For 10 points, name these lymphocytes that come in cytotoxic and helper varieties.
Adoptive cell transfer usually entails transfer of these cells. The zeta chain of a protein expressed by these cells is fused to a single-chain variable fragment to create a chimeric receptor called a CAR  (car) . FOXP3 governs development of the "regulatory" type of these cells. These cells' receptors undergo VDJ recombination but not somatic hypermutation. Professional APCs like dendritic cells (*)  present peptide-protein complexes called MHCs on their surfaces to these cells. Most interleukins are secreted by these cells, which are canonically divided into CD4 or CD8 positive. These cells undergo positive selection while maturing in the thymus. For 10 points, name these lymphocytes that come in cytotoxic and helper varieties.
Adoptive cell transfer usually entails transfer of these cells.
T  cells [or  T  lymphocytes; or specific types of T cells]