Targeting CCR5 as a Component of an HIV-1 Therapeutic Strategy

Interventions during Early Infection: Opening a Window for an HIV Cure?

Although combination antiretroviral therapy (ART) has been a landmark achievement for the treatment of human immunodeficiency virus (HIV), an HIV cure has remained elusive. Elimination of latent HIV reservoirs that persist throughout HIV infection is the most challenging barrier to an HIV cure. The progressive HIV infection is marked by the increasing size and diversity of latent HIV reservoirs until an effective immune response is mobilized, which can control but not eliminate HIV infection. The stalemate between HIV replication and the immune response is manifested by the establishment of a viral set point. ART initiation during the early stage limits HIV reservoir development, preserves immune function, improves the quality of life, and may lead to ART-free viral remission in a few people living with HIV (PLWH). However, for the overwhelming majority of PLWH, early ART initiation alone does not cure HIV, and lifelong ART is needed to sustain viral suppression. A critical area of research is focused on determining whether HIV could be functionally cured if additional treatments are provided alongside early ART. Several HIV interventions including Block and Lock, Shock and Kill, broadly neutralizing antibody (bNAb) therapy, adoptive CD8+ T cell therapy, and gene therapy have demonstrated delayed viral rebound and/or viral remission in animal models and/or some PLWH. Whether or not their application during early infection can improve the success of HIV remission is less studied. Herein, we review the current state of clinical and investigative HIV interventions and discuss their potential to improve the likelihood of post-treatment remission if initiated during early infection.

Viral Factors in Modulation of Host Immune Response: A Route to Novel Antiviral Agents and New Therapeutic Approaches

Viruses utilize host cells at all stages of their life cycle, from the transcription of genes and translation of viral proteins to the release of viral copies. The human immune system counteracts viruses through a variety of complex mechanisms, including both innate and adaptive components. Viruses have an ability to evade different components of the immune system and affect them, leading to disruption. This review covers contemporary knowledge about the virus-induced complex interplay of molecular interactions, including regulation of transcription and translation in host cells resulting in the modulation of immune system functions. Thorough investigation of molecular mechanisms and signaling pathways that are involved in modulating of host immune response to viral infections can help to develop novel approaches for antiviral therapy. In this review, we consider new therapeutic approaches for antiviral treatment. Modern therapeutic strategies for the treatment and cure of human immunodeficiency virus (HIV) are considered in detail because HIV is a unique example of a virus that leads to host T lymphocyte deregulation and significant modulation of the host immune response. Furthermore, peculiarities of some promising novel agents for the treatment of various viral infections are described.

Development of a Sensitive Anti-Mouse CCR5 Monoclonal Antibody for Flow Cytometry

C-C chemokine receptor 5 (CCR5), a member of the G protein-coupled receptor family, is the most common coreceptor for the human immunodeficiency virus type 1. CCR5 is also involved in the pathogenesis of tumors and inflammatory diseases. The CCR5 antagonists including monoclonal antibodies (mAbs) have been developed and evaluated in clinical trials. In this study, we developed novel mAbs for mouse CCR5 (mCCR5) using the Cell-Based Immunization and Screening (CBIS) method. One of the established anti-mCCR5 mAbs, C5Mab-2 (rat IgG2b, kappa), reacted with mCCR5-overexpressed Chinese hamster ovary-K1 (CHO/mCCR5) and an endogenously mCCR5-expressing cell line (L1210) by flow cytometry. Using flow cytometry, the dissociation constant (KD) of C5Mab-2 for CHO/mCCR5 was determined as 4.3 × 10-8 M. These results indicated that C5Mab-2 is useful for the detection of mCCR5 in flow cytometry and may be applicable to obtain the proof of concept in preclinical studies.

