C4A and neoplasm: For instance, research has demonstrated that acupuncture and moxibustion can elevate key humoral immune markers such as IgM, IgG, C3, and C4 (48) and reduce TNF-α, TGF-β1 levels, increase IL-2 levels in tumor patients (24, 33, 41, 42), suggesting a potential mechanism for bolstering the body’s immune defenses against cancer.