The Immune System is a complex adaptive system containing many details and many exceptions to established rules. Exceptions such as the suppression effect that causes T-cells to develop reversible aggressive and tolerant behaviors create difficulties for the study of immunology but also give hints to how artificial immune systems may be designed. Presented in this paper is the General Suppression Framework, which models the suppression hypothesis of the immune discrimination theory. A distributed control system based on the proposed framework is designed to control a modular robot configured into a planar manipulator arm. The modules can generate emergent group behaviors by exhibiting aggressive or tolerant behavior based on the environment change. A MATLAB simulation program is developed to demonstrate the effectiveness of the suppression mechanism and a mechanical arm is constructed to verify the control actions of the mechanism. The ultimate ambition of this work is to understand how the suppression mechanism affects the discrimination system and in turn affect other integral parts of the artificial immune system.