Association of a single nucleotide polymorphism in the ubxn6 gene with long-term non-progression phenotype in HIV-positive individuals

OBJECTIVES

The long-term non-progressors (LTNPs) are a heterogeneous group of HIV-positive individuals characterized by their ability to maintain high CD4⁺ T-cell counts and partially control viral replication for years in the absence of antiretroviral therapy. The present study aims to identify host single nucleotide polymorphisms (SNPs) associated with non-progression in a cohort of 352 individuals.

METHODS

DNA microarrays and exome sequencing were used for genotyping about 240 000 functional polymorphisms throughout more than 20 000 human genes. The allele frequencies of 85 LTNPs were compared with a control population. SNPs associated with LTNPs were confirmed in a population of typical progressors. Functional analyses in the affected gene were carried out through knockdown experiments in HeLa-P4, macrophages and dendritic cells.

RESULTS

Several SNPs located within the major histocompatibility complex region previously related to LTNPs were confirmed in this new cohort. The SNP rs1127888 (UBXN6) surpassed the statistical significance of these markers after Bonferroni correction (q = 2.11 × 10^-6). An uncommon allelic frequency of rs1127888 among LTNPs was confirmed by comparison with typical progressors and other publicly available populations. UBXN6 knockdown experiments caused an increase in CAV1 expression and its accumulation in the plasma membrane. In vitro infection of different cell types with HIV-1 replication-competent recombinant viruses caused a reduction of the viral replication capacity compared with their corresponding wild-type cells expressing UBXN6.

CONCLUSIONS

A higher prevalence of Ala31Thr in UBXN6 was found among LTNPs within its N-terminal region, which is crucial for UBXN6/VCP protein complex formation. UBXN6 knockdown affected CAV1 turnover and HIV-1 replication capacity.

[Human leukocyte antigen polymorphism of HIV infected persons without disease progress for long-term in Henan province, 2011-2016]

Objective: To understand the disease progression and human leukocyte antigen (HLA) gene polymorphism of HIV-infected persons without disease progress for long term, also known as long-term non-progressors (LTNPs), in Henan province. Methods: A retrospective study was conducted in 48 LTNPs with complete detection and follow-up information during 2011-2016 in Henan. Changes of CD(4)(+)T cells counts (CD(4)) and viral load (VL) during follow-up period were discussed. Polymerase chain reaction-sequence-specific oligonucleotide probe (PCR-SSOP) was used for the analyses of HLA-A, HLA-B and HLA-DRB1 alleles between LTNPs and healthy controls. Results: From 2011 to 2016, forty-eight LTNPs showed a decrease of the quartile (P(25)-P(75)) of CD(4) from 601.00 (488.50-708.72)/μl to 494.00 (367.00-672.00)/μl, and the difference was significant (P<0.05). The increase of the quartile (P(25)-P(75)) of log(10)VL from 3.40 (2.87-3.97) to 3.48 (2.60-4.37), but the difference was not significant (P>0.05). HLA polymorphism analysis revealed that HLA-B*13:02 and HLA-B*40:06 were more common in LTNPs (P<0.05), while HLA-B*46:01 and HLA-DRB1*09:01 were more common in healthy controls (P<0.05). Conclusions: The CD(4) of LTNPs in Henan showed a downward trend year by year. HLA-B*13:02 and B*40:06 might be associated with delayed disease progression for HIV infected persons in Henan.

[Characteristics of HIV-infected persons without long term disease progress and related factors in Guangxi Zhuang Autonomous Region]

Objective: To understand the characteristics of HIV infected persons without long term disease progress [also known as long term non-progressors (LTNPs)], and related factors in Guangxi Zhuang Autonomous Region (Guangxi). Methods: Data of persons living with HIV and receiving no antiretroviral therapy in Guangxi by the end of 2016 were collected from the national HIV/AIDS comprehensive control and prevention information system of China. Results: By the end of 2016, there were 313 LTNPs in Guangxi, accounting for 2.3% of those being reported for more than 10 years, 5.4% of those being reported for more than 10 years and surviving, and 26.6% of those being reported for more than 10 years, surviving and receiving no antiretroviral therapy. Among the LTNPs, 87.2%(273) were men, 94.9% (297) were aged ≤ 40 years, 32.3% (101) were farmers, 55.6% (174) were single, divorced or widowed, 69.3% (217) were of Han ethnic group, 68.1% (213) were injecting drug users, and 52.1% (163) were from custody facilities. Multiple logistic regression analysis indicated that factors associated with delayed disease progression included age ≤40 years (compared with age >40 years, aOR=1.55, 95%CI: 1.31-3.12) and injection drug use (compared with sexual transmission, aOR=1.23, 95%CI: 1.10-1.74). Conclusions: A number of LTNPs existed in HIV-infected individuals in Guangxi. Further research are needed to identify the related factors, and it is necessary to conduct large sample size studies on host immunology, genetics and the virology of HIV to explore the related mechanism.