High body temperature, supports immune function Non-specifically engulfs pathogens, toxins, and cellular debris Enhances phagocytosis, 1. Complement stimulates inflammation, and can destroy bacteria 2. Fever directly Performed by NK cells, 3. Phagocytic cells neutrophils, and other leukocytes; results in the 4. Non-phagocytic killing death of abnormal or nonself cells through non- 5. Interferons specific means Cell-signaling molecules that stimulate anti-viral defenses among other .