Human Leukocyte Antigen complex (HLA) (HLA)

The Human Leukocyte Antigen (HLA) system, also known as the Major Histocompatibility Complex (MHC) in humans, is a critical cluster of genes on chromosome 6 that encodes surface glycoproteins essential for immune regulation [1]. These molecules are divided into Class I (HLA-A, -B, -C) and Class II (HLA-DR, -DP, -DQ), which present peptide antigens to CD8+ and CD4+ T cells, respectively, to facilitate self-nonself recognition [2]. The target description provided refers to the complex immunomodulatory mechanism where cells, such as Mesenchymal Stem Cells (MSCs), interact with multiple immune and tissue cells via these HLA molecules and the secretion of paracrine factors like TGF-beta and IL-10 [3]. This system is a primary determinant of transplant compatibility and plays a central role in the pathogenesis of autoimmune disorders and the immune evasion strategies of various cancers [4]. Therapeutic interventions, including cell-based therapies like Remestemcel-L, utilize or modulate this system to suppress pathological inflammation or prevent Graft-versus-Host Disease (GvHD) [5]. Understanding the interplay between HLA surface expression and paracrine signaling is vital for developing targeted immunotherapies and improving outcomes in regenerative medicine.

Other names

Major Histocompatibility ComplexMHCHLA-family surface moleculesHuman Leukocyte Antigen systemMHC Class IMHC Class II

Modulation of T-cell activation and immune homeostasis through antigen presentation and paracrine signaling pathways.