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

Potential pharmacological approaches for the treatment of HIV-1 associated neurocognitive disorders

HIV associated neurocognitive disorders (HAND) are the spectrum of cognitive impairments present in patients infected with human immunodeficiency virus type 1 (HIV-1). The number of patients affected with HAND ranges from 30 to 50% of HIV infected individuals and although the development of combinational antiretroviral therapy (cART) has improved longevity, HAND continues to pose a significant clinical problem as the current standard of care does not alleviate or prevent HAND symptoms. At present, the pathological mechanisms contributing to HAND remain unclear, but evidence suggests that it stems from neuronal injury due to chronic release of neurotoxins, chemokines, viral proteins, and proinflammatory cytokines secreted by HIV-1 activated microglia, macrophages and astrocytes in the central nervous system (CNS). Furthermore, the blood-brain barrier (BBB) not only serves as a route for HIV-1 entry into the brain but also prevents cART therapy from reaching HIV-1 brain reservoirs, and therefore could play an important role in HAND. The goal of this review is to discuss the current data on the epidemiology, pathology and research models of HAND as well as address the potential pharmacological treatment approaches that are being investigated.

Maternal death due to COVID-19

BACKGROUND

Despite 2.5 million infections and 169,000 deaths worldwide (as of April 20, 2020), no maternal deaths and only a few pregnant women afflicted with severe respiratory morbidity have been reported to be related to COVID-19 disease. Given the disproportionate burden of severe and fatal respiratory disease previously documented among pregnant women following other coronavirus-related outbreaks (SARS-CoV in 2003 and MERS-CoV in 2012) and influenza pandemics over the last century, the absence of reported maternal morbidity and mortality with COVID-19 disease is unexpected.

OBJECTIVE

To describe maternal and perinatal outcomes and death in a case series of pregnant women with COVID-19 disease.

STUDY DESIGN

We describe here a multiinstitution adjudicated case series from Iran that includes 9 pregnant women diagnosed with severe COVID-19 disease in their second or third trimester. All 9 pregnant women received a diagnosis of SARS-CoV-2 infection by reverse transcription polymerase chain reaction nucleic acid testing. Outcomes of these women were compared with their familial/household members with contact to the affected patient on or after their symptom onset. All data were reported at death or after a minimum of 14 days from date of admission with COVID-19 disease.

RESULTS

Among 9 pregnant women with severe COVID-19 disease, at the time of reporting, 7 of 9 died, 1 of 9 remains critically ill and ventilator dependent, and 1 of 9 recovered after prolonged hospitalization. We obtained self-verified familial/household cohort data in all 9 cases, and in each and every instance, maternal outcomes were more severe compared with outcomes of other high- and low-risk familial/household members (n=33 members for comparison).

CONCLUSION

We report herein maternal deaths owing to COVID-19 disease. Until rigorously collected surveillance data emerge, it is prudent to be aware of the potential for maternal death among pregnant women diagnosed as having COVID-19 disease in their second or third trimester.

Chloroquine and hydroxychloroquine in the management of COVID-19: Much kerfuffle but little evidence

Chloroquine and hydroxychloroquine are drugs that have shown in vitro activity on the replication of certain coronaviruses. In the context of the SARS-Cov-2 epidemic, the virus responsible for the novel coronavirus disease (COVID-19), these two drugs have been proposed as possible treatments. The results of the first clinical studies evaluating the effect of hydroxychloroquine do not support any efficacy of this drug in patients with COVID-19, due to major methodological weaknesses. Yet, these preliminary studies have aroused considerable media interest, raising fears of massive and uncontrolled use. In the absence of evidence of clinical benefits, the main risk is of exposing patients unnecessarily to the well-known adverse effects of hydroxychloroquine, with a possibly increased risk in the specific setting of COVID-19. In addition, widespread use outside of any recommendation risks compromising the completion of good quality clinical trials. The chloroquine hype, fueled by low-quality studies and media announcements, has yielded to the implementation of more than 150 studies worldwide. This represents a waste of resources and a loss of opportunity for other drugs to be properly evaluated. In the context of emergency, rigorous trials are more than ever needed in order to have, as soon as possible, reliable data on drugs that are possibly effective against the disease. Meanwhile, serious adverse drug reactions have been reported in patients with COVID-19 receiving hydroxychloroquine, justifying to limit its prescription, and to perform suitable cardiac and therapeutic drug monitoring.

Review on the Clinical Pharmacology of Hydroxychloroquine Sulfate for the Treatment of COVID-19

BACKGROUND

As the number of severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) infected people is greatly increasing worldwide, the international medical situation becomes very serious. Potential therapeutic drugs, vaccine and stem cell replacement methods are emerging, so it is urgent to find specific therapeutic drugs and the best treatment regimens. After the publications on hydroxychloroquine (HCQ) with anti- SARS-COV-2 activity in vitro, a small, non-randomized, open-label clinical trial showed that HCQ treatment was significantly associated with reduced viral load in patients with coronavirus disease-19 (COVID-19). Meanwhile, a large prophylaxis study of HCQ sulfate for COVID-19 has been initiated in the United States. HCQ offered a promising efficacy in the treatment of COVID-19, but the optimal administration is still being explored.

METHODS

We used the keyword "hydroxychloroquine" to conduct a literature search in PubMed to collect relevant literature on the mechanism of action of HCQ, its clinical efficacy and safety, pharmacokinetic characteristics, precautions for clinical use and drug interactions to extract and organize information.

RESULTS

This paper reviews the mechanism, clinical efficacy and safety, pharmacokinetic characteristics, exposureresponse relationship and precautions and drug interactions of HCQ, and summarizes dosage recommendations for HCQ sulfate.

CONCLUSION

It has been proved that HCQ, which has an established safety profile, is effective against SARS-CoV-2 with sufficient pre-clinical rationale and evidence. Data from high-quality clinical trials are urgently needed worldwide.

COVID-19 infection: the China and Italy perspectives

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the COVID-19 pandemic. Since its first report in December 2019, despite great efforts made in almost every country worldwide, this disease continues to spread globally, especially in most parts of Europe, Iran, and the United States. Here, we update the recent understanding in clinical characteristics, diagnosis strategies, as well as clinical management of COVID-19 in China as compared to Italy, with the purpose to integrate the China experience with the global efforts to outline references for prevention, basic research, treatment as well as final control of the disease. Being the first two countries we feel appropriate to evaluate the evolution of the disease as well as the early result of the treatment, in order to offer a different baseline to other countries. It is also interesting to compare two countries, with a very significant difference in population, where the morbidity and mortality has been so different, and unrelated to the size of the country.

Severe Acute Respiratory Syndrome Coronavirus 2: Genomic Observations and Emerging Therapies

Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2), the etiologic agent of the disease COVID-19, first emerged in late December 2019 in China, and has subsequently become a pandemic with unprecedented clinical impact. The virus appears to more severely affect older individuals and those with co-morbid medical conditions, specifically those with chronic lung disease, obesity, heart failure and diabetes. Fortunately, children appear to be less severely affected, though mortality and severe disease have been reported. In addition, children's role in spreading the disease (potentially through asymptomatic shedding of the virus) remains an important area requiring further investigation. The emergence of SARS-CoV-2 has highlighted the importance of metagenomic next generation sequencing as a tool for pandemic investigation. Though no proven therapeutic options currently exist, ongoing genomic and clinical trial data may help inform the identification and development of both repurposed and novel therapeutic agents for use in this disease.

