Thymic-shared antigen-1 (TSA-1). A lymphostromal cell membrane Ly-6 superfamily molecule with a putative role in cellular adhesion.
The seeding and colonization of the thymus by bone marrow stem cells and the maturation of these cells into mature T lymphocytes are dependent on cell-surface recognition events between different cell lineages within the thymic microenvironment. Positive and negative selection processes within the thymus produce a peripheral T-cell repertoire capable of recognizing peptides derived from foreign antigen bound to self MHCmolecules. In addition to the TCR/MHC-peptide interaction, many other cell-surface molecules act in concert to regulate the kinetics of cellular interactions and intracellular signaling events during thymopoiesis. We have investigated the complexity of the thymic stroma by using monoclonal antibodies to clone cell-membrane molecules of thymic stromal cells. Thymic-shared antigen-1 (TSA-1) is a molecule of interest because it is expressed by both immature thymocytes and stromal cells. We report herein the structural and evolutionary relationships between TSA-1 and molecules of the Ly-6 superfamily (Ly-6SF), and present evidence that TSA-1 functions as a cell-surface receptor by binding a cognate cell target molecule on the surface of a subset of thymocytes.
Walter & Eliza Hall Institute of Medical Research, Victoria, Australia.
B J
BJ
Classon
R L
RL
Boyd
D000595:Amino Acid Sequence; D000950:Antigens, Ly / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D002448:Cell Adhesion; D008969:Molecular Sequence Data; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D015398:Signal Transduction; D017154:Stromal Cells / Q000737:chemistry; D013601:T-Lymphocytes / Q000737:chemistry*
D000950:Antigens, Ly; D011993:Recombinant Fusion Proteins