Modulation of the CD40–CD40 ligand interaction using human anti‐CD40 single‐chain antibody fragments obtained from the n‐CoDeR phage display library

Abstract

SUMMARYCD40 plays a central regulatory role in the immune system and antibodies able to modulate CD40 signalling may consequently have a potential in immunotherapy, in particular for treatment of lymphomas and autoimmune disease like multiple sclerosis. As a first step to achieve this goal, we describe the selection and characterization of a novel set of fully human anti-CD40 antibody fragments (scFv) from a phage display library (n-CoDeR). In order to determine their biological potential, these antibody fragments have been analysed for their ability to promote B-cell activation, rescue from apoptosis and to block the CD40 -CD40 ligand (CD40L) interaction. The selected cohort of human scFv could be subcategorized, each expressing a distinct functional signature. Thus scFv were generated that induced B-cell proliferation, rescued B cells from apoptosis and blocked the CD40 -CD40L interaction to different extents. In particular, one of the scFv clones (F33) had the ability to abrogate completely this interaction. The epitope recognition patterns as well as individual rate constants were also determined and the affinity was shown to vary from low to high nanomolar range. In conclusion, this panel of human anti-CD40 scFv fragments displays a number of distinct properties, which may constitute a valuable source when evaluating candidates for in vivo trials.

The Human Agonistic CD40 Antibody ADC-1013 Eradicates Bladder Tumors and Generates T-cell–Dependent Tumor Immunity

“…To translate these findings into the clinic, we set out to engineer a CD40 agonistic antibody (18,19), ADC-1013, using Fragment INduced Diversity (FIND; ref. 20).…”

A large semi-synthetic single-chain Fv phage display library based on chicken immunoglobulin genes

“…Recombinant antibodies derived from phage display libraries [1-10] are by now well established in medicine and biotechnology. A major objective of recombinant antibody research so far has been to develop new therapeutic agents for use in human patients.…”

Identification of a Strongly Activating Human Anti-CD40 Antibody That Suppresses HIV Type 1 Infection

“…The binding properties of the different anti-CD40 antibodies varied 20-fold between the strongest binder, A2-54, and the weakest binder F33; however, the ranking order did not correlate with the previously determined monovalent affinity for scFvs. 20,21 This difference is probably due to the steric hindrance of the larger IgG molecules (5.4 times higher molar weight) for binding to cell surface-expressed CD40. It appears that this effect may depend on the binding domain of the antibody, since F33, which binds to the domain located closest to the cell surface, binds poorly to CD40 ϩ cells despite its high affinity in the scFv format.…”

“…20,21 Antibodies obtained from this library have been demonstrated to be well tolerated, and in contrast to antibodies of murine origin, they do not elicit the human antimouse (HAMA) response found in most patients. 22 To date, several monoclonal anti-CD40 antibodies are in clinical trials for indications such as autoimmunity and cancer; 16,17,23 however, only one of them, CHIR-12.12, is a human antibody derived from Xeno mice.…”

“…22 To date, several monoclonal anti-CD40 antibodies are in clinical trials for indications such as autoimmunity and cancer; 16,17,23 however, only one of them, CHIR-12.12, is a human antibody derived from Xeno mice. 17 In this study, we have converted several human anti-CD40 scFv 20,21 to the IgG1 format and analyzed their binding characteristics and functional activity. Our results demonstrate that the antibodies have a wide variety of binding properties and functional effects, and that the most potent activating antibody has the capacity to suppress HIV infection, making these fully human antibodies potential therapeutic candidates.…”