Wenjie Zhang; Shan Liu; Lin Zhao; Juncheng Wang; Meng Liu; Fengge Wang; Yuekang Xu
Abstract
Background: The functions of dendritic cells (DCs) are influenced by their intracellular metabolism, in which liver kinase B1 (LKB1) plays an important role. However, due to the difficulty in isolating the DCs, the roles of LKB1 in DC maturation and functions in tumor settings have been poorly characterized.Objective: ...
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Background: The functions of dendritic cells (DCs) are influenced by their intracellular metabolism, in which liver kinase B1 (LKB1) plays an important role. However, due to the difficulty in isolating the DCs, the roles of LKB1 in DC maturation and functions in tumor settings have been poorly characterized.Objective: To investigate the roles of LKB1 in DC functions including phagocytosis and presentation of antigens, activation, T cell differentiation, and ultimately tumor eradication.Methods: Genetic modification of Lkb1 in the DCs was made by lentiviral transduction, and their impacts on T cell proliferation, differentiation, activity, or B16 melanoma metastasis were examined by flow cytometry, qPCR, or lung tumor nodule counting.Results: LKB1 did not affect antigen uptake and presentation by the DCs, but facilitated the stimulation of T cell proliferation. Interestingly, following T cell activation, Foxp3-expressing regulatory T cells (Treg) were increased (P=0.0267) or decreased (P=0.0195) in mice injected with Lkb1 knockdown DCs or overexpressing DCs, respectively. Further exploration revealed that LKB1 inhibited OX40L (P=0.0385) and CD86 (P=0.0111) expression, and these co-stimulatory molecules enhanced Treg proliferation, and downregulated immune suppressive cytokine IL-10 (P=0.0315). Moreover, we found that the injection of the DCs with limited LKB1 expression before tumor inoculation could reduce their production of granzyme B (P<0.0001) and perforin (P=0.0042) from CD8+T cells, thereby impairing their cytotoxicity and promoting tumor growth.Conclusion: Our data suggest that LKB1 can enhance DC-mediated T cell immunity by restraining Treg development and thereby suppressing tumor growth.
Yaghoub Mollaei-Kandelous; Pedram Ahmadpoor; Mohsen Nafar; Mohammad Reza Khatami; Samad Farashi Bonab; Nader Tajik; Mahdi Shekarabi; Aliakbar Amirzargar
Abstract
Background: Impaired renal function is considered as a significant risk factor for cardiovascular events in chronic kidney disease patients. Several immunosuppressive drugs are used in these patients, which necessitates to minimize the drug-related side effects by employing alternative strategies.Objective: ...
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Background: Impaired renal function is considered as a significant risk factor for cardiovascular events in chronic kidney disease patients. Several immunosuppressive drugs are used in these patients, which necessitates to minimize the drug-related side effects by employing alternative strategies.Objective: This study aimed to evaluate prospectively the influence of low dose ATG induction therapy with two different protocols (Sirolimus versus Mycophenolate mofetil) on the expression of functional markers (LAG-3, CD39, and intracellular CTLA-4) on conventional Tregs in renal recipients.Methods: Thirty-eight renal transplant recipients were enrolled in this study. The patients were randomly assigned into two groups, including TMP: Tacrolimus (Tac), Mycophenolate mofetil (MMF), and Prednisolone (n=23); and TSP: Tac, Sirolimus (SRL), and Prednisolone (n=15). The frequency of LAG-3, CD39, and intracellular CTLA-4 on circulating Tregs was analyzed by flow cytometry before and after transplantation.Results: Analysis of the flow cytometry data showed that the frequency of CD4+CD25+FOXP3+ Tregs increased 4 months post-transplantation compared to pre-transplantation in both groups, although this increase was only significant in TMP group. In TMP treated patients, the frequency of LAG-3+ Tregs and CD39+ Tregs increased, whereas the frequency of intracellular CTLA-4+ Tregs decreased 4 months post-transplantation. In TSP group, while the frequency of CD39+ Tregs increased, the frequency of CTLA-4+ Tregs decreased in post-transplantation compared to pre-transplantation.Conclusions: it seems that both treatment regimen protocols with a low dose ATG induction therapy may be clinically applicable in kidney transplant recipients.
