Umbilical Cord Blood Natural Killer Cells, Their Characteristics, and Potential Clinical Applications

Anushruti Sarvaria,Aurore Saudemont,Dunia Jawdat,J Alejandro Madrigal

doi:10.3389/fimmu.2017.00329

Abstract

Natural killer (NK) cells are lymphocytes of the innate immune system able to kill different targets such as cancer cells and virally infected cells without prior activation making then attractive candidates for cancer immunotherapy. Umbilical cord blood (UCB) has become a source of hematopoietic stem cells for transplantation but as we gain a better understanding of the characteristics of each immune cell that UCB contains, we will also be able to develop new cell therapies for cancer. In this review, we present what is currently known of the phenotype and functions of UCB NK cells and how these cells could be used in the future for cancer immunotherapy.

Highlights

Natural killer (NK) cells are lymphocytes of the innate immune system that exhibit cytotoxicity toward cancer cells and virus-infected cells and have the capacity to produce cytokines such as interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) in response to stimuli
NK cells are defined as CD56+CD3− cells and can be divided into two main subsets according to their expression of CD56 and CD16
This review focuses on providing an overview of the characteristics of Umbilical cord blood (UCB) NK cells compared to NK cells from peripheral blood (PB) and explain how they could be used as a cell therapy to cancer

Summary

INTRODUCTION

Natural killer (NK) cells are lymphocytes of the innate immune system that exhibit cytotoxicity toward cancer cells and virus-infected cells and have the capacity to produce cytokines such as interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) in response to stimuli. This allows for donor and recipient HLA-matched UCBT and mismatching between KIRs and their ligands, maintaining the appropriate matching required for HSCT but providing NK cell alloreactivity, which triggers NK cell activation leading to tumor cell lysis [42] This phenomenon of NK cell alloreactivity was proposed as beneficial in reducing relapse after HSCT; variable results have been reported from different studies [4, 43,44,45,46,47]. As they are immature and have lower functionality as compared to PB NK cells; taking UCB NK cells to the clinics will require a prior activation/expansion step. Another trial, oNKord®, is currently ongoing testing the use of NK cells produced in vitro from UCB CD34+ cells in patients with AML (EudraCT number 2010-018988-41)

CONCLUDING REMARKS

Findings

Non-HSCT