Analysis of the Complement System in the Clinical Immunology Laboratory

Morris Ling; Mandakolathur Murali

doi:10.1016/j.cll.2019.07.006

Analysis of the Complement System in the Clinical Immunology Laboratory

Clin Lab Med. 2019 Dec;39(4):579-590. doi: 10.1016/j.cll.2019.07.006. Epub 2019 Oct 3.

Authors

Morris Ling¹, Mandakolathur Murali²

Affiliations

¹ Division of Rheumatology, Allergy and Immunology, Department of Medicine, Massachusetts General Hospital, 55 Fruit Street, Cox 201, Boston, MA 02114, USA; Center for Immunology and Inflammatory Diseases, Massachusetts General Hospital, 55 Fruit Street, Cox 201, Boston, MA 02114, USA; Department of Pathology, Massachusetts General Hospital, 55 Fruit Street, Cox 201, Boston, MA 02114, USA; Department of Medicine, Harvard Medical School, 55 Fruit Street, Cox 201, Boston, MA 02114, USA. Electronic address: mling@mgh.harvard.edu.
² Division of Rheumatology, Allergy and Immunology, Department of Medicine, Massachusetts General Hospital, 55 Fruit Street, Cox 201, Boston, MA 02114, USA; Department of Pathology, Massachusetts General Hospital, 55 Fruit Street, Cox 201, Boston, MA 02114, USA; Department of Medicine, Harvard Medical School, 55 Fruit Street, Cox 201, Boston, MA 02114, USA.

PMID: 31668271
DOI: 10.1016/j.cll.2019.07.006

Abstract

The complement system is a critical component of both the innate and adaptive immune systems that augments the function of antibodies and phagocytes. Antigen-antibody immune complexes, lectin binding, and accelerated C3 tick-over can activate this well-coordinated and carefully regulated process. The importance of this system is highlighted by the disorders that arise when complement components or regulators are deficient or dysregulated. This article describes the pathways involved in complement activation and function, the regulation of these various pathways, and the interpretation of laboratory testing performed for the diagnosis of diseases of complement deficiency, exuberant complement activation, and complement dysregulation.

Keywords: Alternative pathway; C3; C4; CH50; Classical pathway; Complement; Lectin pathway; Membrane attack complex.

Publication types

Review

MeSH terms

Complement C3-C5 Convertases / analysis
Complement C3-C5 Convertases / metabolism
Complement C3-C5 Convertases / physiology
Complement System Proteins* / analysis
Complement System Proteins* / metabolism
Complement System Proteins* / physiology
Hereditary Complement Deficiency Diseases* / blood
Hereditary Complement Deficiency Diseases* / diagnosis
Humans
Immunologic Tests*
Models, Biological

Substances

Complement System Proteins
Complement C3-C5 Convertases