HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Abstract Full Text (PDF) A correction has been published Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Kenna, T. Articles by Doherty, D. G. Search for Related Content PubMed PubMed Citation Articles by Kenna, T. Articles by Doherty, D. G.

NKT Cells from Normal and Tumor-Bearing Human Livers Are Phenotypically and Functionally Distinct from Murine NKT Cells ¹

Tony Kenna^*, Lucy Golden Mason^*, Steven A. Porcelli, Yasuhiko Koezuka, John E. Hegarty^2,,¶, Cliona O’Farrelly^2,*,¶ and Derek G. Doherty^2,3,||

^* Education and Research Center and Liver Unit, St. Vincent’s University Hospital, Dublin, Ireland; Department of Microbiology and Immunology, Albert Einstein College of Medicine, New York, NY 10461; Pharmaceutical Research Laboratory, Kirin Brewery Co. Ltd., Gunma, Japan; ^¶ Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Ireland; and ^|| Institute of Immunology and Department of Biology, National University of Ireland, Maynooth, Ireland.

	Abstract

Top Abstract Introduction Materials and Methods Results Discussion References

 
A major group of murine NK T (NKT) cells express an invariant V14J18 TCR -chain specific for glycolipid Ags presented by CD1d. Murine V14J18⁺ account for 30–50% of hepatic T cells and have potent antitumor activities. We have enumerated and characterized their human counterparts, V24V11⁺ NKT cells, freshly isolated from histologically normal and tumor-bearing livers. In contrast to mice, human NKT cells are found in small numbers in healthy liver (0.5% of CD3⁺ cells) and blood (0.02%). In contrast to those in blood, most hepatic V24⁺ NKT cells express the V11 chain. They include CD4⁺, CD8⁺, and CD4^-CD8^- cells, and many express the NK cell markers CD56, CD161, and/or CD69. Importantly, human hepatic V24⁺ T cells are potent producers of IFN- and TNF-, but not IL-2 or IL-4, when stimulated pharmacologically or with the NKT cell ligand, -galactosylceramide. V24⁺V11⁺ cell numbers are reduced in tumor-bearing compared with healthy liver (0.1 vs 0.5%; p < 0.04). However, hepatic cells from cancer patients and healthy donors release similar amounts of IFN- in response to -galactosylceramide. These data indicate that hepatic NKT cell repertoires are phenotypically and functionally distinct in humans and mice. Depletions of hepatic NKT cell subpopulations may underlie the susceptibility to metastatic liver disease.

	Introduction

Top Abstract Introduction Materials and Methods Results Discussion References

 
Natural killer T (NKT) lymphocytes share receptor structures and functions of classical T cells and NK cells (1, 2). In mice the majority of NKT cells express a TCR consisting of an invariant -chain, V14J18 (formally V14J281), and one of a limited number of -chains that recognizes glycolipid Ags presented by the MHC class I-like protein CD1d (1, 2, 3, 4). Humans appear to have a more heterogeneous repertoire of NKT cells that can express or TCR and NK cell markers (5). They include classical MHC-restricted T cells (5, 6) as well as CD1d-reactive NKT cells, also known as invariant NKT cells because of their invariant TCR -chain rearrangement, V24J18 (formerly V24JQ), and limited -chain (V11) usage (7, 8). V24J18⁺ NKT cells display structural and functional homology to murine V14J18⁺ NKT cells (9). They can recognize the -anomeric glycolipid -galactosylceramide (GalCer)⁴ and glycosylphosphatidylinositols in a CD1d-restricted manner (9, 10, 11, 12, 13). They can kill a variety of tumor cells (12, 14, 15) and upon TCR stimulation can rapidly produce large amounts of IFN- and IL-4 (8, 16).

V14J18⁺ NKT cells appear to play a key role in antitumor defense in mice. Injection of mice with either IL-12 or GalCer results in tumor rejection by a mechanism that is dependent upon IFN- production and/or antitumor cytotoxicity by NKT cells (17, 18). Furthermore, mice deficient in NKT cells fail to mediate IL-12-induced rejection of tumors (19). Because of the more heterogeneous nature of NKT cells in humans, few studies to date have addressed their role in antitumor immunity in this species. Invariant V14J18⁺ NKT cells constitute 30–50% of murine intrahepatic lymphocytes (1, 2, 20). In contrast, human liver contains only small numbers of V24⁺ NKT cells (21, 22), and the proportion of these cells that express the invariant V24J18 and V11 TCR chains is undetermined. However, T cells expressing the NK receptors CD56, CD161, CD94, and killer Ig-like receptors (KIR), although comprising small proportions of circulating lymphocytes, are substantially enriched in adult human liver (22, 23). In the present study we have enumerated and phenotypically and functionally characterized V24⁺V11⁺ NKT cells from freshly isolated liver specimens taken from healthy donors and from patients with hepatic malignancy. Our results indicate that human hepatic NKT cells are phenotypically and functionally more diverse than murine NKT cells, with only a minor proportion expressing invariant TCR chains. Hepatic V24V11⁺ T cells were found to produce Th1 (IFN- and TNF-), but not Th2 (IL-4), cytokines. Their numbers are significantly lower in patients with hepatic malignancy, suggesting that these cells, like murine V14J18⁺ NKT cells, have antitumor roles in vivo.

