The anti-apoptotic function of HSV-1 LAT in neuronal cell cultures but not its function during reactivation correlates with expression of two small non-coding RNAs, sncRNA1&2.

Multiple functions are associated with HSV-1 latency associated transcript (LAT), including establishment of latency, virus reactivation, and antiapoptotic activity. LAT encodes two sncRNAs that are not miRNAs and previously it was shown that they have antiapoptotic activity in vitro. To determine if we can separate the antiapoptotic function of LAT from its latency-reactivation function, we deleted sncRNA1 and sncRNA2 sequences in HSV-1 strain McKrae, creating ΔsncRNA1&2 recombinant virus. Deletion of the sncRNA1&2 in ΔsncRNA1&2 virus was confirmed by complete sequencing of ΔsncRNA1&2 virus and its parental virus. Replication of ΔsncRNA1&2 virus in tissue culture or in the eyes of WT infected mice was similar to that of HSV-1 strain McKrae (LAT-plus) and dLAT2903 (LAT-minus) viruses. The levels of gB DNA in trigeminal ganglia (TG) of mice latently infected with ΔsncRNA1&2 virus was intermediate to that of dLAT2903 and McKrae infected mice, while levels of LAT in TG of latently infected ΔsncRNA1&2 mice was significantly higher than in McKrae infected mice. Similarly, the levels of LAT expression in Neuro-2A cells infected with ΔsncRNA1&2 virus was significantly higher than in McKrae infected cells. Reactivation in TG of ΔsncRNA1&2 infected mice was similar to that of McKrae and time of reactivation in both groups were significantly faster than dLAT2903 infected mice. However, levels of apoptosis in Neuro-2A cells infected with ΔsncRNA1&2 virus was similar to that of dLAT2903 and significantly higher than that of McKrae infected cells. Our results suggest that the antiapoptotic function of LAT resides within the two sncRNAs, which works independently of its latency-reactivation function and it has suppressive effect on LAT expression in vivo and in vitro.

The histone methyltransferase SETD2 regulates HIV expression and latency.

Understanding the mechanisms that drive HIV expression and latency is a key goal for achieving an HIV cure. Here we investigate the role of the SETD2 histone methyltransferase, which deposits H3K36 trimethylation (H3K36me3), in HIV infection. We show that prevention of H3K36me3 by a potent and selective inhibitor of SETD2 (EPZ-719) leads to reduced post-integration viral gene expression and accelerated emergence of latently infected cells. CRISPR/Cas9-mediated knockout of SETD2 in primary CD4 T cells confirmed the role of SETD2 in HIV expression. Transcriptomic profiling of EPZ-719-exposed HIV-infected cells identified numerous pathways impacted by EPZ-719. Notably, depletion of H3K36me3 prior to infection did not prevent HIV integration but resulted in a shift of integration sites from highly transcribed genes to quiescent chromatin regions and to polycomb repressed regions. We also observed that SETD2 inhibition did not apparently affect HIV RNA levels, indicating a post-transcriptional mechanism affecting HIV expression. Viral RNA splicing was modestly reduced in the presence of EPZ-719. Intriguingly, EPZ-719 exposure enhanced responsiveness of latent HIV to the HDAC inhibitor vorinostat, suggesting that H3K36me3 can contribute to a repressive chromatin state at the HIV locus. These results identify SETD2 and H3K36me3 as novel regulators of HIV integration, expression and latency.

Monocyte to macrophage differentiation and changes in cellular redox homeostasis promote cell type-specific HIV latency reactivation.