Development of Sensitive Anti-Mouse CCR5 Monoclonal Antibodies Using the N-Terminal Peptide Immunization

One of the G protein-coupled receptors, C-C chemokine receptor 5 (CCR5), is an important regulator for the activation of T and B lymphocytes, dendritic cells, natural killer cells, and macrophages. Upon binding to its ligands, CCR5 activates downstream signaling, which is an important regulator in the innate and adaptive immune response through the promotion of lymphocyte migration and the secretion of proinflammatory cytokines. Anti-CCR5 monoclonal antibodies (mAbs) have been developed and evaluated in clinical trials for tumors and inflammatory diseases. In this study, we developed novel mAbs for mouse CCR5 (mCCR5) using the N-terminal peptide immunization. Among the established anti-mCCR5 mAbs, C5Mab-4 (rat IgG2a, kappa) and C5Mab-8 (rat IgG1, kappa), recognized mCCR5-overexpressing Chinese hamster ovary-K1 (CHO/mCCR5) and an endogenously mCCR5-expressing cell line (L1210) by flow cytometry. The dissociation constant (KD) values of C5Mab-4 and C5Mab-8 for CHO/mCCR5 were determined as 3.5 × 10-8 M and 7.3 × 10-9 M, respectively. Furthermore, both C5Mab-4 and C5Mab-8 could detect mCCR5 by western blotting. These results indicated that C5Mab-4 and C5Mab-8 are useful for detecting mCCR5 by flow cytometry and western blotting and provide a possibility to obtain the proof of concept in preclinical studies.

G protein-coupled receptor (GPCR) gene variants and human genetic disease

Genetic variations in the genes encoding G protein-coupled receptors (GPCRs) can disrupt receptor structure and function, which can result in human genetic diseases. Disease-causing mutations have been reported in at least 55 GPCRs for more than 66 monogenic diseases in humans. The spectrum of pathogenic and likely pathogenic variants includes loss of function variants that decrease receptor signaling on one extreme and gain of function that may result in biased signaling or constitutive activity, originally modeled on prototypical rhodopsin GPCR variants identified in retinitis pigmentosa, on the other. GPCR variants disrupt ligand binding, G protein coupling, accessory protein function, receptor desensitization and receptor recycling. Next generation sequencing has made it possible to identify variants of uncertain significance (VUS). We discuss variants in receptors known to result in disease and in silico strategies for disambiguation of VUS such as sorting intolerant from tolerant and polymorphism phenotyping. Modeling of variants has contributed to drug development and precision medicine, including drugs that target the melanocortin receptor in obesity and interventions that reverse loss of gonadotropin-releasing hormone receptor from the cell surface in idiopathic hypogonadotropic hypogonadism. Activating and inactivating variants of the calcium sensing receptor (CaSR) gene that are pathogenic in familial hypocalciuric hypercalcemia and autosomal dominant hypocalcemia have enabled the development of calcimimetics and calcilytics. Next generation sequencing has continued to identify variants in GPCR genes, including orphan receptors, that contribute to human phenotypes and may have therapeutic potential. Variants of the CaSR gene, some encoding an arginine-rich region that promotes receptor phosphorylation and intracellular retention, have been linked to an idiopathic epilepsy syndrome. Agnostic strategies have identified variants of the pyroglutamylated RF amide peptide receptor gene in intellectual disability and G protein-coupled receptor 39 identified in psoriatic arthropathy. Coding variants of the G protein-coupled receptor L1 (GPR37L1) orphan receptor gene have been identified in a rare familial progressive myoclonus epilepsy. The study of the role of GPCR variants in monogenic, Mendelian phenotypes has provided the basis of modeling the significance of more common variants of pharmacogenetic significance.

CB-0821, a novel CC chemokine receptor 5 (CCR5) inhibitor with improved binding efficacy proposed as anti-HIV candidate: Computational and in vitro approach