Clinical evidence for repurposing chloroquine and hydroxychloroquine as antiviral agents: a systematic review

BACKGROUND

Repurposing hydroxychloroquine (HCQ) and chloroquine (CQ) as antiviral agents is a re-emerging topic with the advent of new viral epidemics.

AIMS

To summarize evidence from human clinical studies for using HCQ or CQ as antiviral agents for any viral infection.

SOURCES

PubMed, EMBASE, Scopus, Web of Science for published studies without time or language restrictions; Cochrane Clinical Trial Registry and Chinese Clinical Trials Registry for trials registered after 2015; MedRxiv for preprints within the last 12 months.

CONTENT

Study eligibility criteria were interventional and prospective observational studies (with or without a control group). Participants were adults and children with a confirmed viral infection. Interventions included the use of CQ or HCQ as antiviral agent in one or more groups of the study. Two authors independently screened abstracts, and all authors agreed on eligible studies. A meta-analysis was planned if studies were available which were similar in terms of participants, intervention, comparator and outcomes. Nineteen studies (including two preprints) were eligible (HIV 8, HCV 2, dengue 2, chikungunya 1, COVID-19 6). Nine and ten studies assessed CQ and HCQ respectively. Benefits of either drug for viral load suppression in HIV are inconsistent. CQ is ineffective in curing dengue (high-certainty evidence) and may have little or no benefit in curing chikungunya (low-certainty evidence). The evidence for COVID-19 infection is rapidly evolving but at this stage we are unsure whether either CQ or HCQ has any benefit in clearing viraemia (very-low-certainty evidence).

IMPLICATIONS

Using HCQ or CQ for HIV/HCV infections is now clinically irrelevant as other effective antivirals are available for viral load suppression (HIV) and cure (HCV). There is no benefit of CQ in dengue, and the same conclusion is likely for chikungunya. More evidence is needed to confirm whether either HCQ or CQ is beneficial in COVID-19 infection.

Assessment of Hydroxychloroquine and Chloroquine Safety Profiles: A Systematic Review and Meta-Analysis

BACKGROUND

Recently, chloroquine (CQ) and its derivative hydroxychloroquine (HCQ) have emerged as potential antiviral and immunomodulatory options for the treatment of 2019 coronavirus disease (COVID-19). To examine the safety profiles of these medications, we systematically evaluated the adverse events (AEs) of these medications from published randomized controlled trials (RCTs).

METHODS

We systematically searched PubMed, MEDLINE, Cochrane, the Cochrane Central Register of Controlled Trials (CENTRAL), EMBASE, and the ClinicalTrials.gov for all the RCTs comparing CQ or HCQ with placebo or other active agents, published before March 31, 2020. The random-effects or fixed-effects models were used to pool the risk estimates relative ratio (RR) with 95% confidence interval (CI) for the outcomes.

RESULTS

The literature search yielded 23 and 17 studies for CQ and HCQ, respectively, that satisfied our inclusion criteria. Of these studies, we performed meta-analysis on the ones that were placebo-controlled, which included 6 studies for CQ and 14 studies for HCQ. We did not limit our analysis to published reports involving viral treatment alone; data also included the usage of either CQ or HCQ for the treatment of other diseases. The trials for the CQ consisted of a total of 2,137 participants (n=1,077 CQ, n=1,060 placebo), while the trials for HCQ involved 1,096 participants (n=558 HCQ and n=538 placebo). The overall mild or total AEs were statistically higher comparing CQ or HCQ to placebo. The AEs were further categorized into four groups and analyses revealed that neurologic, gastrointestinal, dermatologic, and ophthalmic AEs were higher in participants taking CQ compared to placebo. Although this was not evident in HCQ treated groups, further analyses suggested that there were more AEs attributed to other organ system that were not included in the categorized meta-analyses. Additionally, meta-regression analyses revealed that total AEs was affected by dosage for the CQ group.

CONCLUSIONS

Taken together, we found that participants taking either CQ or HCQ have more AEs than participants taking placebo. Precautionary measures should be taken when using these drugs to treat COVID-19.

Cotrimoxazole reduces systemic inflammation in HIV infection by altering the gut microbiome and immune activation

Long-term cotrimoxazole prophylaxis reduces mortality and morbidity in HIV infection, but the mechanisms underlying these clinical benefits are unclear. Here, we investigate the impact of cotrimoxazole on systemic inflammation, an independent driver of HIV mortality. In HIV-positive Ugandan and Zimbabwean children receiving antiretroviral therapy, we show that plasma inflammatory markers were lower after randomization to continue (n = 144) versus stop (n = 149) cotrimoxazole. This was not explained by clinical illness, HIV progression, or nutritional status. Because subclinical enteropathogen carriage and enteropathy can drive systemic inflammation, we explored cotrimoxazole effects on the gut microbiome and intestinal inflammatory biomarkers. Although global microbiome composition was unchanged, viridans group Streptococci and streptococcal mevalonate pathway enzymes were lower among children continuing (n = 36) versus stopping (n = 36) cotrimoxazole. These changes were associated with lower fecal myeloperoxidase. To isolate direct effects of cotrimoxazole on immune activation from antibiotic effects, we established in vitro models of systemic and intestinal inflammation. In vitro cotrimoxazole had modest but consistent inhibitory effects on proinflammatory cytokine production by blood leukocytes from HIV-positive (n = 16) and HIV-negative (n = 8) UK adults and reduced IL-8 production by gut epithelial cell lines. Collectively we demonstrate that cotrimoxazole reduces systemic and intestinal inflammation both indirectly via antibiotic effects on the microbiome and directly by blunting immune and epithelial cell activation. Synergy between these pathways may explain the clinical benefits of cotrimoxazole despite high antimicrobial resistance, providing further rationale for extending coverage among people living with HIV in sub-Saharan Africa.

Therapeutic use of chloroquine and hydroxychloroquine in COVID-19 and other viral infections: A narrative review

The rapidly spreading Coronavirus Disease (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus (SARS-CoV-2), represents an unprecedented serious challenge to the global public health community. The extremely rapid international spread of the disease with significant morbidity and mortality made finding possible therapeutic interventions a global priority. While approved specific antiviral drugs against SARS-CoV-2 are still lacking, a large number of existing drugs are being explored as a possible treatment for COVID-19 infected patients. Recent publications have re-examined the use of Chloroquine (CQ) and/or Hydroxychloroquine (HCQ) as a potential therapeutic option for these patients. In an attempt to explore the evidence that supports their use in COVID-19 patients, we comprehensively reviewed the previous studies which used CQ or HCQ as an antiviral treatment. Both CQ and HCQ demonstrated promising in vitro results, however, such data have not yet been translated into meaningful in vivo studies. While few clinical trials have suggested some beneficial effects of CQ and HCQ in COVID-19 patients, most of the reported data are still preliminary. Given the current uncertainty, it is worth being mindful of the potential risks and strictly rationalise the use of these drugs in COVID-19 patients until further high quality randomized clinical trials are available to clarify their role in the treatment or prevention of COVID-19.

