CD30 is a transmembrane cytokine receptor expressed in the cell membranes of activated T cells, B cells at the edge of germinal centers, and some plasma cells. It is expressed in Reed-Sternberg cells in Hodgkin's lymphoma, as well as anaplastic large cell lymphomas and embryonal carcinoma. It is a positive regulator of apoptosis, and protects against autoimmunity. Overexpression causes constitutive expression of nuclear factor-KB, which is considered the molecular basis for the aberrant growth and cytokine expression observed in Hodgkin’s lymphoma. It is a target for the drug brentuximab vedotin. References: Pierce et al. "Diagnostic, prognostic and therapeutic role of CD30 in lymphoma." Expert review of hematology 10.1 (2017): 29-37. https://www.ncbi.nlm.nih.gov/pubmed/27927047