The CC chemokine receptor 5 (CCR5) serves a pivotal role in human immunodeficiency virus 1 (HIV-1) infection by acting as a co-receptor and facilitating the binding of the viral envelope glycoprotein (env). Maraviroc (MVC), a Food and Drug Administration-approved monocarboxylic acid amide, is one of the CCR5 inhibitors employed in HIV treatment. Despite the existence of approved drugs, the emergence of drug resistance underscores the necessity for novel compounds to combat resistance and enhance therapeutic efficacy. In this study, CB-0821, identified from the ChemBridge library, emerged as a promising CCR5 inhibitor. Molecular dynamics simulations indicate comparable dynamic properties for CB-0821 and MVC. In silico comparisons with other CCR5 inhibitors emphasize CB-0821's superior binding affinity, positioning it as a potential lead compound. Evaluations of the dissociation constant (Ki) and absorption, distribution, metabolism, and excretion predictions suggest CB-0821 as a well-tolerated drug. Furthermore, the dose-dependent inhibition of CCR5 by CB-0821 in Peripheral blood mononuclear cells (PBMCs) (ranging from 10 to 200 nM) demonstrates efficacy, coupled with nontoxicity to Vero cells at concentrations up to 500 nM. These results underscore the potential of CB-0821 in HIV antiviral therapy, calling for additional preclinical validations before advancing to clinical considerations.

Recent advances on anti-HIV chimeric antigen receptor-T-cell treatment to provide sustained HIV remission

PURPOSE OF REVIEW

Successful sustained remission of HIV infection has been achieved after CCR5Δ32/Δ32 allogeneic hematopoietic stem cell transplantation for treatment of leukemia in a small cohort of people living with HIV (PLWH). This breakthrough demonstrated that the goal of curing HIV was achievable. However, the high morbidity and mortality associated with bone marrow transplantation limits the routine application of this approach and provides a strong rationale for pursuing alternative strategies for sustained long-term antiretroviral therapy (ART)-free HIV remission. Notably, long-term immune-mediated control of HIV replication observed in elite controllers and posttreatment controllers suggests that potent HIV-specific immune responses could provide sustained ART-free remission in PLWH. The capacity of chimeric antigen receptor (CAR)-T cells engineered to target malignant cells to induce remission and cure in cancer patients made this an attractive approach to provide PLWH with a potent HIV-specific immune response. Here, we review the recent advances in the design and application of anti-HIV CAR-T-cell therapy to provide a functional HIV cure.

RECENT FINDINGS

HIV reservoirs are established days after infection and persist through clonal expansion of infected cells. The continuous interaction between latently infected cells and the immune system shapes the landscape of HIV latency and likely contributes to ART-free viral control in elite controllers. CAR-T cells can exhibit superior antiviral activity as compared with native HIV-specific T cells, particularly because they can be engineered to have multiple HIV specificities, resistance to HIV infection, dual costimulatory signaling, immune checkpoint inhibitors, stem cell derivation, CMV TCR coexpression, and tissue homing ligands. These modifications can significantly improve the capacities of anti-HIV CAR-T cells to prevent viral escape, resist HIV infection, and enhance cytotoxicity, persistence, and tissue penetration. Collectively, these novel modifications of anti-HIV CAR-T cell design have increased their capacity to control HIV infection.

SUMMARY

Anti-HIV CAR-T cells can be engineered to provide potent and sustained in-vitro and in-vivo antiviral function. The combination of anti-HIV CAR-T cells with other immunotherapeutics may contribute to long-term HIV remission in PLWH.

Combating antimicrobial resistance in malaria, HIV and tuberculosis

Antimicrobial resistance poses a significant threat to the sustainability of effective treatments against the three most prevalent infectious diseases: malaria, human immunodeficiency virus (HIV) infection and tuberculosis. Therefore, there is an urgent need to develop novel drugs and treatment protocols capable of reducing the emergence of resistance and combating it when it does occur. In this Review, we present an overview of the status and underlying molecular mechanisms of drug resistance in these three diseases. We also discuss current strategies to address resistance during the research and development of next-generation therapies. These strategies vary depending on the infectious agent and the array of resistance mechanisms involved. Furthermore, we explore the potential for cross-fertilization of knowledge and technology among these diseases to create innovative approaches for minimizing drug resistance and advancing the discovery and development of new anti-infective treatments. In conclusion, we advocate for the implementation of well-defined strategies to effectively mitigate and manage resistance in all interventions against infectious diseases.