Nanocarriers For Vaginal Drug Delivery

BACKGROUND

Vaginal drug delivery approach represents one of the imperative strategies for local and systemic delivery of drugs. The peculiar dense vascular networks, mucus permeability, and range of physiological characteristics of the vaginal cavity have been exploited for therapeutic benefit. Furthermore, the vaginal drug delivery has been curtailed due to the influence of different physiological factors like acidic pH, constant cervical secretion, microflora, cyclic changes during periods along with turnover of mucus of varying thickness.

OBJECTIVE

This review highlights advancement of nanomedicine and its prospective progress towards the clinic.

METHODS

Relevant literature reports and patents related to topics are retrieved and used.

RESULT

The extensive literature search and patent revealed that nanocarriers are efficacious over conventional treatment approaches.

CONCLUSION

Recently, nanotechnology based drug delivery approach has promised better therapeutic outcomes by providing enhanced permeation and sustained drug release activity. Different nanoplatforms based on drugs, peptides, proteins, antigens, hormones, nucleic material, and microbicides are gaining momentum for vaginal therapeutics.

The Use of Antimalarial Drugs against Viral Infection

In recent decades, drugs used to treat malaria infection have been shown to be beneficial for many other diseases, including viral infections. In particular, they have received special attention due to the lack of effective antiviral drugs against new emerging viruses (i.e., HIV, dengue virus, chikungunya virus, Ebola virus, etc.) or against classic infections due to drug-resistant viral strains (i.e., human cytomegalovirus). Here, we reviewed the in vitro/in vivo and clinical studies conducted to evaluate the antiviral activities of four classes of antimalarial drugs: Artemisinin derivatives, aryl-aminoalcohols, aminoquinolines, and antimicrobial drugs.

Potential specific therapies in COVID-19

COVID-19 has grown into a global pandemic that has strained healthcare throughout the world. There is a sense of urgency in finding a cure for this deadly virus. In this study, we reviewed the empiric options used in common practice for COVID-19, based on the literature available online, with an emphasis on human experiences with these treatments on severe acute respiratory syndrome-associated coronavirus (SARS-COV-1) and other viruses. Convalescent blood products are the most promising potential treatment for use in COVID-19. The use of chloroquine or hydroxychloroquine (HCQ), remdesivir, and tocilizumab are some of the other promising potential therapies; however, they are yet to be tested in randomized clinical trials (RCTs). The use of lopinavir-ritonavir did not prove beneficial in a large RCT. The use of corticosteroids should be avoided in COVID-19 pneumonia unless used for other indications, based on the suggestion of harm in patients with SARS-COV-1 and Middle Eastern Respiratory Syndrome (MERS) infection. The reviews of this paper are available via the supplemental material section.

Two types of poor immunological responder showing distinct responses to long-term HAART

OBJECTIVES

Most previous studies on poor immunological responders (PIRs) have been performed on one cohort at one time-point following highly active antiretroviral therapy (HAART). The aim of this study was to investigate whether there are different subtypes of PIR and whether a certain population might achieve better immune reconstitution following longer HAART.

METHODS

This study was designed as an ambispective cohort study, including a 4-5-year retrospective study and a 2-year prospective follow-up investigation. Thymic output, activated T cell and regulatory T cell (Treg) subset frequencies, expression levels of interferon-stimulated genes, and plasma concentrations of neopterin were determined at 4-5 years and 6-7 years following HAART initiation.

RESULTS

PIRs were subdivided into two populations after 4-5 years of HAART, according to the kinetics of T cell recovery. Type II PIRs exhibited a significantly lower percentage of naïve CD4⁺ T cells and CD31⁺ naïve CD4⁺ T cells compared with type I PIRs. After an additional 2 years of HAART treatment, type I PIRs showed a better outcome than type II PIRs. Furthermore, it was found that 2 years of additional HAART could persistently improve thymic output.

CONCLUSIONS

The two PIR subgroups are different in terms of immune characteristics and the response to prolonged HAART.

Systemic lupus erythematosus in HIV: An insight into clinical implications and management

Although HIV infection can mimic the manifestations of various autoimmune disorders, the coexistence of HIV and systemic lupus erythematosus (SLE) has been rarely reported. The exact impact of HIV on SLE and vice versa is unclear. We report an HIV-seropositive female on highly active antiretroviral therapy presenting with features of SLE. Herein, an attempt has been made to discuss the various complex clinical and therapeutic implications along with the influence on disease course and prognosis.

Multiple Homozygous Variants in the STING-Encoding TMEM173 Gene in HIV Long-Term Nonprogressors

Among HIV-infected individuals, long-term nonprogressor (LTNP) patients experience slow CD4 T cell decline and almost undetectable viral load for several years after primary acquisition of HIV. Type I IFN has been suggested to play a pathogenic role in HIV pathogenesis, and therefore diminished IFN responses may underlie the LTNP phenotype. In this study, we examined the presence and possible immunological role of multiple homozygous single-nucleotide polymorphisms in the stimulator of IFN genes (STING) encoding gene TMEM173 involved in IFN induction and T cell proliferation in HIV LTNP patients. We identified LTNPs through the Danish HIV Cohort and performed genetic analysis by Sanger sequencing, covering the R71H-G230A-R293Q (HAQ) single-nucleotide polymorphisms in TMEM173 This was followed by investigation of STING mRNA and protein accumulation as well as innate immune responses and proliferation following STING stimulation and infection with replication-competent HIV in human blood-derived cells. We identified G230A-R293Q/G230A-R293Q and HAQ/HAQ homozygous TMEM173 variants in 2 out of 11 LTNP patients. None of the 11 noncontrollers on antiretroviral treatment were homozygous for these variants. We found decreased innate immune responses to DNA and HIV as well as reduced STING-dependent inhibition of CD4 T cell proliferation, particularly in the HAQ/HAQ HIV LTNP patients, compared with the age- and gender-matched noncontrollers on antiretroviral treatment. These findings suggest that homozygous HAQ STING variants contribute to reduced inhibition of CD4 T cell proliferation and a reduced immune response toward DNA and HIV, which might result in reduced levels of constitutive IFN production. Consequently, the HAQ/HAQ TMEM173 genotype may contribute to the slower disease progression characteristic of LTNPs.

