Effects of hydroxychloroquine on immune activation and disease progression among HIV-infected patients not receiving antiretroviral therapy: a randomized controlled trial

HIV-1 latency: an update of molecular mechanisms and therapeutic strategies

The major obstacle towards HIV-1 eradication is the life-long persistence of the virus in reservoirs of latently infected cells. In these cells the proviral DNA is integrated in the host’s genome but it does not actively replicate, becoming invisible to the host immune system and unaffected by existing antiviral drugs. Rebound of viremia and recovery of systemic infection that follows interruption of therapy, necessitates life-long treatments with problems of compliance, toxicity, and untenable costs, especially in developing countries where the infection hits worst. Extensive research efforts have led to the proposal and preliminary testing of several anti-latency compounds, however, overall, eradication strategies have had, so far, limited clinical success while posing several risks for patients. This review will briefly summarize the more recent advances in the elucidation of mechanisms that regulates the establishment/maintenance of latency and therapeutic strategies currently under evaluation in order to eradicate HIV persistence.

Modulation of HIV-1-induced activation of plasmacytoid dendritic cells by 6-desfluoroquinolones

Chronic activation of plasmacytoid dendritic cells (pDCs) is an important contributor to the immunopathogenesis of HIV infection. The quinolone derivative chloroquine (CQ) prevents endosomal acidification, required for toll-like receptor sensing of HIV by pDCs, and is currently under clinical trial as an immunotherapeutic approach. We tested three different 6-desfluoroquinolones (6-DFQs), structurally related to CQ and endowed with antiretroviral activity, for their ability to inhibit HIV-induced pDC activation and interferon (IFN)-α production in peripheral blood mononuclear cells (PBMCs) in vitro. PBMCs from six healthy donors were cultured overnight with aldrithiol-2 (AT-2)-inactivated HIV-1MN in the presence or absence of 6-DFQs or CQ. IFN-α production was measured by ELISA; pDC and monocyte activation was analyzed by flow cytometry. Incubation with HIV labeled with the fluorescent dye DyLight-488 (DL488) was used to test virus uptake by flow cytometry. We found that the 6-DFQs effectively inhibited HIV-induced IFN-α similar to CQ, but only 6-DFQs also inhibited the upregulation of the pDC activation marker CD83. Interestingly, HIV-induced expression of the costimulatory molecule CD80 and, to a lesser extent CD86, was further enhanced on pDCs by 6-DFQs, but not CQ. Conversely, 6-DFQs and CQ had similar inhibitory effects on HIV-induced monocyte activation, consistent with the primary mechanism being associated with IFN-α signaling. Finally, 6-DFQs interfered with HIV interaction with pDCs and monocytes, but not myeloid DCs. Our data indicate that 6-DFQs may interfere with pDC-mediated and IFN-α-dependent immunopathogenesis while supporting pDC differentiation into mature antigen-presenting cells by favoring expression of costimulatory molecules.

Transient increase of interferon-stimulated genes and no clinical benefit by chloroquine treatment during acute simian immunodeficiency virus infection of macaques

Simian immunodeficiency virus (SIV) infection leads to AIDS in experimentally infected Rhesus macaques similarly to HIV-infected humans. In contrast, SIV infection of natural hosts is characterized by a down-regulation of innate acute responses to the virus within a few weeks of infection and results in limited pathology. Chloroquine (CQ) has been used in the treatment or prevention of malaria and has recently been shown to cause a decrease of immune activation and CD4 cell loss in HIV-infected individuals treated with antiretroviral therapy. Here, we treated Rhesus macaques with CQ during the acute phase of SIVmac251 infection with the intent to decrease viral-induced immune activation and possibly limit disease progression. Contrary to what was expected, CQ treatment resulted in a temporary increased expression of interferon (IFN)-stimulating genes and it worsened the recovery of CD4(+) T cells in the blood. Our findings confirm recent results observed in asymptomatic HIV-infected patients and suggest that CQ does not provide an obvious benefit in the absence of antiretroviral therapy.

HIV cure research: advances and prospects

Thirty years after the identification of HIV, a cure for HIV infection is still to be achieved. Advances of combined antiretroviral therapy (cART) in recent years have transformed HIV infection into a chronic disease when treatment is available. However, in spite of the favorable outcomes provided by the newer therapies, cART is not curative and patients are at risk of developing HIV-associated disorders. Moreover, universal access to antiretroviral treatment is restricted by financial obstacles. This review discusses the most recent strategies that have been developed in the search for an HIV cure and to improve life quality of people living with HIV.

