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Peptide-based Identification of Functional Motifs and their Binding Partners
14:28

Peptide-based Identification of Functional Motifs and their Binding Partners

Published on: June 30, 2013

Activation of the complement system in human immunodeficiency virus infection: relevance of the classical pathway to

G Senaldi1, M Peakman, T McManus

  • 1Department of Immunology, King's College School of Medicine and Dentistry, London, United Kingdom.

The Journal of Infectious Diseases
|December 1, 1990
PubMed

Insights

Complement pathway activation is linked to human immunodeficiency virus (HIV) disease progression. Increased classical complement pathway activation correlates with worsening HIV infection markers and declining CD4+ lymphocyte counts.

Area of Science:

  • Immunology
  • Virology

Background:

  • In vitro studies suggest complement pathway activation contributes to human immunodeficiency virus (HIV) pathogenesis.
  • The in vivo relevance of classical and alternative complement pathways in HIV infection requires further investigation.

Purpose of the Study:

  • To evaluate the in vivo significance of complement pathway activation in HIV-infected individuals.
  • To correlate complement activation markers with disease progression and immune status.

Main Methods:

  • Measured classical (C4d), alternative (Ba), and common (C3d) complement pathway activation fragments and ratios in 74 HIV-infected patients.
  • Related fragment levels to circulating immune complex (CIC) levels, Centers for Disease Control (CDC) stage, beta 2-microglobulin, neopterin, and CD4+ lymphocyte counts.

Main Results:

  • All measured complement fragments and ratios were significantly elevated in HIV patients compared to controls.
  • Classical pathway activation indices (C4d, C4d to C4) increased with disease severity (CDC stage) and correlated with elevated CIC and beta 2-microglobulin.
  • Classical pathway activation correlated inversely with CD4+ lymphocyte counts, indicating a link to immune decline.

Conclusions:

  • In vivo complement pathway activation, particularly the classical pathway, is significantly associated with HIV infection.
  • Classical complement pathway activation appears to play a role in HIV disease progression and immune deterioration.

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