CD1a is a cell surface-associated protein expressed at the "dual-positive" stage of T cell development, which is the stage at which CD4 and CD8 are coexpressed on immature T cells in the thymus. CD1a is expressed on a subset of precursor T lymphoblastic leukemias/lymphomas corresponding to this stage of T cell development. CD1a is also expressed on the great majority of normal and neoplastic Langerhans cells.
Subcellular Localization: Membranous and cytoplasmic
CPT Code(s): 88342 or 88341 (reference only; CPTs may vary)
Turnaround Time: Within 1-2 business days of receipt
Schedule: Monday - Friday
• Formalin-fixed, paraffin-embedded (FFPE) tissue block or cell block - OR -
• 1 unstained slide for each test requested plus 3-4 additional unstained slides cut at 4µm