Study On The Structural Changes Of Bacteria In Respiratory Tract Allergic Process

Objective:1.To analyze the bacterial abundance and variety in lower respiratory tract of normal people,allergic rhinitis patients and asthma patients,and to probe the bacterial abundance and variety in respiratory atopic march.2.To analyze the changes of bacterial composition in lower respiratory tract of normal people,allergic rhinitis patients and asthma patients,and to serch the bacterial species with accumulated variability in respiratory atopic march.3.To analyze the level of IgE in normal people,allergic rhinitis patients and asthma patients,and to probe the change of IgE in respiratory atopic march.Methods:1.50 allergic rhinitis patients and 50asthma patients were chosen from the first affiliated hospital of Dalian Medical University,according to the standard of asthma,without using any antibiotic or hormone in a month.50 healthy people were chosen from internal students as volunteers.Collecting clean and deep sputums and blood samples.2.15allergic rhinitis patients and 13 asthma patients and 15 volunteers from all the samples were chosen to extract DNA from the clean and deep sputum from volunteers and patients.DNA were sequenced by Miseq,in order to get the structure information of bacteria.3.Using bioinformatics methods to explore the important microbiota which is closely related with the occurrence and progression of the respiratory allergic process.4.50 blood samples were got from each group,and ELISA were used to measure IgE of the serum,then compared.Results:1.α diversity analysis of microbiome in lower respiratory tractCompared with the normal group,the number of OTU,the value of CHAO and ACE decreased significantly from allergic rhinitis group to asthma group.（p<0.05,p<0.001）.Compared with the normal group,the index of Shannon showed a decreasing trend,and the index of Simpson shows an upward trend.（p<0.001,p<0.05）2.Composition analysis of microbiome in lower respiratory tract（phylum level）Compared with the control group,the proportion of Firmicutes appeared a increasing trend in allergic rhinitis group,while it increased significantly（p<0.05）in asthma group.Compared with the control group,the proportion of Proteobacteria and Fusobacteria both decreased in allergic rhinitis group,while they decreased significantly（p<0.05,p<0.001）in asthma group.Compared with the control group,the proportion of Bacteroidetes decreased in allergic rhinitis group,while the proportion of Actinobacteria increased significantly（p<0.01）.the proportion of Bacteroidetes increased significantly（p<0.05）in asthma group,while the proportion of Actinobacteria decreased.3.Composition analysis of microbiome in lower respiratory tract（genus level）Compared with the control group,the ratio of Streptococcus in the allergic rhinitis group had an increasing trend,a further rise in asthma group.The proportion of Prevotella in the allergic rhinitis group increased,asthma group further increased significantly（p<0.05）.Neisseria in allergic rhinitis group was the proportion of decline,further decreased significantly in asthma group（p<0.01）.The proportion of Rothia in allergic rhinitis group（p<0.05）increased,while the proportion of Actinomyces increased.the proportion of Rothia increased in allergic rhinitis group,while Actinomyces decreased.The proportion of Veillonella was not obvious.4.Analysis of serum IgECompared with the control group,serum IgE level in allergic rhinitis group（p<0.001）and asthma group（p<0.001）were significantly increased,Compared with the allergic rhinitis group,the asthma group IgE increased further.Conclusion:1.In respiratory atopic march,the lower respiratory tract flora abundance and diversity showed a decreasing trend.2.In respiratory atopic march,the proportion of Firmicutes in the lower respiratory tract progressively increased,the proportion of Proteobacteria,Fusobacteria group progressively decreased.3.In respiratory atopic march,the proportion of Streptococcus,Prevotella₇ showed a rising trend,the proportion of Neisseria had a significant downward trend.4.In respiratory atopic march,in patients with allergic rhinitis and asthma group serum IgE index had asymptotic increasing trend.