https://doi.org/10.1351/goldbook.13199
Member of a subclass of T lymphocytes that provides help (in the form of cytokines and/or cognate interactions) necessary for the expression of effector function by other cells in the immune system.
Note: Helper T cells recognize antigen in association with major histocompatibility complex (MHC) class II gene products. Depending on their capacity to produce various cytokines, one can functionally differentiate Th1 [interleukin-2- (IL-2-) and IFN-γ-producing] and Th2 (interleukins IL-3-, IL-4-, and IL-6-producing) cells.