Leishmania-specific T-cell receptor-peptide-MHC complex (Leishmania TCR-pMHC)

The Leishmania-specific T-cell receptor-peptide-MHC (TCR-pMHC) complex is the primary molecular interface for the host's adaptive immune recognition of Leishmania parasites [1, 9]. This complex is formed by the interaction between a T-cell receptor (TCR) on a T lymphocyte and a parasite-derived peptide presented by a Major Histocompatibility Complex (MHC) molecule on the surface of an antigen-presenting cell (APC), such as a macrophage or dendritic cell [2, 10]. The successful formation and signaling of this complex are critical for the induction of a protective Th1 immune response, which involves the secretion of interferon-gamma (IFN-gamma) to activate macrophages for the destruction of intracellular amastigotes [4, 5]. Leishmania parasites have developed sophisticated evasion strategies to disrupt this interaction, such as downregulating MHC class II expression or sequestering antigens within the phagolysosome [3, 18]. Therapeutic approaches targeting this complex include the development of vaccines like ChAd63-KH and LEISH-F1 that utilize immunodominant epitopes to prime T cells, as well as experimental TCR-like antibodies (e.g., 2C44) and altered peptide ligands (e.g., LACK N-164) designed to modulate or visualize the immune response in leishmaniasis [8, 12, 20, 25].

Other names

Leishmania-specific T-cell receptors and peptide–MHC complexes on antigen-presenting cellsLeishmania antigen-MHC-TCR complexLeishmania-specific immunological synapseLeishmania pMHC-TCR complexLeishmania-specific TCR-pMHC

Vaccines and immunotherapies targeting this complex work by promoting the presentation of parasite antigens on MHC molecules and the subsequent activation of specific T-cell receptors, leading to a Th1-mediated immune response and macrophage activation.