Open AccessDifferential inhibitory and activating NK cell receptor levels and NK/NKT-like cell functionality in chronic and recovered stages of chikungunya
Author(s) -
Subrat Thanapati,
Mohini A. Ganu,
Anuradha S. Tripathy
Publication year - 2017
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0188342
Subject(s) - perforin , nkg2d , natural killer t cell , immunology , biology , interleukin 21 , interleukin 12 , natural killer cell , cytotoxic t cell , cd8 , immune system , in vitro , biochemistry
The role of natural killer (NK; CD3 - CD56 + )/NKT (CD3 + CD56 + )-like cells in chikungunya virus (CHIKV) disease progression/recovery remains unclear. Here, we investigated the expression profiles and function of NK and NKT-like cells from 35 chronic chikungunya patients, 30 recovered individuals, and 69 controls. Percentage of NKT-like cells was low in chronic chikungunya patients. NKp30 + , CD244 + , DNAM-1 + , and NKG2D + NK cell percentages were also lower (MFI and/or percentage), while those of CD94 + and NKG2A + NKT-like cells were higher (MFI and/or percentage) in chronic patients than in recovered subjects. IFN-γ and TNF-α expression on NKT-like cells was high in the chronic patients, while only IFN-γ expression on NK cells was high in the recovered individuals. Furthermore, percentage of perforin + NK cells was low in the chronic patients. Lower cytotoxic activity was observed in the chronic patients than in the controls. CD107a expression on NK and NKT-like cells post anti-CD94/anti-NKG2A blocking was comparable among the patients and controls. Upregulated inhibitory and downregulated activating NK receptor expressions on NK/NKT-like cells, lower perforin + and CD107a + NK cells are likely responsible for inhibiting the NK and NKT-like cell function in the chronic stage of chikungunya. Therefore, deregulation of NKR expression might underlie CHIKV-induced chronicity.