Interferon-alpha, immune activation and immune dysfunction in treated HIV infection

Type I interferons (IFNs) exert anti-viral effects through the induction of numerous IFN-stimulated genes and an immunomodulatory effect on innate and adaptive immune responses. This is beneficial in controlling virus infections but prolonged IFN-α activity in persistent virus infections, such as HIV infection, may contribute to immune activation and have a detrimental effect on the function of monocytes and T and B lymphocytes. Activation of monocytes, associated with increased IFN-α activity, contributes to atherosclerotic vascular disease, brain disease and other ‘age-related diseases' in HIV patients treated with long-term antiretroviral therapy (ART). In HIV patients receiving ART, the anti-viral effects of IFN-α therapy have the potential to contribute to eradication of HIV infection while IFN-α inhibitor therapy is under investigation for the treatment of immune activation. The management of HIV patients receiving ART will be improved by understanding more about the opposing effects of IFN-α on HIV infection and disease and by developing methods to assess IFN-α activity in clinical practice.

Systemic effects of inflammation on health during chronic HIV infection

Combination antiretroviral therapy for HIV infection improves immune function and eliminates the risk of AIDS-related complications but does not restore full health. HIV-infected adults have excess risk of cardiovascular, liver, kidney, bone, and neurologic diseases. Many markers of inflammation are elevated in HIV disease and strongly predictive of the risk of morbidity and mortality. A conceptual model has emerged to explain this syndrome of diseases where HIV-mediated destruction of gut mucosa leads to local and systemic inflammation. Translocated microbial products then pass through the liver, contributing to hepatic damage, impaired microbial clearance, and impaired protein synthesis. Chronic activation of monocytes and altered liver protein synthesis subsequently contribute to a hypercoagulable state. The combined effect of systemic inflammation and excess clotting on tissue function leads to end-organ disease. Multiple therapeutic interventions designed to reverse these pathways are now being tested in the clinic. It is likely that knowledge gained on how inflammation affects health in HIV disease could have implications for our understanding of other chronic inflammatory diseases and the biology of aging.

Serious Non-AIDS events: Immunopathogenesis and interventional strategies

Despite the major advances in the management of HIV infection, HIV-infected patients still have greater morbidity and mortality than the general population. Serious non-AIDS events (SNAEs), including non-AIDS malignancies, cardiovascular events, renal and hepatic disease, bone disorders and neurocognitive impairment, have become the major causes of morbidity and mortality in the antiretroviral therapy (ART) era. SNAEs occur at the rate of 1 to 2 per 100 person-years of follow-up. The pathogenesis of SNAEs is multifactorial and includes the direct effect of HIV and associated immunodeficiency, underlying co-infections and co-morbidities, immune activation with associated inflammation and coagulopathy as well as ART toxicities. A number of novel strategies such as ART intensification, treatment of co-infection, the use of anti-inflammatory drugs and agents that reduce microbial translocation are currently being examined for their potential effects in reducing immune activation and SNAEs. However, currently, initiation of ART before advanced immunodeficiency, smoking cessation, optimisation of cardiovascular risk factors and treatment of HCV infection are most strongly linked with reduced risk of SNAEs or mortality. Clinicians should therefore focus their attention on addressing these issues prior to the availability of further data.

Decoding the complexity of type I interferon to treat persistent viral infections

Type I interferons (IFN-I) are a broad family of cytokines that are central to the innate immune response. These proteins have long been appreciated for the critical roles they play in restraining viral infections and shaping antiviral immune responses. However, in recent years there has been increased awareness of the immunosuppressive actions of these proteins as well. Although there are many current therapeutic applications to manipulate IFN-I pathways, we have limited understanding of the mechanisms by which these therapies are actually functioning. In this review, we highlight the diversity and temporal impact of IFN-I signaling, discuss the current therapeutic uses of IFN-I, and explore the strategy of blocking IFN-I to alleviate immune dysfunction in persistent virus infections.

Evidence for compliance with long-term medication: a systematic review of randomised controlled trials

BACKGROUND

Pharmacists play a pivotal role in optimising medication use which often includes actions to maximise compliance with long-term medication. The best evidence to support medication use is derived from randomised controlled trials (RCTs). It is often assumed that 100 % compliance is required to obtain the outcomes identified in the trial. This assumption needs to be examined.

OBJECTIVE

To systematically review the reporting of compliance in RCTs of long-term medications.