Thermodynamic and molecular dynamic insights into how fusion influences peptide-tag recognition of an antibody

To understand the effect of protein fusion on the recognition of a peptide-tag by an antibody, we fused a CCR5-derived peptide-tag (pep1) to GFP and investigated its recognition by an anti-pep1 antibody, 4B08. First, to characterize the thermodynamic properties associated with the pep1-4B08 binding, isothermal titration calorimetry experiments were conducted. It was found that pep1 fused to the C-terminus of GFP (GFP-CT) enhanced the enthalpic gain by 2.1 kcal mol-1 and the entropic loss only by 0.9 kcal mol-1, resulting in an 8-fold increase in the binding affinity compared to the unfused pep1. On the other hand, pep1 fused to the N-terminus of GFP (GFP-NT) enhanced the enthalpic gain by 3.0 kcal mol-1 and the entropic loss by 3.2 kcal mol-1, leading to no significant enhancement of the binding affinity. To gain deeper insights, molecular dynamics simulations of GFP-NT, GFP-CT, and pep1 were performed. The results showed that the location of the fusion point sensitively affects the interaction energy, the solvent accessible surface area, and the fluctuation of pep1 in the unbound state, which explains the difference in the experimental thermodynamic properties.

HIV cure: Are we going to make history?

BACKGROUND

At present, combination antiretroviral therapy (cART) is the mainstay for the treatment of people living with HIV/AIDS. cART can suppress the viral load to a minimal level; however, the possibility of the emergence of full-blown AIDS is always there. In the latter part of the first decade of the 21st century, an HIV-positive person received stem cell transplantation (SCT) for treatment of his haematological malignancy. The patient was able to achieve remission of the haematological condition as well as of HIV following SCT. Thorough investigations of various samples including blood and biopsy could not detect the virus in the person's body. The person was declared to be the first cured case of HIV.

LITERATURE SEARCH

Over the next decade, a few more similar cases were observed and have recently been declared cured of the infection. A comprehensive search was performed in PubMed, Cochrane library and Google Scholar. Four such additional cases were found in literature.

DESCRIPTION & DISCUSSION

These cases all share a common proposed mechanism for the HIV cure, that is, transplantation of stem cells from donors carrying a homozygous mutation in a gene encoding for CCR5 (receptor utilized by HIV for entry into the host cell), denoted as CCR5△32. This mutation makes the host immune cells devoid of CCR5, causing the host to acquire resistance against HIV. To the best of our knowledge, this is the first review to look at relevant and updated information of all cured cases of HIV as well as the related landmarks in history and discusses the underlying mechanism(s).

A new age of precision gene therapy

Gene therapy has become a clinical reality as market-approved advanced therapy medicinal products for the treatment of distinct monogenetic diseases and B-cell malignancies. This Therapeutic Review aims to explain how progress in genome editing technologies offers the possibility to expand both therapeutic options and the types of diseases that will become treatable. To frame these impressive advances in the context of modern medicine, we incorporate examples from human clinical trials into our discussion on how genome editing will complement currently available strategies in gene therapy, which still mainly rely on gene addition strategies. Furthermore, safety considerations and ethical implications, including the issue of accessibility, are addressed as these crucial parameters will define the impact that gene therapy in general and genome editing in particular will have on how we treat patients in the near future.

Design methods for antimicrobial peptides with improved performance

The recalcitrance of pathogens to traditional antibiotics has made treating and eradicating bacterial infections more difficult. In this regard, developing new antimicrobial agents to combat antibiotic-resistant strains has become a top priority. Antimicrobial peptides (AMPs), a ubiquitous class of naturally occurring compounds with broad-spectrum antipathogenic activity, hold significant promise as an effective solution to the current antimicrobial resistance (AMR) crisis. Several AMPs have been identified and evaluated for their therapeutic application, with many already in the drug development pipeline. Their distinct properties, such as high target specificity, potency, and ability to bypass microbial resistance mechanisms, make AMPs a promising alternative to traditional antibiotics. Nonetheless, several challenges, such as high toxicity, lability to proteolytic degradation, low stability, poor pharmacokinetics, and high production costs, continue to hamper their clinical applicability. Therefore, recent research has focused on optimizing the properties of AMPs to improve their performance. By understanding the physicochemical properties of AMPs that correspond to their activity, such as amphipathicity, hydrophobicity, structural conformation, amino acid distribution, and composition, researchers can design AMPs with desired and improved performance. In this review, we highlight some of the key strategies used to optimize the performance of AMPs, including rational design and de novo synthesis. We also discuss the growing role of predictive computational tools, utilizing artificial intelligence and machine learning, in the design and synthesis of highly efficacious lead drug candidates.