Interferon-associated therapies toward HIV control: The back and forth

Human immunodeficiency virus (HIV) induces a persistent and incurable infection. However, the combined antiretroviral treatment (cART) has markedly changed the evolution of the infection and transformed a deadly disease into a manageable chronic infection. Withdrawal of cART generally leads though to resumption of the viral replication. The eradication of the virus from its cellular and anatomical reservoirs remains a goal-to-achieve for a cure. In this context, developing novel therapies contributing to this aim are an important field of research. Type I IFN has antiviral activity, which, before the presence of efficient anti-HIV drugs, has led to the testing of IFN-based therapeutic strategies during the early years of the pandemic. A historical overview of the results and its limitations that were put into light are reviewed here. In addition, several lessons could be drawn. For instance, the efficacy of the IFN-I depends on the timing of its administration and the context. Thus, the persistence of an endogenous IFN-signature, such as that generally observed in viremic patients, seems to be associated with a lower efficacy of IFN. Based on the lessons from previous trials, and in the context of cART and research for a cure, type I Interferon has regained interest and novel therapeutic approaches are currently tested in combination with cART, some with disappointing, other with encouraging results with regard to a reduction in the size of the HIV reservoir and/or delays in viral rebound after cessation of cART. Additional strategies are currently developed in addition to improve the antiviral function of the IFN-I, by using for instance other IFN subtypes than IFN-Iα2. In parallel, the development of innovative strategies aimed at counteracting the excessive activation of the IFN-pathways have been continued and their results are reviewed here as well. Altogether, the use of IFN-I in anti-HIV therapies has gone through distinct phases and many lessons could be drawn. Novel combinations are currently be tested that might provide interesting results.

The Significance of Type-I Interferons in the Pathogenesis and Therapy of Human Immunodeficiency Virus 1 Infection

Type-I interferons (IFN-I) are a widely expressed family that could promote antivirus immunity in the process of pathogens invasion. In a human immunodeficiency virus 1 (HIV-1)-infected individual, the production of IFN-I can be detected as early as the acute phase and will persist throughout the course of infection. However, sustained stimulation of immune system by IFN-I also contributes greatly to host-mediated immunopathology and diseases progression. Although the protective effects of IFN-I in the acute phase of HIV-1 infection have been observed, more studies recently focus on their detrimental role in the chronic stage. Inhibition of IFN-I signaling may reverse HIV-1-induced immune hyperactivation and furthermore reduce HIV-1 reservoirs, which suggest this strategy may provide a potential way to enhance the therapeutic effect of antiretroviral therapy. Therefore, we review the role of IFN-I in HIV-1 progression, their effects on different immunocytes, and therapeutic prospects targeting the IFN-I system.

HIV as a Cause of Immune Activation and Immunosenescence

Systemic immune activation has emerged as an essential component of the immunopathogenesis of HIV. It not only leads to faster disease progression, but also to accelerated decline of overall immune competence. HIV-associated immune activation is characterized by an increase in proinflammatory mediators, dysfunctional T regulatory cells, and a pattern of T-cell-senescent phenotypes similar to those seen in the elderly. These changes predispose HIV-infected persons to comorbid conditions that have been linked to immunosenescence and inflamm-ageing, such as atherosclerosis and cardiovascular disease, neurodegeneration, and cancer. In the antiretroviral treatment era, development of such non-AIDS-defining, age-related comorbidities is a major cause of morbidity and mortality. Treatment strategies aimed at curtailing persistent immune activation and inflammation may help prevent the development of these conditions. At present, the most effective strategy appears to be early antiretroviral treatment initiation. No other treatment interventions have been found effective in large-scale clinical trials, and no adjunctive treatment is currently recommended in international HIV treatment guidelines. This article reviews the role of systemic immune activation in the immunopathogenesis of HIV infection, its causes and the clinical implications linked to immunosenescence in adults, and the therapeutic interventions that have been investigated.

Add-on Pyridostigmine Enhances CD4+ T-Cell Recovery in HIV-1-Infected Immunological Non-Responders: A Proof-of-Concept Study

Background

In human immunodeficiency virus (HIV)-infection, persistent T-cell activation leads to rapid turnover and increased cell death, leading to immune exhaustion and increased susceptibility to opportunistic infections. Stimulation of the vagus nerve increases acetylcholine (ACh) release and modulates inflammation in chronic inflammatory conditions, a neural mechanism known as the cholinergic anti-inflammatory pathway (CAP). Pyridostigmine (PDG), an ACh-esterase inhibitor, increases the half-life of endogenous ACh, therefore mimicking the CAP. We have previously observed that PDG reduces ex vivo activation and proliferation of T-cells obtained from people living with HIV.

Methods

We conducted a 16-week proof-of-concept open trial using PDG as add-on therapy in seven HIV-infected patients with discordant immune response receiving combined antiretroviral therapy, to determine whether PDG would promote an increase in total CD4⁺ T-cells. The trial was approved by the Institutional Research and Ethics Board and registered in ClinicalTrials.gov (NCT00518154).

Results

Seven patients were enrolled after signing informed consent forms. We observed that addition of PDG induced a significant increase in total CD4⁺ T-cells (baseline = 153.1 ± 43.1 vs. week-12 = 211.9 ± 61.1 cells/µL; p = 0.02). Post hoc analysis showed that in response to PDG, four patients (57%) significantly increased CD4⁺ T-cell counts (responders = 257.8 ± 26.6 vs. non-responders = 150.6 ± 18.0 cells/µL; p = 0.002), and the effect persisted for at least 1 year after discontinuation of PDG.

Conclusion

Our data indicate that in patients with HIV, add-on PDG results in a significant and persistent increase in circulating CD4⁺ T-cells.

Impact of Connective Tissue Disease on Oncologic Breast Surgery and Reconstruction

BACKGROUND

The impact of connective tissue disease (CTD) on outcomes following breast surgery and reconstruction is unknown. The purpose of this study was to evaluate the effect of both CTDs and systemic immunomodulatory therapy on outcomes following breast surgery and reconstruction.

METHODS

A retrospective review was performed of all patients from 2005 to 2010 with an active CTD who underwent breast surgery with or without reconstruction. Surgical events were assigned to 1 of 4 groups: ablative surgery alone, autologous reconstruction, implant reconstruction, and revision surgery. Logistic regression was utilized to examine the relationship between complications and type of surgery, CTD diagnosis, and immunomodulatory therapy. Four non-CTD control groups were then compiled for outcome comparison. The a priori P-value was set at P < 0.05, and all tests were 2 sided.

RESULTS

Thirty-three patients with CTD underwent112 procedures. Diagnoses included psoriasis/psoriatic arthritis (n = 12), rheumatoid arthritis (n = 10), lupus (n = 4), scleroderma (n = 3), Sjogren syndrome (n = 2), mixed CTD (n = 1), and seronegative polyarthritis (n = 1). Nineteen of 33 (58%) patients who received systemic treatment for CTD in the perioperative period were less likely to experience a minor complication compared with those without treatment (odds ratio= 0.69; P = 0.019). There were no differences in postoperative complications in patients with CTD compared with control groups.

CONCLUSIONS

Ablative breast surgery and reconstruction among patients with CTDs can be performed safely with low perioperative complication rates. Patients receiving systemic therapy, and continuing their regimens perioperatively, experience complication rates similar to those not requiring therapy.

Chloroquine inhibits Ca2+ permeable ion channels-mediated Ca2+ signaling in primary B lymphocytes

BACKGROUND

Chloroquine, a bitter tastant, inhibits Ca²⁺ signaling, resulting in suppression of B cell activation; however, the inhibitory mechanism remains unclear.