METHOD

RCTs published in the New England Journal of Medicine, Journal of the American Medical Association, Lancet and BMJ in 2012, were reviewed to identify trials of medications for long-term use in adults. These trials were examined to evaluate the reporting of compliance.

MAIN OUTCOME MEASURES

The proportion of trials reporting compliance data, the methods used, and the proportion of trials using more than one method to determine compliance.

RESULTS

Of the 289 RCTs published in 2012, 25 assessed long-term medications in adults. Compliance was reported in 12 (48 %) studies and only 2 (8 %) studies used more than one method to measure compliance. Pill count was the most commonly reported method for measuring compliance, with patient reports and blood levels also being used.

CONCLUSION

The reporting of compliance in RCTs is poor and the methodology inconsistent. The methods used overestimate compliance. If compliance in a clinical trial is low, the evidence for the effectiveness and most importantly safety of the medication(s) is questionable. Two or more methods, one of which is standardised, should be used to measure compliance in clinical trials. The requirement to report compliance should be included in publication guidelines.

PUMA: a puzzle piece in chloroquine's antimelanoma activity

Chloroquine (CQ) can induce cell death in a subset of cancer cell lines, and some melanoma cell lines are quite susceptible. Although it is well known that CQ impairs lysosomal function and can serve as an autophagy inhibitor, the molecular target of CQ and the subsequent cascade of events that lead to cell death are not fully understood. Recent evidence indicates that in melanoma cell lines, CQ induces apoptosis by preventing degradation of the pro-apoptotic BH3-only protein p53-upregulated modulator of apoptosis. This finding adds to the unfolding story of CQ's mechanism of action as a cancer therapeutic agent.

Cardiovascular disease and HIV infection

The emergence of chronic disease complications in controlled HIV disease has changed the landscape of HIV clinical care. HIV infection confers an increased cardiovascular disease risk, which is thought to be due to a complex interplay of mechanistic factors. While traditional cardiovascular risk factors likely play a role, recent evidence suggests that HIV-associated inflammation and immune activation are important mediators of cardiovascular risk. It is unclear whether established preventative interventions for the general population are applicable to HIV-infected patients, and the need to translate mechanistic knowledge into HIV-specific clinical interventions represents an important priority. Developing strategies to prevent cardiovascular disease in HIV-infected individuals calls for a multidisciplinary approach and represents an opportunity to exert a major public health impact in an at-risk population.

Distribution of hydroxychloroquine in lymphoid tissue in a rabbit model for HIV infection

Hydroxychloroquine has been proposed for HIV treatment; however, little is known about its disposition in the lymphatic system, where replication takes place. Therefore, its distribution in lymphoid tissues (Peyer's patches and popliteal, submandibular, femoral, splenic, and prescapular lymph nodes) was evaluated and compared with that in blood. Results showed a high affinity of hydroxychloroquine for all of these tissues, with higher affinity for the splenic and submandibular lymph nodes, suggesting its potential use as a coadjuvant in HIV therapy.

Residual immune dysregulation syndrome in treated HIV infection

Antiretroviral therapy has revolutionized the course of HIV infection, improving immune function and decreasing dramatically the mortality and morbidity due to the opportunistic complications of the disease. Nonetheless, even with sustained suppression of HIV replication, many HIV-infected persons experience a syndrome characterized by increased T cell activation and evidence of heightened inflammation and coagulation. This residual immune dysregulation syndrome or RIDS is more common in persons who fail to increase circulating CD4+ T cells to normal levels and in several epidemiologic studies it has been associated with increased morbidity and mortality. These morbid and fatal events are not the typical opportunistic infections and malignancies seen in the early AIDS era but rather comprise a spectrum of cardiovascular events, liver disease, metabolic disorders, kidney disease, bone disease, and a spectrum of malignant complications distinguishable from the opportunistic malignancies that characterized the earlier days of the AIDS epidemic. While immune activation, inflammation, and coagulopathy are characteristic of untreated HIV infection and improve with drug-induced control of HIV replication, the drivers of RIDS in treated HIV infection are incompletely understood. And while inflammation, immune activation, and coagulopathy are more common in treated persons who fail to restore circulating CD4+ T cells, it is not entirely clear how these two phenomena are linked.

Incidence and time trends of herpes zoster in rheumatoid arthritis: a population-based cohort study

OBJECTIVE

To determine the incidence, time trends, risk factors, and severity of herpes zoster in a population-based cohort of patients with newly diagnosed rheumatoid arthritis (RA) compared to a group of individuals without RA from the same population.

