OBJECTIVETo investigate the change of B-cell activating factor of the TNF family (BAFF) and regulatory T-cells (Tregs) before and after high-dose dexamethasone(HD-DXM) therapy and assess the effect of BAFF on Treg cells in immune thrombocytopenic purpura (ITP).

METHODSThe plasma BAFF concentration was measured by ELISA, and Treg cell numbers by flow cytometry.

RESULTSThe plasma BAFF level \[(599.70 +/- 199.40) pg/ml\] was significantly increased (P < 0.05), and the percentage of Treg cells \[(1.56 +/- 0.73)%\] was significantly decreased (P < 0.01) in ITP patients before treatment as compared with that in controls \[(454.5 +/- 132.5) pg/ml and (4.08 +/- 1.08)%, respectively\]. After treatment with HD-DXM, the plasma BAFF level \[(296.9 +/- 119.7) pg/ml\] was significantly decreased (P < 0.01), and the percentage of Treg cells \[(5.94 +/- 2.22)%\] was significantly increased (P < 0.01). The BAFF level and Treg proportion had no significant correlation with platelets count (P > 0.05). In in vitro assays, no difference was found in the number of Treg cells between rhBAFF0 group and rhBAFF20 group \[(1.53 +/- 0.69)%, (1.49 +/- 0.67)%, P = 0.89)\].

CONCLUSIONBAFF level was increased and Treg cells decreased in ITP patients. HD-DXM might play a role in ITP treatment by down-regulating BAFF expression and up-regulating Treg cells number. BAFF had no influence on the number of Treg cells.

B-Cell Activating Factor ; Dexamethasone ; administration & dosage ; Humans ; Interleukin-4 ; Purpura, Thrombocytopenic, Idiopathic ; immunology ; T-Lymphocytes, Regulatory ; immunology

This study was aimed to investigate the effect of dexamethasone (Dex) on immunosuppressive ability of mesenchymal stem cells (MSC) during expansion and differentiation of MSC. MSC were cultured in 96-well flat-bottom plates. Proliferation assays were performed by using the BrdU colorimetric ELISA Kit. To explore the effect of Dex on MSC immunosuppressive ability, MSC were firstly cultured in complete culture medium for 14 d with Dex (10 nmol/L), and then, peripheral blood mononuclear cells (PBMNC) were co-cultured with MSC in 96-well flat-bottom plates for 3 d. Phytohemagglutinin A (PHA, 10 µg/ml) was used to stimulate activation of PBMNC. The concentrations of IFN-γ in culture supernatants was detected by ELISA. The results indicated that there was no obvious difference in representative phenotypes of MSC between experimental and control groups after MSC were treated with low concentration of Dex (10 nmol/L) for 14 d, but the suppression of Dex-treated MSC on lymphocyte activation in same concentration of cells was significantly reduced as compared with control group. After the Dex-treated MSC were co-cultured with IFN-γ for 12 h, the immunoregulatory ability of MSC was recovered in a certain degree. It is concluded that the Dex impairs the immunosuppressive ability of MSC, the IFN-γ can protect and reverse the immunosuppressive ability of MSC impaired by Dex, so that, when the immunoregulatory activity of MSC is investigated, it is necessary to avoid adding Dex in the culture medium.
Cells, Cultured ; Dexamethasone ; adverse effects ; Humans ; Immune Tolerance ; drug effects ; Interferon-gamma ; immunology ; Leukocytes, Mononuclear ; Lymphocyte Activation ; immunology ; Mesenchymal Stromal Cells ; cytology ; drug effects ; immunology

Toxoplasma gondii has been shown to result in life-threatening encephalitis in immunocompromised patients after reactivation of dormant parasites. In order to obtain information on immune responses related to this phenomenon, BALB/c mice were infected with 25 cysts of the 76K strain of T. gondii, then, treated orally with dexamethasone (Toxo/Dexa-treated group) in order to reactivate the chronic toxoplasmosis. None of the T. gondii-infected mice died during the experimental periods, whereas the Toxo/Dexa-treated mice evidenced a significant attenuation of survival periods. Toxoplasma-specific IgG2a, IgA and IgM titers in sera were significantly depressed in the Toxo/Dexa-treated mice; however, the IgG1 sera titers were similar to those seen in the Toxoplasma-infected mice. The percentages of CD4+ and CD8 alpha + T cells in the Toxo/Dexa-treated mice were significantly reduced 2 weeks after dexamethasone treatment. IFN-gamma and IL-10 production levels in the Toxo/Dexa-treated mice were depressed significantly, whereas IL-4 production was increased temporarily. The expression levels of the Toxoplasma-specific P30 and B1 genes were found to have been increased in the Toxo/Dexa-treated mice in comparison with the Toxoplasmainfected mice. Collectively, the findings of this study demonstrate that reactivation of murine toxoplasmosis as the result of dexamethasone treatment induced a depression in Th1 immune responses, whereas Th2 immune responses were not significantly influenced.
Toxoplasmosis/*immunology/parasitology ; Toxoplasma/*immunology ; Th2 Cells/immunology ; Th1 Cells/immunology ; Mice, Inbred BALB C ; Mice ; Immunoglobulins/*biosynthesis/immunology ; Female ; Dexamethasone/*pharmacology ; Cytokines/*biosynthesis ; Antibodies, Protozoan/*biosynthesis/immunology ; Animals

