Immunomodulatory Effects of Hydroxychloroquine and Chloroquine in Viral Infections and Their Potential Application in Retinal Gene Therapy

Novel quinoline substituted autophagy inhibitors attenuate Zika virus replication in ocular cells

Zika virus (ZIKV) is a re-emerging RNA virus that is known to cause ocular and neurological abnormalities in infants. ZIKV exploits autophagic processes in infected cells to enhance its replication and spread. Thus, autophagy inhibitors have emerged as a potent therapeutic target to combat RNA viruses, with Hydroxychloroquine (HCQ) being one of the most promising candidates. In this study, we synthesized several novel small-molecule quinoline derivatives, assessed their antiviral activity, and determined the underlying molecular mechanisms. Among the nine synthesized analogs, two lead candidates, labeled GL-287 and GL-382, significantly attenuated ZIKV replication in human ocular cells, primarily by inhibiting autophagy. These two compounds surpassed the antiviral efficacy of HCQ and other existing autophagy inhibitors, such as ROC-325, DC661, and GNS561. Moreover, unlike HCQ, these novel analogs did not exhibit cytotoxicity in the ocular cells. Treatment with compounds GL-287 and GL-382 in ZIKV-infected cells increased the abundance of LC3 puncta, indicating the disruption of the autophagic process. Furthermore, compounds GL-287 and GL-382 effectively inhibited the ZIKV-induced innate inflammatory response in ocular cells. Collectively, our study demonstrates the safe and potent antiviral activity of novel autophagy inhibitors against ZIKV.

Effects of prolonged hydroxychloroquine use on the pancreatic tissue and expected ameliorative effect of lactoferrin in rats (biochemical, histological, and morphometric study)

Hydroxychloroquine (HCQ), an antimalarial drug widely used in treating rheumatoid disorders. Many side effects have been reported with HCQ administration indicating its hazardous effects on various organs. No previous studies reported the effect of long-term administration of oral HCQ on pancreatic tissue. Our study assessed pancreatic tissues functional and histopathological alterations following prolonged oral administration of HCQ. We also investigated the possible ameliorative effects of the lactoferrin (LF) coadministration with HCQ in adult male albino rats. Forty adult male Wister albino rats were divided into: negative control, LF positive control (2 g/kg), HCQ-treated (200 mg/kg), and HCQ+LF treated. Biochemical, histological, immunohistochemical, and morphometric analyses of the pancreatic tissues were conducted. Our findings revealed that prolonged oral administration of HCQ induced significant disruption of the pancreatic acinar architecture, enlarged congested islets of Langerhans, and elevated plasma insulin, amylase, and lipase levels. Interestingly, LF administration ameliorated the deleterious effects of prolonged HCQ administration on pancreatic tissue of adult male albino rats. In conclusion, prolonged oral administration of HCQ induced pancreatic tissue damage in rats, while LF attenuates HCQ-induced pancreatic injury. Our results emphasized the necessity of prescribing HCQ with caution, considering both dosage and treatment duration.

Amplified Type I Interferon Response in Sjögren's Disease via Ectopic Toll-Like Receptor 7 Expression in Salivary Gland Epithelial Cells Induced by Lysosome-Associated Membrane Protein 3

OBJECTIVE

Lysosome-associated membrane protein 3 (LAMP3) misexpression in salivary gland epithelial cells plays a causal role in the development of salivary gland dysfunction and autoimmunity associated with Sjögren's disease (SjD). This study aimed to clarify how epithelial LAMP3 misexpression is induced in SjD.

METHODS

To explore upstream signaling pathways associated with LAMP3 expression, we conducted multiple RNA sequencing analyses of minor salivary glands from patients with SjD, submandibular glands from a mouse model of SjD, and salivary gland epithelial cell lines. A hypothesis generated by the RNA sequencing analyses was further tested by in vitro and in vivo assays with gene manipulation.

RESULTS

Transcriptome analysis suggested LAMP3 expression was associated with enhanced type I interferon (IFN) and IFNγ signaling pathways in patients with SjD. In vitro studies showed that type I IFN but not IFNγ stimulation could induce LAMP3 expression in salivary gland epithelial cells. Moreover, we discovered that LAMP3 overexpression could induce ectopic Toll-like receptor 7 (TLR-7) expression and type I IFN production in salivary gland epithelial cells both in vitro and in vivo. TLR-7 knockout mice did not develop any SjD-related symptoms following LAMP3 induction.

CONCLUSION

Epithelial LAMP3 misexpression can be induced through enhanced type I IFN response in salivary glands. In addition, LAMP3 can promote type I IFN production via ectopic TLR-7 expression in salivary gland epithelial cells. This positive feedback loop can contribute to maintaining LAMP3 misexpression and amplifying type I IFN production in salivary glands, which plays an essential role in the pathophysiology of SjD.