RESULTS

In this study, thapsigargin (TG), but not caffeine, induced sustained intracellular Ca²⁺ increases in mouse splenic primary B lymphocytes, which were markedly inhibited by chloroquine. Under Ca²⁺-free conditions, TG elicited transient Ca²⁺ increases, which additionally elevated upon the restoration of 2 mM Ca²⁺. The former were from release of intracellular Ca²⁺ store and the latter from Ca²⁺ influx. TG-induced release was inhibited by 2-APB (an inhibitor of inositol-3-phosphate receptors, IP₃Rs) and chloroquine, and TG-caused influx was inhibited by pyrazole (Pyr3, an inhibitor of transient receptor potential C3 (TRPC3) and stromal interaction molecule (STIM)/Orai channels) and chloroquine. Moreover, chloroquine also blocked Ca²⁺ increases induced by the engagement of B cell receptor (BCR) with anti-IgM.

CONCLUSIONS

These results indicate that chloroquine inhibits Ca²⁺ elevations in splenic B cells through inhibiting Ca²⁺ permeable IP₃R and TRPC3 and/or STIM/Orai channels. These findings suggest that chloroquine would be a potent immunosuppressant.

Antiviral activity of cationic amphiphilic drugs

Introduction: Emerging and reemerging viral infections represent a major concern for human and veterinary public health and there is an urgent need for the development of broad-spectrum antivirals.

Areas covered: A recent strategy in antiviral research is based on the identification of molecules targeting host functions required for infection of multiple viruses. A number of FDA-approved drugs used to treat several human diseases are cationic amphiphilic drugs (CADs) that have the ability to accumulate inside cells affecting several structures/functions hijacked by viruses during infection. In this review we summarized the CADs’ chemical properties and effects on the cells and reported the main FDA-approved CADs that have been identified so far as potential antivirals in drug repurposing studies.

Expert commentary: Although there have been concerns regarding the efficacy and the possible side effects of the off-label use of CADs as antivirals, they seem to represent a promising starting point for the development of broad-spectrum antiviral strategies. Further knowledge about their mechanism of action is required to improve their antiviral activity and to reduce the risk of side effects.

Immunosenescence and hurdles in the clinical management of older HIV-patients

People living with HIV (PLWH) who are treated with effective highly active antiretroviral therapy (HAART) have a similar life expectancy to the general population. Moreover, an increasing proportion of new HIV diagnoses are made in people older than 50 y. The number of older HIV-infected patients is thus constantly growing and it is expected that by 2030 around 70% of PLWH will be more than 50 y old. On the other hand, HIV infection itself is responsible for accelerated immunosenescence, a progressive decline of immune system function in both the adaptive and the innate arm, which impairs the ability of an individual to respond to infections and to give rise to long-term immunity; furthermore, older patients tend to have a worse immunological response to HAART. In this review we focus on the pathogenesis of HIV-induced immunosenescence and on the clinical management of older HIV-infected patients.

Targeting endosomal acidification by chloroquine analogs as a promising strategy for the treatment of emerging viral diseases

Emerging viruses such as HIV, dengue, influenza A, SARS coronavirus, Ebola, and other viruses pose a significant threat to human health. Majority of these viruses are responsible for the outbreaks of pathogenic lethal infections. To date, there are no effective therapeutic strategies available for the prophylaxis and treatment of these infections. Chloroquine analogs have been used for decades as the primary and most successful drugs against malaria. Concomitant with the emergence of chloroquine‐resistant Plasmodium strains and a subsequent decrease in the use as antimalarial drugs, other applications of the analogs have been investigated. Since the analogs have interesting biochemical properties, these drugs are found to be effective against a wide variety of viral infections. As antiviral action, the analogs have been shown to inhibit acidification of endosome during the events of replication and infection. Moreover, immunomodulatory effects of analogs have been beneficial to patients with severe inflammatory complications of several viral diseases. Interestingly, one of the successful targeting strategies is the inhibition of HIV replication by the analogs in vitro which are being tested in several clinical trials. This review focuses on the potentialities of chloroquine analogs for the treatment of endosomal low pH dependent emerging viral diseases.

Immune activation and immune aging in HIV infection

PURPOSE OF REVIEW

The development of serious non-AIDS-related pathologies typically associated with aging, and the premature immune aging that characterizes HIV-1-infected patients, even with suppressive antiretroviral therapy, have raised increasing concerns in recent years. Deciphering the causes of these phenomena is key for our understanding of HIV pathogenesis and for the clinical care of patients living with the virus.

RECENT FINDINGS

An important basis for the immune parallels between HIV infection and aging lies in the exhaustion of the lymphopoietic capacity of infected individuals, which eventually affects all compartments of the immune system. The alleged cause for these immune alterations, and the onset of age-related comorbidities, is the systemic chronic immune activation that is established in patients. However, there is a multiplicity of contributors to this immune activation.

SUMMARY

Our understanding of the precise link between immune activation and aging in HIV infection is complicated by the influence of coinfections and life style factors. Developing rational interventions to reduce the hyper-inflammatory status of HIV-1-infected patients requires a clearer delineation of the factors contributing to the increased levels of systemic immune activation.

The Effect of Chloroquine on Immune Activation and Interferon Signatures Associated with HIV-1

Immune activation associated with HIV-1 infection contributes to morbidity and mortality. We studied whether chloroquine, through Toll-like receptor (TLR) antagonist properties, could reduce immune activation thought to be driven by TLR ligands, such as gut-derived bacterial elements and HIV-1 RNAs. AIDS Clinical Trials Group A5258 was a randomized, double-blind, placebo-controlled study in 33 HIV-1-infected participants off antiretroviral therapy (ART) and 37 participants on ART. Study participants in each cohort were randomized 1:1 to receive chloroquine 250 mg orally for the first 12 weeks then cross over to placebo for 12 weeks or placebo first and then chloroquine. Combining the periods of chloroquine use in both arms of the on-ART cohort yielded a modest reduction in the proportions of CD8 T cells co-expressing CD38 and DR (median decrease = 3.0%, p = .003). The effect on immune activation in the off-ART cohort was likely confounded by increased plasma HIV-1 RNA during chloroquine administration (median 0.29 log10 increase, p < .001). Transcriptional analyses in the off-ART cohort showed decreased expression of interferon-stimulated genes in 5 of 10 chloroquine-treated participants and modest decreases in CD38 and CCR5 RNAs in all chloroquine-treated participants. Chloroquine modestly reduced immune activation in ART-treated HIV-infected participants. Clinical Trials Registry Number: NCT00819390.

Inflammation, immune activation, and cardiovascular disease in HIV

Cardiovascular disease is one of the leading causes of morbidity and mortality in people living with HIV. Several epidemiological studies have shown an increased risk of myocardial infarction and stroke compared to uninfected controls. Although traditional risk factors contribute to this increased risk of cardiovascular disease, HIV-specific mechanisms likely also play a role. Systemic inflammation has been linked to cardiovascular disease in several populations suffering from chronic inflammation, including people living with HIV. Although antiretroviral therapy reduces immune activation, levels of inflammatory markers remain elevated compared to uninfected controls. The causes of this sustained immune response are likely multifactorial and incompletely understood. In this review, we summarize the evidence describing the relationship between inflammation and cardiovascular disease and discuss potential anti-inflammatory treatment options for cardiometabolic disease in people living with HIV.

