FS118, a Bispecific Antibody Targeting LAG-3 and PD-L1, Enhances T-Cell Activation Resulting in Potent Antitumor Activity.

Purpose: Although programmed death-ligand 1 (PD-L1) antibody-based therapy has improved the outcome of patients with cancer, acquired resistance to these treatments limits their clinical efficacy. FS118 is a novel bispecific, tetravalent antibody (mAb) against human lymphocyte activation gene-3 (LAG-3) and PD-L1 with the potential to reinvigorate exhausted immune cells and overcome resistance mechanisms to PD-L1 blockade. Here, using FS118 and a murine surrogate, we characterized the activity and report a novel mechanism of action of this bispecific antibody.

Generation of Fcabs targeting human and murine LAG-3 as building blocks for novel bispecific antibody therapeutics.

The immunoglobulin superfamily protein lymphocyte-activation gene 3 (LAG-3) participates in immune suppression and has been identified as a suitable target for cancer therapies. In order to generate bispecific antibodies targeting LAG-3, Fcabs (Fc-region with antigen binding) targeting human and murine LAG-3 were generated from phage libraries. These Fcabs bind to LAG-3, inhibiting its interaction with MHC class II, and induce IL-2 production in a T cell assay.

Representational difference analysis: critical appraisal and method development for the identification of unique DNA sequences from prokaryotes.

Representational difference analysis (RDA) has great potential for preferential amplification of unique but uncharacterised DNA sequences present in one source such as a whole genome, but absent from a related genome or other complex population of sequences. While a few examples of its successful exploitation have been published, the method has not been well dissected and robust, detailed published protocols are lacking. Here we examine the method in detail, suggest improvements and provide a protocol that has yielded key unique sequences from a pathogenic bacterial genome.