Neoantigens - the next frontier in precision immunotherapy for B-cell lymphoproliferative disorders.

Broad activation of host T-cell immunity by immune checkpoint blockade, has revolutionized the treatment of some but not all B-cell lymphoproliferative disorders (LPDs). The challenge for next generation immunotherapeutics, is to successfully induce anti-tumor specific T-cell immunity across a range of B-LPDs, without provoking immune-related adverse events. An emerging strategy is to target neoantigens. Neoantigens are immunogenic peptides, unique to malignant cells, that are presented to T-cells via human leukocyte antigens. Neoantigens most commonly arise from non-synonymous mutations but can also be derived from tumor specific alterations along the protein biosynthesis pathway. B-cell LPDs uniquely express a clonal B-cell receptor (BCR) idiotype, consisting of immunoglobulin genes that undergo recombination and somatic hypermutation. Notably, the BCR idiotype can also give rise to 'immunoglobulin neoantigens'. Here, we provide an overview of current strategies to identify and validate immunoglobulin and non-immunoglobulin neoantigens as well as summarizing studies investigating neoantigens within B-cell LPDs.