Rheumatoid arthritis in patients with HIV: management challenges

Over the past few decades, HIV has been transformed from a once-uniformly fatal disease to now a manageable but complex multisystem illness. Before highly active antiretroviral therapy (HAART), reports suggested that HIV-infected patients with rheumatoid arthritis (RA) would experience remission of their disease. It has now become clear that RA can develop in HIV-infected patients at any time, independent of HAART. Choosing the right medication to treat symptoms related to RA while avoiding excess weakening of the immune system remains a clinical challenge. Agents such as hydroxychloroquine and sulfasalazine might best balance safety with efficacy, making them reasonable first choices for therapy in HIV-infected patients with RA. More immune suppressing agents such as methotrexate may balance safety with efficacy, but data are limited. Corticosteroids such as prednisone may also be reasonable but could increase the risk of osteonecrosis. Among biologic response modifiers, tumor necrosis factor α inhibitors may balance safety with efficacy, but perhaps when HIV replication is controlled with HAART. Monitoring RA disease activity remains challenging as only one retrospective study has been published in this area. Those with HIV infection and RA can experience comorbidities such as accelerated heart disease and osteoporosis, a consequence of the chronic inflammatory state that each illness generates. Although HIV-infected patients are at risk for developing the immune reconstitution inflammatory syndrome when starting HAART, it appears that immune reconstitution inflammatory syndrome has a minimal effect on triggering the onset or the worsening of RA.

Chloroquine could be used for the treatment of filoviral infections and other viral infections that emerge or emerged from viruses requiring an acidic pH for infectivity

Viruses from the Filoviridae family, as many other virus families, require an acidic pH for successful infection and are therefore susceptible to the actions of 4‐aminoquinolines, such as chloroquine.

Although the mechanisms of action of chloroquine clearly indicate that it might inhibit filoviral infections, several clinical trials that attempted to use chloroquine in the treatment of other acute viral infections – including dengue and influenza A and B – caused by low pH‐dependent viruses, have reported that chloroquine had no clinical efficacy, and these results demoted chloroquine from the potential treatments for other virus families requiring low pH for infectivity.

The present review is aimed at investigating whether chloroquine could combat the present Ebola virus epidemic, and also at exploring the main reasons for the reported lack of efficacy. Literature was sourced from PubMed, Scopus, Google Scholar, reference list of articles and textbooks – Fields Virology (Volumes 1and 2), the cytokine handbook, Pharmacology in Medicine: Principles and Practice, and hydroxychloroquine and chloroquine retinopathy.

The present analysis concludes that (1) chloroquine might find a place in the treatment of Ebola, either as a monotherapy or in combination therapies; (2) the ineffectiveness of chloroquine, or its analogue, hydroxychloroquine, at treating infections from low pH‐dependent viruses is a result of the failure to attain and sustain a steady state concentration sufficient to increase and keep the pH of the acidic organelles to approximately neutral levels; (3) to successfully treat filoviral infections – or other viral infections that emerge or emerged from low pH‐dependent viruses – a steady state chloroquine plasma concentration of at least 1 µg/mL(~3.125 μM/L) or a whole blood concentration of 16 μM/L must be achieved and be sustained until the patients' viraemia becomes undetectable. These concentrations, however, do not rule out the efficacy of other, higher, steady state concentrations – although such concentrations might be accompanied by severe adverse effects or toxicities. The feasibility of the conclusion in the preceding texts has recently been supported by a subsequent study that shows that amodiaquine, a derivative of CQ, is able to protect humans infected with Ebola from death.

Type I interferon: understanding its role in HIV pathogenesis and therapy

Despite over 30 years of research, the contribution of type I interferons (IFN-Is) to both the control of HIV replication and initiation of immunologic damage remains debated. In acute infection, IFN-Is, likely from plasmacytoid dendritic cells (pDCs), activate NK cells and upregulate restriction factors targeting virtually the entire HIV life cycle. In chronic infection, IFN-Is may also contribute to CD4 T cell loss and immune exhaustion. pDCs subsequently infiltrate lymphoid and mucosal tissues, and their circulating populations wane in chronic infection; IFN-I may be produced by other cells. Data from nonhuman primates indicate prompt IFN-I signaling is critical in acute infection. Whereas some studies showed IFN-I administration without combination antiretroviral therapy (cART) is beneficial, others suggest that stimulating or blocking IFN-I signaling in chronic ART-suppressed HIV infection has had positive results. Here, we describe the history of HIV and IFN-I, IFN-I's sources, IFN-I's effects on HIV control and host defense, and recent interventional studies in SIV and HIV infection.

HIV-1 Env Glycoprotein Phenotype along with Immune Activation Determines CD4 T Cell Loss in HIV Patients

The mechanism behind the selective depletion of CD4(+) cells in HIV infections remains undetermined. Although HIV selectively infects CD4(+) cells, the relatively few infected cells in vivo cannot account for the extent of CD4(+) T cell depletion, suggesting indirect or bystander mechanisms. The role of virus replication, Env glycoprotein phenotype, and immune activation (IA) in this bystander phenomenon remains controversial. Using samples derived from HIV-infected patients, we demonstrate that, although IA in both CD4(+) and CD8(+) subsets correlates with CD4 decline, apoptosis in CD4(+) and not CD8(+) cells is associated with disease progression. Because HIV-1 Env glycoprotein has been implicated in bystander apoptosis, we cloned full-length Envs from plasma of viremic patients and tested their apoptosis-inducing potential (AIP). Interestingly, AIP of HIV-1 Env glycoproteins were found to correlate inversely with CD4:CD8 ratios, suggesting a role of Env phenotype in disease progression. In vitro mitogenic stimulation of PBMCs resulted in upregulation of IA markers but failed to alter the CD4:CD8 ratio. However, coculture of normal PBMCs with Env-expressing cells resulted in selective CD4 loss that was significantly enhanced by IA. Our study demonstrates that AIP of HIV-1 Env and IA collectively determine CD4 loss in HIV infection.

The enigma of the clandestine association between chloroquine and HIV-1 infection

OBJECTIVES

The antimalarial drug chloroquine (CQ) dampens the immune system and is used in the treatment of autoimmune disorders. CQ also shows antiviral activity against nonenveloped and enveloped viruses, including HIV-1. Persistent immune activation in chronic HIV-1infection leads to CD4 T-cell depletion. CQ is envisioned to attenuate immune activation and virus activity in HIV-1-infected patients. The role of CQ in immune activation and virus activity is discussed here.

METHODS

To elucidate the effect of CQ on immune activation, a retrospective review of published clinical trials, in vivo experimental studies in animals, and the most relevant in vitro observations in HIV-1-infected cells, together with observations from our own laboratory studies, was carried out and the findings discussed.

RESULTS

In a few clinical studies and animal experiments, CQ was ineffective in decreasing immune activation and HIV-1 infection. In vitro, CQ markedly increased HIV-1 infection in astrocytes and other non-CD4 cells.

CONCLUSIONS

The use of CQ in HIV-1-infected patients is questionable. The evidence for a dampening of immune activation by CQ is inconclusive.