Recent Progress in Synthesis, POM Analyses and SAR of Coumarin-Hybrids as Potential Anti-HIV Agents-A Mini Review

The human immunodeficiency virus (HIV) is the primary cause of acquired immune deficiency syndrome (AIDS), one of the deadliest pandemic diseases. Various mechanisms and procedures have been pursued to synthesise several anti-HIV agents, but due to the severe side effects and multidrug resistance spawning from the treatment of HIV/AIDS using highly active retroviral therapy (HAART), it has become imperative to design and synthesise novel anti-HIV agents. Literature has shown that natural sources, particularly the plant kingdom, can release important metabolites that have several biological, mechanistic and structural representations similar to chemically synthesised compounds. Certainly, compounds from natural and ethnomedicinal sources have proven to be effective in the management of HIV/AIDS with low toxicity, fewer side effects and affordability. From plants, fungi and bacteria, coumarin can be obtained, which is a secondary metabolite and is well known for its actions in different stages of the HIV replication cycle: protease, integrase and reverse transcriptase (RT) inhibition, cell membrane fusion and viral host attachment. These, among other reasons, are why coumarin moieties will be the basis of a good building block for the development of potent anti-HIV agents. This review aims to outline the synthetic pathways, structure-activity relationship (SAR) and POM analyses of coumarin hybrids with anti-HIV activity, detailing articles published between 2000 and 2023.

Biomedical generative pre-trained based transformer language model for age-related disease target discovery

Target discovery is crucial for the development of innovative therapeutics and diagnostics. However, current approaches often face limitations in efficiency, specificity, and scalability, necessitating the exploration of novel strategies for identifying and validating disease-relevant targets. Advances in natural language processing have provided new avenues for predicting potential therapeutic targets for various diseases. Here, we present a novel approach for predicting therapeutic targets using a large language model (LLM). We trained a domain-specific BioGPT model on a large corpus of biomedical literature consisting of grant text and developed a pipeline for generating target prediction. Our study demonstrates that pre-training of the LLM model with task-specific texts improves its performance. Applying the developed pipeline, we retrieved prospective aging and age-related disease targets and showed that these proteins are in correspondence with the database data. Moreover, we propose CCR5 and PTH as potential novel dual-purpose anti-aging and disease targets which were not previously identified as age-related but were highly ranked in our approach. Overall, our work highlights the high potential of transformer models in novel target prediction and provides a roadmap for future integration of AI approaches for addressing the intricate challenges presented in the biomedical field.

When Bacteria and Viruses Collide: A Tale of Chlamydia trachomatis and Sexually Transmitted Viruses

The global incidence of sexually transmitted infections (STIs) remains high, with the World Health Organization (WHO) estimating that over 1 million people acquire STIs daily. STIs can lead to infertility, pregnancy complications, and cancers. Co-infections with multiple pathogens are prevalent among individuals with an STI and can lead to heightened infectivity and more severe clinical manifestations. Chlamydia trachomatis (CT) is the most reported bacterial STI worldwide in both men and women, and several studies have demonstrated co-infection of CT with viral and other bacterial STIs. CT is a gram-negative bacterium with a unique biphasic developmental cycle including infectious extracellular elementary bodies (EBs) and metabolically active intracellular reticulate bodies (RBs). The intracellular form of this organism, RBs, has evolved mechanisms to persist for long periods within host epithelial cells in a viable but non-cultivable state. The co-infections of CT with the most frequently reported sexually transmitted viruses: human immunodeficiency virus (HIV), human papillomavirus (HPV), and herpes simplex virus (HSV) have been investigated through in vitro and in vivo studies. These research studies have made significant strides in unraveling the intricate interactions between CT, these viral STIs, and their eukaryotic host. In this review, we present an overview of the epidemiology of these co-infections, while specifically delineating the underlying mechanisms by which CT influences the transmission and infection dynamics of HIV and HSV. Furthermore, we explore the intricate relationship between CT and HPV infection, with a particular emphasis on the heightened risk of cervical cancer. By consolidating the current body of knowledge, we provide valuable insights into the complex dynamics and implications of co-infection involving CT and sexually transmitted viruses.