Hydroxychloroquine-induced hyperpigmentation of the skin and bull's-eye maculopathy in rheumatic patients: a case report and literature review

Hydroxychloroquine (HCQ) is used as a traditional disease-modifying antirheumatic drugs (DMARDs), for the treatment of autoimmune diseases such as rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). However, it can cause serious adverse reactions, including hyperpigmentation of the skin and bull's-eye macular lesions. Here, we present a case of HCQ-induced hyperpigmentation of the skin and bull's-eye macular lesions in a patient who received HCQ for RA. A 65-year-old female patient developed blurred vision and hyperpigmentation of multiple areas of skin over the body for one month after 3 years of HCQ treatment for RA. Based on clinical presentation, ophthalmological examination and dermatopathological biopsy, a diagnosis of drug-induced cutaneous hyperpigmentation and bullous maculopathy of the right eye was made. After discontinuation of HCQ and treatment with iguratimod tablets, the hyperpigmentation of the patient 's skin was gradually reduced, and the symptoms of blurred vision were not significantly improved. We also reviewed the available literature on HCQ-induced cutaneous hyperpigmentation and bull's-eye macular lesions and described the clinical features of HCQ-induced cutaneous hyperpigmentation and bull's-eye macular lesions. In conclusion, clinicians should be aware of early cutaneous symptoms and HCQ-associated ophthalmotoxicity in patients with rheumatic diseases on HCQ sulphate and should actively monitor patients, have them undergo regular ophthalmological examinations and give appropriate treatment to prevent exacerbation of symptoms.

Hydroxychloroquine exacerbates imiquimod-induced psoriasis-like dermatitis through stimulating overexpression of IL-6 in keratinocytes

OBJECTIVE

Hydroxychloroquine (HCQ) is a US Food and Drug Administration (FDA)-approved treatment for systemic lupus erythematosus (SLE) through inhibition of antigen presentation and subsequent reduction in T cell activation. Psoriasis relapse after antimalarial therapy have been reported in up to 18% of patients with psoriasis. Here, we explored the role of HCQ on exacerbating dermatitis utilizing an imiquimod (IMQ)-induced psoriasis-like dermatitis mouse model.

METHODS

Thirty-six C57BL/6 female mice were divided into six groups: wild-type control, IMQ-Only, pre-treat HCQ (30 mg/kg and 60 mg/kg HCQ), and co-treat HCQ with IMQ (30 mg/kg and 60 mg/kg HCQ). Besides control, all were topically treated with IMQ for 5 days. Pharmacological effects and mechanisms of HCQ were assessed by clinical severity of dermatitis, histopathology, and flow cytometry. HaCaT cells were co-treated with both HCQ and recombinant IL-17A, followed by the detection of proinflammatory cytokine expression and gene profiles through enzyme-linked immunosorbent assay and next-generation sequencing.

RESULTS

In the pre-treated and co-treated HCQ groups, skin redness and scaling were significantly increased compared to the IMQ-Only group, and Th17 cell expression was also upregulated. Acanthosis and CD11b+IL23+ dendritic cell (DC) infiltration were observed in the HCQ treatment group. IL-6 overexpression was detected in both the HaCaT cells and skin from the experimental mice. Psoriasis-related genes were regulated after being co-treated with HCQ and recombinant IL-17A in HaCaT cells.

CONCLUSIONS

HCQ exacerbates psoriasis-like skin inflammation by increasing the expression of IL-6, stimulating DC infiltration, and promoting Th17 expression in the microenvironment of the skin.

KEY MESSAGES

This study provided possible mechanisms for inducing psoriasis during HCQ treatment through an animal model.

Infusion reactions to adeno-associated virus (AAV)-based gene therapy: Mechanisms, diagnostics, treatment and review of the literature

The use of adeno-associated virus (AAV) vectors in gene therapy has demonstrated great potential in treating genetic disorders. However, infusion-associated reactions (IARs) pose a significant challenge to the safety and efficacy of AAV-based gene therapy. This review provides a comprehensive summary of the current understanding of IARs to AAV therapy, including their underlying mechanisms, clinical presentation, and treatment options. Toll-like receptor activation and subsequent production of pro-inflammatory cytokines are associated with IARs, stimulating neutralizing antibodies (Nabs) and T-cell responses that interfere with gene therapy. Risk factors for IARs include high titers of pre-existing Nabs, previous exposure to AAV, and specific comorbidities. Clinical presentation ranges from mild flu-like symptoms to severe anaphylaxis and can occur during or after AAV administration. There are no established guidelines for pre- and postadministration tests for AAV therapies, and routine laboratory requests are not standardized. Treatment options include corticosteroids, plasmapheresis, and supportive medications such as antihistamines and acetaminophen, but there is no consensus on the route of administration, dosage, and duration. This review highlights the inadequacy of current treatment regimens for IARs and the need for further research to improve the safety and efficacy of AAV-based gene therapy.

