OBJECTIVE: To screen anti-tumor drugs that improve antigen processing and presentation in acute myeloid leukemia (AML) cells. METHODS: A TCR-like or TCR mimic antibody that can specifically recognize HLA-A*0201:WT1_126-134 ( RMFPNAPYL) complex (hereafter referred to as HLA-A2:WT1) was synthesized to evaluate the function of antigen processing and presentation machinery (APM) in AML cells. AML cell line THP1 was incubated with increasing concentrations of IFN-γ, hypomethylating agents (HMA), immunomodulatory drugs (IMiD), proteasome inhibitors (PI) and γ-secretase inhibitors (GSI), followed by measuring of HLA-ABC, HLA-A2 and HLA-A2:WT1 levels by flow cytometry at consecutive time points. RESULTS: The TCR-like antibody we generated only binds to HLA-A*0201⁺WT1⁺ cells, indicating the specificity of the antibody. HLA-A2:WT1 level of THP-1 cells detected with the TCR-like antibody was increased significantly after co-incubation with IFN-γ, showing that the HLA-A2:WT1 TCR like antibody could evaluate the function of APM. Among the anti-tumor agents screened in this study, GSI (LY-411575) and HMA (decitabine and azacitidine) could significantly increase the HLA-A2:WT1 level. The IMiD lenalidomide and pomalidomide could aslo upregulate the expression of HLA-A2:WT1 complex under certain concentrations of the drugs and incubation time. As proteasome inhibitors, carfilzomib could significantly decreased the expression of HLA-A2:WT1, while bortezomib had no significant effect on HLA-A2:WT1 expression. CONCLUSION HLA-A2:WT1 TCR-like antibody can effectively reflect the APM function. Some of the anti-tumor drugs can affect the APM function and immunogenicity of tumor cells.
Humans ; Leukemia, Myeloid, Acute/immunology* ; Antineoplastic Agents/pharmacology* ; Antigen Presentation/drug effects* ; HLA-A2 Antigen/immunology* ; Receptors, Antigen, T-Cell/immunology* ; Cell Line, Tumor ; Interferon-gamma

OBJECTIVETo observe the effects of iodine/selenium on the function of antigen presentation of peritoneal macrophages in rats and explore the immunological mechanisms of iodine/ selenium's role in pathogenesis of autoimmune thyroid diseases (AITD).

METHODSFemale Lewis rats were randomly divided into four groups including (1) low selenium and normal iodine group (L(sE)N(I)) (2) low selenium and high iodine group (L(Se)H(I)) (3) normal selenium and normal iodine group (N(Se)N(I) ) (4) normal selenium and high iodine group (N(Se)H(I)). All rats were fed by a special diet with lower selenium and iodine in it and drunk ion-free water containing different levels of iodine and selenium for 3 months. Peritoneal macrophages of each group and OVA allergized T cells were prepared and cultured together. Then the function of antigen presentation were estimated by detecting the levels of IL-2 in the culture supernatant. The levels of the expression of co-stimulator CD86 in the spleen of each group were determined by RT-PCR.

RESULTSThe level of IL-2 in the supernatant in N(Se)H(I) (43.22 +/- 3.27) pg/ml was much stronger than N(Se)N(I) [the level of IL-2 was (25.74 +/- 2.45) pg/ml, P < 0.05]. The level of IL-2 in L(Se)N(I) (15.79 +/- 2.13) pg/ml was significantly lower than N(Se)N(I) (P < 0.05). The expression of CD86 mRNA in N(Se)H(I) (CD86/beta-actin: 0.52 +/- 0.10) were higher than N(Se)N(I) (CD86/beta-actin: 0.35 +/- 0.04), P < 0.05.

CONCLUSIONSHigh iodine could promote the presentation function of macrophages to a higher state than normal. Therefore, high iodine intake might become an importantly inducing factor in thyroid autoimmunity. Low selenium could weaken the ability of recognizing and presenting OVA antigen of peritoneal macrophages which might destroy immunological homeostasis and thus the low selenium intake might also become an inducer of AITD.

Animals ; Antigen Presentation ; drug effects ; immunology ; Female ; Iodine ; pharmacology ; Macrophages, Peritoneal ; drug effects ; immunology ; Rats ; Rats, Inbred Lew ; Selenium ; pharmacology

OBJECTIVETo investigate the ability of human dendritic cells (DCs) inducing specific T lymphocyte response and inhibit the expression of HBeAg and HBsAg in 2.2.15 cell culture supernatant.

METHODSDCs were prepared from peripheral blood mononuclear cells induced with granulocyte macrophage colony-stimulating factor(GM-CSF) and interleukin 4. DCs was impulsed with pure HBsAg before DCs maturation and cocultured with self-blood T lymphocyte, while DCs without pure HBsAg stimulated group, T lymphocyte group and only T lymphocyte group were prepared as control group. The culture supernatant of 2.2.15 cell with stimulated T lymphocytes was collected on day 1, day 3, day 5 and day 7, respectively. The expressed levels of HBeAg and HBsAg were detected by ELISA method.

RESULTSDCs after antigen stimulation had a strong ability to present antigen and induce immune activation, DCs after loading with antigen in normal control and chronic hepatitis patients group had stronger stimulative ability for T lymphocytes proliferation than that of DCs without loading with antigen and only T lymphocyte group(P less than 0.01). The stimulating ability of DCs had a positive correlation to the dosage of loaded antigen; CTLs produced as a result of DCs stimulation had a specific inhibitive effect on the expression of HBeAg in 2.2.15 cell supernatant,but not on the expression of HbsAg.

CONCLUSIONHuman dendritic cells stimulated with HBsAg in vitro can efficiently present antigen and stimulate the production of specific CTLs to HBV, which can efficiently inhibit the expression of HBeAg in 2.2.15 cell supernatant- DC vaccine may become an antiviral therapy strategy for chronic hepatitis B virus infected patients in future.

Adolescent ; Adult ; Antigen Presentation ; Cells, Cultured ; Child ; Dendritic Cells ; drug effects ; immunology ; Female ; Hepatitis B Surface Antigens ; pharmacology ; Hepatitis B, Chronic ; immunology ; Humans ; Lymphocyte Activation ; Male ; Middle Aged