Natural killer T Cells: A Powerful Via in the Regulation of Non Communicable Chronic Diseases

Carlos Ramirez-Velazquez,Juan Carlos Paredes-Palma,Sandra Vanesa Patzi-Vargas

doi:10.11648/j.cmr.20190806.12

Abstract

The Natural Killer T cells (NKT) constitute a population of T lymphocytes that co-express an antigen receptor (TCR) and a marker of natural killer cells (NK1.1). We have found that after stimulation through TCR, the NKT cells secrete various cytokines that play an important role in the innate immune response and have a fundamental participation in the initial stages of the immune response to many pathogens and tumours. NKT cells belong to a group of autoreactive T cells that are generated in the thymus, which is why they have been found to play an important role in the regulation of different autoimmune diseases, such as type 1 diabetes, systemic lupus erythematosus, multiple sclerosis, and others. Also, in adulthood there is an aging of the immune system known as immunosenescence, where a decrease and alteration of the function of NKT cells has been observed, which leads to a greater oncological, viral and autoimmune diseases. It has also recently been found that these cells participate in bronchial inflammation in patients with allergic asthma as well as in rhinitis and atopic dermatitis; having these cells a clear role in the regulation of various diseases and that has not been studied as a therapeutic target.

Highlights

Natural killer T cells (NKT) represent a group of lymphocytes that participate in an innate immune response.[1] The function of NKT cells has been extensively investigated in recent decades, they have a fundamental participation in the initial stages of immune response to many pathogens and tumours
NKT cells belong to a group of self-reactive T cells that originate in the thymus, play an important role in the regulation of different autoimmune diseases that have been studied in both animal and human models
NKT cells that express γδTCR are found mainly in the liver and represent 24% of the total NKT cells. These cells are increased at birth, having a primary role in the protection of the host in early stages of life until the appearance of NKT cells expressing αβTCR [44] The NKT cells that express a γδTCR are preserved in elder humans, because it presents activation of the CD69 marker and there is no activation of apoptosis via Fas [45]

Summary

Introduction

Natural killer T cells (NKT) represent a group of lymphocytes that participate in an innate immune response. Most NKT cells express an invariant TCR, consisting of the Vα14Jα281 chain and a preferential use of the chains Vβ8.2 (50%), Vβ7 (14%), y Vβ2 (7%); they express NK1.1 markers (CD161), Ly49, CD11a (LFA-1α), CD122, CD28+, CD69+, CD45RB+, chemokine receptors such as CCR2 and CCR6 (5) In humans they express the α homologue chain Vα24Jα18 [8], as well as the chain Vβ11, NKR-P1A (CD161), CD122, CD56, CD57 and other molecules such as CD44 high, CD45RB low, CD62L high, indicators of an activation/memory phenotype, and CD69, early activation marker, CD28+, CD49d/e/f, chemokine receptors such as CCR2, CCR5, CXCR3, CXCR4, CCR6, CXCR6 (Figure 1). This entity is known as immunosenescence that will be briefly discussed in this article

Natural Killer T Cells and Autoimmunity

Natural Killer T Cells and Immunosenescence

Natural Killer T Cells and Allergy

Findings

Conclusion