Presented antigen from damaged pancreatic β cells activates autoreactive T cells in virus-mediated autoimmune diabetes

In type 1 diabetes mellitus (T1DM), also known as autoimmune diabetes, the pathogenic destruction of the insulin-producing pancreatic β-cells is under the control of and influenced by distinct subsets of T lymphocytes. To identify the critical genes expressed by autoimmune T cells, antigen presenting cells, and pancreatic β-cells during the evolution of T1DM in the nonobese diabetic (NOD) mouse, and the genetically-altered NOD mouse (BDC/N), we used functional genomics. Microarray analysis revealed increased transcripts of genes encoding inflammatory cytokines, particularly interleukin (IL)-17, and islet cell regenerating genes, Reg3α, Reg3β, and Reg3γ. Our data indicate that progression to insulitis was connected to marked changes in islet antigen expression, β-cell differentiation, and T cell activation and signaling, all associated with tumor necrosis factor-α and IL-6 expression. Overt diabetes saw a clear shift in cytokine, chemokine, and T cell differentiation factor expression, consistent with a focused Th1 response, as well as a significant upregulation in genes associated with cellular adhesion, homing, and apoptosis. Importantly, the temporal pattern of expression of key verified genes suggested that T1DM develops in a relapsing/remitting as opposed to a continuous fashion, with insulitis linked to hypoxia-regulated gene control and diabetes with C/EBP and Nkx2 gene control.

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Nonlinear Analysis for a Type-1 Diabetes Model with Focus on T-Cells and Pancreatic β-Cells Behavior

Mathematical and Computational Applications ◽

10.3390/mca25020023 ◽

2020 ◽

Vol 25 (2) ◽

pp. 23

Author(s):

Diana Gamboa ◽

Carlos E. Vázquez ◽

Paul J. Campos

Keyword(s):

T Cells ◽

Type 1 Diabetes ◽

Cell Population ◽

Closed Loop ◽

Pancreatic Β Cell ◽

Activated Macrophages ◽

Β Cells ◽

Β Cell ◽

Pancreatic Β Cells

Type-1 diabetes mellitus (T1DM) is an autoimmune disease that has an impact on mortality due to the destruction of insulin-producing pancreatic β -cells in the islets of Langerhans. Over the past few years, the interest in analyzing this type of disease, either in a biological or mathematical sense, has relied on the search for a treatment that guarantees full control of glucose levels. Mathematical models inspired by natural phenomena, are proposed under the prey–predator scheme. T1DM fits in this scheme due to the complicated relationship between pancreatic β -cell population growth and leukocyte population growth via the immune response. In this scenario, β -cells represent the prey, and leukocytes the predator. This paper studies the global dynamics of T1DM reported by Magombedze et al. in 2010. This model describes the interaction of resting macrophages, activated macrophages, antigen cells, autolytic T-cells, and β -cells. Therefore, the localization of compact invariant sets is applied to provide a bounded positive invariant domain in which one can ensure that once the dynamics of the T1DM enter into this domain, they will remain bounded with a maximum and minimum value. Furthermore, we analyzed this model in a closed-loop scenario based on nonlinear control theory, and proposed bases for possible control inputs, complementing the model with them. These entries are based on the existing relationship between cell–cell interaction and the role that they play in the unchaining of a diabetic condition. The closed-loop analysis aims to give a deeper understanding of the impact of autolytic T-cells and the nature of the β -cell population interaction with the innate immune system response. This analysis strengthens the proposal, providing a system free of this illness—that is, a condition wherein the pancreatic β -cell population holds and there are no antigen cells labeled by the activated macrophages.

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