Development of human monoclonal antibodies: A review

Immunogenicity of Innovative and Biosimilar Monoclonal Antibodies

The development of hybridoma technology for producing monoclonal antibodies (mAbs) by Kohler and Milstein (1975) counts as one of the major medical breakthroughs, opening up endless possibilities for research, diagnosis and for treatment of a whole variety of diseases. Therapeutic mAbs were introduced three decades ago. The first generation of therapeutic mAbs of murine origin showed high immunogenicity, which limited efficacy and was associated with severe infusion reactions. Subsequently chimeric, humanized, and fully human antibodies were introduced as therapeutics, these mAbs were considerably less immunogenic. Unexpectedly humanized mAbs generally show similar immunogenicity as chimeric antibodies; based on sequence homology chimeric mAbs are sometimes more “human” than humanized mAbs. With the introduction of the regulatory concept of similar biological medicines (biosimilars) a key concern is the similarity in terms of immunogenicity of these biosimilars with their originators. This review focuses briefly on the mechanisms of induction of immunogenicity by biopharmaceuticals, mAbs in particular, in relation to the target of the immune system.

Receptors and signaling mechanisms for B-lymphocyte activation, proliferation and differentiation--insights from both in vivo and in vitro approaches

During the last three decades, a number of B-lymphocyte specific surface antigens have been defined some of which may also show activation/differentiation specific expression. Here, we review the various signaling events and the receptor-ligand interactions for B-cell development, activation and differentiation. Our discussion and presentation include reviewing the in vivo and in vitro mechanisms. Focus is on the experiments that give us valuable insights into the B cell signaling mechanisms in vitro. Three significant pathways in B-cell development - c-Kit, FLT-3 and IL-7 signaling pathways are elucidated upon. Both antigen dependent and antigen independent mechanisms of B cell stimulation are also reviewed.

Veterinary sources of nonrodent monoclonal antibodies: interspecific and intraspecific hybridomas

The generation of monoclonal antibodies from species other than rats and mice has developed slowly over the last 20 years. The advent of antibody engineering and realization of the advantages of nonmurine antibodies, in terms of their superior affinities and specificities, and their potential as components of human and veterinary therapeutics has increased their relevance recently. There have been significant advances in the development of myeloma and heteromyeloma fusion partners. This is an opportune moment to consolidate experiences of MAb production across the range of species of veterinary interest and place it into context with other developments in the field of monoclonal antibodies. The background to the development of antibodies from species other than the mouse is discussed. The species and antigens used to date are reviewed, as are the methods and results reported. A suggested protocol is provided for first attempts to exploit the huge potential of this aspect of hybridoma technology and suggestions are made for its further expansion.