Relationship Between Cord Blood Th17Interrelated Cytokines And Infectious Disease In Infants

ObjectiveInfectious diseases are common in children, especially in the first year of life, which cause serious damage to the health of children. Low birth weight, premature birth and male gender are some of the factors that are associated with infectious illnesses. Despite these risk factors, however, some children tend to have more frequent or severe infectious illnesses than others. So we speculate that the development of natural immune system and whose influence to the development of adaptive immune system may affect a child’s subsequent clinical and immunologic responses to infectious diseases.As we know, innate immune system plays a dominant part in neonatal immune system and the cytokine regulation network plays an important link role between innate immune system and adaptive immune system.Th17cells are a new linage of T helper cells, which were identified in recent studies and produce IL-17primarily. At present, we hold the opinion that these cells play an important role in mediating inflammation and the cytokines they produced play an important part in the pathogenesis of inflammation, autoimmune disease, tumor, and other disease. In recent years, studies prove that Th17interrelated cytokines, such as IL-17, participate in anti-infection immune response. But the role of Th17interrelated cytokines in the innate immune system is still not clear, as well as the influence to the development of the adaptive immune system. So far, we know little of relationship between cord blood Th17interrelated cytokines and infectious disease in infants. The purpose of this study is to investigate the relationship between the level of Th17interrelated cytokines (such as IL-17、IL-23) produced by CBMC in cord blood and infectious illnesses. Discuss the status of Thl7interrelated cytokines in early immune to fight infection, in order to find the objective targets to be able to predict the early immune. This may provide more beneficial understanding of the clinical treatment and prevention of infectious illnesses.Methods1. The selection standards of the experiment objects:174neonates of full term normal newborns being breastfeed after birth, whose mothers have a healthy body in the gestation period and had not used drugs before delivery.2. The collection and processing of specimens:Cord blood samples were collected immediately by syringe from the umbilical vein after delivery. CBMC were isolated from umbilical cord blood by density gradient centrifugation with Ficoll-Hypaque plus, which were stimulated with PHA (10μg/ml) and then be incubated in carbon dioxide incubator. Cell supernatant fluids were harvested72hours after stimulation, which were kept in the-70℃refrigerator.3. Serologic tests:Analyze these174cell supernatant fluids for cytokine (IL-17v IL-23、INF-γ) production by enzyme-linked immunosorbent assay according to the manufacturer’s instructions.4. Follow-up visit:The number of all sorts of infection diseases happened in the first year of life was followed-up and recorded. The clinical diagnosis of infectious disease based on PRACTICE OF PEDIATICS (the seventh edition) and PEDIATICS (the seventh edition). The research objects were divided into groups according to infectious frequently.5. Statistical analysis:All the data was performed using SPSS18.0statistical software. Results were expressed as mean±standard deviation(SD). Oneway ANOVA and simple correlation analysis statistical methods were used to analysis data. The level of significance was set to P<0.05. Results1. There are no significant difference for IL-17A between group4and group5(P>0.05), there are significant difference for IL-17A among other groups (P<0.05)。2. There are no significant difference for IL-23between group1and group2, as well as group4and group5(P>0.05), there are significant difference for IL-23among other groups (P<0.05)。3. There are no significant difference for IFN-y among0group,1group,2group and3group, as well as group1and group2, group4and group5(P>0.05). There are significant difference for IFN-γ among other groups P<0.05)。4. There are correction between the three kinds of cytokines and infectious diseases in infants (P<0.05), the correction between IFN-y and infectious diseases is strongest (Pearson correlation coefficient=-0.571), flowed by the correction between IL-17A and infectious diseases (Pearson correlation coefficient=-0.430), the correction between IL-23and infectious diseases is weakest (Pearson correlation coefficient=-0.240)。5. There are negative correlation between IFN-γ、IL-17A and the number of respiratory infection in infant (P<0.05), there are no correction between IL-23and the number of respiratory infection in infant (P>0.05)。6. There are negative correlation between IFN-γ、IL-23and the number of digestive system infection in infants (P<0.05), there are no significant correction between IL-17A and the number of digestive system infection in infants (P>0.05)。7. There is no significant correction between the number of the three kinds of cytokines and urinary tract infections in infants (P>0.05)Conclusion1. There are negative correlation between cord blood IL-17A、IL23、IFN-γ and the number of infectious disease in infants, suggesting that IL-17A、IL23and FN-y are engaging in the body’s immune response fight to infection.2. Th17interrelated cytokines in cord blood may effect the occurrence and the development of infectious diseases by influencing both the condition of natural immune system and the development of adaptive immune system.3. INF-γ is still the main cytokine involving in inflammation, although Th17interrelated cytokines play important roles in immune response to fight infection.