	Materials and Methods

Top Abstract Introduction Materials and Methods Results Discussion References

 
Tissue specimens

Wedge liver biopsies (50–100 mg) were obtained from seven healthy donor organs at the time of liver transplantation. Liver biochemistry and histology were normal in all cases. Liver tissue was obtained from 10 patients undergoing resection for hepatic metastases of colonic origin. Wedge biopsies from tumor-bearing tissue were taken 10 cm from the tumor margin and appeared histologically normal. Hepatic mononuclear cell suspensions (HMC) were prepared as described previously (24). Matched PBMC were prepared from each donor and patient by Lymphoprep (Nycomed, Oslo, Norway) density gradient centrifugation. Ethical approval for this study was obtained from the ethics committee at St. Vincent’s University Hospital (Dublin, Ireland).

Flow cytometry

The following mAbs were obtained from BD Biosciences (Oxford, U.K.): IgG1, anti-CD3, anti-CD4, anti-CD8, anti-CD56, anti-CD161, anti-CD25, anti-CD69, anti-CD45RA, and anti-HLA DR. Anti-V24 and anti-V11 were obtained from Immunotech (Marseilles, France). Cells were stained using specific mAb according to standard procedures (22) and were analyzed by flow cytometry using the FACScan CellQuest software (BD Biosciences, San Jose, CA).

Analysis of cytokine production

Freshly isolated HMC were cultured for 6 h with or without 10 ng/ml PMA plus 1 µg/ml ionomycin in 24-well plates at a concentration of 1 x 10⁶ cells/ml. Brefeldin A (10 µg/ml) was added for the last 4 h. Cells were stained as described previously using cell surface anti-V24 and anti-CD3, and intracytoplasmic anti-IFN-, anti-IL-2, anti-TNF-, or anti-IL-4 (BD Biosciences) and were analyzed by flow cytometry (23).

In vitro response to GalCer

HMC (10⁶) were cultured in 24-well tissue culture plates in the presence of GalCer (Kirin Pharmaceutical Research Laboratory, Gunma, Japan), or vehicle as a control, without the addition of further APC. After 48 h culture supernatants were collected from each well. IFN- production by the stimulated HMC was assayed by ELISA according to the manufacturer’s protocols (Quantikine; R&D Systems, Oxon, U.K.).

Statistical analysis

The Mann-Whitney U test was used to compare distributions of cell populations in different groups, and p < 0.05 was taken as significant.

	Results

Top Abstract Introduction Materials and Methods Results Discussion References

 
Va24V11⁺ NKT cells accumulate in human liver

Murine liver contains large numbers (30–50% of CD3⁺ cells) of V14V11⁺ NKT cells (1, 2, 20). We used flow cytometry to determine the frequencies of human T cells that express TCR V24 and V11 chains in seven histologically normal donor livers and matched blood samples (Fig. 1A). Fig. 1B shows that there is no enrichment of V24⁺ T cells in normal human liver relative to blood, since this TCR chain was found to be expressed by a median of 0.61% of peripheral blood CD3⁺ cells and 0.75% of hepatic CD3⁺ cells. However, V24⁺V11⁺ NKT cells were preferentially expanded in normal human liver, accounting for a median of 0.48% of hepatic CD3⁺ cells compared with 0.018% of peripheral blood T cells (p = 0.02; Fig. 1, A and C). Whereas a minority (2.9%) of V24⁺ T cells in blood expressed the V11 chain, up to 90% (median, 64.2%; p = 0.04) of the V24⁺ NKT cells in the liver were V11⁺.

