Polymorphisms in CCR5Δ32 and Risk of HIV-1 Infection in the Southeast of Caspian Sea, Iran

Prevalence of CCR5 Delta 32 Genetic Variant in the Turkmen Population of Golestan Province, Northeast of Iran

The 32 bp deletion in the chemokine receptor (C-C motif) 5 gene (CCR5Δ32) is a natural loss of function polymorphism that prevents the protein from locating on the cell surface. This genetic variation acts as a double-edge sword in the pathogenesis/defense mechanism of different health conditions, such as viral infections, autoimmune diseases, and cancers. Here, we evaluated the prevalence of the CCR5Δ32 polymorphism in the Turkmen population of Golestan province, northeast of Iran. Blood samples were collected from 400 randomly selected Turkmen populations (199 women and 201 men), and genomic DNA was extracted. Characterization of CCR5Δ32 genotypes was performed by PCR using primers flanking the 32-nucleotide deletion in the CCR5 gene. The amplified DNA fragments were visualized on 2% agarose gel electrophoresis with cybergreen staining under UV light. All individuals were of Turkmen ethnicity and lived in the Golestan province, northeast of Iran. The mean age of all participants was 35.46 years, with a 20-45 year range. All the studied subjects were healthy without any severe conditions such as autoimmune disease and viral infections. All individuals had no history of HIV infection. The PCR product visualization showed that all the samples are at the 330 bp size, which means the CCR5Δ32 allele was utterly absent from the study population. The presence of the CCR5Δ32 allele among Turkmens may be attributed to the admixture with European descent people. We conclude that the CCR5Δ32 polymorphism may be absent in the Iranian Turkmen population, and further studies with a large population are needed.

The Influence Between C-C Chemokine Receptor 5 Genetic Polymorphisms and the Type-1 Human Immunodeficiency Virus: A 20-Year Review

Acquired immune deficiency syndrome (AIDS) is an infectious disease caused by the types 1 and 2 human immunodeficiency virus (HIV-1 and HIV-2). Clinical outcomes in patients are highly varied and delineated by complex interactions between virus, host, and environment, such as with help of co-receptors, for example, the C-C chemokine receptor 5 (CCR5). This work aimed to describe the scientific evidence relating the influence of CCR5 polymorphisms in association studies for HIV-1 disease susceptibility, severity, and transmissibility. This is a systematic review of the literature on single nucleotide polymorphisms (SNPs) and the deletion [Insertion and Deletion (Indel)] Δ32 of CCR5. The search for articles was based on the ScienceDirect, PubMed, and Coordination for the Improvement of Higher Education Personnel (CAPES) databases for the period between 2001 and 2021. The final sample consisted of 32 articles. ^†SNP rs1799987 is one of the genetic polymorphisms most associated with the criteria of susceptibility and severity of HIV-1, having distinct consequences in genotypic, allelic, and clinical analysis in the variability of investigated populations. As for the transmission character of the disease, the G mutant allele of rs1799987 corresponds to the highest positive association. ^‡Furthermore, the results on Indel Δ32 corroborate the absence and rarity of this variant in some populations. Finally, mitigating the severity of cases, SNPs rs1799988 and rs1800023 obtained significant attribution in individuals in the studied populations. It is shown that the reported polymorphisms express significant influences for the evaluation of diagnostic, therapeutic, and prophylactic measures for HIV-1 having fundamental particularities in the molecular, genetic, and transcriptional aspects of CCR5.

Evaluation of CCR5-Δ32 mutation and HIV-1 surveillance drug-resistance mutations in peripheral blood mononuclear cells of long-term non progressors of HIV-1-infected individuals

Aim: This study aimed to evaluate chemokine receptor 5 delta 32 (CCR5-Δ32) mutation and HIV-1 surveillance drug-resistance mutations (SDRMs) in peripheral blood mononuclear cells of long-term non progressors (LTNPs) of HIV-1-infected individuals. Materials and methods: This research was performed on 197 treatment-naive HIV-1-infected patients. After follow-up, it was determined that 15 (7.6%) of these people were LTNPs. The PCR assay was performed to identify the CCR5 genotype and HIV-1 SDRMs. Results: One (6.7%) of the LTNPs was heterozygous (wt/Δ32) for the CCR5 delta 32 (CCR5Δ32). However, none of the individuals was homozygous for this mutation (Δ32/Δ32). Moreover, none of the LTNPs showed HIV-1 SDRMs. The CRF35-AD subtype was the most dominant subtype, with a percentage of 93.3%. Conclusion: Iranian elite controllers are negative for CCR5-delta 32 homozygous genotype and drug resistance against antiretroviral drugs.

Designer Nucleases: Gene-Editing Therapies using CCR5 as an Emerging Target in HIV

Acquired Immunodeficiency Syndrome (AIDS), caused by the Human Immunodeficiency Virus (HIV), is a life-threatening disorder that persists worldwide as a severe health problem. Since it was linked with the HIV attachment process, the Chemokine receptor, CCR5, has been at the development leading edge of several gene-based therapies. Given the shortcomings of the current antiretroviral treatment procedure and the non-availability of a licensed vaccine, the aptitude to modify complex genomes with Designer Nucleases has had a noteworthy impact on biotechnology. Over the last years, ZFN, TALEN and CRISPR/Cas9 gene-editing technology have appeared as a promising solution that mimics the naturally occurring CCR5/Δ32 mutation and permanently guarantees the absence of CCR5-expression on the surface of HIV target-cells, leading to a continuous resistance to the virus entry and, ultimately, proving that cellular immunization from infection could be, in fact, a conceivable therapeutic approach to finally achieve the long-awaited functional cure of HIV.