Azam Jamshidian; Mohammad Kazemi; Vahid Shaygannejad; Mansoor Salehi
Volume 12, Issue 4 , December 2015, , Pages 311-318
Abstract
Background: Lack of sufficient information on the mechanism of plasma exchange (PE) therapy in multiple sclerosis (MS), has limited this treatment to individual patients with severe relapses who have been refractory to other treatments. This is while PE is used very successfully as a first-line standard ...
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Background: Lack of sufficient information on the mechanism of plasma exchange (PE) therapy in multiple sclerosis (MS), has limited this treatment to individual patients with severe relapses who have been refractory to other treatments. This is while PE is used very successfully as a first-line standard treatment in many other neuro-immune disorders. Recent data suggest that Treg/Th17 counterbalance may indicate the boundaries between promotion and regulation of inflammatory responses in MS and Treg/Th17 ratio may be useful as a marker for monitoring the efficiency of MS therapies. Objective: To evaluate the effect of PE on the frequency and ratio of Treg/Th17 cells through concomitant measurement of the expression levels of Treg and Th17 lineage specific transcription factors, FOXP3 and RORC2, respectively. Methods: Peripheral blood mononuclear cells of 8 relapsed MS patients were obtained before and after a complete course of PE therapy and the FOXP3 and RORC2 mRNA levels were assayed using real-time PCR approach. Results: No significant change in the expression levels of individual transcription factors existed, but a significant increase in FOXP3/RORC2 ratio (p=0.036) was observed. Conclusions: Our results suggest that PE therapy influences Treg/Th17 ratio and this maybe a mechanism by which this procedure exerts its improving effects in MS disease.
Nasrollah Erfani; Mahboobeh Hamedi-Shahraki; Somayeh Rezaeifard; Mohammadreza Haghshenas; Manoochehr Rasouli; Alamtaj Samsami Dehaghani
Volume 11, Issue 2 , June 2014, , Pages 105-112
Abstract
Background: Ovarian cancer is the fifth leading cause of death from malignancy in women. CD4 +CD25+FoxP3+ regulatory T (Treg) cells are a subset of T lymphocytes with great inhibitory impact on immune response. Objectives: To investigate the percentage of CD4 +CD25+FoxP3+ regulatory T cells in the peripheral ...
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Background: Ovarian cancer is the fifth leading cause of death from malignancy in women. CD4 +CD25+FoxP3+ regulatory T (Treg) cells are a subset of T lymphocytes with great inhibitory impact on immune response. Objectives: To investigate the percentage of CD4 +CD25+FoxP3+ regulatory T cells in the peripheral blood of the Iranian patients with epithelial ovarian cancer compared to healthy women and to evaluate the correlation of the Treg cell percentage with clinicopathological characteristics including cancer stage and CA-125 serum level. Methods: Seventeen women with epithelial ovarian cancer and 20 healthy subjects were enrolled in the study. Peripheral blood mononuclear cells were stained at the surface, for CD4 and CD25 molecules, followed by fixation, permeabilization and intracellular staining for FoxP3 molecule. After processing and flowcytometry analysis, prevalence of Treg cells was determined as the percentages of CD25 +FoxP3+ cells among CD4+ lymphocytes. Results: Despite no difference in the percentage of total CD4+ lymphocytes, analysis indicated that Treg cell percentage was significantly higher in ovarian cancer patients than controls (5.7 ± 3.1% versus 2.8 ± 1.4%, p=0.002). A trend toward higher Treg cells was observed in higher stages of ovarian cancer (III+IV) in comparison to lower stages (I+II) (6.5 ± 3.2% vs. 4.44 ± 2.7%, p=0.2). Higher percentage of Treg cells was also observed in the patients with high CA125 (CA-125 >100 U/mL) in comparison to those with low CA-125 serum level (CA-125 ≤100 U/mL) although the difference was not significant (6.44 versus 4.18%, p=0.19). Conclusion: Increased frequency of Tregs in ovarian cancer might participate in immune suppression in these patients. The findings collectively suggest the likely impact of Treg cell–targeted immunotherapy in ovarian cancer.
