CD7 (Pan T Cell / Early Myeloid Cell Marker)

CD7 is a transmembrane glycoprotein expressed primarily on thymocytes, mature T lymphocytes and natural killer (NK) cells. It serves as an early T‑cell lineage marker in immunophenotyping and flow cytometry, useful for identifying normal T/NK populations and diagnosing T‑cell leukemias or lymphomas, where CD7 may be underexpressed or lost. It can aid prognosis and treatment decisions.

Yes. CD25 (the IL-2 receptor α chain) is widely used as an early activation marker: it is rapidly upregulated on activated T cells within hours, enabling high‑affinity IL‑2 signaling and proliferation. However, CD25 is constitutively high on regulatory T cells, so its presence alone doesn’t always indicate recent activation without additional markers or functional context.

CD7 positive means cells express the CD7 protein on their surface, a marker typically found on T lymphocytes and natural killer cells. In laboratory tests (flow cytometry or immunohistochemistry), CD7 positivity supports T‑cell lineage identification and helps diagnose or classify lymphoid disorders. Loss or abnormal CD7 expression can be clinically significant in certain T‑cell leukemias and lymphomas.

Yes — CD47 is broadly expressed on T cells. It acts as a "self" or "don't‑eat‑me" signal via SIRPα on phagocytes and also influences T‑cell activation, migration, survival and homeostasis. CD47 is present on naïve T cells and is often upregulated after activation; interactions with thrombospondin‑1 and SIRPα modulate immune responses and phagocytic clearance.

CD7 is an early T‑cell surface marker; loss or abnormal expression is associated with T‑cell malignancies such as T‑cell acute lymphoblastic leukemia, peripheral T‑cell lymphoma, and cutaneous T‑cell lymphomas (mycosis fungoides and Sézary syndrome). Aberrant CD7 patterns are used diagnostically and for monitoring T‑cell lymphoproliferative disorders and can sometimes appear in reactive T‑cell conditions.

Immunophenotyping uses CD markers to classify leukemias. B‑cell ALL: CD19, CD10, CD22, CD79a, often CD34; T‑cell ALL: CD2, CD3, CD5, CD7 (±CD1a, CD4, CD8). AML: myeloid markers CD13, CD33, CD117, often CD34; monocytic AML shows CD14/CD64. CLL characteristically shows CD19+CD5+ with CD23 and weak surface immunoglobulin. Hairy cell leukemi