Marzieh Holakuyee; Mohammad Hossein Yadegari; Zuhair Mohammad Hassan; Mansour Bayat; Ariyo Shahin Jafari; Mohsen Abolhassani; Abbas Ali Amini; Mehdi Mahdavi
Volume 7, Issue 3 , September 2010, , Pages 142-149
Abstract
Background: Candida albicans is one of the most important opportunistic pathogens that suppress immunologic mechanisms of the host. It is speculated that structural and secretory proteins of C. albicans have immunomodulatory effects in cancer. Objective: To evaluate the effects of C. albicans structural ...
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Background: Candida albicans is one of the most important opportunistic pathogens that suppress immunologic mechanisms of the host. It is speculated that structural and secretory proteins of C. albicans have immunomodulatory effects in cancer. Objective: To evaluate the effects of C. albicans structural and secreted proteins on intratumoral CD4/CD8 ratio as well as the survival rate in BALB/c tumor model. Methods: Structural and secretory proteins from C. albicans were isolated and examined for their effects on tumor growth and survival of adenocarcinoma bearing mice. Results: The results indicated that in mice treated with C. albicans structural protein, the survival rate significantly decreased compared with the control groups. Also, mice treated with secretory proteins showed a decrease in survival rate but it was not statistically significant (p>0.05). Investigating the frequency of tumor infiltrated CD4+ and CD8+ T lymphocytes indicated that the percentages of tumor infiltrated CD4+ T lymphocytes in response to structural and secreted proteins were higher compared to the control groups. Conclusion: Our study suggests that C. albicans structural and secreted proteins modulate intratumor T lymphocyte infiltration.
Bahram Bagherpour; Marjan Gharagozloo; Behjat Moayedi
Volume 6, Issue 1 , March 2009, , Pages 33-39
Abstract
Background: Iron is an essential trace element in cell proliferation. Several investigations demonstrate that iron deprivation inhibits cell proliferation. However, the impact of iron on telomerase activity of activated lymphocytes remains unexplained to date. Objective: In this study, the effect of ...
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Background: Iron is an essential trace element in cell proliferation. Several investigations demonstrate that iron deprivation inhibits cell proliferation. However, the impact of iron on telomerase activity of activated lymphocytes remains unexplained to date. Objective: In this study, the effect of iron on the proliferation and telomerase activity of lymphocytes stimulated by phytohemagglutinin (PHA) were investigated. Methods: Iron loading was performed by incubating peripheral blood mononuclear cells in 500μM FeSO4.7H2O for 24 h and iron chelation was done by exposing cells to desferrioxamine, a potent iron chelator. The effects of silymarin, a flavonoid with both antioxidant and iron chelating activities, on the proliferation and telomerase activity of PHAactivated lymphocytes were also compared with desferrioxamine. Proliferation and telomerase activity were assessed using BrdU incorporation assay and Telomeric Repeat Amplification Protocol (TRAP), respectively. Results: The proliferations of lymphocytes were significantly inhibited by 10 and 20 μg/ml desferrioxamine in a dose dependent manner, while iron loading recovered suppressed cell proliferation to the normal level. Silymarin at 20 μg/ml significantly increased the proliferation of lymphocytes in both normal and iron-treated conditions. Telomerase activity of lymphocytes was markedly increased by iron treatment and suppressed by desferrioxamine. Conversely, iron treatment had no effect on the telomerase activity of lymphocytes incubated with silymarin. Conclusion: Iron plays a significant role in the proliferation and telomerase activity of lymphocytes. The effects of silymarin on the proliferation and telomerase activity of lymphocytes were completely different from those of desferrioxamine, suggesting that the immunomodulatory effect of silymarin is probably not associated with its iron chelating activity.
Abolhassan Faramarzi; Azra Shamsdin; Abbas Ghaderi
Volume 3, Issue 4 , December 2006, , Pages 187-191
Abstract
Background: Tonsils and adenoids are involved in both local immunity and immune surveillance for the development of immune defense mechanisms. A number of investigators have found decreased immunoglobulin levels after adenotonsillectomy while others have failed to find significant changes. The effects ...
