies with different antigen binding regions. Sequence diversity is extended through the process of somatic hypermutation. Only those B cells expressing antibodies with stronger antigen binding survive.