View larger version (31K): [in this window] [in a new window]   FIGURE 1. Small numbers of invariant V24V11+ NKT cells accumulate in human liver. A, Representative flow cytometry dot plot showing V24 and V11 TCR chain expression by gated CD3+ cells freshly isolated from blood and liver of a liver transplant donor. Numbers show percentages of CD3+ cells that express the V24V11 TCR. B and C, Percentages of CD3+ cells in blood and liver of six liver transplant donors expressing V24 (B) and V24V11 (C) TCR chains. Horizontal lines indicate medians. *, p = 0.02.

Phenotypic characterization of hepatic V24⁺ NKT cells

Several studies have examined the phenotypes and functions of subpopulations of human NKT cells following stimulation in vitro with GalCer (9, 10, 12, 13). Here we have examined the phenotypic and activation status of V24⁺ NKT cells ex vivo in the absence of pharmacological manipulation. The phenotypes of nondiseased hepatic V24⁺ NKT cells were compared with those of V24⁺ cells derived from blood from the same individuals (Fig. 2). CD4 and CD8 were expressed by significant numbers of peripheral and hepatic V24⁺ T cells, but while peripheral NKT cells displayed a predominance of CD4⁺ over CD8⁺ and double-negative (DN) CD4^-CD8^- phenotypes, the majority of hepatic V24⁺ cells were CD8⁺ (28.3%) or DN (28.6%; Fig. 2B). A small minority of circulating V24⁺ T cells expressed the NK markers CD56 (median, 3.3% of the total V24⁺ T cells) or CD161 (10.0%), while significantly higher proportions of hepatic V24⁺ T cells expressed CD56 (42.9%; p = 0.03) and CD161 (73.7%; p = 0.02). Analysis of activation status indicated that only a minority of hepatic V24⁺ NKT cells expressed CD25 (median, 5.7%), HLA-DR (15.5%), and CD45RA (7.3%), which are not significantly different from the frequencies of peripheral blood V24⁺ T cells expressing these markers. Significantly higher proportions of hepatic V24⁺ T cells expressed CD69 (median, 60.1%) compared with peripheral V24⁺ T cells (8.3%; p = 0.03; Fig. 2).

View larger version (44K): [in this window] [in a new window]   FIGURE 2. Phenotypic characterization of human hepatic and peripheral blood V24+ T cells. A, Representative flow cytometry dot plot showing CD56, CD161, CD25, CD69, HLA-DR, and CD45RA expression by hepatic V24+ T cells from a liver transplant donor. B, Box plots showing median (horizontal lines), interquartile ranges (shaded areas), and ranges (error bars) of percentages of V24+ T cells in blood and liver of six liver transplant donors expressing CD4+, CD8+, and CD4-CD8- phenotypes, CD56, CD161, CD25, CD69, HLA-DR, and CD45RA. *, p = 0.03 for CD56, p = 0.02 for CD161, and p = 0.03 for CD69.

Decreased numbers of peripheral blood invariant NKT cells in patients with prostate cancer and melanoma have previously been reported (25, 26). We used flow cytometry to quantify V24⁺ and V24V11⁺ T cells among HMC taken from patients undergoing resection for hepatic malignancy. No significant decrease was seen between normal and tumor-bearing liver in terms of total V24⁺ T cells (0.75 vs 0.41% of CD3⁺ T cells; p = 0.23; Fig. 3A). However, the proportion of CD3⁺ cells expressing V24V11 TCR was significantly reduced in tumor-bearing livers compared with healthy livers (median, 0.098 vs 0.48%; p = 0.04; Fig. 3A).

View larger version (34K): [in this window] [in a new window]   FIGURE 3. Invariant NKT cells are selectively depleted in tumor-bearing liver. A, Box plots showing median (horizontal lines), interquartile ranges (shaded areas), and ranges (error bars) of percentages of CD3+ cells in normal donor and tumor-bearing liver expressing V24 TCR chain and V24V11 TCR. *, p = 0.04. B, Box plots showing median, interquartile ranges, and ranges of percentages of hepatic V24+ T cells in six normal donor livers and nine tumor-bearing livers expressing CD4+, CD8+, and CD4-CD8- phenotypes, CD56, CD161, CD25, CD69, HLA-DR, and CD45RA. *, p = 0.05 for CD56, p = 0.03 for CD161, and p = 0.03 for HLA-DR.

