CD1d expressing dendritic cells (DCs) are good glyco-lipid antigen presenting cells for NKT cells. However, resting B cells are very weak stimulators for NKT cells. Although alpha-galactosylceramide (alpha-GalCer) loaded B cells can activate NKT cells, it is not well defined whether B cells interfere NKT cell stimulating activity of DCs. Unexpectedly, we found in this study that B cells can promote Th1-skewed NKT cell response, which means a increased level of IFN-gamma by NKT cells, concomitant with a decreased level of IL-4, in the circumstance of co-culture of DCs and B Cells. Remarkably, the response promoted by B cells was dependent on CD1d expression of B cells.
Antigen-Presenting Cells ; B-Lymphocytes* ; Coculture Techniques ; Dendritic Cells ; Galactosylceramides ; Interleukin-4 ; Natural Killer T-Cells*

PURPOSE: Invariant natural killer T (iNKT) cells may play an important role in the pathogenesis of asthma in mice and humans. Thus, an agent that modulates the function of iNKT cells may have therapeutic potential to control asthma. We hypothesized that lipopolysaccharide (LPS)-, flagellin-, or CpG-induced changes in the cytokine milieu may modify and even inhibit the function of airway iNKT cells in asthma. METHODS: Because increased alpha-galactosylceramide (GalCer)-induced airway hyperreactivity (AHR) reflects the presence of airway iNKT cells, alpha-GalCer-induced AHR, as well as inflammatory cells and cytokines in bronchoalveolar lavage (BAL) fluid, were determined 24 hours after in vivo treatment with LPS, flagellin, or CpG in naive BALB/c mice. Intracellular IL-4 and IFN-gamma were measured in spleen iNKT cells after in vitro treatment with LPS, flagellin, or CpG. A role for IL-12 following the treatments was determined. RESULTS: Intranasal administration of LPS, flagellin, or CpG reduced development of alpha-GalCer-induced AHR, eosinophilic airway inflammation, and Th1 and Th2 cytokine responses in BAL fluid, while producing IL-12 in BAL fluid. Intraperitoneal administration of IL-12 mAb blocked the suppressive effect of LPS, flagellin, or CpG. In vitro treatment with LPS, flagellin, or CpG reduced production of IL-4 and IFN-gamma from alpha-GalCer-stimulated spleen iNKT cells; these effects were ameliorated by addition of anti-IL-12 mAb. CONCLUSIONS: TLR4, 5, and 9 agonists may suppress the function of airway and spleen iNKT cells via IL-12-dependent mechanisms. Anergy of iNKT cells by IL-12 might play a role in suppression by these TLR agonists.
Administration, Intranasal ; Animals ; Asthma ; Bronchoalveolar Lavage ; Cytokines ; Eosinophils ; Flagellin ; Galactosylceramides ; Humans ; Inflammation ; Interleukin-12 ; Interleukin-4 ; Mice ; Natural Killer T-Cells ; Spleen

An experimental allergic encephalomyelitis was induced by bovine myelin basic protein (MBP) and bovine galactocerebroside (GC) on male guinea pigs. Animals were divided into five experimental and one control groups. Among the five experimental groups, three were inoculated with 75 micrograms, 150 micrograms and 300 micrograms of MBP, respectively, to see the dose dependency of demyelination. The fourth group was inoculated with mixture of 75 micrograms of MBP and 180 micrograms of GC and the fifth group with 180 micrograms GC. All inocula was injected intradermally in emulsion state mixed with equal amount of complete Freund adjuvant. Control group was injected with adjuvant only. Clinical symptoms began to appear from 15th day after inoculation and animals were sacrificed on maximum neurologic deficit or 4 to 5 days after the onset of symptoms. Demyelination was observed in 6 out of 8 animals inoculated with MBP/GC mixture, while only 3 out of 24 animals inoculated with various dosage of MBP showed demyelination. The difference was statistically significant. Serum antibodies to MBP and GC were measured by ELISA method. All of the eight animals inoculated with MBP/GC mixture and two animals inoculated with GC had low titer of anti-GC antibodies, while all animals inoculated with MBP, MBP alone or MBP/GC mixture, had high titer of anti-MBP antibodies. Therefor it is concluded that the demyelination is augmented by GC and is not significantly dose-dependent on MBP.
Animals ; Autoantibodies/*immunology ; Central Nervous System/*immunology/pathology ; Cerebrosides/*immunology ; Dose-Response Relationship, Drug ; Encephalomyelitis, Autoimmune, Experimental/*metabolism/pathology ; Galactosylceramides/*immunology ; Guinea Pigs ; Male ; Myelin Basic Protein/*immunology