METHODS

All residents of Olmsted County, Minnesota fulfilling for the first time the 1987 American College of Rheumatology criteria for RA between January 1, 1980 and December 31, 2007 and a cohort of similar residents without RA were assembled and followed by retrospective chart review until death, migration, or December 31, 2008.

RESULTS

There was no difference in the presence of herpes zoster prior to the RA incidence/index date between the cohorts (P = 0.85). During followup, 84 patients with RA (rate 12.1 cases per 1,000 person-years) and 44 subjects without RA (rate 5.4 cases per 1,000 person-years) developed herpes zoster. Patients with RA were more likely to develop herpes zoster than those without RA (hazard ratio [HR] 2.4 [95% confidence interval (95% CI) 1.7-3.5]). Herpes zoster occurred more frequently in patients diagnosed with RA more recently (HR 1.06 per year [95% CI 1.02-1.10]). Erosive disease, previous joint surgery, and use of hydroxychloroquine and corticosteroids were significantly associated with the development of herpes zoster in RA. There was no apparent association of herpes zoster with the use of methotrexate or biologic agents. Complications of herpes zoster occurred at a similar rate in both cohorts.

CONCLUSION

The incidence of herpes zoster is increased in RA and has risen in recent years. There also has been an increasing incidence of herpes zoster in more recent years in the general population. RA disease severity is associated with the development of herpes zoster.

Understanding and controlling chronic immune activation in the HIV-infected patients suppressed on combination antiretroviral therapy

Combination antiretroviral therapy (cART) has resulted in tremendous gains in survival among HIV-infected patients, but as a group those who achieve undetectable viral loads on cART experience a greater degree of immune activation and inflammation than the general population. HIV-infected patients continue to experience premature immune senescence with earlier and more frequent non-AIDS events compared to HIV-uninfected individuals. Chronic immune activation during suppressive cART derives from a variety of sources mediated by cytokines, chemokines, coagulation, microbial translocation, immune regulators and T(effector) cell activation abnormalities, among others. Current investigational strategies to control immune activation target potential causes of persistently heightened immune activation during cART such as microbial translocation, co-infections, and comorbidities or mediators along a common final pathway. Although several interventions have shown promise in vitro or in preliminary clinical trials, no intervention has sufficient evidence for routine use, making control of immune activation during cART an unmet need.

HIV-associated chronic immune activation

Systemic chronic immune activation is considered today as the driving force of CD4(+) T-cell depletion and acquired immunodeficiency syndrome (AIDS). A residual chronic immune activation persists even in HIV-infected patients in which viral replication is successfully inhibited by anti-retroviral therapy, with the extent of this residual immune activation being associated with CD4(+) T-cell loss. Unfortunately, the causal link between chronic immune activation and CD4(+) T-cell loss has not been formally established. This article provides first a brief historical overview on how the perception of the causative role of immune activation has changed over the years and lists the different kinds of immune activation characteristic of human immunodeficiency virus (HIV) infection. The mechanisms proposed to explain the chronic immune activation are multiple and are enumerated here, as well as the mechanisms proposed on how chronic immune activation could lead to AIDS. In addition, we summarize the lessons learned from natural hosts that know how to 'show AIDS the door', and discuss how these studies informed the design of novel immune modulatory interventions that are currently being tested. Finally, we review the current approaches aimed at targeting chronic immune activation and evoke future perspectives.

Barriers to a cure for HIV: new ways to target and eradicate HIV-1 reservoirs

Antiretroviral therapy for HIV infection needs lifelong access and strict adherence to regimens that are both expensive and associated with toxic effects. A curative intervention will be needed to fully stop the epidemic. The failure to eradicate HIV infection during long-term antiretroviral therapy shows the intrinsic stability of the viral genome in latently infected CD4T cells and other cells, and possibly a sustained low-level viral replication. Heterogeneity in latently infected cell populations and homoeostatic proliferation of infected cells might affect the dynamics of virus production and persistence. Despite potent antiretroviral therapy, chronic immune activation, inflammation, and immune dysfunction persist, and are likely to have important effects on the size and distribution of the viral reservoir. The inability of the immune system to recognise cells harbouring latent virus and to eliminate cells actively producing virus is the biggest challenge to finding a cure. We look at new approaches to unravelling the complex virus-host interactions that lead to persistent infection and latency, and discuss the rationale for combination of novel treatment strategies with available antiretroviral treatment options to cure HIV.