We investigated the response to challenge infection with Cryptosporidium parvum oocysts in immunosuppressed C57BL/6N mice. In the primary infection, fecal oocyst shedding and parasite colonization were greater in immunosuppressed mice than in nonimmunosuppressed mice. Compared with primary infection, challenge infection with C. parvum didn't show any oocyst shedding and parasite colonization. Especially, oocyst shedding and parasite colonization from the mice infected with heatkilled oocysts were not detected. After challenge infection with C. parvum oocysts, however, these mice were shedding small numbers of oocysts and parasite colonization. Except normal control and uninfected groups, the antibody titers of other groups appear similar. Based on the fecal oocyst shedding, parasite colonization of ilea, and antibody titers in the mice, these results suggest that the resistance to challenge infection with C. parvum in immunosuppressed C57BL/6N mice has increased.
Animals ; Antibodies, Protozoan/blood ; Cryptosporidiosis/*immunology/*parasitology ; Cryptosporidium parvum/*immunology ; Dexamethasone/immunology ; Enzyme-Linked Immunosorbent Assay ; Feces/parasitology ; Female ; Fluorescent Antibody Technique, Indirect ; Histocytochemistry ; Ileum/parasitology ; Immunocompromised Host ; Mice ; Mice, Inbred C57BL ; Oocysts/immunology ; Random Allocation

OBJECTIVETo study the anti-inflammatory effect of the combination of Epimedii Folium, Ligustri Lucidi Fructus and dexamethasone on asthma and its effect in inhibiting adverse reaction against hormone.

METHODDexamethasone had been injected intraperitoneally into asthmatic model rats for 2 weeks, together with the oral administration of Epimedii Folium and Ligustri Lucidi Fructus. The contents of IL-4, INF-gamma, IL-5 and GCR in BALF, serum COR, plasma ACTH and hypothalamic CRH were observed.

RESULTThe combination of Epimedii Folium, Ligustri Lucidi Fructus and dexamethasone can significantly decrease the contents of IL-5 and IL-4 in BALF and ACTH and CRH content in plasma, increase the content of IFN-gamma and GCR in BALF and balance Th1/Th2.

CONCLUSIONThe combination of Epimedii Folium, Ligustri Lucidi Fructus and dexamethasone has a better anti-inflammatory effect on asthmatic model rats, and play a protective role in the pathway of endogenous dexamethasone.

Animals ; Asthma ; drug therapy ; immunology ; Bronchoalveolar Lavage Fluid ; immunology ; Cytokines ; analysis ; Dexamethasone ; administration & dosage ; Drug Therapy, Combination ; Drugs, Chinese Herbal ; administration & dosage ; Ligustrum ; Male ; Rats ; Rats, Sprague-Dawley ; Th1 Cells ; immunology ; Th2 Cells ; immunology

OBJECTIVEEosinophilic airway inflammation is one of the basic characteristics of allergic asthma. Toll-like receptor is one of the most important innate immunity pattern recognition receptors. Glucocorticoids (GCS) are still the most effective treatment for asthma. However, few reports of studies on regulatory mechanism of GCS on the innate immunity system are available. The mechanism of effects of GCS on TLR4 is unclear. The present study aimed at understanding the effect of dexamethasone (DXM) on change of TLR4 and mechanism of regulatory effect of TLR4 on eosinophil (EOS) apoptosis.

METHODSTwenty-seven Sprague-Dawley (SD) rats (age 28 to 42 days, body weight 120 to 180 gram) were randomly divided into the control group, asthma group and DXM group with 9 in each. Asthma model rats were sensitized with the mixture of ovalbumin (OVA, 1 mg) and Al (OH)(3), 100 mg on day 1 and day 8, repeatedly exposed to aerosolized OVA after day 15, once a day for three days and continued for 30 minutes at every time. During the sensitization stage, 100 microg/ml DXM were prepared with DXM group for every other day, and the same doses DXM were prepared for every day on the stage of challenge. The histopathological changes of lung tissues were observed with light microscope (LM). EOS and other inflammatory cells in bronchoalveolar lavage fluid (BALF) were counted; the concentrations of OVA-sIgE in serum were measured by using "sandwich" ELISA; The expressions of TLR4 mRNA were determined by in situ hybridization, the apoptosis of EOS was detected by TUNEL.