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Background: Tonsils and adenoids are involved in both local immunity and immune surveillance for the development of immune defense mechanisms. A number of investigators have found decreased immunoglobulin levels after adenotonsillectomy while others have failed to find significant changes. The effects of adenotonsillectomy on the cellular immunity of children have not been investigated extensively. Objective: To observe the change in humeral and cellular immune systems before and after operation in patients undergoing adenotonsillectomy. Methods: The study comprised 102 patients; all of the patients underwent adenotonsillectomy. The levels of IgG, IgA, and IgM were measured for humoral immunity and the percent of CD7 and CD19 positive cells were determined in blood samples taken from these patients 24 hours before operation and also 2 and 8 weeks after the operation. The results were subjected to statistical analysis. Results: The present study shows that the serum level of IgA would rise few weeks after the operation. Changes in the IgM and IgG level were not statistically significant postoperatively. In addition, no significant change was detected in B lymphocyte count before and after adenotonsillectomy. In our study, there was a slight decrease in the T lymphocyte count in the early stage of post operation, which returned to normal preoperative value after 8 weeks . Conclusion: Several immune system parameters maintain its normal status several weeks after adenotonsillectomy.
Ziba Ghasemi; Babak Farrokhi; Farah Miraghasi; Ardalan Ejaz Ahmad; Nariman Mosaffa
Volume 3, Issue 3 , September 2006, , Pages 121-126
Abstract
Background: Polysaccharides have long been used as immune-modulators in various pathologic conditions including inflammation and solid malignancies. Objective: To evaluate the effects of Zymosan and Betaglucan on cytotoxic reactions in an effectortarget conjugate system. Methods: Blood was obtained from ...
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Background: Polysaccharides have long been used as immune-modulators in various pathologic conditions including inflammation and solid malignancies. Objective: To evaluate the effects of Zymosan and Betaglucan on cytotoxic reactions in an effectortarget conjugate system. Methods: Blood was obtained from 20 healthy subjects; purified mononuclear leukocytes (monocytes and lymphocytes) were extracted and cultured as effector cells by a cytotoxic method. Both adherent and non-adherent cells interacted with the K562 myeloid cell line. The effector-target (E:T) ratio was 1:1, 1:10, and 1:20. To evaluate stimulatory effects of Betaglucan and Zymosan on cytotoxic reactions, samples were divided into case and control groups based on the presence or absence of Betaglucan and Zymosan. MTT assay and sFas ligand (sFasL) concentrations were used to assess the increased killing capacity of effector cells. Results: Our results revealed that Zymosan and Betaglucan can induce cytotoxic responses in macrophages and lymphocytes (P<0.05). The best result was achieved with E:T ratio of 1:1. Both macrophages and lymphocytes produced sFasL following stimulation by Zymosan and Betaglucan, however, the level of production was not statistically significant (P>0.05). Conclusion: Zymosan and Betaglucan can be used as enhancers of the killing capacity of the immune cells; therefore, Betaglucan and Zymosan can be applied as systemic stimulators of the immune response in inflammation and chronic infection.
Akbar Vahdati; Minoo Adib; Shirin Kashfi; Taji Afrooz; Edna Abkar
Volume 2, Issue 4 , December 2005, , Pages 208-212
Abstract
Background: Erythropoietin (EPO) was first known as a factor for red blood cell proliferation and differentiation. New studies show the effects of EPO on immune system. Objective: In this study, the effects of pretreatment with recombinant human erythropoietin (rHuEPO) on the anti-human leukocyte antibody ...
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Background: Erythropoietin (EPO) was first known as a factor for red blood cell proliferation and differentiation. New studies show the effects of EPO on immune system. Objective: In this study, the effects of pretreatment with recombinant human erythropoietin (rHuEPO) on the anti-human leukocyte antibody (anti-HLA) titer were determined. Methods: Three groups of rats were sensitized with human lymphocytes. Two of the groups were given 20 or 100 IU/Kg rHuEPO after two sensitizations with human lymphocytes. Control group did not receive rHuEPO. Microlymphocytotoxicity method was used to detect anti-HLA antibodies. Results: Treatment with rHuEPO caused a significant decline in anti-HLA antibody titer compared to control group. Also, pretreatment with rHuEPO suppressed antibody response after repeated antigenic stimulation. Conclusion: Such results could be due to the effects of rHuEPO on the number or the activity of the B and the T cells. Moreover, the dose of rHuEPO and the length of treatment might affect anti-HLA antibody titer.
