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[Expression of CD21 in peripheral blood B lymphocytes of neonates]
Rong Zhang1, Qiong-Jin Wang, Jin-Mei Xu
1Department of Pediatrics, Yangzhou First People's Hospital, Yangzhou, Jiangsu, China. meltzhang@yahoo.com.cn
Insights
Neonates exhibit lower CD21 expression on B lymphocytes, correlating with reduced humoral immunity and immunoglobulin synthesis. This CD21 expression increases with age, indicating its role in developing immune function.
Area of Science:
- Immunology
- Pediatrics
- Flow Cytometry
Context:
- Neonates often present with suboptimal immune responses and insufficient immunoglobulin production.
- Understanding the B lymphocyte development and function in early life is crucial for addressing neonatal immune deficiencies.
Purpose:
- To investigate the relationship between CD21 expression on B lymphocytes and the impaired humoral immunity observed in neonates.
- To compare CD21 expression levels across different pediatric age groups.
Summary:
- This study analyzed CD21 expression in B lymphocytes from neonates (2-26 days), infants/toddlers (6 months-2 years), and older children (3-12 years) using flow cytometry.
- Neonate B lymphocytes showed significantly lower CD21 expression (percentage, number, and MFI) compared to older children.
- Serum IgA and IgM levels were also lower in neonates and increased with age, mirroring CD21 expression patterns.
Impact:
- Findings suggest that reduced CD21 expression on neonatal B lymphocytes may underlie their diminished humoral immune function.
- This research highlights CD21 as a potential marker for assessing B cell maturation and immune competence in infants.
- The study provides insights into the developmental trajectory of humoral immunity from infancy through childhood.
Objective:
To study the cause of low immunologic function and insufficiency of immunoglobulin synthesis in neonates by detecting CD21 expression in B lymphocytes in different age group children.
Methods:
This study consisted of three age group children: 2-26 days (n=18), 6 months-2 years (n=12) and 3-12 years (n=17). CD21 expression in B lymphocytes was detected with flow cytometry. Serum levels of immunoglobulins were measured by immunoturbidimetry.
Results:
The percentage and the number of B lymphocytes expressing CD21 in the neonate group were significantly lower than in the other two age groups. The neonate group also showed lower mean fluorescence intension (MFI) of CD21. The percentage and the number of B lymphocytes expressing CD21 as well as the MFI of CD21 increased significantly with the age. The serum levels of IgA and IgM in the neonate group were noticeably lower than those in the other two age groups. The serum levels of IgA and IgM also increased significantly with the age.
Conclusions:
Low CD21 expression in B lymphocytes may be related to low function of humoral immunity in neonates.