HIV latency regulation in monocytes and macrophages can vary according to signals directing differentiation, polarization, and function. To investigate these processes, we generated an HIV latency model in THP-1 monocytes and showed differential levels of HIV reactivation among clonal populations. Monocyte-to-macrophage differentiation of HIV-infected primary human CD14+ and THP-1 cells induced HIV reactivation and showed that virus production increased concomitant with macrophage differentiation. We applied the HIV-infected THP-1 monocyte-to-macrophage (MLat) model to assess the biological mechanisms regulating HIV latency dynamics during monocyte-to-macrophage differentiation. We pinpointed protein kinase C signaling pathway activation and Cyclin T1 upregulation as inherent differentiation mechanisms that regulate HIV latency reactivation. Macrophage polarization regulated latency, revealing proinflammatory M1 macrophages suppressed HIV reactivation while anti-inflammatory M2 macrophages promoted HIV reactivation. Because macrophages rely on reactive-oxygen species (ROS) to exert numerous cellular functions, we disrupted redox pathways and found that inhibitors of the thioredoxin (Trx) system acted as latency-promoting agents in T-cells and monocytes, but opposingly acted as latency-reversing agents in macrophages. We explored this mechanism with Auranofin, a clinical candidate for reducing HIV reservoirs, and demonstrated Trx reductase inhibition led to ROS induced NF-κB activity, which promoted HIV reactivation in macrophages, but not in T-cells and monocytes. Collectively, cell type-specific differences in HIV latency regulation could pose a barrier to HIV eradication strategies.

Dynamic modulation of the non-canonical NF-κB signaling pathway for HIV shock and kill.

HIV cure still remains an elusive target. The "Shock and Kill" strategy which aims to reactivate HIV from latently infected cells and subsequently kill them through virally induced apoptosis or immune mediated clearance, is the subject of widespread investigation. NF-κB is a ubiquitous transcription factor which serves as a point of confluence for a number of intracellular signaling pathways and is also a crucial regulator of HIV transcription. Due to its relatively lower side effect profile and proven role in HIV transcription, the non-canonical NF-κB pathway has emerged as an attractive target for HIV reactivation, as a first step towards eradication. A comprehensive review examining this pathway in the setting of HIV and its potential utility to cure efforts is currently lacking. This review aims to summarize non-canonical NF-κB signaling and the importance of this pathway in HIV shock-and-kill efforts.

Humanized mice for studying HIV latency and potentially its eradication.

PURPOSE OF THE REVIEW: The quest for an HIV cure faces a formidable challenge: the persistent presence of latent viral infections within the cells and tissues of infected individuals. This review provides a thorough examination of discussions surrounding HIV latency, the use of humanized mouse models, and strategies aimed at eliminating the latent HIV reservoir. It explores the hurdles and advancements in understanding HIV pathogenesis, mainly focusing on establishing latent reservoirs in CD4 + T cells and macrophages. Introducing the concepts of functional and sterile cures, the review underscores the indispensable role of humanized mouse models in HIV research, offering crucial insights into the efficacy of cART and the ongoing pursuit of an HIV cure. RECENT FINDINGS: Here, we highlight studies investigating molecular mechanisms and pathogenesis related to HIV latency in humanized mice and discuss novel strategies for eradicating latent HIV. Emphasizing the importance of analytical cART interruption in humanized mouse studies to gauge its impact on the latent reservoir accurately, the review underlines the ongoing progress and challenges in harnessing humanized mouse models for HIV research. SUMMARY: This review suggests that humanized mice models provide valuable insights into HIV latency and potential eradication strategies, contributing significantly to the quest for an HIV cure.

The hypoxia-regulated ectonucleotidase CD73 is a host determinant of HIV latency.

Deciphering the mechanisms underlying viral persistence is critical to achieving a cure for human immunodeficiency virus (HIV) infection. Here, we implement a systems approach to discover molecular signatures of HIV latently infected CD4+ T cells, identifying the immunosuppressive, adenosine-producing ectonucleotidase CD73 as a key surface marker of latent cells. Hypoxic conditioning, reflecting the lymphoid tissue microenvironment, increases the frequency of CD73+ CD4+ T cells and promotes HIV latency. Transcriptomic profiles of CD73+ CD4+ T cells favor viral quiescence, immune evasion, and cell survival. CD73+ CD4+ T cells are capable of harboring a functional HIV reservoir and reinitiating productive infection ex vivo. CD73 or adenosine receptor blockade facilitates latent HIV reactivation in vitro, mechanistically linking adenosine signaling to viral quiescence. Finally, tissue imaging of lymph nodes from HIV-infected individuals on antiretroviral therapy reveals spatial association between CD73 expression and HIV persistence in vivo. Our findings warrant development of HIV-cure strategies targeting the hypoxia-CD73-adenosine axis.

