Profiling Of Differential Expression In Peripheral Blood Mononuclear Cells Between Cough Variant Asthma And Typical Bronchial Asthma By Whole-genome Microarray

Background: Cough variant asthma(CVA)is one kind of bronchial asthma,because some CVA patients will develope to typical asthmatics,CVA is also known as the precursor of asthma.Early and correct treatment can partly avoid further development.However,the mechanism of typical asthma development has not yet been explored.Based on this,in order to find out the difference and elaborate the pathogenesis of asthma and the possible transitional mechanisms of CVA,we compared the differences of gene expressions in Peripheral blood mononuclear cells(PBMCs)among CVA,typical asthma and healthy people.Methods: Peripheral venous blood was collected from each cases of Healthy people,CVA patients and typical asthmatics groups.Each group has5 cases.PBMCs were isolated and total RNAs were extracted by Trizol.Then used Agilent 4 × 44 K human genome Oligo microarray to detect the whole genome expresssion and did allogeneic clustering and Gene Ontology functional analyses.Then we selected 10 differentially expressed and functional related genes as candidates.Finally,real-time PCR was performed to verify the gene microarray results.Results: Gene expression microarray found that there were 202 differently expressed genes in PBMCs between asthma group and CVA group,119 differently expressed genes between the healthy group and CVA group,779 differently expressed genes between healthy group and asthma group.Allthe differences were more than two-fold changes.The functional analysis of Gene Ontology suggested that the different genes were mainly related to epigenetics and antigen presentation and expression.The 10 candidate genes were HDC,EGR1,DEFA4,LTF,G0S2,IL4,TFF3,FCER1 A,CAMP,CTSG.Real-Time PCR results were not completely consistent with the gene microarray results.The expressions of FCER1 A,HDC and IL4 in CVA group were higher than that in healthy group and asthma group(P < 0.05),and their relative expression were(FCER1A)1.45×10-1±5.26×10-2,7.75×10-2±2.47×10-2 and 5.29×10-2±2.66×10-2;(HDC)2.86×10-2±1.47×10-2,8.89×10-3±3.4×10-3 and 7.44×10-3 ±5.29×10-3;(IL4)1.66×10-3±8.63×10-4,3.75×10-4±3.28×10-4 and 3.44×10-4±2.21×10-4.The expressions of EGR1,DEFA4,LTF,G0S2,TFF3,CAMP,CTSG genes in the three groups had no significant differences(P > 0.05).Conclutions: 1.In this study,gene expressions in PBMCs among CVA,typical asthma and healthy people were significantly different by whole-genome microarray.2.But the validation results by Real-Time PCR showed that the FCER1 A,HDC,IL4 genes in CVA group were up-regulated than those in healthy group and asthma group.And there were no statistical diffences of the expressions of EGR1,DEFA4,LTF,G0S2,TFF3,CAMP,CTSG genes in the three groups.This suggested that the pathogenesis of CVA may be related to FCER1 A,HDC,and IL4 genes whereas the other seven candidate genes may not be important in the pathogenesis of CVA...