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The paper describes a predictive mathematical model capable of taking into account the complex multicomponent process of interaction of the immune system elements in the event of the appearance of abnormal cells caused by a violation of its synthetic function. The importance of the mathematical simulation application is conditioned by the fact that existing statistical methods do not allow one to fully estimate the effects caused by the functional disorders' accumulation process in the body systems due to the limitations on the development and experimentations. The model has been developed within the concept of the multi-level model of the human organism and is targeted to describe the different-scale processes occurring during the development of cancer. Modelling takes into account the functional state of the studied organs. The factors, having impact on the state changes, natural aging and the negative effects of diverse chemicals entering from the environment can be distinguished. Building on the created interaction scheme, the ordinary differential equations are written, which are described by the First Order ODE's with lags of the argument. To solve the obtained Cauchy Problem, the implicit numerical 3rd order Runge-Kutta Method is used. A number of computational experiments on tumor growth have been performed. The constructed model makes it possible to show the mechanics of the multicomponent interaction of the immune system during the emergence and growth of malignant tumors under the influence of the environment. [ABSTRACT FROM AUTHOR]

Breast cancer arises when cells develop uncontrollably in the breast to form tumour cells. The risk of having breast cancer rises as a woman continues to age. Thus, details about the early stages of cancer progression can help a woman make early treatment choices, preventing them from being diagnosed with these harmful cancers. It is believed that cytotoxic T lymphocytes (CTLs) act as effector cells to eradicate cancer cells. CTLs and tumor cells were discovered to be around a "predator-prey" relationship, with CTL acting as the predator along with tumor cells acting as the prey. In this paper, we examined steady-state solutions for two numerical differentiation using the Jacobian matrix. We will also examine the stability region of breast cancer cells in two different phases to describe its progress in different types of the human body at various phases. Also, compare tumour cells population development in the duration of interphase and metaphase in the presence and the absence of immune response, which is dependent on the CTL population, will be observed by applying Fourth Order Runge Kutta (RK4) method. We can see that the Runge-Kutta method is an important method for approximate solutions to ordinary systems with known initial conditions. We achieved populations value of tumour cells throughout interphase and mitosis as well as the population of the immune system using the method. Based on our observations, we draw the conclusion that persons with a higher immune system are more likely to be able to fight cancer for for a period of time than cancer sufferers with a poor immune system. We may observe that the cancer cells were reduced in a shorter period of time with a high immune response population compared to other lower CTL values. [ABSTRACT FROM AUTHOR]

This paper is to contribute theoretical result of fixed-point approach for analysing the existence, uniqueness and stability of tumour growth in the different cases of drug free model. With the help of Picard theorem, we explore the existence of the drug-free model in the presence and absence of an immune response in the both delay and non-delay instance and Banach Contraction Principle is used to demonstrate the uniqueness of the model's solution. Moreover, the generalized Hyers-Ulam stability is being used for finding the stability conditions and stable interval. [ABSTRACT FROM AUTHOR]

TB and HIV infection have the effect of deeply on assault the immune system, since they can afford to weaken host immune respone through a mechanism that has not been fully understood. HIV co-infection is the stongest risk factor for progression of M. tuberculosis to active TB disease in HIV individuals ,as well as TB has been accelerated to progression HIV infection. In this paper we create a model of transmission co-infection TB in HIV community, dynamic system with ten compartments built in here . Dynamic analysis in this paper mentioned ranging from disease free equilibrium conditions, endemic equilibrium conditions , basic reproduction ratio, stability analysis and numerical simulation. Basic reproductive ratio were obtained from spectral radius the next generation matrix of the model. Numerical simulations are built to justify the results of the analysis and to see the changes in the dynamics of the population in each compartment. The sensitivity analysis indicates that the parameters affecting the population dynamics of TB in people with HIV infection is parameters rate of progression of individuals from the exposed TB class to the active TB, treatment rate of exposed TB individuals, treatment rate of infectious (active TB) individuals and probability of transmission of TB infection from an infective to a susceptible per contact per unit time. We can conclude that growing number of infections carried by infectious TB in people with HIV infection can lead to increased spread of disease or increase in endemic conditions. [ABSTRACT FROM AUTHOR]

The steady state properties for the effect of non-immunogenic microenvironmental factors on tumor growth dynamics in the presence of immune response is investigated. The corresponding Fokker-Planck equation to the Langevin model equation interpreted in the sense of Stratonovich is used to derive the steady state distribution ρst(x) and the mean (x)st of the tumor growth system. We find that the correlation strength φ stimulates the effect of the non-immunogenic microenvironmental factors σ on the tumor growth dynamics, and the tumor response M to the non-immunogenic microenvironmental factors within the tumor site may inhibits tumor growth, but not sufficient enough to cause extinction. Moreover, the result also indicates that the stronger the immune response λ the more the tumor population disappears. [ABSTRACT FROM AUTHOR]