Genetically engineered neural stem cells (NSCs) therapy for neurological diseases; state-of-the-art

Neural stem cells (NSCs) are multipotent stem cells with remarkable self-renewal potential and also unique competencies to differentiate into neurons, astrocytes, and oligodendrocytes (ODCs) and improve the cellular microenvironment. In addition, NSCs secret diversity of mediators, including neurotrophic factors (e.g., BDNF, NGF, GDNF, CNTF, and NT-3), pro-angiogenic mediators (e.g., FGF-2 and VEGF), and anti-inflammatory biomolecules. Thereby, NSCs transplantation has become a reasonable and effective treatment for various neurodegenerative disorders by their capacity to induce neurogenesis and vasculogenesis and dampen neuroinflammation and oxidative stress. Nonetheless, various drawbacks such as lower migration and survival and less differential capacity to a particular cell lineage concerning the disease pathogenesis hinder their application. Thus, genetic engineering of NSCs before transplantation is recently regarded as an innovative strategy to bypass these hurdles. Indeed, genetically modified NSCs could bring about more favored therapeutic influences post-transplantation in vivo, making them an excellent option for neurological disease therapy. This review for the first time offers a comprehensive review of the therapeutic capability of genetically modified NSCs rather than naïve NSCs in neurological disease beyond brain tumors and sheds light on the recent progress and prospect in this context.

Evaluation of the Elements of Short Hairpin RNAs in Developing shRNA-Containing CAR T Cells

Short hairpin RNAs (shRNAs) have emerged as a powerful tool for gene knockdown in various cellular systems, including chimeric antigen receptor (CAR) T cells. However, the elements of shRNAs that are crucial for their efficacy in developing shRNA-containing CAR T cells remain unclear. In this study, we evaluated the impact of different shRNA elements, including promoter strength, orientation, multiple shRNAs, self-targeting, and sense and antisense sequence composition on the knockdown efficiency of the target gene in CAR T cells. Our findings highlight the importance of considering multiple shRNAs and their orientation to achieve effective knockdown. Moreover, we demonstrate that using a strong promoter and avoiding self-targeting can enhance CAR T cell functionality. These results provide a framework for the rational design of CAR T cells with shRNA-mediated knockdown capabilities, which could improve the therapeutic efficacy of CAR T cell-based immunotherapy.

Comparative Evaluation of the Activity of Various Lentiviral Vectors Containing Three Anti-HIV Genes

A promising direction in the treatment of HIV infection is a gene therapy approach based on the insertion of antiviral genes aimed at inhibiting HIV replication into the genome of host cells. We obtained six constructs of lentiviral vectors with different arrangements of three antiviral genes: microRNAs against the CCR5 gene, the gene encoding the C-peptide, and the gene encoding the modified human TRIM5a protein. We found that despite containing the same genes, these vectors were produced at different titers and had different effects on cell viability, transduction efficiency, and expression stability. Comparative evaluation of the antiviral activity of three of the six developed vectors that showed stable expression was carried out using the continuous SupT1 lymphocytic cell line. All of the vectors protected cells from HIV infection: the viral load was several orders of magnitude lower than in control cells, and with one vector, complete cessation of virus growth in modified cells was achieved.

