Extracting Mutual Interaction Rules Using Fuzzy Structured Agent-based Model of Tumor-Immune System Interactions.

BACKGROUND: There are many studies to investigate the effects of each interacting component of tumor-immune system interactions. In all these studies, the distinct effect of each component was investigated. As the interaction of tumor-immune system has feedback and is complex, the alternation of each component may affect other components indirectly. OBJECTIVE: Because of the complexities of tumor-immune system interactions, it is important to determine the mutual behavior of such components. We need a careful observation to extract these mutual interactions. Achieving these observations using experiments is costly and time-consuming. MATERIAL AND METHODS: In this experimental and based on mathematical modeling study, to achieve these observations, we presented a fuzzy structured agent-based model of tumor-immune system interactions. In this study, we consider the confronting of the effector cells of the adaptive immune system in the presence of the cytokines of interleukin-2 (IL-2) and transforming growth factor-beta (TGF-ß) as a fuzzy structured model. Using the experimental data of murine models of B16F10 cell line of melanoma cancer cells, we optimized the parameters of the model. RESULTS: Using the output of this model, we determined the rules which could occur. As we optimized the parameters of the model using escape state of the tumor and then the rules which we obtained, are the rules of tumor escape. CONCLUSION: The results showed that using fuzzy structured agent-based model, we are able to show different output of the tumor-immune system interactions, which are caused by the stochastic behavior of each cell. But different output of the model just follow the predetermined behavior, and using this behavior, we can achieve the rules of interactions.

Stable silencing of IGF1R using Lentiviral-mediated shRNA in HEK293T cells.

Insulin-like growth factors are among the peptide mitogens that regulate cell proliferation and differentiation as well as mediator of antiapoptotic signals. The imbalance between the expression and activities of these molecules may lead to malignancy in cells. Evidences have suggested the insulin-like growth factor 1 receptor (IGF-1R) signaling pathway as a therapeutic target in the management and treatment of cancer. In this present study, we have generated silencing stable clones of HEK cells using six different pGIPZ (lentiviral vector) shRNAs targeted to human IGF-1R gene and a pGIPZ non-silencing shRNAmir lentiviral vector (as negative control). The recombinant lentiviral vectors were separately transduced into human embryonic kidney 293 T (HEK293T) cell lines. The knockdown of IGF-1R was confirmed by reverse transcription polymerase chain reaction (RT-PCR) and the relative IGF-1R mRNA levels were expressed as a ratio of IGF-1R to ß-actin by REST software. The results showed significant reduction in the expression of IGF-1R mRNAs in cells transduced with all six pGIPZ-IGF-1R recombinant lentivirals compared to non-silencing negative control. No significant difference was observed among the six cassettes. Results indicated that recombinant lentiviral vectors provided an efficient and stable knockdown of IGF-1R providing useful tool for IGF-1R pathway studies.

PiggyBac as a novel vector in cancer gene therapy: current perspective.

Selection of suitable delivery system is one of the crucial aspects in gene therapy that determines the efficiency of gene therapy. The past two decades have witnessed extensive efforts for finding safe and efficient vectors to overcome the limitations of viral vectors. The utilization of DNA transposon-based vectors for gene therapy has emerged as a promising non-viral alternative. DNA 'cut-and-paste' is one of the main mechanisms of genome engineering by transposon elements. However, the lack of an efficient transposition system has limited the utilization of transposon vectors in mice and mammalian systems. PiggyBac (PB) is known as a highly efficient DNA transposon originally isolated from Trichoplusia ni as an alternative to Sleeping Beauty (SB). It has been shown that PB can be functional in various species including mammalian systems. This vector could overcome some limitations of other vectors in cancer gene therapy. Some advantages of PB include the capacity for integration into the genome and providing a stable expression, capacity to harbor 10 and 9.1 kb of foreign DNA into the host genome, without a significant reduction in their transposition activity and display non-overlapping targeting preferences. However, to advance PB to clinical applications, some obstacles still require to be overcome to improve its safety and efficiency. Hence, it seems that this vector could open new horizons in gene and cancer therapy.

Tumour regression induced by co-administration of MIP-3α and CpG in an experimental model of colon carcinoma.

CCL20/macrophage inflammatory protein-3α (MIP-3α) represents one of the potent chemoattractive proteins for dendritic cells (DCs). Herein, we investigated whether in vivo genetic modification of tumour cells aimed at intratumoural production of MIP-3α might lead to accumulation of DCs in tumour tissue. Mice injected with CT26, received recombinant adenovirus (Ad) vectors (AdMIP-3α) expressing MIP-3α protein. This was complemented by injections of CpG. Interestingly, MIP-3α gene therapy combined with CpG injections resulted in specific cytotoxicity. This was associated with significant suppression of tumour growth rate. These findings demonstrate the potential of strategies that utilize in vivo overexpression of chemokines.

Methadone ameliorates multiple-low-dose streptozotocin-induced type 1 diabetes in mice.

