PRL and systemic lupus erythematosus: This increase in the absolute number of TFH cells could give us at least a partial explanation for the association between high levels of PRL and the increase in autoantibodies of the IgG isotype in patients or mice with SLE, as the uncontrolled accumulation of TFH cells might activate autoreactive B cells to produce excessive autoantibodies that cause autoimmune responses [50, 56].