An experimental allergic encephalomyelitis was induced by bovine myelin basic protein (MBP) and bovine galactocerebroside (GC) on male guinea pigs. Animals were divided into five experimental and one control groups. Among the five experimental groups, three were inoculated with 75 micrograms, 150 micrograms and 300 micrograms of MBP, respectively, to see the dose dependency of demyelination. The fourth group was inoculated with mixture of 75 micrograms of MBP and 180 micrograms of GC and the fifth group with 180 micrograms GC. All inocula was injected intradermally in emulsion state mixed with equal amount of complete Freund adjuvant. Control group was injected with adjuvant only. Clinical symptoms began to appear from 15th day after inoculation and animals were sacrificed on maximum neurologic deficit or 4 to 5 days after the onset of symptoms. Demyelination was observed in 6 out of 8 animals inoculated with MBP/GC mixture, while only 3 out of 24 animals inoculated with various dosage of MBP showed demyelination. The difference was statistically significant. Serum antibodies to MBP and GC were measured by ELISA method. All of the eight animals inoculated with MBP/GC mixture and two animals inoculated with GC had low titer of anti-GC antibodies, while all animals inoculated with MBP, MBP alone or MBP/GC mixture, had high titer of anti-MBP antibodies. Therefor it is concluded that the demyelination is augmented by GC and is not significantly dose-dependent on MBP.
Animals ; Autoantibodies/*immunology ; Central Nervous System/*immunology/pathology ; Cerebrosides/*immunology ; Dose-Response Relationship, Drug ; Encephalomyelitis, Autoimmune, Experimental/*metabolism/pathology ; Galactosylceramides/*immunology ; Guinea Pigs ; Male ; Myelin Basic Protein/*immunology

Animals ; Female ; Galactosylceramides ; metabolism ; Graft vs Host Disease ; metabolism ; Male ; Mice ; Mice, Inbred BALB C ; Mice, Inbred C57BL ; T-Lymphocytes ; cytology ; Th2 Cells ; cytology

Natural killer T (NKT) cell is a special type of T lymphocytes that has both receptor of natural killer (NK) cell (NK1.1, CD161c) and T cell (TCR) and express a conserved or invariant T cell receptor called Valpha14Jalpha18 in mice or Va24 in humans. Invariant NKT (iNKT) cell recognizes lipid antigen presented by CD1d molecules. Marine-sponge-derived glycolipid, alpha-galactosylceremide (alpha-GalCer), binds CD1d at the cell surface of antigen-presenting cells and is presented to iNKT cells. Within hours, iNKT cells become activated and start to secrete Interleukin-4 and interferon-gamma. NKT cell prevents autoimmune diseases, such as type 1 diabetes, experimental allergic encephalomyelitis, systemic lupus erythematous, inflammatory colitis, and Graves' thyroiditis, by activation with alpha-GalCer. In addition, NKT cell is associated with infectious diseases by mycobacteria, leshmania, and virus. Moreover NKT cell is associated with asthma, especially CD4+ iNKT cells. In this review, I will discuss the characteristics of NKT cell and the association with inflammatory diseases, especially asthma.
Animals ; Antigen-Presenting Cells ; Asthma ; Autoimmune Diseases ; Colitis ; Communicable Diseases ; Encephalomyelitis, Autoimmune, Experimental ; Galactosylceramides ; Humans ; Interferon-gamma ; Interleukin-4 ; Mice ; Natural Killer T-Cells ; Receptors, Antigen, T-Cell ; T-Lymphocytes ; Thyroid Gland ; Thyroiditis ; Viruses

