ABSTRACT
Objective To explore the polymorphism of nef gene and conservation level of functionally important domains of nef as well as their influences on HIV-1 disease progression of HIV-1 B'infected individuals in northern China.Methods 30 long term nonprogressors(LTNPs)and 42 typical progressors (TPs)were selected.Provirus DNA was extracted from whole blood sample.The full nef gene was amplified by nested-PCR.PCR product was sequenced directly after purification.Phylogenetic analysis and amino acid sequence mutation was applied on nef sequences to explore the differences between LTNPs and TPs.Results At position 15,the S15R/K/N substitution was detected.The frequency of TPs(64.29%)wsa higher than LTNPs(33.33%,P<0.01,0R=3.60);R21K/E/H/I.Q,TPs and LTNPs mutation frequency was 59.52%and 93.33%(P<0.005,OR=0.11);At position 39,K39R/E/N was only detected in TPs(23.81%,P<0.005).Conclusion No significant deletion or defect associated with disease progression wsa detected in nef gene of HIV-1 B'.But it suggested that K/E/H/I/Q mutation at 21 st amino acid of nef associated the disease nonprogression.R/K/N at 15 th amino acid of nef and R/E/N mutation at 39th amino acid of nef associated the disease progression in.HIV-1 B'.All domaias of nef amino acids sequences were comparatively conservative.
ABSTRACT
Objective To study the amino acid mutations in neutralizing antibody 2F5 and 4E10 conserved epitopes ELDKWA and NWFDIT of HIV-1 membrane proximal external region(MPER)in 92 HIV-infected individuals and AIDS patients in China,and to provide a basis for the neutralizing antobodies immunotherapy and a design of vaccines. Methods Nest-PCR methods were used to amplity genes of the HIV-1 env gp41 region.The amplified fragments were sequenced by double-deoxygen terminal method and translated into amino acids for analysis.The mutations of 2F5 and 4E10 neutralizing epitopes were identified by comparison with the epitopes reference data in HIV-1 Sequence Database.Results There were mutations on both 2F5 and 4E10 neutralizing epitopes.2F5 conserved neutralizing epitopes major mutations tocused on E662A(14.1%),K665S(17.4%),A667K(16.3%),and 4E10 conserved neutralizing epltopes major mutations included N671S(13.0%),D674S(3.3%),T676S(16.3%).The mutation rates of 2F5 and 4E10 epitopes were significanfly different between CRF_B'C-clade and B'-clade(P<0.05).The mutata rates of CRF_B'C-clade were higher than that of CRFOI_AE-clade in 2F5 epitopes(P<0.05).The mutation rates of B'-clade in 4E10 eiptopes showed significant difference in slow progressors,HIV-infected individuals and AIDS patients,respectively(P<0.05).Conclusion The HIV-1 patients in China are demonstrated diversified mutations in 2F5 and 4E10 neutralizing epitopes.The mutation degrees of amlno acids in conserved neutralizing epitopes are different in different subtypes.There may be a correlation between neutralizing epitopes mutations of 4E10 with disease progression.