CD4 and neoplasm: In addition to its well-documented effects on APCs, tumor-derivedTGF-β can also directly inhibit T cell differentiation and function.49,50 Furthermore, the TDLN sees preferential differentiation of tumorantigen-specific CD4+ T cells into Tregs over effectorT cells, even at early stages of tumor growth.51 Perhaps most notoriously, tumor presence is associatedwith increased expression of immune checkpoints in the TDLN.