Hepatic NKT cells predominantly produce Th1 cytokines

NKT cell lines and clones are known to rapidly produce large amounts of both Th1 and Th2 cytokines (8, 16). We used flow cytometry to examine the cytokine secretion profiles of human hepatic V24⁺ NKT cells in response to in vitro stimulation with PMA and ionomycin (Fig. 4A). The majority of V24⁺ T cells from normal livers produced the inflammatory cytokines, IFN- (median, 83.2%) and TNF- (54.7%) after stimulation (Fig. 4). A minority (4.26%) produced IL-2. While up to 4% of fresh PBMC expressed IL-4 upon stimulation with PMA and ionomycin (data not shown), IL-4 expression by hepatic V24⁺ T cells was not detectable (Fig. 4A). No differences were observed in the cytokine secretion profiles of hepatic V24⁺ T cells from healthy donors and patients with malignancy (Fig. 4B).

View larger version (22K): [in this window] [in a new window]   FIGURE 4. Hepatic NKT cells predominantly produce Th1 cytokines upon stimulation ex vivo. A, Representative flow cytometry dot plot showing IFN-, IL-2, TNF-, and IL-4 expression by hepatic V24+ T cells stimulated for 4 h with PMA and ionomycin. The percentages of V24+ cells that express the cytokines are indicated in the upper right quadrants. B, Median percentages of V24+ cells in four normal donor livers and four tumor-bearing livers that express IFN-, IL-2, TNF-, and IL-4 upon stimulation.

Hepatic response to GalCer stimulation

Since invariant NKT cells were found to be present in such low numbers in both normal and tumor-bearing liver, we aimed to determine whether there was a measurable response to GalCer stimulation in vitro. Freshly isolated HMC and matched PBMC from healthy donors and patients with hepatic malignancy were incubated for 48 h with GalCer, and supernatants were assayed for IFN- and IL-4 production by ELISA. Culture in the presence of GalCer caused a significant increase in the production of IFN- by HMC (389 pg/ml; Fig. 5) without the need for additional APC such as monocyte-derived dendritic cells (12, 13). This increase was not seen when PBMC were treated similarly (27 pg/ml). No IL-4 was detectable in the supernatants of GalCer-stimulated HMC, even though IL-4 was readily detected in PHA-stimulated HMC or PBMC (Fig. 5). HMC from patients with hepatic malignancy secreted levels of IFN- similar to those of normal HMC after stimulation with GalCer (407 pg/ml; Fig. 5).

View larger version (21K): [in this window] [in a new window]   FIGURE 5. HMC respond to GalCer stimulation. Mean IFN- (A) and IL-4 (B) levels released by vehicle-, GalCer-, and PHA-stimulated MNC isolated from blood and livers of five liver transplant donors and from three livers of patients with hepatic malignancy. IL-4 production by GalCer-stimulated HMC was not detected using ELISA sensitive to 1 pg/ml. ND, PHA stimulation of tumor-bearing liver was not performed.

	Discussion

Top Abstract Introduction Materials and Methods Results Discussion References

In the present study we enumerate V24V11⁺ NKT cells in unmanipulated, freshly isolated normal liver and matched blood specimens and show that they account for very low proportions (0.02% in blood and 0.5% in liver) of the total T cell compartment. This compares with frequencies of 4% of peripheral and 30–50% of hepatic T cells that express the homologous V14J18 TCR in mice (1, 2, 20). In contrast to those in blood, the majority of human hepatic V24⁺ cells express the V11 chain associated with the invariant V24J18 TCR of NKT cells. Significant proportions of unstimulated hepatic V24⁺ cells express CD4⁺, CD8⁺, DN, CD56⁺, CD161⁺, CD69⁺, and CD45RA^- phenotypes, similar to those of GalCer-stimulated human NKT cells (10, 12, 13, 15, 18), suggesting that these cells may have previously encountered a natural ligand within the liver. However, in contrast to NKT cells generated by culture in vitro, which are potent producers of IL-4, the majority of freshly isolated V24⁺ T cells exhibited a striking bias toward Th1 cytokine production, producing IFN- and TNF-, but not IL-4, in response to stimulation with phorbol ester or GalCer. Recent studies of GalCer-stimulated human NKT cells (12, 13) and PBMC that stain positively for CD1d-GalCer tetramers (27, 28) have provided evidence that only the CD4⁺ subset of NKT cells can produce both IFN- and IL-4, while DN and CD8⁺ NKT cells produce Th1 cytokines only. We show here that human hepatic NKT cells only exhibit Th1 cytokine phenotypes even though they include significant numbers of CD8⁺, CD4⁺, and DN cells. Human hepatic V24⁺ NKT cells with a predominant Th1 cytokine bias have also been described in patients with chronic hepatitis C infection (29).

