Research Of Significances Of Detection Of T Cell Subsets, ICAM-1 And RANTES In Infants With Bronchiolitis

Bronchiolitis is a infectious disease that frequently threatens the children younger than two years old in lower respiratory tract and it is also one of the most common asthmatic disease in infants. The main features of bronchiolitis are breathe heavly, three depressions sign and stridor. Epidemiological studies have shown that 50%-70% of children with bronchiolitis can be repeated wheezing and even be developed to asthma and it has the upward trend in recent years. The exact pathogenesis of bronchiolitis has not yet clearly. There is no specific treatment of clinical and the main treatment method is only symptomatic supportive care. Present study suggests that bronchiolitis is a secondary immune dysfunction disease after infection. A variety of immune cells, cytokines and chemokines involve in the pathogenesis of bronchiolitis. In this paper, we detect the expressions of T cell subsets of CD4, CD8 and ICAM-1 (CD54) in peripheral blood and serum level of RANTES.We study the correlations between them and explore the possible pathogenesis of bronchiolitis in order to provide experimental bases for finding new treatment methods and further understanding pathogenesis of bronchiolitis.Material and Method1 Research Objects30 bronchiolitis children,26 bronchopneumonia children and 26 normal control children were divided into three groups. All children included in the experiment didn't have treatment history of immune drug one month before blood collection and they didn't have history of other diseases nearly 2 weeks.The pneumonia group and control group of children didn't have history of bronchiolitis, personal or family history of asthma and other history of allergic diseases. It was not statistically significant that the differences of age and sex among the three groups.2 Specimen Collection3 ml venous blood of the three groups of children was collected before they got treatment.2ml of them did not have anticoagulant and were centrifuged for 10 minutes at the speed of 3000r/min, then, we froze the serum under the conditions of-80℃. The other 1ml of fresh whole blood were centrifuged using EDTA-2Na.3 Experimental MethodsThe expressions of CD4+, CD8+T cell and ICAM-1 were detected by flow cytometry within 24 hours and the level of RANTES was assayed with ELISA technique in their serum.4 Statistics AnalysisThe results were demonstrated by means±standard deviation or median(P25-P75). We analyzed the results using one-way analysis of variance or Kruskal-Wallis Test among the three groups and the correlations using linear correlation analysis with statistics software SPSS 16.0. The mean difference was significant at the 0.05 level and P value less than 0.05 indicated statistical significance.Results1 T cell subgroupsThe levels of CD4 were 37.31±11.09,32.73±8.33,32.48±7.67% in the bronchiolitis group, bronchopneumonia group and control group.There were no statistical differences in the levels of CD4 in the three groups(P>0.05). The levels of CD8 were 21.53±5.91,24.38±7.27,24.56±4.96% in the bronchiolitis group, bronchopneumonia group and control group. There were no statistical differences in the levels of CD8 in the three groups(P>0.05). However, the ratio of CD4/CD8 in the bronchiolitis group[1.96(1.43-2.23)] was significantly higher than that in the bronchopneumonia group[1.31(1.01-1.98); P<0.05] and control group[1.22(1.03- 1.54); P<0.05]. It in the bronchopneumonia group had no difference compared with that in the control group(P>0.05)2 ICAM-1The ICAM-1 level in the bronchiolitis group(34.62±9.78%) was much higher than that in the bronchopneumonia(30.18±7.68%; P<0.05) and the control group(24.83±6.77%; P<0.01).The bronchopneumonia group had higher ICAM-1 level than the control group(P<0.05)3 RANTESThe RANTES level in the bronchiolitis(32.33±5.83 ng/ml) and the bronchopneu-monia group(30.40±6.11 ng/ml) was significantly higher than that in the control group(27.06±5.85 ng/ml) (P<0.01, P<0.05, respectively), however, no significant difference was found between the bronchiolitis and the bronchopneumonia group.4 Linear Correlation AnalysisThere was a positive correlation between ICAM-1 and RANTES levels in the bronchiolitis group (r=0.732, P<0.01), but there were not any correlation in the bronchopneumonia and control group.Conclusion1 Aberrant expression of T cell subsets together with ICAM-1 and RANTES are involved in progess of bronchiolitis.2 ICAM-1 and RANTES having a synergy are involved in progess of bronchiolitis.3 T cell subsets, ICAM-1 and RANTES can be used as indicators of bronchiolitis. These can provide some new bases and ideas for further understanding pathogenesis of bronchiolitis.