Optimized fast non-singular integral terminal sliding mode control of immune response and HCMV infection of renal transplant recipient.

Kidneys are the most commonly transplanted organs, and renal transplant is the best treatment for patients with advanced stages of renal disease. Immunosuppressive drugs are used after renal transplant to prevent the body from rejecting the transplanted kidney and ensure its proper kidney functioning. However, suppression of the immune system increases the risk of viral infections and other complications. Therefore, careful monitoring and management of immunosuppressive and antiviral drugs are essential for the success of the transplants. This article presents a hybrid fast non-singular integral terminal sliding mode control technique to adjust the efficacies of these drugs in renal transplant recipients, ensuring successful transplants and preventing viral infections. The proposed strategy tracks system trajectories to reference values and adjusts the treatment plan accordingly. The Lyapunov stability theorem is used to prove the asymptotic stability of the closed-loop system. Several simulation studies are conducted in MATLAB/Simulink environment to evaluate the performance of the proposed control technique in maintaining a balance between over-suppression and under-suppression. Genetic Algorithm is used to optimize the gain values to further improve the performance of the proposed control technique. Its performance is compared with two other variants of terminal sliding mode controllers to demonstrate its effectiveness against them.