Related Experiment Videos
Serum complement levels in infancy: age related changes
Insights
Infant complement protein levels, including Clq and properdin, are low at birth and gradually increase towards adult ranges by 6-21 months. Clq levels correlate with IgG in older infants.
Area of Science:
- Immunology
- Pediatric Medicine
- Biochemistry
Background:
- The complement system is crucial for innate immunity.
- Complement component levels in neonates and infants are not well-established.
- Understanding these levels is vital for assessing immune function in early life.
Purpose of the Study:
- To determine the developmental trajectory of complement components and control proteins in infants.
- To compare complement levels in neonates, infants, and adults.
- To investigate the relationship between Clq, properdin, and IgG levels in infants.
Main Methods:
- Quantification of eight complement components and two control proteins in cord serum and infant serum (1 and 6 months).
- Measurement of serum Clq and properdin levels in a larger cohort (271 patients, ages 1-36 months).
- Statistical analysis to determine mean values, standard deviations, and correlations.
Main Results:
- All measured proteins were below adult levels at birth, rising by 6 months.
- Clq and properdin levels were significantly below adult ranges in early infancy, reaching adult levels by 18-21 months.
- Clq concentration showed higher variability; Clq levels correlated with IgG in infants aged 11 months to 3 years, but properdin did not.
Conclusions:
- Complement component levels mature significantly during the first year of life.
- Specific components like Clq and properdin show delayed maturation into the second year.
- The correlation between Clq and IgG suggests a potential interplay in immune development during infancy.
Abstract:
Levels of eight complement components and two control proteins, were determined on cord serum from normal full term neonates and serum from healthy infants aged 1 and 6 months. For all proteins, the levels were below the adult normal at birth and rose toward the adult range by age 6 months. In a second group of 271 patients, ages 1-36 months, serum Clq and properdin levels were measured. For both proteins, the mean values in early infancy were more than two SD below the adult range and did not reach the adult range until 18-21 months of age. The Clq concentration was more variable than that for any other component studied. In infants from 11 months-3 yr of age, Clq levels correlated with serum IgG levels, but properdin levels did not.