Although invariant V24V11⁺ NKT cells, known to recognize glycolipids such as GalCer in the context of CD1d (8, 9, 10), constitute a small proportion of human hepatic T cells, we have shown that significant levels of IFN- are produced by HMC after stimulation with GalCer. While it is likely that some of this IFN- is produced by cells downstream from NKT cells, such as NK cells and CTLs (14, 30), this finding suggests that other noninvariant CD1d-reactive NKT cells may be present in the liver. Noninvariant CD1d-restricted NKT cells that express CD56 and/or CD161 have been detected in human bone marrow (31) and in hepatitis C virus-infected liver (29). However, recent studies (32, 33) have provided evidence that CD1d-GalCer tetramers only stain V24V11⁺ NKT cells, which would argue against the idea of noninvariant hepatic NKT cells recognizing GalCer. NKT cells reactive with CD1 isotypes that are not found in mice, namely CD1a, CD1b, and CD1c, may also reside within the CD56⁺/CD161⁺ T cell compartment of the liver (3, 4).

Our results further indicate that V24V11⁺ NKT cells, but not other V24⁺ cells, are found in significantly lower numbers in histologically normal portions of livers from patients with metastatic liver disease. This reduction in NKT cell numbers could predispose individuals to the development of malignancy or, alternatively, may be the result of activation-induced cell death of these putative antitumor effectors. A decrease in the numbers of NKT cells in peripheral blood has been reported in patients with advanced prostate cancer (25). Compared with controls, PBMC isolated from these patients exhibited diminished expansion of V24V11⁺ NKT cells in response to GalCer and diminished IFN- production by the expanded NKT cells. In contrast, Kawano et al. (26) reported a decrease in V24⁺ NKT cell numbers in the blood of patients with melanoma, but these cells exhibited normal responses to GalCer and normal levels of cytotoxicity. We found that V24V11⁺ NKT cells are reduced in the livers of patients with hepatic malignancy, but that freshly isolated hepatic V24⁺ T cells from healthy donors and patients with hepatic malignancy had similar frequencies of IFN--producing cells. It should be noted that these V24⁺ T cells in the cancer patients include both V11⁺ NKT cells and V11^- non-NKT cells. However, fresh HMC from cancer patients and controls released similar levels of IFN- after stimulation with GalCer in vitro. This suggests that invariant hepatic V24V11⁺ NKT cells from patients with hepatic malignancy release IFN- in response to GalCer, but that downstream events may compensate for the reduction in NKT cell numbers in these patients.

In conclusion, we have demonstrated that the human liver contains small numbers of invariant V24V11⁺ NKT cells, but significant numbers of GalCer-reactive NKT cells, suggesting that the repertoires of hepatic NKT cells are more diverse in humans than in mice. In contrast to in vitro-stimulated murine and human peripheral invariant NKT cells (1, 2, 8, 16), freshly isolated human hepatic V24V11⁺ NKT cells do not produce IL-2 and IL-4 upon stimulation. Depletions of hepatic V24V11⁺ cells, but not other V24⁺ or GalCer-reactive cells, are likely to predispose individuals to metastatic liver disease. However, the differences in numbers, TCR specificities, and functions of hepatic NKT cells in mice and humans need to be taken into account when interpreting the roles of these cells in experimental models of malignancy.

	Acknowledgments

 
We are grateful to our surgical colleagues, Gerry McEntee, Oscar Traynor, Raghu Varadarajan, and Justin Geoghegan, and the liver transplant coordinators, Sheila O’Toole, Aoife Coffey, and Jennifer Fleming, at St. Vincent’s University Hospital for assistance in obtaining liver biopsy samples.

	Footnotes

 
¹ This work was supported by grants awarded by the Irish Health Research Board and Enterprise Ireland.

² J.E.H, C.O’F., and D.G.D. contributed equally to this work.

³ Address correspondence and reprint requests to Dr. Derek G. Doherty, Institute of Immunology and Department of Biology, National University of Ireland, Maynooth, Maynooth, County Kildare, Ireland. E-mail address: derek.g.doherty{at}may.ie

⁴ Abbreviations used in this paper: GalCer, -galactosylceramide; DN, double-negative; CD4^-CD8^- phenotype; HMC, hepatic mononuclear cells; KIR, killer Ig-like receptors.

Received for publication January 27, 2003. Accepted for publication June 9, 2003.