Chloroquine and beyond: exploring anti-rheumatic drugs to reduce immune hyperactivation in HIV/AIDS

The restoration of the immune system prompted by antiretroviral therapy (ART) has allowed drastically reducing the mortality and morbidity of HIV infection. However, one main source of clinical concern is the persistence of immune hyperactivation in individuals under ART. Chronically enhanced levels of T-cell activation are associated with several deleterious effects which lead to faster disease progression and slower CD4⁺ T-cell recovery during ART. In this article, we discuss the rationale, and review the results, of the use of antimalarial quinolines, such as chloroquine and its derivative hydroxychloroquine, to counteract immune activation in HIV infection. Despite the promising results of several pilot trials, the most recent clinical data indicate that antimalarial quinolines are unlikely to exert a marked beneficial effect on immune activation. Alternative approaches will likely be required to reproducibly decrease immune activation in the setting of HIV infection. If the quinoline-based strategies should nevertheless be pursued in future studies, particular care must be devoted to the dosage selection, in order to maximize the chances to obtain effective in vivo drug concentrations.

Herpes simplex virus type 2 serostatus is not associated with inflammatory or metabolic markers in antiretroviral therapy-treated HIV

Systemic inflammation and immune activation may persist in HIV-infected persons on suppressive combination antiretroviral therapy (cART) and contribute to adverse health outcomes. We compared markers of immune activation, inflammation, and abnormal glucose and lipid metabolism in HIV-infected adults according to herpes simplex virus type 2 (HSV-2) serostatus in a 6-month observational cohort study in Toronto, Canada. HIV-infected adults on suppressive (viral load <50 copies/ml) cART were categorized as HSV-2 seropositive or seronegative using the HerpeSelect ELISA, and underwent study visits at baseline, 3 months, and 6 months. The primary outcome was the median percentage of activated (CD38(+)HLADR(+)) CD8 T cells. Secondary outcome measures included additional immune (activated CD4, regulatory T cells) and inflammatory (hsCRP, D-dimer, IL-1b, IL-6, MCP-1, TNF, sICAM-1, sVCAM-1, Ang1/Ang2 ratio) markers. Metabolic outcomes included the proportion with impaired fasting glucose/impaired glucose tolerance/diabetes, insulin sensitivity (calculated using the Matsuda index), insulin resistance (homeostasis model assessment of insulin resistance), and fasting lipids. The impact of HSV-2 on each outcome was estimated using generalized estimating equation regression models. Of 84 participants, 38 (45%) were HSV-2 seropositive. HSV signs and symptoms were uncommon. Aside from D-dimer, which was more often detectable in HSV-2 seropositives (adjusted odds ratio=3.58, 95% CI=1.27, 10.07), HSV-2 serostatus was not associated with differences in any other immune, inflammatory cytokine, acute phase reactant, endothelial activation, or metabolic markers examined in univariable or multivariable models. During the study, CD8 and CD4 T cell activation declined by 0.16% and 0.08% per month, respectively, while regulatory T cells increased by 0.05% per month. HSV-2 serostatus was not consistently associated with immune activation, inflammatory, or lipid and glucose metabolic markers in this cohort of HIV-infected adults on suppressive cART.

Tripterygium wilfordii Hook F extract in cART-treated HIV patients with poor immune response: a pilot study to assess its immunomodulatory effects and safety

BACKGROUND

Despite combination antiretroviral therapy (cART), 20% of HIV-infected patients are unable to achieve adequate immunologic recovery, in which immune activation plays a crucial role. We hypothesize that extract of Tripterygium wilfordii Hook F (TwHF), a Chinese medication used to treat autoimmune diseases, has immunomodulatory effects that may help CD4 cell recovery.

METHODS

Eighteen cART-treated HIV-infected patients virally suppressed for over 12 months with suboptimal CD4 cell recovery were enrolled. TwHF extract was administered at a dosage of 10 mg three times daily for 12 months. T-cell subsets and activation markers were evaluated at baseline and during follow-up. The trial was registered at Clinicaltrials.gov (NCT02002286).

RESULTS

TwHF extract was associated with a mean increase in CD4 cell count of 88 cells/μl (95% confidential interval [CI], 72-105 cells/μl) after one year of treatment. A significant increase in the mean rate of CD4 cell recovery (26 before vs 75 cells/μl/year after TwHF use, P < 0.001) was observed. Analysis of 13 patients with activation profiles suggested that TwHF extract was associated with a decrease in T-cell immune activation which was temporally correlated with CD4 cell recovery. No discontinuation of TwHF extract was reported.

CONCLUSION

Use of TwHF extract in HIV-infected patients was associated with a reduction in T-cell activation and improved CD4 recovery with an excellent safety profile.

HIV Type 1 Disease Progression to AIDS and Death in a Rural Ugandan Cohort Is Primarily Dependent on Viral Load Despite Variable Subtype and T-Cell Immune Activation Levels

BACKGROUND

Untreated human immunodeficiency virus type 1 (HIV) infection is associated with persistent immune activation, which is an independent driver of disease progression in European and United States cohorts. In Uganda, HIV-1 subtypes A and D and recombinant AD viruses predominate and exhibit differential rates of disease progression.

METHODS

HIV-1 seroconverters (n = 156) from rural Uganda were evaluated to assess the effects of T-cell activation, viral load, and viral subtype on disease progression during clinical follow-up.

RESULTS

The frequency of activated T cells was increased in HIV-1-infected Ugandans, compared with community matched uninfected individuals, but did not differ significantly between viral subtypes. Higher HIV-1 load, subtype D, older age, and high T-cell activation levels were associated with faster disease progression to AIDS or death. In a multivariate Cox regression analysis, HIV-1 load was the strongest predictor of progression, with subtype also contributing. T-cell activation did not emerge an independent predictor of disease progression from this particular cohort.

CONCLUSIONS

These findings suggest that the independent contribution of T-cell activation on morbidity and mortality observed in European and North American cohorts may not be directly translated to the HIV epidemic in East Africa. In this setting, HIV-1 load appears to be the primary determinant of disease progression.

Inflammatory co-morbidities in HIV+ individuals: learning lessons from healthy ageing

Increased life expectancy due to improved efficacy of cART has uncovered an increased risk of age-related morbidities in HIV+ individuals and catalyzed significant research into mechanisms driving these diseases. HIV infection increases the risk of non-communicable diseases common in the aged, including cardiovascular disease, neurocognitive decline, non-AIDS malignancies, osteoporosis, and frailty. These observations suggest that HIV accelerates immunological ageing, and there are many immunological similarities with the aged, including shortened telomeres, accumulation of senescent T cells and altered monocyte phenotype/function. However, the most critical similarity between HIV+ individuals and the elderly, which most likely underpins the heightened risk of non-communicable diseases, is chronic inflammation and associated immune activation. Here, we review the similarities between HIV+ individuals and the aged regarding the pathogenesis of inflammatory diseases, the current evidence for mechanisms driving these processes and discuss current and potential therapeutic strategies for addressing inflammatory co-morbidity in HIV+ infection.