Intermittent therapy with helicase-primase inhibitor IM-250 efficiently controls recurrent herpes disease and reduces reactivation of latent HSV.

Herpes is a contagious life-long infection with persistently high incidence and prevalence, causing significant disease worldwide. Current therapies have efficacy against active HSV infections but no impact on the latent viral reservoir in neurons. Thus, despite treatment, disease recurs from latency and the infectious potential remains unaffected within patients. Here, efficacy of the helicase-primase inhibitor (HPI) IM-250 against chronic neuronal HSV infections utilizing two classic herpes in vivo latency/reactivation animal models (intravaginal guinea pig HSV-2 infection model and ocular mouse HSV-1 infection model) is presented. Intermittent therapy of infected animals with 4-7 cycles of IM-250 during latency silences subsequent recurrences analyzed up to 6 months. In contrast to common experience, our studies show that the latent reservoir is indeed accessible to antiviral therapy altering the latent viral reservoir such that reactivation frequency can be reduced significantly by prior IM-250 treatment. We provide evidence that antiviral treatment during HSV latency can reduce future reactivation from the latent reservoir, supporting a conceptual shift in the antiviral field, and reframing what is achievable with respect to therapy of latent neuronal HSV infections.

Preexisting helminth challenge exacerbates infection and reactivation of gammaherpesvirus in tissue resident macrophages.

Even though gammaherpesvirus and parasitic infections are endemic in parts of the world, there is a lack of understanding about the outcome of coinfection. In humans, coinfections usually occur sequentially, with fluctuating order and timing in different hosts. However, experimental studies in mice generally do not address the variables of order and timing of coinfections. We sought to examine the variable of coinfection order in a system of gammaherpesvirus-helminth coinfection. Our previous work demonstrated that infection with the intestinal parasite, Heligmosomoides polygyrus, induced transient reactivation from latency of murine gammaherpesvirus-68 (MHV68). In this report, we reverse the order of coinfection, infecting with H. polygyrus first, followed by MHV68, and examined the effects of preexisting parasite infection on MHV68 acute and latent infection. We found that preexisting parasite infection increased the propensity of MHV68 to reactivate from latency. However, when we examined the mechanism for reactivation, we found that preexisting parasite infection increased the ability of MHV68 to reactivate in a vitamin A dependent manner, a distinct mechanism to what we found previously with parasite-induced reactivation after latency establishment. We determined that H. polygyrus infection increased both acute and latent MHV68 infection in a population of tissue resident macrophages, called large peritoneal macrophages. We demonstrate that this population of macrophages and vitamin A are required for increased acute and latent infection during parasite coinfection.

Binding of herpesvirus entry mediator (HVEM) and HSV-1 gD affect reactivation but not latency levels.

Previously we reported that the HSV-1 latency associated transcript (LAT) specifically upregulates the cellular herpesvirus entry mediator (HVEM) but no other known HSV-1 receptors. HSV-1 glycoprotein D (gD) binds to HVEM but the effect of this interaction on latency-reactivation is not known. We found that the levels of latent viral genomes were not affected by the absence of gD binding to HVEM. However, reactivation of latent virus in trigeminal ganglia explant cultures was blocked in the absence of gD binding to HVEM. Neither differential HSV-1 replication and spread in the eye nor levels of latency influenced reactivation. Despite similar levels of latency, reactivation in the absence of gD binding to HVEM correlated with reduced T cell exhaustion. Our results indicate that HVEM-gD signaling plays a significant role in HSV-1 reactivation but not in ocular virus replication or levels of latency. The results presented here identify gD binding to HVEM as an important target that influences reactivation and survival of ganglion resident T cells but not levels of latency. This concept may also apply to other herpesviruses that engages HVEM.