	References

Top Abstract Introduction Materials and Methods Results Discussion References

 

1. Bendelac, A., M. N. Rivera, S. H. Park, J. H. Roark. 1997. Mouse CD1-specific NK1 T cells: development, specificity, and function. Annu. Rev. Immunol. 15:535.[Medline]
2. Kronenberg, M., L. Gapin. 2000. The unconventional lifestyle of NKT cells. Nat. Rev. Immunol. 2:557.
3. Porcelli, S. A., B. W. Segelke, M. Sugita, I. A. Wilson, M. B. Brenner. 1998. The CD1 family of lipid antigen-presenting molecules. Immunol. Today 19:362.[Medline]
4. Porcelli, S. A., R. L. Modlin. 1999. The CD1 system: antigen-presenting molecules for T cell recognition of lipids and glycolipids. Annu. Rev. Immunol. 17:297.[Medline]
5. McMahon, C. W., D. H. Raulet. 2001. Expression and function of NK cell receptors in CD8⁺ T cells. Curr. Opin. Immunol. 13:465.[Medline]
6. Huard, B., L. Karlsson. 2000. KIR expression on self-reactive CD8⁺ T cells is controlled by T-cell receptor engagement. Nature 403:325.[Medline]
7. Porcelli, S., C. E. Yockey, M. B. Brenner, S. P. Balk. 1993. Analysis of T cell antigen receptor (TCR) expression by human peripheral blood CD4^-8^- / T cells demonstrates preferential use of several V genes and an invariant TCR chain. J. Exp. Med. 178:1.[Abstract/Free Full Text]
8. Exley, M., J. Garcia, S. P. Balk, S. Porcelli. 1997. Requirements for CD1d recognition by human invariant V24⁺ CD4^-CD8^- T cells. J. Exp. Med. 186:109.[Abstract/Free Full Text]
9. Brossay, L., M. Chioda, N. Burdin, Y. Koezuka, G. Casorati, P. Dellabona, M. Kronenberg. 1998. CD1d-mediated recognition of an -galactosylceramide by natural killer T cells is highly conserved through mammalian evolution. J. Exp. Med. 188:152.1.[Abstract/Free Full Text]
10. Kawano, T., J. Cui, Y. Koezuka, I. Toura, Y. Kaneko, K. Motoki, H. Ueno, R. Nakagawa, H. Sato, E. Kondo, H. Koseki, et al 1997. CD1d-restricted and TCR-mediated activation of V14 NKT cells by glycosylceramides. Science 278:1626.[Abstract/Free Full Text]
11. Schofield, L., M. J. McConville, D. Hansen, A. S. Campbell, B. Fraser-Reid, M. J. Grusby, S. D. Tachado. 1999. CD1d-restricted immunoglobulin G formation to GPI-anchored antigens mediated by NKT cells. Science 283:225.[Abstract/Free Full Text]
12. Takahashi, T., M. Nieda, Y. Koezuka, A. Nicol, S. A. Porcelli, Y. Ishikawa, K. Tadokoro, H. Hirai, T. Juji. 2000. Analysis of human V24⁺ CD4⁺ NKT cells activated by -glycosylceramide-pulsed monocyte-derived dendritic cells. J. Immunol. 164:4458.[Abstract/Free Full Text]
13. Takahashi, T., S. Chiba, M. Nieda, T. Azuma, S. Ishihara, Y. Shibata, T. Juji, H. Hirai. 2002. Analysis of human V24⁺CD8⁺ NK T cells activated by -galactosylceramide-pulsed monocyte-derived dendritic cells. J. Immunol. 168:3140.[Abstract/Free Full Text]
14. Metelitsa, L. S., O. V. Naidenko, A. Kant, H. W. Wu, M. J. Loza, B. Perussia, M. Kronenberg, R. C. Seeger. 2001. Human NKT cells mediate antitumor cytotoxicity directly by recognizing target cell CD1d with bound ligand or indirectly by producing IL-2 to activate NK cells. J. Immunol. 167:3114.[Abstract/Free Full Text]
15. Kikuchi, A., M. Nieda, C. Schmidt, Y. Koezuka, S. Ishihara, Y. Ishikawa, K. Tadokoro, S. Durrant, A. Boyd, T. Juji, et al 2001. In vitro anti-tumour activity of -galactosylceramide-stimulated human invariant V24⁺ NKT cells against melanoma. Br. J. Cancer 85:741.[Medline]
16. Chen, H., W. E. Paul. 1997. Cultured NK1.1⁺CD4⁺ T cells produce large amounts of IL-4 and IFN- upon activation by anti-CD3 or CD1. J. Immunol. 159:2240.[Abstract/Free Full Text]
17. Smyth, M. J., M. Taniguchi, S. E. Street. 2000. The anti-tumor activity of IL-12: mechanisms of innate immunity that are model and dose dependent. J. Immunol. 165:2665.[Abstract/Free Full Text]
18. Nakagawa, R., I. Nagafune, Y. Tazunoki, H. Ehara, H. Tomura, R. Iijima, K. Motoki, M. Kamishohara, S. Seki. 2001. Mechanisms of the antimetastatic effect in the liver and of the hepatocyte injury induced by -galactosylceramide in mice. J. Immunol. 166:6578.[Abstract/Free Full Text]
