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An In vitro Model to Study Immune Responses of Human Peripheral Blood Mononuclear Cells to Human Respiratory Syncytial Virus Infection
Published on: December 10, 2013
Attenuated interleukin-8/leukocyte immunoresponse in preterm infants compared with term infants hospitalized with
Dagnachew Assefa1, Nikhil Amin, Allen J Dozor
1Respiratory Center for Children, Goryeb Children's Hospital, Atlantic Health, Morristown, NJ 07962, USA. assefad@gmail.com
Insights
Preterm infants hospitalized with respiratory syncytial virus (RSV) bronchiolitis show a weaker immune response compared to term infants. This difference in immune response may contribute to increased risks for severe outcomes in preterm infants.
Area of Science:
- Neonatology
- Pediatric Infectious Diseases
- Immunology
Background:
- Preterm (PT) infants face higher risks from respiratory syncytial virus (RSV) bronchiolitis due to reduced antibody transfer and altered immune responses.
- Understanding immune differences between preterm and term infants hospitalized with RSV bronchiolitis is crucial for risk assessment.
Purpose of the Study:
- To investigate and compare the immune responses in preterm versus term infants hospitalized with RSV bronchiolitis.
- To determine if immune responses correlate with clinical disease severity in these infant groups.
Main Methods:
- Collected nasal wash samples from 11 preterm (<37 weeks gestation) and 13 term (≥37 weeks gestation) infants hospitalized with RSV bronchiolitis.
- Assayed leukocyte counts and levels of cytokines (interleukin-8, IL-4, interferon-γ) in nasal washes.
- Compared clinical scores, oxygen saturation, and supplemental oxygen requirements between groups.
Main Results:
- No significant differences in clinical scores or oxygenation were observed between preterm and term infants.
- Term infants exhibited higher nasal wash leukocyte counts and IL-8 levels compared to preterm infants.
- Higher IL-8 levels correlated with increased clinical severity in term infants, but not in preterm infants.
Conclusions:
- Preterm infants hospitalized with RSV bronchiolitis demonstrate lower nasal wash leukocyte counts and a diminished IL-8 response compared to term infants.
- The IL-8 response in preterm infants did not correlate with clinical disease severity, unlike in term infants.
- These findings suggest a potentially less robust immune response in preterm infants during RSV bronchiolitis hospitalization.
Abstract:
Decreased transplacental transfer of antibodies and altered immunoresponsiveness may place preterm (PT) infants at higher risk for serious consequences from respiratory syncytial virus (RSV) bronchiolitis. We hypothesize that among infants hospitalized with RSV bronchiolitis, immune response in PT infants may be different when compared with that of term infants. Nasal-wash samples were collected from 11 PT (<37 weeks of gestation) and 13 term infants (≥37 weeks of gestation) hospitalized with RSV bronchiolitis. Severity of illness (clinical score [CS]), admission peripheral oxygen saturation, and days subjects required supplemental oxygen were compared. Nasal-wash leukocyte count as well as cytokines for interleukin (IL)-8, IL-4, and interferon-γ (IFN-γ) were assayed. No significant differences in CS, admission SaO(2), and O(2) days were seen between PT and term infants. Nasal-wash leukocyte counts and IL-8 levels were higher in term infants compared with PT and correlated with severity (higher CS) in term (p < 0.05) but not in PT (p > 0.05) infants. IL-4 and IFN-γ levels did not differ between the 2 groups (p > 0.05). PT infants hospitalized with RSV bronchiolitis have lower nasal-wash leukocyte counts and a less robust IL-8 response than term infants, and only in term infants did IL-8 levels correlate with clinical disease severity.

