Use

CD4 is a single chain transmembrane glycoprotein present on T-helper/inducer cells, as well as various monocyte-derived cells such as Langerhans and dendritic cells. Its expression is absent from immature thymocytes and appears during T-cell development. While precursor T‑lymphoblastic lymphomas show variable CD4 expression, most mature T‑cell lymphomas are CD4‑positive, except for aggressive NK‑cell leukemia, extranodal NK‑cell lymphoma, gamma delta T‑cell lymphomas, and enteropathy‑type T‑cell lymphoma.