Bcl-xL is required to protect endothelial cells latently infected with KSHV from virus induced intrinsic apoptosis.

Kaposi's Sarcoma herpesvirus (KSHV) is the etiologic agent of Kaposi's Sarcoma (KS), a highly vascularized tumor common in AIDS patients and many countries in Africa. KSHV is predominantly in the latent state in the main KS tumor cell, the spindle cell, a cell expressing endothelial cell markers. To identify host genes important for KSHV latent infection of endothelial cells we previously used a global CRISPR/Cas9 screen to identify genes necessary for the survival or proliferation of latently infected cells. In this study we rescreened top hits and found that the highest scoring gene necessary for infected cell survival is the anti-apoptotic Bcl-2 family member Bcl-xL. Knockout of Bcl-xL or treatment with a Bcl-xL inhibitor leads to high levels of cell death in latently infected endothelial cells but not their mock counterparts. Cell death occurs through apoptosis as shown by increased PARP cleavage and activation of caspase-3/7. Knockout of the pro-apoptotic protein, Bax, eliminates the requirement for Bcl-xL. Interestingly, neither Bcl-2 nor Mcl-1, related and often redundant anti-apoptotic proteins of the Bcl-2 protein family, are necessary for the survival of latently infected endothelial cells, likely due to their lack of expression in all the endothelial cell types we have examined. Bcl-xL is not required for the survival of latently infected primary effusion lymphoma (PEL) cells or other cell types tested. Expression of the KSHV major latent locus alone in the absence of KSHV infection led to sensitivity to the absence of Bcl-xL, indicating that viral gene expression from the latent locus induces intrinsic apoptosis leading to the requirement for Bcl-xL in endothelial cells. The critical requirement of Bcl-xL during KSHV latency makes it an intriguing therapeutic target for KS tumors.

HIV Tissue Reservoirs: Current Advances in Research.

Acquired immunodeficiency syndrome (AIDS), caused by the human immunodeficiency virus (HIV), has become a heavy burden of disease and an important public health problem in the world. Although current antiretroviral therapy (ART) is effective at suppressing the virus in the blood, HIV still remains in two different types of reservoirs-the latently infected cells (represented by CD4+ T cells) and the tissues containing those cells, which may block access to ART, HIV-neutralizing antibodies and latency-reversing agents. The latter is the focus of our review, as blood viral load drops below detectable levels after ART, a deeper and more systematic understanding of the HIV tissue reservoirs is imperative. In this review, we take the lymphoid system (including lymph nodes, gut-associated lymphoid tissue, spleen and bone marrow), nervous system, respiratory system, reproductive system (divided into male and female), urinary system as the order, focusing on the particularity and importance of each tissue in HIV infection, the infection target cell types of each tissue, the specific infection situation of each tissue quantified by HIV DNA or HIV RNA and the evidence of compartmentalization and pharmacokinetics. In summary, we found that the present state of HIV in different tissues has both similarities and differences. In the future, the therapeutic principle we need to follow is to respect the discrepancy on the basis of grasping the commonality. The measures taken to completely eliminate the virus in the whole body cannot be generalized. It is necessary to formulate personalized treatment strategies according to the different characteristics of the HIV in the various tissues, so as to realize the prospect of curing AIDS as soon as possible.

Wogonin inhibits latent HIV-1 reactivation by downregulating histone crotonylation.

