Interaction between natural killer cells and regulatory T cells: perspectives for immunotherapy

Abstract

Regulatory T (Treg) cells and natural killer (NK) cells are key players in the immune system. The interaction between these two cell types has been reported to be beneficial in healthy conditions such as pregnancy. However, in the case of certain pathologies such as autoimmune diseases and cancer this interaction can become detrimental, as Treg cells have been described to suppress NK cells and in particular to impair NK cell effector functions. This review aims to discuss the recent information on the interaction between Treg cells and NK cells under healthy and pathologic conditions, to describe the specific conditions in which this interaction takes place, the effect of Treg cells on hematopoietic stem cell differentiation and the consequences of this interaction on the optimization of immunotherapeutic protocols.

CML patients with deep molecular responses to TKI have restored immune effectors and decreased PD-1 and immune suppressors

“…60 Tregs dampen immune responses by suppressing the function of effector T and NK cells. 61 When successful TKI therapy reduces the leukemic cell load, suppressor cell activity, and PD-1 expression, there is consequent reactivation of the immune effector response. …”

Analysis of tumor populations and immune system interaction model

“…Unfortunately, these treatments kill normal cells as well as tumor cells. Then, immunotherapy is introduced [1][2][3][4][5][6]. It is based on the generally-accepted hypothesis that the immune system is the best tool humans have for fighting disease [3,[10][11][12][13].…”

“…Therefore, some researchers intensively continue to develop and investigate the interaction between growing tumor and immune system [1][2][3][4][5][6][7][8][9][10][11][12][13]. Majority of the research on immune cells focused on NK cell, T cell and macrophages [3,[5][6][7]10].…”

Frontiers in natural killer cell immunology

“…However, during the past 5 years, significant progress has been made in understanding NK cell biology. In this issue, there are five reviews highlighting recent progress in studying the education of memory NK cells in the liver, 3 the roles of NK cells in immune tolerance, 4 the interactions of NK cells with other immune cells 5,6 and NK cell immunotherapy for tumors. 7 Jiang et al 's 3 review recent advances showing that NK cells can mediate memory responses in both mice and humans.…”

“…5 NK cells cannot produce PGE2 but respond to this molecule, and this review highlights the effects of PGE2 on DC-NK cell crosstalk and the subsequent impact on preventive and pathological immune responses. By contrast, Pedroza-Pacheco et al 6 review the interactions between regulatory T (Treg) cells and NK cells. In tumors, Treg cells may suppress NK cells and, in particular, impair NK cell effector functions.…”