Invariant natural killer T (iNKT) cells develop in the thymus upon recognition of CD1d expressed on developing thymocytes. Although CD4 and CD8 coreceptors are not directly involved in the interaction between CD1d and the T cell receptors (TCRs) of iNKT cells, a conspicuous lack of CD8+ iNKT cells in mice raised the question of whether CD8+ iNKT cells are excluded due to negative selection during their thymic development, or if there is no lineage commitment for the development of murine CD8+ iNKT cells. To address this question, we analyzed iNKT cell-specific TCR Valpha14+ transgenic mice, where the Valpha14 transgene forces the generation of iNKT cells. This allows detailed study of the iNKT cell repertoire. We were able to identify CD8+ iNKT cells which respond to the NKT cell-specific glycolipid ligand alpha-galactosylceramide. Unlike conventional iNKT cells, CD8+ iNKT cells produce predominantly IFN-gamma but not IL-4 upon antigen stimulation. We also confirmed the presence of CD8+ iNKT cells in wild type mice. Our results suggest that CD8+ NKT cells do exist in mice, although their population size is quite small. Their Th1-skewed phenotype might explain why the population size of this subtype needs to be controlled tightly.
Animals ; CD8-Positive T-Lymphocytes/*immunology/metabolism ; Galactosylceramides/immunology ; Interferon-gamma/immunology ; Interleukin-4/immunology ; Mice ; Mice, Inbred C57BL ; Mice, Transgenic ; Natural Killer T-Cells/*immunology/metabolism ; Receptors, Antigen, T-Cell, alpha-beta/*genetics ; Transgenes

Immune reconstitution is crucially relevant for patients receiving hematopoietic stem cell transplantation (HSCT). This study was purposed to investigate the ability of α-GalCer (α-galactosylceramide), a well-known activator of natural killer T cells (NK-T), to enhance immune and hematological reconstitution. Lethally irradiated BALB/c mice were transplanted with allogeneic C57BL/6 bone marrow cells and splenocytes. α-GalCer was administered immediately after HSCT. After transplantation, the weight, activity, hairs, diarrhea and survival time of mice were observed daily; the blood routine test was performed once weekly; the donor chimeras, amount of mononuclear cells in spleen (MNC) and relative levels of CD3(+), CD4(+), CD8(+), B220(+), CD11c(+), CD40(+), CD86(+) and CD80(+) cells were detected by FACS on day 2, 7, 14, 27, 70 after transplantation. The results indicated that the MNC counts and relative levels of CD3(+) and CD4(+) in group treated with α-GalCer on day 2 after transplantation were higher than those in control group; at the same time, the detected donor chimeras were complete recipient type chimeras, then gradually transformed into donor type, on day 7 - 14 donor chimeras in α-GalCer group were enhanced significantly as compared with control group, on day 27 the chimeras in two groups were complete donor type chimeras thereafter to day 70, the MNC count and relative levels of CD3(+), CD4(+), CD8(+), B220(+), CD40(+), CD86(+) cells in α-GalCer group were obviously higher than those in control group, at the same time, the hematopoietic reconstitution in α-GalCer group was accelerated as compared with control group. It is concluded that the α-GalCer administration after allogeneic bone marrow transplantations accelerates immune and hematological reconstitution.
Animals ; Bone Marrow Transplantation ; immunology ; methods ; Chimera ; Female ; Galactosylceramides ; pharmacology ; Leukocyte Count ; Lymphocyte Activation ; drug effects ; Male ; Mice ; Mice, Inbred BALB C ; Mice, Inbred C57BL ; Natural Killer T-Cells ; drug effects ; immunology ; Postoperative Period

