Celiac disease and complement activation in response to Streptococcus pneumoniae.

Area of Science:

• Immunology
• Pediatrics
• Infectious Diseases

Background:

• Individuals with celiac disease (CD) exhibit a higher risk of invasive pneumococcal disease (IPD).
• The mechanisms underlying this increased susceptibility, beyond hyposplenism, are not well understood.

Purpose of the Study:

• To investigate if the complement system's response to Streptococcus pneumoniae differs between children with and without CD.
• To determine if complement activation could explain the elevated IPD risk in celiac disease patients.

Main Methods:

• Plasma from 22 children with CD and 18 controls was incubated with Streptococcus pneumoniae.
• Levels of complement activation products (C3a and sC5b-9) were measured using ELISA.
• Comparison of activation levels between stimulated and non-stimulated plasma within and between groups.

Main Results:

• Pneumococcal stimulation significantly increased C3a and sC5b-9 levels in both celiac disease patients and controls.
• No statistically significant difference in the magnitude of complement activation was observed between the CD group and the control group.
• C3a increased approximately 4.6-fold and sC5b-9 increased approximately 22-fold in both groups post-stimulation.

Conclusions:

• The complement response to Streptococcus pneumoniae appears comparable in children with and without celiac disease.
• This similarity suggests that complement activation is unlikely to be the primary factor contributing to the increased risk of invasive pneumococcal disease in individuals with celiac disease.