BACKGROUND: Wogonin, a flavone isolated from Scutellaria baicalensis Georgi, is a commonly used phytochemical with anti-inflammatory and antitumor properties. However, the antiviral activity of wogonin against human immunodeficiency virus type 1 (HIV-1) has not been reported. PURPOSE: The current study aimed to explore whether wogonin can suppress latent HIV-1 reactivation and the mechanism of wogonin in inhibiting proviral HIV-1 transcription. METHODS: We assessed the effects of wogonin on HIV-1 reactivation using flow cytometry, cytotoxicity assay, quantitative PCR (qPCR), viral quality assurance (VQA), and western blot analysis. RESULTS: Wogonin, a flavone isolated from S. baicalensis, significantly inhibited the reactivation of latent HIV-1 in cellular models and in primary CD4+ T cells from antiretroviral therapy (ART)-suppressed individuals ex vivo. Wogonin exhibited low cytotoxicity and long-lasting inhibition of HIV-1 transcription. Triptolide is a latency-promoting agent (LPA) that inhibits HIV-1 transcription and replication; wogonin had a stronger ability to inhibit HIV-1 latent reactivation than triptolide. Mechanistically, wogonin inhibited the reactivation of latent HIV-1 by inhibiting the expression of p300, a histone acetyltransferase, and decreasing the crotonylation of histone H3/H4 in the HIV-1 promoter region. CONCLUSION: Our study found that wogonin is a novel LPA that can inhibit HIV-1 transcription by HIV-1 epigenetic silencing, which could bear promising significance for future applications of HIV-1 functional cure.

The Intersection of Innate Immune Pathways with the Latent Herpes Simplex Virus Genome.

Innate immune responses can impact different stages of viral life cycles. Herpes simplex virus latent infection of neurons and subsequent reactivation provide a unique context for immune responses to intersect with different stages of infection. Here, we discuss recent findings linking neuronal innate immune pathways with the modulation of latent infection, acting at the time of reactivation and during initial neuronal infection to have a long-term impact on the ability of the virus to reactivate.

Rethinking human cytomegalovirus latency reservoir.

Human cytomegalovirus (HCMV) is a prevalent herpesvirus, infecting the majority of the human population. Like other herpesviruses, it causes lifelong infection through the establishment of latency. Although reactivation from latency can cause significant morbidity and mortality in immunocompromised hosts, our understanding of HCMV latency and how it is maintained remains limited. Here, we discuss the characterized latency reservoir in hematopoietic cells in the bone marrow and the gaps in our knowledge of mechanisms that facilitate HCMV genome maintenance in dividing cells. We further review clinical evidence that strongly suggests the tissue origin of HCMV reactivation, and we outline similarities to murine cytomegalovirus where latency in tissue-resident cells has been demonstrated. Overall, we think these observations call for a rethinking of HCMV latency reservoirs and point to potential sources of HCMV latency that reside in tissues.

Deletion of the Transcriptional Coactivator HCF-1 In Vivo Impairs the Removal of Repressive Heterochromatin from Latent HSV Genomes and Suppresses the Initiation of Viral Reactivation.

Transcription of herpes simplex virus 1 (HSV-1) immediate early (IE) genes is controlled at multiple levels by the cellular transcriptional coactivator, HCF-1. HCF-1 is complexed with epigenetic factors that prevent silencing of the viral genome upon infection, transcription factors that drive initiation of IE gene expression, and transcription elongation factors required to circumvent RNAPII pausing at IE genes and promote productive IE mRNA synthesis. Significantly, the coactivator is also implicated in the control of viral reactivation from latency in sensory neurons based on studies that demonstrate that HCF-1-associated epigenetic and transcriptional elongation complexes are critical to initiate IE expression and viral reactivation. Here, an HCF-1 conditional knockout mouse model (HCF-1cKO) was derived to probe the role and significance of HCF-1 in the regulation of HSV-1 latency/reactivation in vivo. Upon deletion of HCF-1 in sensory neurons, there is a striking reduction in the number of latently infected neurons that initiate viral reactivation. Importantly, this correlated with a defect in the removal of repressive chromatin associated with latent viral genomes. These data demonstrate that HCF-1 is a critical regulatory factor that governs the initiation of HSV reactivation, in part, by promoting the transition of latent viral genomes from a repressed heterochromatic state. IMPORTANCE Herpes simplex virus is responsible for a substantial worldwide disease burden. An initial infection leads to the establishment of a lifelong persistent infection in sensory neurons. Periodic reactivation can result in recurrent oral and genital lesions to more significant ocular disease. Despite the significance of this pathogen, many of the regulatory factors and molecular mechanisms that govern the viral latency-reactivation cycles have yet to be elucidated. Initiation of both lytic infection and reactivation are dependent on the expression of the viral immediate early genes. In vivo deletion of a central component of the IE regulatory paradigm, the cellular transcriptional coactivator HCF-1, reduces the epigenetic transition of latent viral genomes, thus suppressing HSV reactivation. These observations define HCF-1 as a critical regulator that controls the initiation of HSV reactivation from latency in vivo and contribute to understanding of the molecular mechanisms that govern viral reactivation.

