Title: Revealing the Role of the Effector-regulatory T Cell Loop on Autoimmune Disease Symptoms via Nonlinear Dynamics
Reporter: ZHANG Wenjing(Texas Tech University)
Time: December 27, 2018 (Thursday) AM 10:00-10:45
Location: B1412# room, Innovation Park Building
Contact: A. Prof. LIU Liu (tel: 84708351-8141)
Abstract: In this talk, we investigate the influence of the effector-regulatory (Teff-Treg) T cell interaction on the T-cell-mediated autoimmune disease dynamics. The simple 3-dimensional Teff-Treg model is derived from the two-step model reduction of an established 5-dimensional model. The reduced 4- and 3-dimensional models preserve dynamical behaviors in the original 5-dimensional model, which represents the chronic and relapse-remitting autoimmune symptoms. Moreover, we find three co-existing limit cycles in the reduced 3-dimensional model, in which two stable periodic solutions enclose an unstable one. The existence of multiple limit cycles provides a new mechanism to explain varying oscillating amplitudes of lesion grade in multiple sclerosis. The complex multiphase symptom may be caused by a noise-driven Teff population traveling between two coexisting stable periodic solutions. The simulated phase portrait and time history of coexisting limit cycles are given correspondingly.
The brief introduction to the reporter: Dr. Wenjing Zhang, Assistant Professor in the Department of Mathematics and Statistic at Texas Tech University (TTU). Dr. Zhang is an Applied Mathematician who is interested in dynamical systems and its application in biology. She is studying mechanisms underlying infectious diseases and autoimmune diseases through deterministic and stochastic models. In her studies, deterministic disease dynamics are categorized in parameter spaces through bifurcation theory, more dynamics can appear with stochastic variations. Her work focuses on the recurrent phenomenon in HIV viral blips, relapse-remission pattern in autoimmune diseases, and uncontrolled cytokine flare-ups causing cytokine storms in SARS, Avian influenza, and Hantavirus cardiopulmonary syndrome. Dr. Zhang received her PhD in Applied Mathematics from Western University (University of Western Ontario) in Canada. Before joining the Department of Mathematics and Statistic at TTU she was a Postdoctoral Fellow in the Department of Mathematics and Statistics at York University (Canada). Recent Scholarship: Wenjing Zhang, Sophia Jang, Colleen B. Jonsson, and Linda J. S. Allen. Models of Cytokine Dynamics in the Inflammatory Response of Viral Zoonotic Infectious Diseases. To submit to Mathematical Medicine and Biology.