CD11c (Hairy Cell / NHL Marker)

Hairy cell lymphoma/leukemia characteristically expresses B‑cell markers CD19, CD20 and CD22, plus the classic HCL markers CD11c, CD25, CD103 and CD123. Cells are typically bright for CD45 and surface immunoglobulin. They are usually negative for CD5 and CD10. Ancillary markers like annexin A1 and TRAP activity support the diagnosis but are not CD antigens.

Biomarkers for hairy cell leukemia include an immunophenotype expressing B‑cell markers (CD19, CD20) plus strong CD11c, CD25, CD103 and CD123 positivity; annexin A1 and TRAP (tartrate‑resistant acid phosphatase) are characteristic. Most classic cases harbor the BRAF V600E mutation. Laboratory features often show monocytopenia and pancytopenia with splenomegaly supporting diagnosis.

The confirmatory test for hairy cell leukemia is a bone marrow biopsy with immunophenotyping by flow cytometry showing characteristic B cells positive for CD11c, CD25, CD103 and CD123. Tartrate‑resistant acid phosphatase (TRAP) staining can be supportive. Molecular detection of the BRAF V600E mutation further confirms classic hairy cell leukemia and informs treatment decisions.

The triad of hairy cell leukemia is massive splenomegaly, peripheral cytopenias (especially neutropenia with marked monocytopenia), and circulating “hairy” B lymphocytes on peripheral smear and bone marrow. These cells are typically tartrate‑resistant acid phosphatase–positive and show a characteristic immunophenotype (CD11c, CD25, CD103), which helps confirm the diagnosis. Clinical features often include fatigue, infections, and left upper‑quadrant discomfort.

CD markers used to diagnose lymphoma include B‑cell markers CD19, CD20, CD22 and CD79a; germinal‑center marker CD10; mantle‑cell often shows CD5 with cyclin D1 overexpression; chronic lymphocytic leukemia/small‑cell lymphoma shows CD5 and CD23 co‑expression. T‑cell markers include CD2, CD3, CD5 and CD7. Classical Hodgkin/Reed‑Sternberg cells typically express CD30 and often CD15.

Yes. Hairy cell leukemia is a rare, indolent B‑cell malignancy classified within the non‑Hodgkin lymphomas. It arises from mature B lymphocytes, causes bone marrow infiltration, splenomegaly and cytopenias, and is considered a distinct chronic B‑cell lymphoproliferative disorder. Diagnosis uses blood/marrow immunophenotyping; treatment typically involves purine‑analog chemotherapy and targeted agents.