HLA-DR

Synonyms

Class II histocompatibility antigen

  • Tech Only CPT
  • Tech Pro CPT
  • PowerPath Code HLA
  • Schedule Monday - Friday
  • Turn Around Time Within 1-2 business days of receipt
  • Disease State Blastic Plasmacytoid Dendritic Cell Neoplasm
  • Methodology IHC

Specimen Requirements

Formalin-fixed, paraffin embedded tissue block or cell block, or 1 unstained charged slide for each test requested plus 3-4 additional unstained slides cut at 4 microns. Adequate space on each slide for control tissue is required.

Diagnostic Utility

Identifies: HLA-DR (class II histocompatibility antigen). Expressed in lymphomas and leukemias, both myeloid and lymphoid. Examples include acute myeloid leukemias (AML), and chronic myelomonocytic leukemias (CMML). Expression varies in each neoplasm, depending on various factors, including cell maturity and differentiation. HLA-DR has been shown to be consistently expressed in most AMLs of non-M3 (Acute promyelocytic or APL) type, and has been shown to be helpful in differentiating myeloblastic from promyelocytic variants.
Subcellular Localization: Membranous