Assessment of anti-HIV-1 guide RNA efficacy in cells containing the viral target sequence, corresponding gRNA, and CRISPR/Cas9

The Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas9 gene editing system has been shown to be effective at inhibiting human immunodeficiency virus type 1 (HIV-1). Studies have not consistently used a trackable dual reporter system to determine what cells received the Cas9/gRNA to determine the overall knockdown of HIV. Some studies have used stably transduced cells under drug selection to accomplish this goal. Here a two-color system was used that allows tracking of viral protein expression and which cells received the CRISPR/Cas9 system. These experiments ensured that each gRNA used was a perfect match to the intended target to remove this variable. The data showed that gRNAs targeting the transactivation response element (TAR) region or other highly conserved regions of the HIV-1 genome were effective at stopping viral gene expression, with multiple assays demonstrating greater than 95 percent reduction. Conversely, gRNAs targeting conserved sites of the 5' portion of the U3 region were largely ineffective, demonstrating that the location of edits in the long terminal repeat (LTR) matter with respect to function. In addition, it was observed that a gRNA targeting Tat was effective in a T-cell model of HIV-1 latency. Taken together, these studies demonstrated gRNAs designed to highly conserved functional regions have near 100% efficacy in vitro in cells known to have received the Cas9/gRNA pair.

Monoclonal CCR5 Antibody: A Promising Therapy for HIV

HIV is one of the world's most devastating viral infections and has claimed tens of millions of lives worldwide since it was first identified in the 1980s. There is no cure for HIV infection. However, with tremendous progress in HIV diagnosis, prevention, and treatment, HIV has become a manageable chronic health disease. CCR5 is an important coreceptor used by HIV to infect target cells, and genetic deficiency of the chemokine receptor CCR5 confers a significant degree of protection against HIV infection. In addition, since CCR5 deficiency does not appear to cause any adverse health effects, targeting this coreceptor is a promising strategy for the treatment and prevention of HIV. Monoclonal antibodies are frequently used as therapeutics for many diseases and therefore are being used as a potential therapy for HIV-1 infection. This review reports on CCR5 antibody research in detail and describes the role and advantages of CCR5 antibodies in HIV prevention or treatment, introduces several main CCR5 antibodies, and discusses the future strategy of antibody-conjugated nanoparticles including the potential challenges. CCR5 antibodies may be a novel therapy for treating HIV infection effectively and could overcome the limitations of the currently available options.

Plasma interleukin-7 correlation with human immunodeficiency virus RNA and CD4+ T cell counts, and interleukin-5 with circulating hepatitis B virus DNA may have implications in viral control

Chronic viral infections represent a leading cause of global morbidity and mortality. Chronic HBV, HCV, and HIV infections result in cytokine perturbations that may hold key implications in understanding the complex disease mechanisms driving virus persistence and/or resolution. Here, we determined the levels of various plasma cytokines using a commercial Bio-Plex Luminex cytokine array in chronic HBV (n = 30), HCV (n = 15), and HIV (n = 40) infections and correlated with corresponding plasma viral loads (PVLs) and liver parameters. We observed differential perturbations in cytokine profiles among the study groups. The cytokines levels positively correlated with PVL and liver transaminases. The monocyte-derived cytokines viz., MIP-1β, IL-8, and TNF-α, and Th2 cytokines like IL-4, IL-5, and IL-13 showed a better correlation with liver enzymes as compared to their corresponding PVLs. Our investigation also identified two cytokines viz., IL-5 and IL-7 that inversely correlated with HBV DNA and HIV PVLs, respectively. Regression analysis adjusted for age showed that every increase of IL-5 by one unit was associated with a reduction in HBV PVL by log10 0.4, whereas, every elevation by a unit of IL-7 was associated with decreased HIV PVL by log10 2.5. We also found that IL-7 levels correlated positively with absolute CD4+ T cell counts in HIV-infected patients. We concluded that plasma IL-5 and IL-7 may likely have a key role on viral control in HBV and HIV infections, respectively. A noteworthy increase in cytokines appears to bear protective and pathological significance, and indeed is reflective of the host's versatile immune armory against viral persistence.

