MilleGen proposes to clone and sequence the variable genes of the heavy (VH) and light (VL) chains of rodent (mouse and rat) monoclonal immunoglobulin starting from hybridoma cell lines. The sequencing of the VH and VL retains and immortalizes the mAb which can be crucial for the rescue of unstable hybridoma cell lines. Furthermore, an antibody can be identified by the DNA sequence thus strengthening its patent rights.
One major problem is to obtain the sequence information about the mAb from the occurrence of aberrant mRNAs which are transcribed from rearranged, but not functional heavy and light chain genes in the hybridoma. The aberrant chains greatly dilute the desired antibody sequences, which are the only ones binding the antigen in a pool of non-productive antibody-like sequence. MilleGen has developed a very efficient cloning technique of the complete variable genes of the heavy (VH) and light (VL) chains from the hybridoma cell line. The isolated VH and VL can be engineered to form an antibody fragment or an IgG to test the binding properties of the recombinant antibody and validate the VH and VL sequences coding for the monoclonal antibody.
The recombinant antibody can also be cloned in a screening vector in order to generate a mutant library using the MutaGen™ platform. The molecular evolution technology, MutaGen™, developed by MilleGen (N° WO 02/42311) allows to mimic the somatic hypermutation process, the natural phenomenon of the antibody maturation. MutaGen™ generates mutations on VH and VL in order to select an antibody with a higher affinity. With this technology, the maturation of the affinity of an antibody is obtained without any structural data of the complex antigen-antibody.