We present a delay-dependent HTLV-I model with CTL immune response. The basic reproduction number is obtained for the existence of positive steady state. By constructing suitable Lyapunov functions, when the basic reproduction number is less than one, the infection-free steady state is globally asymptotically stable; when the basic reproduction number is greater than one, the infected steady state is globally asymptotically stable. [ABSTRACT FROM AUTHOR]

Dengue is a mosquito borne viral disease causing over 390 million infections worldwide per annum. Even though information on how infection is controlled and eradicated from the body is lacking, antibodies are thought to play a major role in clearing the virus. In this paper, a non-linear conceptual dynamical model with humoral immune response and absorption effect has been proposed for primary dengue infection. We have included the absorption of pathogens into uninfected cells since this effect causes the virus density in the blood to decrease. The time delay that arises in the production of antibodies was accounted and is introduced through a continuous function. The basic reproduction number R0 is computed and a detailed stability analysis is done. Three equilibrium states, namely the infection free equilibrium, no immune equilibrium and the endemic equilibrium were identified and the existence and the stability conditions of these steady states were obtained. Numerical simulations proved the results that were obtained. By establishing the characteristic equation of the model at infection free equilibrium, it was observed that the infection free equilibrium is locally asymptotically stable if R0 < 1. A threshold value for the antibody production rate was identified for which the infection gets completely cured even if R0 > 1. Stability regions are identified for infection free equilibrium state with respect to the external variables and it is observed as the virus burst rate increases, the stability regions would decrease. These results implied that for higher virus burst rates, other conditions in the body must be strong enough to eliminate the disease completely from the host. The effect of time delay of antibody production on virus dynamics is discussed. It was seen that as the time delay in production of antibodies increases, the time for viral decline also increased. Also it was observed that the virus count goes to negligible levels within 7 − 14 days after the onset of symptoms as seen in dengue infections. [ABSTRACT FROM AUTHOR]

The current study was designed to study the effect of silver nanoparticles, and LPS in immunoglobulin level. Silver nanoparticles and LPS were purchased from Sigma USA. SNPs and LPS were injected intraperitoneal in male mice for 3 weeks. The concentration of immunoglobulin levels was measured using single immune diffusion assay. The results of this study confirmed that the SNPs, and LPS increases IgM, IgG level. The results of this study prove the ability of silver nanoparticles and LPS as immune system inducer and we could use them in future in vaccines preparation. The purpose of the current work was to investigate the activity and ability of silver nanoparticles and LPS on mice humeral immunity. The results of this study showed that Silver nanoparticles and LPS induce a strong specific immune response. Taken together, the results of the present work demonstrated that Silver nanoparticles and LPS could be considered as an effective and alternative stimulator and inducer of immune system for prevention of microbial or bacterial infections. [ABSTRACT FROM AUTHOR]

Direct anti-viral agents (DAAs) allow to obtain the eradication of hepatitis C virus, but they do not prevent from possible re-infections. A vaccine can be useful to achieve this goal. Here, we study the global asymptotical stability (GAS) of the infection-free equilibrium for a recent model of hepatitis C, including immune response and alanine-aminotransferase production. Some suffcient conditions of global stability, based on the existence of a minimum positive antibody value, are obtained, thus confirming the importance of a post-therapy vaccine as an effective preventive defense to subsequent viral attacks. [ABSTRACT FROM AUTHOR]

A mathematical model for the study of the dynamics of Chronic Myelogenous Leukemia is developed. It takes into consideration the asymmetric division of Stem-like cells and the anti-leukemia immune response, focused on the dynamics of CD8+ cytotoxic T-cells. On the lines in the works of Kim et al ([7], [8]) the model can be used to better understand the evolution of the disease and for possible new therapeutical interventions. [ABSTRACT FROM AUTHOR]

The primary objective of this article is to introduce an immuno-epidemiological model of paratuberculosis (Johne's disease). To develop the immuno-epidemiological model, we first develop an immunological model and an epidemiological model. Then, we link the two models through time-since-infection structure and parameters of the epidemiological model. We use the nested approach to compose the immuno-epidemiological model. Our immunological model captures the switch between the T-cell immune response and the antibody response in Johne's disease. The epidemiological model is a time-since-infection model and captures the variability of transmission rate and the vertical transmission of the disease. We compute the immune-response-dependent epidemiological reproduction number. Our immuno-epidemiological model can be used for investigation of the impact of the immune response on the epidemiology of Johne's disease. [ABSTRACT FROM AUTHOR]

