Killer cells & helper cells are pa of -
The category of effector T cell is a broad one that includes various T cell types that actively respond to a stimulus, such as co-stimulation. This includes helper, killer, regulatory, and potentially other T cell types. Reff: Ananthanarayanan & Panikers textbook of microbiology 9th edition pg: 135
B cells
T cells
Monocytes
Macrophages
Immunology