The CMV-encoded G protein-coupled receptors M33 and US28 play pleiotropic roles in immune evasion and alter host T cell responses.

Introduction: Human cytomegalovirus (HCMV) is a global health threat due to its ubiquity and lifelong persistence in infected people. During latency, host CD8+ T cell responses to HCMV continue to increase in a phenomenon known as memory inflation. We used murine CMV (MCMV) as a model for HCMV to characterize the memory inflation response to wild-type MCMV (KP) and a latency-defective mutant (ΔM33stop), which lacks M33, an MCMV chemokine receptor homolog. M33 is essential for normal reactivation from latency and this was leveraged to determine whether reactivation in vivo contributes to T cell memory inflation. Methods: Mice were infected with wild-type or mutant MCMV and T cell responses were analyzed by flow cytometry at acute and latent time points. Ex vivo reactivation and cytotoxicity assays were carried out to further investigate immunity and virus replication. Quantitative reverse-transcriptase polymerase chain reaction (q-RTPCR) was used to examine gene expression during reactivation. MHC expression on infected cells was analyzed by flow cytometry. Finally, T cells were depleted from latently-infected B cell-deficient mice to examine the in vivo difference in reactivation between wild-type and ΔM33stop. Results: We found that ΔM33stop triggers memory inflation specific for peptides derived from the immediate-early protein IE1 but not the early protein m164, in contrast to wild-type MCMV. During ex vivo reactivation, gene expression in DM33stop-infected lung tissues was delayed compared to wild-type virus. Normal gene expression was partially rescued by substitution of the HCMV US28 open reading frame in place of the M33 gene. In vivo depletion of T cells in immunoglobulin heavy chain-knockout mice resulted in reactivation of wild-type MCMV, but not ΔM33stop, confirming the role of M33 during reactivation from latency. Further, we found that M33 induces isotype-specific downregulation of MHC class I on the cell surface suggesting previously unappreciated roles in immune evasion. Discussion: Our results indicate that M33 is more polyfunctional than previously appreciated. In addition to its role in reactivation, which had been previously described, we found that M33 alters viral gene expression, host T cell memory inflation, and MHC class I expression. US28 was able to partially complement most functions of M33, suggesting that its role in HCMV infection may be similarly pleotropic.

Functional diversity: update of the posttranslational modification of Epstein-Barr virus coding proteins.

Epstein-Barr virus (EBV), a human oncogenic herpesvirus with a typical life cycle consisting of latent phase and lytic phase, is associated with many human diseases. EBV can express a variety of proteins that enable the virus to affect host cell processes and evade host immunity. Additionally, these proteins provide a basis for the maintenance of viral infection, contribute to the formation of tumors, and influence the occurrence and development of related diseases. Posttranslational modifications (PTMs) are chemical modifications of proteins after translation and are very important to guarantee the proper biological functions of these proteins. Studies in the past have intensely investigated PTMs of EBV-encoded proteins. EBV regulates the progression of the latent phase and lytic phase by affecting the PTMs of its encoded proteins, which are critical for the development of EBV-associated human diseases. In this review, we summarize the PTMs of EBV-encoded proteins that have been discovered and studied thus far with focus on their effects on the viral life cycle.

