Analysis Of HIV-1 Quasispecies Polymorphism In Mother And Child Based On Deep Sequencing Technology

Objective:Understand the infection status of newborns exposed in the study areas and initially explore the propagation and evolution of quasispecies of HIV-1 in intrauterine infection.To analyze the effect of different antiviral drug treatment regimens on the occurrence of primary drug-resistant strains of neonates.And to explore the potential impacts of two antiviral treatment regimens on the evolution of neonatal virus quasispecies,providing reference for optimizing neonatal prophylaxis and treatment regimens.Methods:The HIV-1 positive pregnant women who didn't use antiviral drugs or after labor and their newborn babies were collected in the study area.According to the principle of randomization,the exposed newborns were divided into intervention group and control group,and different antiviral prophylactic treatment programs were implemented.HIV-1 nucleic acid qualitative test was carried out to identify the infection status of the newborns,and three cases of intrauterine infection were identified.The first part of the study was to collect the blood-spots during the puerperium of neonates with intrauterine infection and their mother's maternal whole blood and plasma samples.The second part is to collect dry blood spot samples of infants at birth time,6 weeks and 3 months after treatment.The virus subtypes and drug-resistant mutants of all samples were detected by one generation sequencing technology.The quasispecies distribution of virus three gene region?GAG,POL and ENV regions?was detected by deep sequencing technology.Results1.The positive rates of newborn babies in Yunnan,Guangxi,Sichuan,Xinjiang and Guangdong were 9.38%,17.39%,7.02%,7.69%and 0,respectively.2.For intrauterine infection pairs,2 pairs of virus subtypes were CRF07_BC and 1 pairs were CRF₀8BC.No drug resistance mutation was detected in all the samples.3.The results of deep sequencing showed that the quasispecies complexity of maternal blood was higher than that of plasma,while the quasispecies complexity of neonatal whole blood samples was lower than that of the former two.It can be found that the newborn is infected with most of the virus quasispecies in the mother.4.Results of virus subtypes in 8 infants:4 cases of CRF08 BC,2 cases of CRF07_BC,1 case of B,and 1 case of CRF01_AE.One infant in the control group was found to have Y181C resistance mutations.None of the other samples detected resistance mutations.5.There was no difference in the complexity of the baseline samples between the intervention group and the control group.Comparing the quasispecies complexity the former was more dispersed than the latter,and the quasispecies of the virus was less complex,which was reflected obviously in ENV region.6.The viral variation of infants receiving single antiviral therapy increased with time and the gene distance between baseline samples increased.The gene distance of infants receiving triple-drug treatment between the monitoring time points and the baseline samples increased slowly,but there was a downward trend at three months.7.The phylogenetic tree of three gene regions in three time point samples of each infant showed that the 30 predominant species were scattered in each sample,and there was no significant relationship between the virus quasispecies.Conclusions1.The prevalence of HIV-1 infection among pregnant mothers who have not used any antiviral drugs before or during labor is higher than the national level.The implementation of infant blocking measures will reduce the exposure of newborns.2.HIV-1 DNA contains more information about the virus quasispecies than RNA,and traceability analysis using whole blood samples is more advantageous.3.Three intrauterine infection neonates infected with mothers'most dominant species,and the bottleneck effect was not obvious.4.Single drug is more likely to produce secondary drug resistance mutations than triple drug,especially resistance mutations against NNRTIs.5.Compared with the single drug regimen,triple drug can effectively inhibit the replication and mutation rate of the virus and reduce the distribution of virus quasispecies.6.Because the evolution range of virus variation is small,so it can't be used to judge the spread of predominant species through phylogenetic tree in the three time point samples of infant.7.In the HIV-1 three gene region?POL,GAG and ENV?,the variation degree in ENV is the largest.