فهرست مطالب zahra gheflati

Allergic rhinitis (AR) is an inflammatory disorder of the nasal mucosa with high morbidity and prevalence. Natural killer (NK) cells might have a role in AR. We aimed to evaluate the changes of the markers and receptors on NK cells in AR patients compared to the non-atopic controls. Flow cytometric analysis was used with double staining of the Peripheral Blood Mononuclear Cells (PBMCs) to examine the expression of CD25 and CD69 markers, and NKG2D and NKG2A receptors on NK cells of 20 patients with AR and 20 non-atopic controls. The serum total IgE level was measured by Enzyme-linked Immunosorbent Assay. The expression of CD69 antigen on NK cells in AR patients was significantly higher than that of healthy group (p=0.03). No significant changes were observed between CD25, NKG2D and NKG2A expression on the surface of NK cells from healthy and AR subjects. Our study also showed that there was no significant correlation between the expression of CD69, CD25, NKG2D and NKG2A and level of serum total IgE in AR patients and normal subjects. These results indicated that the expression of CD69 antigen on NK cells of AR patients was increased. The high expression of CD69 on NK cells in AR patients suggested that these cells were activated, probably due to the cytokines secreted from allergen-stimulated T cells and activated monocytes.

Using dendritic cells (DCs) loaded with tumor antigens as a therapeutic strategy against tumors has been proposed. In order to increase the efficacy of DCs، a variety of factors such as TLR ligand molecules and bacterial products are used. In this study، the protein components of the bacteria Listeria monocytogeneses (LM) for induction of dendritic cell maturation were used. Bone marrow cells of Balb/c mice in the presence of IL-4 and GM-CSF were cultured for 5 days. On day 5، tumor lysate and then protein components or total extract of LM was added to immature DCs. In order to survey the maturation status of DCs، on day 7، the expression of CD80، CD86 AND MHC-II on the cell surface was evaluated. After induction of tumors in mice using WEHI-164 cell line، 106 mature dendritic cells subcutaneously injected. Tumor growth rate، survival rate and cytotoxic activity of spleen cells were evaluated in the studied groups. In mice vaccinated with protein components matured-DCs، delayed tumor growth rate and increased survival were seen. In addition، in these mice، the cytotoxic activity of spleen cells was higher compared to other groups. In all groups receiving protein components or total extract mature-DCs، increased cytotoxic activity and decreased tumor growth rate were seen compared to controls. Listeria monocytogenes protein components compared to total extract have higher ability to increase the efficacy of DCs for tumor immunotherapy in mouse model.

The use of dendritic cells (DCs) as a cellular adjuvant provides a promising approach in immunotherapy of cancer. It has been demonstrated that Listeria monocytogenes activated DCs pulsed ex vivo with tumor antigens trigger a systemic Th1-biased specific immune response and a single dose of this vaccine will cause a considerable anti tumor immunity. The present study was designed to evaluate the ability of multiple doses of tumor antigen-pulsed DCs, matured in the presence of Listeria monocytogenes components in induction of a potent anti-tumor response and the prevention of tumor formation in an experimental model. Bone-marrow derived DCs (BMDCs) were cultured in the presence of GM-CSF and IL-4. After 5 days, tumor lysates with/without Listeria monocytogenes lysate were added to the culture media for another 2 days. Mice received mature and tumor antigen pulsed dendritic cells subcutaneously in 3 groups. Tumor growth was monitored and two weeks after immunotherapy, cytotoxic activity of CD8+ T cells was evaluated in different groups. According to the findings, repeated doses of vaccine did not lead to a significant increase in the activity of cytotoxic T cells and decreased tumor growth of immunized animals. The current study suggests that increased doses of vaccine do not have sufficient efficiency for prevention of tumor induction. Generation of T regulatory responses upon repeated doses of such vaccines should be considered in future investigations.

Apart from genetic and environmental factors, activation of autoreactive mechanisms has been proposed to play a role in the pathogenesis of schizophrenia. In re-cent years, considerable work has been carried out to understand the role and contribution of the immune system in this disease. To investigate the T cell response to phytohaemagglutinin (PHA) and determine the serum levels of anti-nuclear antibody (ANA), anti-cytoplasmic antibody (ACA), and circulating immune complexes (CIC) in schizophrenic patients. A total of 30 drug-free schizophrenic patients and 42 healthy controls were enrolled in this study. T cell proliferation in response to PHA was measured using Methyl Thiazol Tetrazolium test. ANA and ACA were measured by indi-rect immunofluorescence. CIC concentration was determined using poly ethylene glycol precipitation assay. Mean PHA response was 1.96 ± 0.83 in patients and 3.72±1.39 in healthy controls (p < 0.001). ANA and CIC concentrations were not signifi-cantly different between two groups. In addition, ACA was detected only in patients. Increased production of ACA together with lower T cell response to mito-gens in our patients provides evidence for the involvement of autoimmune mechanisms in the pathogenesis of schizophrenia.

Bacterial DNA has immunostimulatory effects on different types of immune cells such as dendritic cells (DCs). Application of DCs as a cellular adjuvant represents a promising approach in the immunotherapy of infectious disease and cancers. To investigate the effect of tumor antigen pulsed DCs in the presence of CpG-1826 in treatment of a murine model of cancer. WEHI-164 cells (Balb/c derived fibrosarcoma cell line) were injected subcutaneously in the right flank of mice. Bone marrow cells were cultured in the presence of GM-CSF and IL- 4. After 5 days, tumor lysate, CpG-1826, and oligodeoxynucleosides, as control, were added to the culture media and incubated for 2 days. Cytokine production in DCs culture media was measured by ELISA. Then DCs were injected subcutaneously around the tumor site in the right flank of mice. Tumor growth rate was monitored in case and control groups. Two weeks after DCs immunotherapy, cytotoxic assay was conducted using various amounts of effector (splenic T cells) and target cells (WEHI-164 or CT26) for 6 h. Immunotherapy with DCs treated withCpG led to a significant increase in the activity of cytotoxic T cells and decreased tumor growth in immunized mice. In the control group which received DCs without CpG treatment, no change in cytotoxic activity and tumor growth rate was detected. The current study suggests that specific anti tumor immune responses can be induced by DCs matured with CpG and proposes CpG usage in DCs targeted clinical strategies.