Wilms tumor protein 1 (WT1)-derived peptides presented on Human Leukocyte Antigen (HLA) class I and II (WT1-HLA complex)

Wilms tumor protein 1 (WT1) is a zinc-finger transcription factor that plays a critical role in cell growth and differentiation. While its expression is limited in healthy adult tissues, it is highly overexpressed in various hematological malignancies and solid tumors, making it a prime target for immunotherapy (Cheever et al., 2009, Clin Cancer Res). WT1-derived peptides are processed intracellularly and presented on the cell surface by Human Leukocyte Antigen (HLA) Class I and Class II molecules. These peptide-HLA complexes are recognized by the T-cell receptors (TCRs) of CD8+ and CD4+ T lymphocytes, respectively (Oka et al., 2004, J Clin Oncol). Therapeutic strategies targeting these complexes include peptide vaccines designed to stimulate the patient's own immune system and adoptive cell therapies using T-cells engineered with WT1-specific TCRs. Because WT1 is an intracellular protein, its presentation via HLA is the primary mechanism by which the immune system can identify and eliminate WT1-expressing malignant cells (Maslak et al., 2018, Blood Adv). Clinical development often focuses on specific HLA alleles, such as HLA-A*02:01, to ensure proper peptide presentation and recognition. Safety considerations include potential on-target effects on normal tissues like the kidney where WT1 is physiologically expressed (Rosenfeld et al., 2003, Blood).

Other names

WT1-pMHCWT1 peptide-MHC complexWilms tumor 1 antigen peptidesWT1-derived epitopesWT1-HLA-A*02:01 complex

The mechanism of action involves the recognition of the Wilms tumor protein 1 peptide-HLA complex by T-cell receptors. Vaccines like Galinpepimut-S induce an active immune response by presenting these peptides to endogenous T cells, whereas TCR-T therapies provide exogenously engineered T cells that directly bind the complex on tumor cells, triggering the release of cytotoxic granules and inflammatory cytokines to induce apoptosis (Cheever et al., 2009; Oka et al., 2004).