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Antibody Binding Specificity for Kappa (Vκ) Light Chain-containing Human (IgM) Antibodies: Polysialic Acid (PSA) Attached to NCAM as a Case Study
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Antibody Binding Specificity for Kappa (Vκ) Light Chain-containing Human (IgM) Antibodies: Polysialic Acid (PSA) Attached to NCAM as a Case Study

Published on: June 29, 2016

Mannan-binding-lectin-associated serine proteases, characteristics and disease associations

Rikke Sørensen1, Steffen Thiel, Jens C Jensenius

  • 1Department of Medical Microbiology and Immunology, Wilhelm Meyers Allé, University of Aarhus, 8000 Aarhus, Denmark. rs@microbiology.au.dk

Springer Seminars in Immunopathology
|September 29, 2005
PubMed

Insights

Mannan-binding lectin (MBL)-associated serine protease 2 (MASP-2) deficiency, caused by a specific mutation, leads to impaired immune function and increased susceptibility to infections and autoimmune disorders. This genetic defect impacts complement system activation.

Area of Science:

  • Immunology
  • Complement System Biology

Background:

  • Mannan-binding lectin (MBL)-associated serine proteases (MASPs) are crucial for the lectin pathway of complement activation.
  • MASP-2 cleaves C4 and C2, forming the C3 convertase, essential for immune responses.
  • MBL deficiency is common and linked to infections and autoimmunity; MASP functions are less understood.

Purpose of the Study:

  • To elucidate the role of MASP-2 in the complement system.
  • To describe a specific mutation causing inherited MASP-2 deficiency.
  • To investigate the clinical consequences of MASP-2 deficiency.

Main Methods:

  • Analysis of complement pathway activation.
  • Genetic sequencing to identify mutations.
  • Clinical case study of an affected individual.

Main Results:

  • A mutation (Asp105Gly) in the CUB1 domain of MASP-2 was identified, disrupting MBL/ficolin binding and abolishing MASP-2 activity.
  • The index case presented with severe recurrent infections and autoimmune reactions.
  • The mutation frequency in Caucasians is 3.6%, with different mutations found in other populations.

Conclusions:

  • Inherited MASP-2 deficiency results from specific genetic mutations.
  • MASP-2 is critical for complement activation and immune homeostasis.
  • MASP-2 deficiency leads to significant clinical manifestations, including infections and autoimmunity.

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