Knockout of signal peptide peptidase in the eye reduces HSV-1 replication and eye disease in ocularly infected mice.

We previously reported that knocking out signal peptide peptidase (SPP), a glycoprotein K (gK) binding partner, in mouse peripheral sensory neurons reduced latency-reactivation in infected mice without affecting primary virus replication or eye disease. Since virus replication in the eye plays an essential role in eye disease, we generated a conditional knockout mouse lacking SPP expression in the eye by crossing Pax6 (paired box 6)-Cre mice that have intact Pax6 expression with SPPflox/flox mice. Significantly less SPP protein expression was detected in the eyes of Pax6-SPP-/- mice than in WT control mice. HSV-1 replication in the eyes of Pax6-SPP-/- mice was significantly lower than in WT control mice. Levels of gB, gK, and ICP0 transcripts in corneas, but not trigeminal ganglia (TG), of Pax6-SPP-/- infected mice were also significantly lower than in WT mice. Corneal scarring and angiogenesis were significantly lower in Pax6-SPP-/- mice than in WT control mice, while corneal sensitivity was significantly higher in Pax6-SPP-/- mice compared with WT control mice. During acute viral infection, absence of SPP in the eye did not affect CD4 expression but did affect CD8α and IFNγ expression in the eye. However, in the absence of SPP, latency-reactivation was similar in Pax6-SPP-/- and WT control groups. Overall, our results showed that deleting SPP expression in the eyes reduced primary virus replication in the eyes, reduced CD8α and IFNγ mRNA expression, reduced eye disease and reduced angiogenesis but did not alter corneal sensitivity or latency reactivation to HSV-1 infection. Thus, blocking gK binding to SPP in the eye may have therapeutic potential by reducing both virus replication in the eye and eye disease associated with virus replication.

CCL2: a Chemokine Potentially Promoting Early Seeding of the Latent HIV Reservoir.

HIV infects long-lived CD4 memory T cells, establishing a latent viral reservoir that necessitates lifelong antiretroviral therapy (ART). How this reservoir is formed so quickly after infection remains unclear. We now show the innate inflammatory response to HIV infection results in CCL2 chemokine release, leading to recruitment of cells expressing the CCR2 receptor, including a subset of central memory CD4 T cells. Supporting a role for the CCL2/CCR2 axis in rapid reservoir formation, we find (i) treatment of humanized mice with anti-CCL2 antibodies during early HIV infection decreases reservoir seeding and preserves CCR2/5+ cells and (ii) CCR2/5+ cells from the blood of HIV-infected individuals on long-term ART contain significantly more integrated provirus than CCR2/5-negative memory or naive cells. Together, these studies support a model where the host's innate inflammatory response to HIV infection, including CCL2 production, leads to the recruitment of CCR2/5+ central memory CD4 T cells to zones of virus-associated inflammation, likely contributing to rapid formation of the latent HIV reservoir. IMPORTANCE There are currently over 35 million people living with HIV worldwide, and we still have no vaccine or scalable cure. One of the difficulties with HIV is its ability to rapidly establish a viral reservoir in lymphoid tissues that allows it to elude antivirals and the immune system. Thus, it is important to understand how HIV accomplishes this so we can develop preventive strategies. Our current results show that an early inflammatory response to HIV infection includes production of the chemokine CCL2, which recruits a unique subset of CCR2/5+ CD4+ T cells that become infected and form a significant reservoir for latent infection. Furthermore, we show that blockade of CCL2 in humanized mice significantly reduces persistent HIV infection. This information is relevant to the development of therapeutics to prevent and/or treat chronic HIV infections.