Thepurposeofthisstudyistodistinguishrespiratorysyncytialvirus(RSV)infectionandimmunologybetweenimmunocompetentandimmunocompromisedmurineandtoexploreimmunemechanismofRSVinfection.AtvarioustimepointsafterRSVinfectionofBALB/cmiceandnudemice,pulmonaryviraltiterswereassayed,RSVantigenwastestedbydirectimmune-fluorescentassayandimmunohistochemistry.PulmonarymRNAexpressionsofTolllikereceptor(TLR)2andTLR4wereassayedbyRT-PCR.CD4+cellsandCD8+cellsinperipheralbloodwereexaminedbyflowcytometryandplasmatotalIgEwasassayedbyELISA.Leukocytesinbronchoalveolarlavagefluid(BALF)andpulmonaryhistologywereidentifiedtoreflectairwayinflammation.ItwasfoundthatRSVtitersofbothmicepeakedonthe3rddaypostinfectionwithamuchhigherlevelofviraltiterinnudemicethaninBALB/cmiceandalongerviraldurationinnudemice(over9dayspostinfection)thaninBALB/cmice(6dayspostinfection).RSVinfectioninducedhigherviralantigenexpressioninnudemice(0.267±0.045)thaninBALB/cmice(0.168±0.031).RSVinfectionenhancedpulmonaryTLR4expressionofBALB/cmice(51.96%±11.34%)andnudemice(48.96%±12.35%)comparedwitheachcontrol(34.04%±10.06%and32.37%±9.87%respectively).CD4+peripheralbloodcellsincreasedinRSVinfectedBALB/cmice(66.51%±2.09%)comparedwiththecontrolBALB/cmice(51.63%±5.90%),andCD4+cellsandCD8+cellsweredeficientinnudemice.RSVinfectionincreasedplasmatotalIgEinbothmice,andBALB/cmicehadalargeramountofIgEonthe7thdaypostinfection(9.02ng/ml±2.90ng/ml)andonthe14thdaypostinfection(12.76ng/ml±4.15ng/ml)thancorrespondingnudemice(3.72ng/ml±1.06ng/mland7.62ng/ml±3.08ng/mlrespectivelyonthe7thand14thdaypostinfection).RSVinfectednudemicehadmoresevereairwayinflammationthaninfectedBALB/cmice.ItisconcludedthatBALB/cmiceandnudemicepresentedsimilarRSVinfectiouscharacteristics.However,