This study was purposed to investigate the phenotype, in vitro expansion and cytokine secretion profile of Valpha24(+) NKT cells from cord blood (CB), peripheral blood (PB), and granulocyte colony stimulating factor-mobilized peripheral blood mononuclear cells (G-PBMNCs). Fresh mononuclear cells (MNCs) were isolated by the method of gradient centrifugation and then cultured with alpha-GalCer (100 ng/ml), IL-2 (50 U/ml), IL-15 (50 ng/ml) for 12 days. Valpha24(+) NKT cells were purified by anti-Vbeta11 TCR McAb and goat anti-mouse IgG magnetic beads. The phenotype and purity of Valpha24(+) NKT cells were determined by flow cytometry. Cytokine production was analyzed by ELISA. The results showed that Valpha24(+) NKT cells in CB, PB and G-PBMNCs were expanded by 221.5 (95 - 501), 456.5 (101 - 2207), and 756.38 (82 - 20373)-fold respectively. After stimulation by phorbol-12-myristate-13-acetate (PMA) for 24 hours, IL-4 and IFN-gamma produced by Valpha24(+) NKT cells from CB and PB were 180.33 (144.67 - 2253.48) vs 190.67 (110.07 - 6060.16) ng/ml, 864.33 (401.33 - 3386.67) vs 508.49 (253.82 - 8840.00) ng/ml respectively, with IL-4/IFN-gamma ratio of 0.503 +/- 0.642 vs 0.455 +/- 0.562 respectively. After expansion of Valpha24(+) NKT cells from G-PBMNCs, IL-4 and IFN-gamma produced by Valpha24(+) NKT cells at day 9 and day 12 were 139.08 (7.62 - 606) vs 89.3 (0 - 729.2) ng/ml, 14264.8 (1168 - 18059) vs 14488 (1041 - 18261) ng/ml respectively, with IL-4/IFN-gamma ratio of 0.0531 +/- 0.1081 vs 0.0376 +/- 0.1148 respectively. It is concluded that in presence of IL-2 and IL-15, alpha-GalCer can facilitate the rapid short-term expansion of Valpha24(+) NKT cells from CB, PB, and G-PBMNCs. Valpha24(+) NKT cells from G-PBMNCs show much high potential of expansion in comparison to the counterparts from CB or PB (p < 0.05). The activated Valpha24(+) NKT cells can secrete IFN-gamma and IL-4 in large amounts, with IFN-gamma in particular.
Cell Culture Techniques ; Fetal Blood ; cytology ; Galactosylceramides ; pharmacology ; Humans ; Interferon-gamma ; secretion ; Interleukin-15 ; pharmacology ; Interleukin-2 ; pharmacology ; Interleukin-4 ; secretion ; Leukocytes, Mononuclear ; cytology ; Lymphocyte Activation ; Natural Killer T-Cells ; metabolism

Purpose of this study was to establish an effective method in vitro to proliferate natural killer T (NKT) cells from umbilical cord blood (UCB) and peripheral blood (PB), and to study their different phenotype. Mononuclear cells (MNC) from UCB and PB were cultured in the presence of IL-2 (100 U/ml), with or without alpha-Galcer. TCR Valpha24 Vbeta11 double positive natural killer T-cells (NKT cells) and their other phenotypes were determined by flow cytometry. The results showed that after expansion for 7 days, TCRValphabeta(+) NKT cells from UCB-MNCs increased by (8.74 +/- 4.37) x 10(2) times as much, but most of them did not express NK1.1 and its TCR Vbeta11(+) was higher than TCR Valpha24(+). After expansion for 14 days, TCR Valphabeta(+) NKT cells from PB-MNCs increased by (3.72 +/- 2.01) x 10(2) times, the expression of NK1.1 was high and its TCR Vbeta11(+) was almost equal to TCR Valpha24(+). It is concluded that human TCR Valpha24 Vbeta11 double positive NKT cells can expand by addition of alpha-Galcer. The proliferation efficiency in UCB-MNCs is greater than that in PB-MNCs. Most of the UCB-NKT is NK1.1(-), while the PB-NKT is NK1.1(+), a new subset of NKT cells.
Cell Proliferation ; Cells, Cultured ; Fetal Blood ; cytology ; Galactosylceramides ; pharmacology ; Humans ; Interleukin-2 ; pharmacology ; Killer Cells, Natural ; cytology ; drug effects ; immunology ; Leukocytes, Mononuclear ; cytology ; Phenotype ; T-Lymphocytes, Regulatory ; cytology ; drug effects ; immunology