Evaluation of CCR5-Δ32 mutation among individuals with high risk behaviors, neonates born to HIV-1 infected mothers, HIV-1 infected individuals, and healthy people in an Iranian population

One of the important genetic factors related to resistance to HIV-1 infection is the presence of the C-C chemokine receptor type 5 delta 32 (CCR5-Δ32) homozygous genotype (Δ32/Δ32). The aim of this study was to evaluate the CCR5-Δ32 mutation among individuals with high-risk behaviors, neonates born to HIV-1-infected mothers in the prevention of mother-to-child transmission (PMTCT) project, HIV-1-infected individuals, and healthy people. The frequency of the CCR5-Δ32 genotype was assessed in a cross-sectional survey carried out from March 2014 to March 2019 among four different groups of the Iranian population. Genomic DNA was extracted from peripheral blood mononuclear cells of 140 Iranian healthy people, 84 neonates born to HIV-1-infected mothers in the PMTCT project, 71 people with high-risk behaviors, and 76 HIV-1-infected individuals. The polymerase chain reaction method was used for the amplification of the CCR5 gene. The CCR5-Δ32 heterozygous deletion was detected in five (6.6%) HIV-1-infected individuals, four (4.7%) neonates born to HIV-1 positive mothers, two (1.4%) healthy people, and also three (4.2%) people with high-risk behaviors whereas the CCR5-Δ32 homozygous deletion was absent in all the groups (Fisher's exact test, P = .0242). The allele of CCR5-Δ32 homozygous was not detected in the four study groups, and no significant difference was seen in the frequency of the CCR5Δ32 heterozygous allele between HIV seropositive and seronegative individuals. Therefore, it seems that this allele alone cannot explain the natural resistance to HIV-1 infection and probably several mechanisms are responsible for these processes and it should be further investigated.

Prevalence of CCR5delta32 in Northeastern Iran

Background

A 32-base pair deletion (∆32) in the open reading frame (ORF) of C-C motif chemokine receptor 5 (CCR5) seems to be a protective variant against immune system diseases, especially human immunodeficiency virus type 1 (HIV-1). We aimed to assess the frequency of CCR5∆32 in the healthy Iranian population.

Methods

In this study, 400 normal samples from Khorasan, northeastern Iran, were randomly selected. The frequency of CCR5∆32 carriers was investigated using PCR analysis. Allele prevalence and the fit to the Hardy-Weinberg equilibrium were analyzed.

Results

The prevalence of CCR5∆32 in the northeastern population of Iran was 0.016. Four hundred samples were studied, among which one with CCR5^∆32/∆32 and 11 with CCR5^Wild/∆32 genotype were detected.

Conclusion

This study was the first investigation for an assessment of the prevalence of CCR5∆32 in northeastern Iran. The low prevalence of CCR5∆32 allele in the Iranian population may result in the increased susceptibility to HIV-1. In addition, this prevalence is the same as that of reported in East Asia, while is lower than that in the Europeans.

The CCR5-Delta32 Genetic Polymorphism and HIV-1 Infection Susceptibility: a Meta-analysis

The CC chemokine receptor 5 (CCR5) is a chemokine receptor which is widely expressed in several immune cells involved in the inflammatory responses. Previous published studies revealed the relation of the CCR5 gene (CCR5-delta32) with the risk of HIV-1 infection, but the results are debatable and inconclusive. Here by meta-analysis, we have systematically evaluated the relation between the CCR5-delta32 polymorphism and the risk of HIV-1 infection. A comprehensive search in PubMed, EMBASE, CNKI, Cochrane Library, and WanFang database was performed up to April 15, 2018. The pooled odds ratio (ORs) along with its 95% credible interval (95%CI) was used to evaluate the relation between the CCR5-delta32 polymorphism and HIV-1 infection risk. The study included 24 case-control studies involving 4,786 HIV-1 infection patients and 6,283 controls. Compared with the wild-type homozygous genotypes, the results showed that the CCR5-delta32 heterozygotes (OR=1.16, 95%CI=1.02-1.32) had an increased susceptibility to HIV-1 and the delta32 homozygous (OR=0.25, 95%CI=0.09-0.68) had significantly reduced the susceptibility to HIV-1 for healthy controls. Moreover, we have found the delta32 allele carriers (OR=0.71, 95%CI=0.54-0.94) had significantly cut down the HIV-1 infection susceptibility when using exposed uninfected (EU) as controls. We also conducted the stratified analysis by ethnicity, and there significant association was detected in Caucasian in delta32 allele carrier genotype. To summarize, our meta-analysis suggests that the CCR5-delta32 homozygous genotype (delta32/delta32) confer possible protection against HIV-1, especially the exposed uninfected groups.