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. 2008 Jul;38(7):2034-45.
doi: 10.1002/eji.200738082.

Increased cytotoxicity of CD4+ invariant NKT cells against CD4+CD25hiCD127lo/- regulatory T cells in allergic asthma

Khoa D Nguyen  1 , Chris Vanichsarn, Kari C Nadeau
Affiliations

Increased cytotoxicity of CD4+ invariant NKT cells against CD4+CD25hiCD127lo/- regulatory T cells in allergic asthma

Khoa D Nguyen et al. Eur J Immunol. 2008 Jul.

Abstract

CD4+CD25(hi)CD127(lo/-) regulatory T cells (Treg) have been implicated in the resolution of asthma-associated inflammation while the opposite role of CD4+ invariant NKT (iNKT) cells has been the subject of recent investigations. Studies here focused on mechanisms of interaction between CD4+ iNKT cells and Treg to further explore their roles in allergic asthma (AA). Flow cytometry analysis revealed a significant increase in the expression of the natural cytotoxicity receptors NKp30 and NKp46 by CD4+ iNKT cells in AA subjects compared to healthy controls (HC) and non-allergic asthmatics (NA). Subsequent intracellular staining showed that CD4+ iNKT cells also expressed higher levels of granzyme B and perforin in AA than HC. In in vitro killing assays, AA CD4+ iNKT cells selectively killed autologous Treg, but not CD4+CD25- T cells, more potently than HC and NA counterparts. This increased cytotoxicity positively correlated with asthma severity and granzyme B/perforin expression of CD4+ iNKT cells. Furthermore, it could be abrogated by either inhibition of the granzyme B-/perforin-dependent cell death pathway or oral corticosteroid administration. Altogether, these findings suggest that increased cytotoxicity of CD4+ iNKT cells against Treg might contribute to dysfunctional cellular interactions in AA.

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Conflict of interest statement

Conflict of interest: The authors declare no financial or commercial conflict of interest.

Figures

Figure 1
Figure 1
Purity of Treg and CD4+ iNKT cells. (A) Expression of Vα24 and vβ11 by purified CD4+ iNKT cells in representative HC, AA, and NA samples. (B) Expression of CD25 and FoxP3 by purified Treg and non-Treg in representative HC, AA, and NA samples.
Figure 2
Figure 2
Expression of activating receptors on CD4+ iNKT cells. (A) Percentage of CD4+ iNKT cells that are NKp30hi. (B) Percentage of CD4+ iNKT that are NKp46hi. (C) Percentage of CD4+ iNKT cells that express NKG2D. (D) Percentage of CD4+ iNKT cells that express CD226. Histograms of NKp30, NKp46, NKG2D, and CD226 expressions on CD4+ iNKT cells in representative HC, AA and NA samples. ANOVA was used for statistical analysis. p values represent results from post-ANOVA comparison. Horizontal bars represent median values.
Figure 3
Figure 3
Expression of cytotoxic molecules on CD4+ iNKT cells. (A) Percentage of CD4+ iNKT cells that express granzme A. (B) Percentage of CD4+ iNKT cells that are granzyme Bhi. (C) Percentage of CD4+ iNKT cells that are perforinhi. Histogram of granzyme A, granzyme B, and perforin expressions by CD4+ iNKT cells in representative HC, AA and NA samples. ANOVA was used for statistical analysis. p values represent results from post-ANOVA comparison. Horizontal bars represent median values.
Figure 4
Figure 4
Cytotoxicity of CD4+ iNKT cells against autologous and allogeneic Treg and non-Treg targets. (A) Percentages of target cell death in killing assays of CD4+ iNKT cells against autologous Treg targets. (B) Percentages of target cell death in killing assays of CD4+ iNKT cells against autologous non-Treg targets. (C) Percentages of target cell death in killing assays of CD4+ iNKT cells against autologous Treg targets from different subsets of AA subjects with respect to disease severity. (D) Percentages of target cell death in killing assays of CD4+ iNKT cells against allogeneic Treg targets. Flow cytometric analysis of killing assays at 10:1 ratio of CD4+ iNKT cells to Treg or non-Treg targets. Cell populations represented in histograms were CSFE+ target cells. Cell death in each killing assay was determined by percentage of 7-aminoactinomycin D+CFSE+ cells out of total CSFE+ cells. ANOVA was used for statistical analysis. p values represent results from post-ANOVA comparison. Bar graph represents median values and ranges. Horizontal bars represent median values.
Figure 5
Figure 5
Effects of inhibitors of cell death pathways on CD4+ iNKT cell cytotoxicity. (A) Effects of a granzyme B-blocking antibody in killing assays of CD4+ iNKT cells against Treg. (B) Effects of a perforin-blocking antibody in killing assays of CD4+ iNKT cells against Treg. (C) Effects of a FasL-blocking antibody in killing assays of CD4+ iNKT cells against Treg. (D) Effects of a low-endotoxin IgG1 antibody in killing assays of CD4+ iNKT cells against Treg. (E) Effects of a granzyme B inhibitor and a caspase-8 inhibitor in killing assays of CD4+ iNKT cells against Treg. Data were collected from equal numbers of HC and AA subjects for each of the first four panels. Paired t-tests were used for the first four panels. All AA subjects were used for the last panel. ANOVA was used for statistical analysis of the last panel, p values represent results from paired t-tests or post-ANOVA comparison. Bar graph represents median values and ranges.
Figure 6
Figure 6
Modulation of cytotoxicity of CD4+ iNKT cells by OCS. (A) Effects of OCS on CD4+ iNKT cell-mediated cytotoxicity against autologous Treg in killing assays. (B) Effects of OCS on expression of NKp30 on CD4+ iNKT cells. (C) Effects of OCS on expression of NKp46 on CD4+ iNKT cells. (D) Effects of OCS on expression of granzyme B on CD4+ iNKT cells. (E) Effects of OCS on expression of perforin on CD4+ iNKT cells. Paired t-tests were used for statistical analysis, p values represent results from t-tests.
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References

    1. Sears MR, Burrows B, Flannery EM, Herbison GP, Hewitt CJ, Holdaway MD. Relation between airway responsiveness and serum IgE in children with asthma and in apparently normal children. N. Engl. J. Med. 1991;325:1067–1071. - PubMed
    1. Robinson DS, Hamid Q, Ying S, Tsicopoulos A, Barkans J, Bentley AM, Corrigan C, et al. Predominant TH2-like bronchoalveolar T-lymphocyte population in atopic asthma. N. Engl. J. Med. 1992;326:298–304. - PubMed
    1. Umetsu DT, Dekruyff RH. Immune dysregulation in asthma. Curr. Opin. Immunol. 2006;18:727–732. - PubMed
    1. Robinson DS. The role of regulatory T lymphocytes in asthma pathogenesis. Curr. Allergy Asthma Rep. 2005;5:136–141. - PubMed
    1. Baecher-Allan C, Viglietta V, Hafler DA. Human CD4+CD25+ regulatory T cells. Semin. Immunol. 2004;16:89–98. - PubMed

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