19. Cui, J., T. Shin, T. Kawano, H. Sato, E. Kondo, I. Toura, Y. Kaneko, H. Koseki, M. Kanno, M. Taniguchi. 1997. Requirement for V14 NKT cells in IL-12-mediated rejection of tumours. Science 278:1623.[Abstract/Free Full Text]
20. Eberl, G., R. Lees, S. T. Smiley, M. Taniguchi, M. J. Grusby, H. R. MacDonald. 1999. Tissue-specific segregation of CD1d-dependent and CD1d-independent NK T cells. J. Immunol. 162:6410.[Abstract/Free Full Text]
21. Nuti, S., D. Rosa, N. M. Valiante, G. Saletti, M. Caratozzolo, P. Dellabona, V. Barnaba V, S. Abrignani. 1998. Dynamics of intra-hepatic lymphocytes in chronic hepatitis C: enrichment for V24⁺ T cells and rapid elimination of effector cells by apoptosis. Eur. J. Immunol. 28:3448.[Medline]
22. Norris, S., D. G. Doherty, C. Collins, G. McEntee, O. Traynor, J. E. Hegarty, C. O’Farrelly. 1999. Natural T cells in the human liver: cytotoxic lymphocytes with dual T cell and natural killer cell phenotype and function are phenotypically heterogenous and include V24-JQ and T cell receptor bearing cells. Hum. Immunol. 60:20.[Medline]
23. Doherty, D. G., S. Norris, L. Madrigal-Estebas, G. McEntee, O. Traynor, J. E. Hegarty, C. O’Farrelly. 1999. The human liver contains multiple populations of NK cells, T cells, and CD3⁺CD56⁺ natural T cells with distinct cytotoxic activities and Th1, Th2, and Th0 cytokine secretion patterns. J. Immunol. 163:2314.[Abstract/Free Full Text]
24. Curry, M. P., S. Norris, L. Golden-Mason, D. G. Doherty, T. Deignan, C. Collins, O. Traynor, G. P. McEntee, J. E. Hegarty, C. O’Farrelly. 2000. Isolation of lymphocytes from normal adult human liver suitable for phenotypic and functional characterization. J. Immunol. Methods 242:21.[Medline]
25. Tahir, S. M., O. Cheng, A. Shaulov, Y. Koezuka, G. J. Bubley, S. B. Wilson, S. P. Balk, M. A. Exley. 2001. Loss of IFN- production by invariant NK T cells in advanced cancer. J. Immunol. 167:4046.[Abstract/Free Full Text]
26. Kawano, T, T. Nakayama, N. Kamada, Y. Kaneko, M. Harada, N. Ogura, Y. Akutsu, S. Motohashi, T. Iizasa, H. Endo, et al 1999. Antitumor cytotoxicity mediated by ligand-activated human V24 NKT cells. Cancer Res. 15:5102.
27. Gumperz, J. E., S. Miyake, T. Yamamura, M. B. Brenner. 2002. Functionally distinct subsets of CD1d-restricted natural killer T cells revealed by CD1d tetramer staining. J. Exp. Med. 195:625.[Abstract/Free Full Text]
28. Lee, P. T., K. Benlagha, L. Teyton, A. Bendelac. 2002. Distinct functional lineages of human V24 natural killer T cells. J. Exp. Med. 195:637.[Abstract/Free Full Text]
29. Exley, M. A., Q. He, O. Cheng, R. J. Wang, C. P. Cheney, S. P. Balk, M. J. Koziel. 2002. Cutting edge: compartmentalization of Th1-like noninvariant CD1d-reactive T cells in hepatitis C virus-infected liver. J. Immunol. 168:1519.[Abstract/Free Full Text]
30. Ishihara, S., M. Nieda, J. Kitayama, T. Osada, T. Yabe, A. Kikuchi, Y. Koezuka, S. A. Porcelli, K. Tadokoro, H. Nagawa, et al 2000. -Glycosylceramides enhance the antitumor cytotoxicity of hepatic lymphocytes obtained from cancer patients by activating CD3^-CD56⁺ NK cells in vitro. J. Immunol. 165:1659.[Abstract/Free Full Text]
31. Exley, M. A., S. M. Tahir, O. Cheng, A. Shaulov, R. Joyce, D. Avigan, R. Sackstein, S. P. Balk. 2001. A major fraction of human bone marrow lymphocytes are Th2-like CD1d-reactive T cells that can suppress mixed lymphocyte responses. J. Immunol. 167:5531.[Abstract/Free Full Text]
32. Benlagha, K., A. Weiss, A. Beavis, L. Teyton, A. Bendelac. 2000. In vivo identification of glycolipid antigen-specific T cells using fluorescent CD1d tetramers. J. Exp. Med. 191:1895.[Abstract/Free Full Text]
33. Karadimitris, A., S. Gadola, M. Altamirano, D. Brown, A. Woolfson, P. Klenerman, J. L. Chen, Y. Koezuka, I. A. Roberts, D. A. Price, et al 2001. Human CD1d-glycolipid tetramers generated by in vitro oxidative refolding chromatography. Proc. Natl. Acad. Sci. USA 98:3294.[Abstract/Free Full Text]