Many pathogens stimulate cell death of immune cells while promoting survival of pathogens. Early cell death is characterized by the release of mediators, namely Caspases (Cas). Infections caused by pathogens can be eradicated if immune cells could resist cell death and kill pathogens upon exposure. In this research, we studied whether glycoconjugates (GCs) influence Cas release and cytotoxicity upon pathogen damage. GC1 and GC3 constituted samples studied principally. Bacterial spores were used as a pathogen model. GC effects were determined “prior to,” “during,” and “following” pathogen exposure throughout phagocytosis. Cytotoxic damage was assessed by measuring lactate dehydrogenase (LDH) production. Our data show that GC3 was more effective than GC1 during phagocytosis. GC3 controls Cas release under all three exposure conditions. Minimum production of LDH was noticed in the “following” exposure condition compared to the “prior to” and “during” exposure conditions for GC1 and GC3. The present study provided the selection method of GC ligands bearing anti-cytotoxic and anti-apoptotic properties. [ABSTRACT FROM AUTHOR]

Members of the Bacillus cereus group demonstrate different pathological effects. B. cereus is a spore-forming, gram positive bacterium responsible for most foodborne illnesses. It was shown that susceptibility to infection and response to vaccines or treatments can be attributed to specific immunogenetic factors including gender and ethnicity. Glycoconjugate polymers (GCs) are potentially important in pharmaceutical and biomedical research. Our group has shown that GCs activate murine macrophages and promote killing of Bacillus cereus spores during phagocytosis. We hypothesized that the GCs effects are independent from gender and race. The goal of the present study was two-folds: A) determine whether GCs influence on human PMNC exposure of B. cereus spores and B) analyze whether gender and ethnicity influence of the effect of GCs. GCs were studied during exposure and post-exposure conditions. Phagocytosis was performed during exposure of PMNC to Bacillus spores. Post-exposure analysis involved cytotoxicity, cell viability and activation, and colonies forming unit. GC1 and GC3 enhance Bacillus spore killing. GC1 proved more effective than GC3 in spore killing while activating PMNC. Results demonstrate GCs effect were independent from ethnicity or gender. Findings of this research demonstrated that GC can be used as ligands to stimulate PMNC and kill B. cereus spores. [ABSTRACT FROM AUTHOR]

Peripheral mononuclear cells (PMNC) including macrophages are key players in the immune responses against pathogens. Any infection could be attenuated if PMNC would be activated and capable to kill pathogen on exposure. It was shown that glycoconjugates (GCs) play an important role in adhesion to, activation, and recognition of pathogens. Nitric oxide (NO) is a regulatory molecule released by immune cells against pathogens that include bacteria, protozoa, helminthes, and fungi. NO is a highly reactive and diffusible molecule that controls replication or intracellular killing of pathogens during infection and immune responses against infections caused by pathogens. Avirulent Bacillus anthracis Sterne spores were used as a model in our study. The purpose of this study was two-fold: A) to analyze PMNC activation through NO production and B) to determine the cytotoxicity effect based on lactate dehydrogenase (LDH) upon exposure to pathogen exerted by GCs. The latter were used “prior to,” “during,” and “following” PMNC exposure to pathogen in order to modulate immune responses to spores during phagocytosis. Post-phagocytosis study involved the assessment of NO and LDH release by macrophages upon exposure to spores. Results have shown that untreated PMNC released low levels of NO. However, in the presence of GCs, PMNC were activated and produced high levels of NO under all experimental conditions. In addition, the results showed that GC1, GC3 are capable of increasing PMNC activity as evidenced by higher NO levels under the “prior,” “during” and “following” to pathogen exposure conditions. On the other hand, GCs were capable of controlling cytotoxicity and decreased LDH levels during phagocytosis of spores. Our findings suggest that GCs stimulate NO production by activating PMNC and decrease cytotoxicity caused by pathogens on PMNC. [ABSTRACT FROM AUTHOR]

To determine whether HIFU treatment can elicit a systemic, anti-tumor immune response in vivo, MC-38 solid tumors grown subcutaneously at the right hindlimbs of C57BL/6 mice were treated in an experimental HIFU system. Three different treatment strategies that produce thermal, mechanical, or thermal combined with mechanical damage to the tumor tissue were evaluated. To detect anti-tumor immune response, a tumor challenge was performed on the left hindlimbs of the mice one day following the HIFU treatment, and subsequently, cytotoxic T lymphocyte (CTL) response was evaluated on day 14. All three HIFU treatment strategies were found to cause significant regression of the primary tumor, with the best suppressive effect produced by the thermal HIFU. In contrast, the most significant regression of the challenged tumor with concomitantly elevated CTL response were detected in mice treated by the mechanical HIFU, followed by the thermal combined with mechanical HIFU, but not in mice treated by the thermal HIFU alone. These findings suggest that alternative treatment strategies that promote mechanical lysis of the tumor cells (in contrast to purely thermal ablation) may enhance HIFU-induced anti-tumor immune response. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

NF-κB is a pleoiotropic transcription factor that controls the expression of a large number of genes involved in apoptosis, differentiation, cell growth and immune response. Alterations in NF-κB activity are associated with many diseases including cancer. In this work we show that NF-κB activation can be modulated by expression of nuclear protein pirin which might affect the effectiveness of anticancer therapies. [ABSTRACT FROM AUTHOR]