Safety and immunological responses to human mesenchymal stem cell therapy in difficult-to-treat HIV-1-infected patients

OBJECTIVE

HAART largely decreases morbidity and mortality in chronic HIV-1-infected patients, but immune nonresponders (INRs) with full viral suppression still fail to reverse the immune deficiency. This study evaluated the safety and immunological responses of human umbilical cord mesenchymal stem cell (MSC) therapy in HIV-1-infected INRs.

DESIGN AND METHODS

A total of 13 HIV-1-infected INRs were enrolled in this pilot prospectively open-labeled controlled clinical trial. Seven patients were administered three umbilical cord-MSC transfusions at 1-month interval during 12-months of follow-up, whereas six control patients were treated with saline in parallel. Immunological parameters were monitored in these patients throughout the trial.

RESULTS

All patients tolerated the umbilical cord-MSC transfusions well throughout the trial. The umbilical cord-MSC transfusions preferentially increased circulating naive and central memory CD4 T-cell counts and restored HIV-1-specific IFN-γ and IL-2 production in the INRs. These enhancements in immune reconstitution were also associated with the reduction of systemic immune activation and inflammation in vivo.

CONCLUSIONS

umbilical cord-MSC transfusions are well tolerated and can efficiently improve host immune reconstitution in INRs, suggesting that such treatments may be used as a novel immunotherapeutic approach to reversing immune deficiency in HIV-1-infected INRs (ClinicalTrials.gov identifier: NCT01213186).

Metabolic stress in infected cells may represent a therapeutic target for human immunodeficiency virus infection

Worldwide, there are thousands of new cases of human immunodeficiency virus-1 (HIV-1) infection per day. The effectiveness of current combination antiretroviral therapy (ART) is relative; to prioritize finding vaccines and/or cure-oriented initiatives should be reinforced because there is little room, if any, for procrastination. Basic and clinical findings on HIV-1 reservoirs suggest that disruption of virus latency is feasible. Because the goal is curing HIV-1 infection, we should be aware that the challenge is to eradicate the viruses of every single infected cell and consequently acting upon virus latency is necessary but not sufficient. The large majority of the virus reservoir, CD4(+) T lymphocytes, is readily accessible but other minor reservoirs, where ART does not diffuse, require innovative strategies. The situation closely resembles that currently faced in the treatment of cancer. Exploiting the fact that histone deacetylase inhibitors, mainly vorinostat, may disrupt the latency of HIV-1, we propose to supplement this effect with a programmed interference in the metabolic stress of infected cells. Metformin and chloroquine are cheap and accessible modulators of pro-survival mechanisms to which viruses are constantly confronted to generate alternative energy sources and maximize virus production. Metformin restrains the use of the usurped cellular biosynthetic machinery by viral genes and chloroquine contributes to death of infected cells. We suggest that the combination of vorinostat, chloroquine and metformin should be combined with ART to pursue viral eradication in infected cells.

Can immunotherapy be useful as a "functional cure" for infection with Human Immunodeficiency Virus-1?

Immunotherapy aims to assist the natural immune system in achieving control over viral infection. Various immunotherapy formats have been evaluated in either therapy-naive or therapy-experienced HIV-infected patients over the last 20 years. These formats included non-antigen specific strategies such as cytokines that stimulate immunity or suppress the viral replication, as well as antibodies that block negative regulatory pathways. A number of HIV-specific therapeutic vaccinations have also been proposed, using in vivo injection of inactivated virus, plasmid DNA encoding HIV antigens, or recombinant viral vectors containing HIV genes. A specific format of therapeutic vaccines consists of ex vivo loading of autologous dendritic cells with one of the above mentioned antigenic formats or mRNA encoding HIV antigens.This review provides an extensive overview of the background and rationale of these different therapeutic attempts and discusses the results of trials in the SIV macaque model and in patients. To date success has been limited, which could be explained by insufficient quality or strength of the induced immune responses, incomplete coverage of HIV variability and/or inappropriate immune activation, with ensuing increased susceptibility of target cells.Future attempts at therapeutic vaccination should ideally be performed under the protection of highly active antiretroviral drugs in patients with a recovered immune system. Risks for immune escape should be limited by a better coverage of the HIV variability, using either conserved or mosaic sequences. Appropriate molecular adjuvants should be included to enhance the quality and strength of the responses, without inducing inappropriate immune activation. Finally, to achieve a long-lasting effect on viral control (i.e. a "functional cure") it is likely that these immune interventions should be combined with anti-latency drugs and/or gene therapy.