Activity OverviewThe creation of the Rheum4Science program grew out of the conviction that teaching science is important for rheumatologists in training and that adult learners benefit from a variety of resources and formats. Rheum4Science interactive modules teach the underlying immunology and clinical research methodology necessary for the knowledgeable practice of rheumatology. Complement activation is essential for human survival. Complement abnormalities of under- and over-activation have multiple adverse effects on inflammation and immunity.  This activity reviews the pathways of complement activation, its normal functional roles, and some key aspects of complement abnormalities that contribute to human disease.Rheum4Science SeriesThis activity is part of a series. See the other activities in the series below.Rheum4Science – ImmunologyRheum4Science: Overview of Innate ImmunityRheum4Science: Toll-Like ReceptorsRheum4Science: The NLRP3 InflammasomeRheum4Science: Complement PathwaysRheum4Science: Fundamental Principles of B Cell ImmunobiologyRheum4Science: T Cells - What Every Rheumatologist Needs to KnowRheum4Science: NeutrophilsRheum4Science – Immunopathogenesis of Rheumatic DiseaseRheum4Science: Pathogenesis of Rheumatoid ArthritisRheum4Science – Clinical Research MethodologyRheum4Science: Data & DistributionRheum4Science: Cohort StudiesRheum4Science: Randomized Controlled Trials Registration is complimentary.Target AudienceRheumatology fellows in training. This activity may also be of interest to medical students, residents, practicing rheumatologists, and other rheumatology health care providers interested in strengthening their understanding of basic scientific principles and clinical research methodology relevant to the field of rheumatology.Learning ObjectivesUpon completion of this activity, participants should be able to:Compare the three complement pathways – understand how their unique and shared components function in normal immune response.Describe the effects of complement activation on innate and adaptive immunity in both normal and pathologic states.Discuss consequences of complement component deficiencies, including associations with known diseases.Explain how complement pathways are regulated and give examples of disorders that arise from regulatory dysfunction.CE & MOC InformationThis activity is not eligible for CME/MOC.Acknowledgement of Commercial SupportNo commercial support was provided for this activity.Educational Activity PoliciesSee ACR educational activity policies, including the online enduring activity refund policy.