Hydroxychloroquine-inhibited dengue virus is associated with host defense machinery

Hydroxychloroquine (HCQ) is an antimalarial drug also used in treating autoimmune diseases. Its antiviral activity was demonstrated in restricting HIV infection in vitro; however, the clinical implications remain controversial. Infection with dengue virus (DENV) is a global public health problem, and we lack an antiviral drug for DENV. Here, we evaluated the anti-DENV potential of treatment with HCQ. Immunofluorescence assays demonstrated that HCQ could inhibit DENV serotype 1-4 infection in vitro. RT-qPCR analysis of HCQ-treated cells showed induced expression of interferon (IFN)-related antiviral proteins and certain inflammatory cytokines. Mechanistic study suggested that HCQ activated the innate immune signaling pathways of IFN-β, AP-1, and NFκB. Knocking down mitochondrial antiviral signaling protein (MAVS), inhibiting TANK binding kinase 1 (TBK1)/inhibitor-κB kinase ɛ (IKKɛ), and blocking type I IFN receptor reduced the efficiency of HCQ against DENV-2 infection. Furthermore, HCQ significantly induced cellular production of reactive oxygen species (ROS), which was involved in the host defense system. Suppression of ROS production attenuated the innate immune activation and anti-DENV-2 effect of HCQ. In summary, HCQ triggers the host defense machinery by inducing ROS- and MAVS-mediated innate immune activation against DENV infection and may be a candidate drug for DENV infection.

Plasmacytoid dendritic cells suppress HIV-1 replication but contribute to HIV-1 induced immunopathogenesis in humanized mice

The role of plasmacytoid dendritic cells (pDC) in human immunodeficiency virus type 1 (HIV-1) infection and pathogenesis remains unclear. HIV-1 infection in the humanized mouse model leads to persistent HIV-1 infection and immunopathogenesis, including type I interferons (IFN-I) induction, immune-activation and depletion of human leukocytes, including CD4 T cells. We developed a monoclonal antibody that specifically depletes human pDC in all lymphoid organs in humanized mice. When pDC were depleted prior to HIV-1 infection, the induction of IFN-I and interferon-stimulated genes (ISGs) were abolished during acute HIV-1 infection with either a highly pathogenic CCR5/CXCR4-dual tropic HIV-1 or a standard CCR5-tropic HIV-1 isolate. Consistent with the anti-viral role of IFN-I, HIV-1 replication was significantly up-regulated in pDC-depleted mice. Interestingly, the cell death induced by the highly pathogenic HIV-1 isolate was severely reduced in pDC-depleted mice. During chronic HIV-1 infection, depletion of pDC also severely reduced the induction of IFN-I and ISGs, associated with elevated HIV-1 replication. Surprisingly, HIV-1 induced depletion of human immune cells including T cells in lymphoid organs, but not the blood, was reduced in spite of the increased viral replication. The increased cell number in lymphoid organs was associated with a reduced level of HIV-induced cell death in human leukocytes including CD4 T cells. We conclude that pDC play opposing roles in suppressing HIV-1 replication and in promoting HIV-1 induced immunopathogenesis. These findings suggest that pDC-depletion and IFN-I blockade will provide novel strategies for treating those HIV-1 immune non-responsive patients with persistent immune activation despite effective anti-retrovirus treatment.

Assessment of chloroquine as a modulator of immune activation to improve CD4 recovery in immune nonresponding HIV-infected patients receiving antiretroviral therapy

OBJECTIVES

Chloroquine (CQ), an anti-inflammatory drug, inhibits Toll-like receptor (TLR) signalling in plasmacytoid dendritic cells (pDCs) and may be beneficial for HIV-infected patients in whom immune activation persists despite effective antiretroviral therapy (ART). The effect of CQ on CD4 T-cell recovery and immune activation in immune nonresponding patients receiving successful ART was therefore studied.

METHODS

Nineteen adults on ART with CD4 counts ≤ 350 cells/μL and undetectable viral load (VL) orally received CQ at 250 mg/day for 24 weeks. Side effects, CD4 and CD8 T-cell counts, VL, T-cell activation, pDC proportion and plasma inflammatory markers were assessed at baseline, at 24 weeks, and at 12 weeks after CQ discontinuation (clinicaltrial.org registration #NCT02004314).

RESULTS

CQ was well tolerated and all patients maintained an undetectable VL. The absolute CD4 and CD8 T-cell counts and their percentages, the pDC proportion, T-cell activation, D-dimer and C-reactive protein (CRP) plasma levels and the kynurenine/tryptophan ratio did not change with CQ treatment. Among nine cytokines/chemokines measured, only levels of interferon (IFN)-α2 were significantly increased by CQ treatment.

CONCLUSIONS

CQ was well tolerated in patients with low CD4 T-cell counts despite long-term effective ART; however, 24 weeks of CQ treatment did not improved CD4 T-cell recovery, lymphoid and myeloid immune activation or inflammatory markers.

Hydroxychloroquine: a multifaceted treatment in lupus

The efficacy of antimalarials, especially hydroxychloroquine (HCQ), in preventing systemic lupus erythematosus (SLE) flares is well demonstrated. However, many studies show that the percentage of SLE patients treated with HCQ remains low. By blocking the toll-like receptor 7 and 9 in plasmacytoid dendritic cells, HCQ inhibits interferon-alpha production which plays a crucial role in SLE pathogenesis. In addition to reducing damage accrual in SLE patients, HCQ appears to protect against the occurrence of diabetes, thrombotic events, and dyslipidemia. As a consequence, some studies have suggested that HCQ, which is inexpensive, has a protective effect on survival in SLE patients. Thanks to the pharmacokinetic properties of HCQ (long half-life) and to the availability of its blood assay, very low or undetectable blood HCQ concentrations are a valuable marker of non-adherence to treatment, thus adding a new benefit to HCQ prescriptions. The main side effect of HCQ is retinal toxicity. This complication is very rare, but may be potentially severe, thus requiring regular screening. Retinal toxicity remains the only absolute contra-indication of HCQ in adult SLE patients. Other contra-indications are few and rare. During pregnancy and breast-feeding, HCQ continuation is not only allowed but recommended. In conclusion, the risk/benefit ratio of HCQ is excellent. Many now believe that all SLE patients should be offered this treatment.

Immune responses during spontaneous control of HIV and AIDS: what is the hope for a cure?

HIV research has made rapid progress and led to remarkable achievements in recent decades, the most important of which are combination antiretroviral therapies (cART). However, in the absence of a vaccine, the pandemic continues, and additional strategies are needed. The 'towards an HIV cure' initiative aims to eradicate HIV or at least bring about a lasting remission of infection during which the host can control viral replication in the absence of cART. Cases of spontaneous and treatment-induced control of infection offer substantial hope. Here, we describe the scientific knowledge that is lacking, and the priorities that have been established for research into a cure. We discuss in detail the immunological lessons that can be learned by studying natural human and animal models of protection and spontaneous control of viraemia or of disease progression. In particular, we describe the insights we have gained into the immune mechanisms of virus control, the impact of early virus-host interactions and why chronic inflammation, a hallmark of HIV infection, is an obstacle to a cure. Finally, we enumerate current interventions aimed towards improving the host immune response.