Cell-surface protein-protein and receptor-ligand interfaces on mononuclear cells and their partner cells

The 'Cell-surface protein-protein and receptor-ligand interfaces on mononuclear cells and their partner cells' is a biological pathway (Reactome ID: R-HSA-446343) that describes the intricate molecular crosstalk between mononuclear leukocytes—such as T cells, B cells, and monocytes—and their various partner cells, including endothelial cells and antigen-presenting cells (Reactome, 2024). This system includes critical interactions such as the binding of integrins (e.g., LFA-1) to intercellular adhesion molecules (e.g., ICAM-1) and the engagement of T-cell receptors with MHC-peptide complexes, which are fundamental to the immune system's ability to survey tissues and execute targeted effector functions (NCBI, 2021). While the term describes a broad biological system rather than a single molecular target, it encompasses many high-value therapeutic targets used in modern medicine, such as checkpoint inhibitors and adhesion blockers. Dysregulation of these interfaces is a hallmark of chronic inflammation, transplant rejection, and malignancy, making the pathway a central focus for immunotherapeutic intervention (PubMed, 2022). Understanding these interfaces is vital for developing therapies that precisely control immune cell trafficking and activation in various disease states.

Other names

Mononuclear cell surface interactionsImmune cell-cell interfacesReactome Pathway R-HSA-446343Leukocyte-endothelial cell interactions

Modulation of immune cell activation, adhesion, and migration through the inhibition or activation of specific receptor-ligand pairs within the mononuclear cell interface (e.g., blocking PD-1/PD-L1 or alpha-4 integrins).