This article has been cited by other articles:

				M. W.L. Teng, J. A. Westwood, P. K. Darcy, J. Sharkey, M. Tsuji, R. W. Franck, S. A. Porcelli, G. S. Besra, K. Takeda, H. Yagita, et al. Combined Natural Killer T-Cell Based Immunotherapy Eradicates Established Tumors in Mice Cancer Res., August 1, 2007; 67(15): 7495 - 7504. [Abstract] [Full Text] [PDF]

				O. Cohavy and S. R. Targan CD56 Marks an Effector T Cell Subset in the Human Intestine J. Immunol., May 1, 2007; 178(9): 5524 - 5532. [Abstract] [Full Text] [PDF]

				H. Lin, M. Nieda, J. F. Hutton, V. Rozenkov, and A. J. Nicol Comparative gene expression analysis of NKT cell subpopulations J. Leukoc. Biol., July 1, 2006; 80(1): 164 - 173. [Abstract] [Full Text] [PDF]

				Y. Yasunami, S. Kojo, H. Kitamura, A. Toyofuku, M. Satoh, M. Nakano, K. Nabeyama, Y. Nakamura, N. Matsuoka, S. Ikeda, et al. V{alpha}14 NK T cell-triggered IFN-{gamma} production by Gr-1+CD11b+ cells mediates early graft loss of syngeneic transplanted islets J. Exp. Med., October 3, 2005; 202(7): 913 - 918. [Abstract] [Full Text] [PDF]

				M. Heydtmann, P. F. Lalor, J. A. Eksteen, S. G. Hubscher, M. Briskin, and D. H. Adams CXC Chemokine Ligand 16 Promotes Integrin-Mediated Adhesion of Liver-Infiltrating Lymphocytes to Cholangiocytes and Hepatocytes within the Inflamed Human Liver J. Immunol., January 15, 2005; 174(2): 1055 - 1062. [Abstract] [Full Text] [PDF]

				M. Giroux and F. Denis CD1d-unrestricted human NKT cells release chemokines upon Fas engagement Blood, January 15, 2005; 105(2): 703 - 710. [Abstract] [Full Text] [PDF]

				E. Durante-Mangoni, R. Wang, A. Shaulov, Q. He, I. Nasser, N. Afdhal, M. J. Koziel, and M. A. Exley Hepatic CD1d Expression in Hepatitis C Virus Infection and Recognition by Resident Proinflammatory CD1d-Reactive T Cells J. Immunol., August 1, 2004; 173(3): 2159 - 2166. [Abstract] [Full Text] [PDF]

				C. de Lalla, G. Galli, L. Aldrighetti, R. Romeo, M. Mariani, A. Monno, S. Nuti, M. Colombo, F. Callea, S. A. Porcelli, et al. Production of Profibrotic Cytokines by Invariant NKT Cells Characterizes Cirrhosis Progression in Chronic Viral Hepatitis J. Immunol., July 15, 2004; 173(2): 1417 - 1425. [Abstract] [Full Text] [PDF]

				R. Sun, Z. Tian, S. Kulkarni, and B. Gao IL-6 Prevents T Cell-Mediated Hepatitis via Inhibition of NKT Cells in CD4+ T Cell- and STAT3-Dependent Manners J. Immunol., May 1, 2004; 172(9): 5648 - 5655. [Abstract] [Full Text] [PDF]

This Article Abstract Full Text (PDF) A correction has been published Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Kenna, T. Articles by Doherty, D. G. Search for Related Content PubMed PubMed Citation Articles by Kenna, T. Articles by Doherty, D. G.