Type 1 diabetes is an autoimmune disease characterized by inflammation of pancreatic islets and destruction of beta cells by the immune system. Opioids have been shown to modulate a number of immune functions, including T helper 1 (Th1) and T helper 2 (Th2) cytokines. The immunosuppressive effect of long-term administration of opioids has been demonstrated both in animal models and humans. The aim of this study was to determine the effect of methadone, a mu-opioid receptor agonist, on type 1 diabetes. Administration of multiple low doses of streptozotocin (STZ) (MLDS) (40 mg/kg intraperitoneally for 5 consecutive days) to mice resulted in autoimmune diabetes. Mice were treated with methadone (10 mg/kg/day subcutaneously) for 24 days. Blood glucose, insulin and pancreatic cytokine levels were measured. Chronic methadone treatment significantly reduced hyperglycemia and incidence of diabetes, and restored pancreatic insulin secretion in the MLDS model. The protective effect of methadone can be overcome by pretreatment with naltrexone, an opioid receptor antagonist. Also, methadone treatment decreased the proinflammatory Th1 cytokines [interleukin (IL)-1beta, tumor necrosis factor-alpha and interferon-gamma] and increased anti-inflammatory Th2 cytokines (IL-4 and IL-10). Histopathological observations indicated that STZ-mediated destruction of beta cells was attenuated by methadone treatment. It seems that methadone as an opioid agonist may have a protective effect against destruction of beta cells and insulitis in the MLDS model of type 1 diabetes.

Analysis of class-switched memory B cells in patients with common variable immunodeficiency and its clinical implications.

BACKGROUND: Common variable immunodeficiency (CVID) comprises a heterogeneous group of primary immunodeficiency disorders characterized by hypogammaglobulinemia leading to recurrent infections. Some patients with CVID are more susceptible to earlier onset of respiratory disease and bronchiectasis. It has been suggested that memory B cells, characterized by CD27 expression, can be used as a means to classify subsets of CVID patients. OBJECTIVE: The aim of this study was to classify a sample of Iranian patients with CVID by quantification of peripheral blood memory B cells and immature B cells and to assess the relationship between this classification and the clinical characteristics of the patients. METHODS: The study included 29 patients with CVID and 20 healthy controls. Patients were grouped as follows, according to the quantification of peripheral memory B cells: group I had less than 0.4% switched memory B cells (CD27+, immunoglobulin [Ig] M-, IgD-) in peripheral blood lymphocytes (PBL), while in group II switched memory B cells represented more than 0.4% of PBL. Group I patients were further subdivided into groups Ia and Ib according to the proportion of CD21- peripheral B cells. The clinical and laboratory findings for the patients were then compared among the 3 groups. RESULTS: The percentage of switched memory B cells (CD27+IgM-IgD- cells in peripheral B lymphocytes) was markedly reduced in CVID patients compared with controls (P < .001). This percentage was less than 0.4% (group I) in 20 patients (69%) (P < .05). In the remaining 9 patients (group II) and all healthy controls, the percentage was greater than 0.4%. Bronchiectasis was more frequent in group I than group II (P < .05). Following subdivision of group I patients into groups Ia and Ib based on CD21 peripheral B cells, the rate of autoimmunity was found to be much higher in group Ia than group Ib. CONCLUSIONS: CVID patients with reduced numbers of switched memory B cells are more prone to recurrent respiratory infections and development of bronchiectasis, and as such, need more special care than other CVID patients. Thus, classification of CVID patients by assessment of switched memory B cells could help physicians to predict clinical prognosis of these patients.

Altered dendritic cell function in response to sera of common variable immunodeficiency patients.

OBJECTIVE: CVID is characterized by hypogammaglobulinemia and T cell disorder in most cases. Dendritic cells might be severely perturbed in differentiation and maturation but it is not clear whether this perturbation is intrinsic or because of alterations in microenvironmental factors. We evaluated the effects of CVID patient's sera as a source of microenvironmental factors on monocyte-derived DCs (MDCs). METHODS: Monocyte derived DCs (MDCs) were generated in the presence of GM-CSF, IL-4 and 10% concentration of CVID (n = 10) and healthy control (n = 8) serum samples. MDCs were matured with monocyte conditioned medium and TNF-alpha. Mature MDCs were used for: (i) immunophenotyping, (ii) MLR, (iii) co-culture with allogeneic lymphocytes for cytokine production assays and (iv) DC-cytokine production assays after stimulation with CD40L. RESULTS: Treatment of MDCs with sera derived from CVID patients as compared to control sera: (i) causes lower surface expression of HLA-DR after maturation, (ii) leads to production of higher amounts IL-18 by activated MDCs and, (iii) results in lower allostimulatory capacity of MDCs in MLR assays. CONCLUSIONS: Our findings argue for constitutive presence/absence of soluble factors e. g. cytokines in CVID patients' sera steering the immune response toward the cellular rather than the humoral arm. Our observations deserve further studies to identify these factors.

Effects of cured dentin bonding materials on human monocyte viability.

OBJECTIVES: Dentin Bonding Agents (DBAs) have been proposed as root-end filling materials. This study examined the effect of polymerized DBAs on human monocyte viability. STUDY DESIGN: Monocytes were directly isolated from peripheral blood and being exposed to cured Scotch bond I (Single Bond) and Prime & Bond in different time intervals (36 and 72 hours). The viability of monocytes was determined by MTT assay. RESULTS: Viability of the cells was time dependent. There was no significant difference between the effect of 2 DBAs on monocytes. CONCLUSION: Results indicate that DBAs in polymerized form can alter the viability of monocytes and decrease it within time.