RESULTS(1) LM showed many inflammatory cells infiltration around the bronchi and blood vessels, bronchus mucus increased, airway epithelium damage and desquamation, and airway mucous plugs in asthma group, whereas DXM group showed significantly milder changes. (2) Inflammationary cells count in BALF of asthma group was significantly higher as compared to control group (P < 0.01); compared with asthma group, the total cell count, EOS absolute count and EOS% were all significantly decreased in DXM group [(2.14 +/- 0.10) x 10(9)/L, (4.78 +/- 1.23) x 10(7)/L, (2.17 +/- 0.25)%]. (3) Levels of OVA-sIgE in serum of asthma group [(83.40 +/- 6.80) microg/ml] were significantly higher than those of the control group [(14.38 +/- 4.25) microg/ml] (P < 0.01), while those of DXM group [(45.02 +/- 7.47) microg/ml] were significantly lower than asthma group (P < 0.0 1). (4) There were no significant differences in TLR4 mRNA detected by in situ hybridization between control group (24.71 +/- 0.85) and asthma group (25.81 +/- 3.56) (P > 0.05); but it significantly increased in DXM group (29.86 +/- 3.92) as compared to asthma group. (5) The percentages of apoptotic EOS in asthma group [(7.39 +/- 1.93)%] were significantly lower than those in control group [(9.06 +/- 1.52)%] (P < 0.01); and significantly higher in DXM group [(13.33 +/- 1.09)%] than in asthma group (P < 0.01). There were significantly positive correlations between TLR4 mRNA and the percentage of apoptotic EOS (r = 0.612, P < 0.01).

CONCLUSIONDXM can decrease OVA-sIgE level, induce EOS apoptosis, which may correlate with the activation of TLR4 signal transduction.

Animals ; Apoptosis ; Asthma ; chemically induced ; immunology ; Bronchoalveolar Lavage Fluid ; cytology ; Dexamethasone ; pharmacology ; Eosinophils ; immunology ; Glucocorticoids ; pharmacology ; Immunoglobulin E ; blood ; Lung ; pathology ; Ovalbumin ; Rats ; Rats, Sprague-Dawley ; Signal Transduction ; drug effects ; Toll-Like Receptor 4 ; immunology ; metabolism

OBJECTIVETo evaluate the impact of platelet membrane glycoprotein (GP)-specific autoantibodies on high-dose dexamethasone therapy in patients with idiopathic thrombocytopenic purpura (ITP).

METHODSModified direct monoclonal antibody immobilization of platelet antigen assay (MAIPA) was used to detect platelet GPIIb/IIIa and/or GPI b specific autoantibodies. All patients received oral dexamethasone 40 mg/d for 4 days.

RESULTSThe response rate of high-dose dexamethasone in GPIIb/IIIa and/or GPIb specific autoantibody-negative patients was significantly different from that of antibody-positive patients (P<0.05). The response rate of GPIIb/IIIa specific autoantibody-positive patients was lower than that of antibody-negative patients (P<0.05). GPIb specific autoantibody had no significant impact on the efficacy of high-dose dexamethasone (P>0.05).

CONCLUSIONPlatelet membrane GPIIb/IIIa-specific autoantibody can be a potential negative indicator for ITP patients'response to high-dose oral dexamethasone.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Autoantibodies ; blood ; Dexamethasone ; administration & dosage ; therapeutic use ; Female ; Humans ; Male ; Middle Aged ; Platelet Glycoprotein GPIIb-IIIa Complex ; immunology ; Platelet Glycoprotein GPIb-IX Complex ; immunology ; Purpura, Thrombocytopenic, Idiopathic ; drug therapy ; immunology ; Treatment Outcome ; Young Adult

OBJECTIVETo investigate the effects of dexamethasone on Th1/Th2 cytokines in oral lichen planus.

METHODSPeripheral blood mononuclear cells (PBMC) were isolated by density gradient centrifugation from OLP patients and healthy controls. PBMC from patients with OLP were stimulated with phytohemagglutinin (PHA) and dexamethasone respectively for 72 h. The concentrations of interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) in culture supernatants were determined by ELISA. The mRNA levels for IFN-gamma and IL-4 in culture cells were evaluated using semi-quantitative reverse transcription-polymerase chain reaction.

