Encyclopedia of Medical Immunology

Living Edition
| Editors: Ian MacKay, Noel R. Rose

C1 Deficiency and Associated Disorders

  • Berhane GhebrehiwetEmail author
Living reference work entry
DOI: https://doi.org/10.1007/978-1-4614-9209-2_11-1


The complement system is a strictly regulated and highly complex effector system whose major function is to recognize and eliminate pathogens as well as altered self-antigens. Therefore, it constitutes a very powerful arm of the innate and adaptive immune systems with unique ability to discriminate self from nonself and eliminate “danger” through a wide array of processes that include phagocytosis and cytolytic mechanisms. Although there are three interdependent pathways of complement activation – classical, alternative, and lectin – only the role of the classical pathway and the consequences of deficiency in any of the components that initially trigger its activation are discussed here. The first component of complement (Table 1) is a multimolecular complex comprising of one molecule of C1q and the Ca 2+-dependent tetramer – C1r-C1s-C1s-C1r – which give rise to the pentameric complex: C1q.C1r 2.C1s 2found in plasma. Each molecule within this complex plays a sequential and...
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© Springer Science+Business Media LLC 2016

Authors and Affiliations

  1. 1.The Department of MedicineStony Brook UniversityNew YorkUSA
  2. 2.Health Sciences CenterStony Brook University School of MedicineNew YorkUSA

Section editors and affiliations

  • Kathleen Sullivan
    • 1
  1. 1.University of PennsylvaniaPhiladelphiaUSA