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High complement factor I activity in the plasma of children with autism spectrum disorders
Naghi Momeni1, Lars Brudin, Fatemeh Behnia
1School of Natural Sciences, Linnaeus University, 39182 Kalmar, Sweden.
Insights
Children with autism spectrum disorder (ASD) show higher levels of complement factor I activity. This finding suggests a potential link between immune system complement factor I and ASD development.
Area of Science:
- Neuroimmunology
- Developmental Disorders
- Complement System Biology
Background:
- Autism spectrum disorders (ASDs) are neurodevelopmental conditions impacting social interaction, behavior, and communication.
- ASDs are frequently associated with immune system abnormalities.
- The complement system, particularly complement factor I, plays a role in immune regulation and host defense.
Purpose of the Study:
- To investigate the association between complement factor I activity and autism spectrum disorders.
- To explore the potential role of immune dysregulation in ASD pathogenesis.
Main Methods:
- Comparative analysis of complement factor I activity levels between a group of children with ASD and a control group of typically developing children.
- Assay of plasma samples to quantify factor I activity.
Main Results:
- The mean level of complement factor I activity was significantly higher in the ASD group compared to the control group.
- This elevated activity suggests a potential dysregulation of the complement system in individuals with ASD.
Conclusions:
- High complement factor I activity may be a contributing factor to the development of autism spectrum disorders.
- Further research into the neuroimmune mechanisms underlying ASD is warranted.
Abstract:
Autism spectrum disorders (ASDs) are neurodevelopmental and behavioural syndromes affecting social orientation, behaviour, and communication that can be classified as developmental disorders. ASD is also associated with immune system abnormality. Immune system abnormalities may be caused partly by complement system factor I deficiency. Complement factor I is a serine protease present in human plasma that is involved in the degradation of complement protein C3b, which is a major opsonin of the complement system. Deficiency in factor I activity is associated with an increased incidence of infections in humans. In this paper, we show that the mean level of factor I activity in the ASD group is significantly higher than in the control group of typically developed and healthy children, suggesting that high activity of complement factor I might have an impact on the development of ASD.