RESULTSCompared with healthy controls, the levels of IFN-gamma in OLP patients were significantly lower (P < 0.05). The levels of IL-4 were higher, but not statistically significant (P > 0.05). The ratios of IFN-gamma/IL-4 were lower in patients with OLP (P < 0.05). Dexamethasone significantly inhibited the levels of IFN-gamma and IL-4 (P < 0.01). Moreover, IFN-gamma was inhibited significantly more than IL-4. The levels of IFN-gamma and IL-4 mRNA expression in culture cells were consistent with protein production in supernatants.

CONCLUSIONSTh2 immune response is predominant in OLP. Dexamethasone is an immunosuppressant inhibiting Th1/Th2 cytokines.

Adult ; Cells, Cultured ; Dexamethasone ; pharmacology ; Female ; Glucocorticoids ; pharmacology ; Humans ; Interferon-gamma ; analysis ; Interleukin-4 ; analysis ; Lichen Planus, Oral ; immunology ; Male ; Middle Aged ; Th1 Cells ; drug effects ; immunology ; Th2 Cells ; drug effects ; immunology

The mechanism underlying T cell-mediated fulminant hepatitis is not fully understood. In this study, we investigated whether myeloid derived suppressor cells (MDSCs) could prevent the concanavalin A (ConA)-induced hepatitis through suppressing T cell proliferation. We observed an increase in the frequencies of MDSCs in mouse spleen and liver at early stage of ConA treatment, implicating that the MDSCs might be involved in the initial resistance of mice against ConA-mediated inflammation. Subpopulation analysis showed that the MDSCs in liver of ConA-induced mice were mainly granulocytic MDSCs. Adoptive transfer of the bone marrow-derived MDSCs into ConA-treated mice showed that the MDSCs migrated into the liver and spleen where they suppressed T cell proliferation through ROS pathway. In addition, the frequencies of MDSCs in mice were also significantly increased by the treatment with immune suppressor glucocorticoids. Transfer of MDSCs into the regulatory T cell (Treg)-depleted mice showed that the protective effect of MDSCs on ConA-induced hepatitis is Treg-independent. In conclusion, our results demonstrate that MDSCs possess a direct protective role in T cell-mediated hepatitis, and increasing the frequency of MDSCs by either adoptive transfer or glucocorticoid treatment represents a potential cell-based therapeutic strategy for the acute inflammatory disease.
Adoptive Transfer ; Animals ; Blotting, Western ; Bone Marrow Cells ; immunology ; CD11b Antigen ; immunology ; metabolism ; Cell Movement ; immunology ; Cell Proliferation ; Chemical and Drug Induced Liver Injury ; etiology ; immunology ; prevention & control ; Concanavalin A ; toxicity ; Dexamethasone ; pharmacology ; Flow Cytometry ; Glucocorticoids ; pharmacology ; Liver ; immunology ; pathology ; Male ; Mice, Inbred C57BL ; Mitogens ; administration & dosage ; toxicity ; Myeloid Cells ; immunology ; metabolism ; transplantation ; Receptors, Chemokine ; immunology ; metabolism ; Spleen ; immunology ; pathology ; T-Lymphocytes ; immunology ; T-Lymphocytes, Regulatory ; immunology

The recent advances in the basic hematology and immunology have significantly enhanced the understanding of histiocytic disorders. The Histiocyte Society which was established in 1985 enabled the randomized trials for these diseases, and important knowledge regarding pathogenesis, clinical presentation, diagnosis, therapy and late consequences has been obtained. The treatment of Langerhans cell histiocytosis (LCH) has varied greatly over last decades, and is still controversial. Therapy can be reduced for low risk patients, and it is possible to discriminate early the non-responding patients with risk disease who might require more intensified treatment. Current therapy of LCH recommended by the Histiocyte Society (LCH-III protocol) is activated in 2001. Hemophaocytic histiocytosis (HLH) is fatal if diagnosis is delayed and appropriate therapy is not instituted rapidly. The diagnostic criteria for HLH is revised by the Histiocyte Society for the current treatment protocol (HLH-2004) which consists of dexamethasone, etoposide, and cyclosporin in combination with intathecal methotrexate. Hematopoietic stem cell transplantation is usually necessary for the primary HLH and recurrent secondary HLH.
Allergy and Immunology ; Clinical Protocols ; Cyclosporine ; Dexamethasone ; Diagnosis ; Etoposide ; Hematology ; Hematopoietic Stem Cell Transplantation ; Histiocytes ; Histiocytosis ; Histiocytosis, Langerhans-Cell ; Humans ; Lymphohistiocytosis, Hemophagocytic ; Methotrexate