Rational Engineering of a Sub-Picomolar HIV-1 Blocker

With the aim of rationally devising a refined and potent HIV-1 blocker, the cDNA of CCL5 5p12 5m, an extremely potent CCR5 antagonist, was fused to that of C37, a gp41-targeted fusion inhibitor. The resulting CCL5 5p12 5m-C37 fusion protein was expressed in E. coli and proved to be capable of inhibiting R5 HIV-1 strains with low to sub-picomolar IC₅₀, maintaining its antagonism toward CCR5. In addition, CCL5 5p12 5m-C37 inhibits R5/X4 and X4 HIV-1 strains in the picomolar concentration range. The combination of CCL5 5p12 5m-C37 with tenofovir (TDF) exhibited a synergic effect, promoting this antiviral cocktail. Interestingly, a CCR5-targeted combination of maraviroc (MVC) with CCL5 5p12 5m-C37 led to a synergic effect that could be explained by an extensive engagement of different CCR5 conformational populations. Within the mechanism of HIV-1 entry, the CCL5 5p12 5m-C37 chimera may fit as a powerful blocker in several instances. In its possible consideration for systemic therapy or pre-exposure prophylaxis, this protein design represents an interesting lead in the combat of HIV-1 infection.

Punica granatum as Anticandidal and Anti-HIV Agent: An HIV Oral Cavity Potential Drug

The oral cavity is crucial from diagnosis to adherence to HAART therapy in the HIV/AIDS population; consequently, drugs that can maintain healthy conditions in the oral cavity are necessary for patients with HIV/AIDS. Punica granatum (pomegranate) is a tree that has been employed extensively for centuries in the traditional medicine of ancient cultures for the treatment of a wide range of diseases, including oral and dental diseases. In recent decades, its potent anticandidal properties have been shown, especially on Candida albicans, the cause of the most common clinical manifestation in HIV patients. The present work contributes to the review of the anti-HIV and anticandidal properties of the plant species P. granatum as involved with the oral cavity. The literature reviewed revealed that crude extracts of pomegranate and its main isolated compounds possess inhibitory activity on different HIV targets, including binding viral proteins and the three replicative HIV enzymes. In addition, in the literature reviewed, pomegranate exhibited anticandidal effects on 10 different species. Thus, pomegranate appears to be an excellent candidate to explore and incorporate into the treatment of the oral cavity of HIV/AIDS patients, in that, in addition to its pharmacological effects such as antiviral and anticandidal, pomegranate represents an easily available, inexpensive, and safe natural source.

Does Sickle Cell Disease Protect against HIV Infection: A Systematic Review

OBJECTIVE

The aim of this systematic review was to investigate whether sickle cell disease (SCD) protects against human immunodeficiency virus (HIV) infection by determining the association between SCD and the incidence and virulence of HIV infection.

METHODS

This is a systematic review that used MEDLINE, PubMed, CINAHL, and Academic Search Complete as data sources. Articles describing the relationship of SCD with HIV infection were included in this review. The effect measures were converted to correlation coefficients and synthesized accordingly to examine the putative protective role of SCD against HIV infection. Independent full-text screening and data extraction were conducted on all eligible studies. The risk of bias was assessed using the mixed methods appraisal tool. We employed a random-effects model of meta-analysis to estimate the pooled prevalence. We computed Cochrane's Q statistics, I2, and prediction interval to quantify effect size heterogeneity.

RESULTS

SCD reduces the risk of HIV infection by 75% (odds ratio [OR] = 0.25; r = -0.36, p < 0.001; I2 = 71.65). There was no publication bias (Egger's t value = 0.411; p = 0.721). Similarly, risk of HIV virulence was reduced by 77% (OR = 0.23; r = -0.38; p < 0.001; I2 = 63.07). The mechanisms implicated in the protective influence of SCD include autosplenectomy, reduced CCR5 expression, and increased expression of heme and iron-regulated genes.

CONCLUSIONS

SCD appears to protect against HIV infection and slows HIV progression.