Congenital Human Cytomegalovirus and the Complement System

Andrea Canto Garon1, Yujun Liu2, Fenyong Liu1,2

  • 1Program in Comparative Biochemistry, University of California, Berkeley, CA 94720, USA.

Viruses
|October 29, 2025
PubMed

Insights

Congenital human cytomegalovirus (HCMV) infection can cause serious infant complications. This review hypothesizes that complement system dysregulation drives HCMV pathogenesis and neurodevelopmental issues, suggesting complement inhibition as a potential therapy.

Area of Science:

  • Immunology
  • Virology
  • Developmental Biology

Background:

  • Congenital human cytomegalovirus (HCMV) infection is a leading cause of birth defects, affecting 1 in 200 newborns globally.
  • While often asymptomatic at birth, congenital HCMV can lead to severe neurodevelopmental sequelae, including microcephaly and sensorineural hearing loss.
  • Current therapeutic options for pregnant individuals and preventive vaccines against HCMV are limited, highlighting an urgent need for novel strategies.

Purpose of the Study:

  • To review the dual role of the complement system in fetal development and HCMV pathogenesis.
  • To propose a hypothesis linking complement system dysregulation to congenital HCMV-related pathogenesis and neurodevelopmental abnormalities.
  • To explore therapeutic potential by examining how HCMV perturbs the complement system and the implications of complement inhibition.

Main Methods:

  • Literature review synthesizing current knowledge on the complement system's role in fetal development.
  • Analysis of existing research on HCMV pathogenesis and its interaction with the innate immune system.
  • Exploration of complement system dysregulation as a potential mechanism driving congenital HCMV sequelae.

Main Results:

  • The complement system is essential for fetal development and maternal immunity but can contribute to inflammation during HCMV infection.
  • HCMV infection may dysregulate the complement cascade, potentially exacerbating fetal damage and neurodevelopmental issues.
  • Evidence suggests that targeting the complement system could offer a novel therapeutic approach for congenital HCMV disease.

Conclusions:

  • A dysregulated complement system is hypothesized to be a critical factor in the pathogenesis of congenital HCMV infection and its associated neurodevelopmental complications.
  • Understanding HCMV's impact on the complement system provides insights into disease mechanisms.
  • Targeting the complement system presents a promising avenue for developing new treatments to mitigate the adverse effects of congenital HCMV infection.

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