NETosis: an emerging therapeutic target in renal diseases

Introduction

Neutrophil extracellular traps (NETs) are web-like structures composed of nuclear and granular components. The primary role of NETS is to prevent the dissemination of microbes and facilitate their elimination. However, this process is accompanied by collateral proinflammatory adverse effects when the NET release becomes uncontrollable, or clearance is impaired. Although NET-induced organ damage is conducted primarily and indirectly via immune complexes and the subsequent release of cytokines, their direct effects on cells are also remarkable. NETosis plays a critical pathogenic role in several renal disorders, such as the early phase of acute tubular necrosis, anti-neutrophil cytoplasmic antibody-mediated renal vasculitis, lupus nephritis, thrombotic microangiopathies, anti-glomerular basement membrane disease, and diabetic nephropathy. Their substantial contribution in the course of these disorders makes them a desirable target in the therapeutic armamentarium. This article gives an in-depth review of the heterogeneous pathogenesis and physiological regulations of NETosis and its pivotal role in renal diseases. Based on the pathogenesis, the article also outlines the current therapeutic options and possible molecular targets in the treatment of NET-related renal disorders.

Methods

We carried out thorough literature research published in PubMed and Google Scholar, including a comprehensive review and analysis of the classification, pathomechanisms, and a broad spectrum of NET-related kidney disorders.

Conclusions

NETosis plays a pivotal role in certain renal diseases. It initiates and maintains inflammatory and autoimmune disorders, thus making it a desirable target for improving patient and renal outcomes. Better understanding and clinical translation of the pathogenesis are crucial aspects to treatment, for improving patient, and renal outcomes.

Hydroxychloroquine-induced Retinal Toxicity

Long-term use of hydroxychloroquine can cause retinopathy, which may result in severe and progressive visual loss. In the past decade, hydroxychloroquine use has markedly increased and modern retinal imaging techniques have enabled the detection of early, pre-symptomatic disease. As a consequence, the prevalence of retinal toxicity in long-term hydroxychloroquine users is known to be higher than was previously estimated. The pathophysiology of the retinopathy is incompletely characterised, although significant advances have been made in understanding the disease from clinical imaging studies. Hydroxychloroquine retinopathy elicits sufficient public health concern to justify the implementation of retinopathy screening programs for patients at risk. Here, we describe the historical background of hydroxychloroquine retinopathy and summarize its current understanding. We review the utility and limitations of each of the mainstream diagnostic tests used to detect hydroxychloroquine retinopathy. The key considerations towards a consensus on the definition of hydroxychloroquine retinopathy are outlined in the context of what is known of the natural history of the disease. We compare the current screening recommendations for hydroxychloroquine retinopathy, identifying where additional evidence is required, and the management of proven cases of toxicity. Finally, we highlight the areas for further investigation, which may further reduce the risk of visual loss in hydroxychloroquine users.

Cell-free fetal DNA impairs trophoblast migration in a TLR9-dependent manner and can be reversed by hydroxychloroquine

Growing evidence suggests a relationship between elevated circulating placental-derived cell-free fetal DNA (cffDNA) and preeclampsia. Hypomethylation of CpG motifs, a hallmark of cffDNA, allows it to activate Toll-like receptor 9 (TLR9). Using an in vitro human first trimester extravillous trophoblast cell model, we sought to determine if trophoblast-derived cffDNA and ODN 2216, a synthetic unmethylated CpG oligodeoxynucleotide, directly impacted spontaneous trophoblast migration. The role of the DNA sensors TLR9, AIM2, and cGAS was assessed using the inhibitor A151. To test whether any effects could be reversed by therapeutic agents, trophoblasts were treated with or without cffDNA or ODN 2216 with or without aspirin (ASA; a known cGAS inhibitor), aspirin-triggered lipoxin (ATL), or hydroxychloroquine (HCQ; a known TLR9 inhibitor). Trophoblast-derived cffDNA and ODN 2216 reduced trophoblast migration without affecting cell viability. Reduced trophoblast migration in response to cffDNA or ODN 2216 was reversed by A151. cffDNA inhibition of trophoblast migration was reversed by HCQ, while ASA or ATL had no effect. In contrast ODN 2216 inhibition of trophoblast migration was reversed by ASA, ATL and HCQ. Our findings suggest that cffDNA can exert a local effect on placental function by impairing trophoblast migration through activation of innate immune DNA sensors. HCQ, a known TLR9 inhibitor, reversed the effects of cffDNA on trophoblast migration. Greater insights into the molecular underpinnings of how cffDNA impacts placentation can aid in our understanding of the pathogenesis of preeclampsia, and in the development of novel therapeutic approaches for preeclampsia therapy.

Salivary gland LAMP3 mRNA expression is a possible predictive marker in the response to hydroxychloroquine in Sjögren's disease

Hydroxychloroquine (HCQ) is a lysosomotropic agent that is commonly used for treating Sjögren's disease (SjD). However, its efficacy is controversial because of the divergent response to the drug among patients. In a subgroup of SjD patients, lysosome-associated membrane protein 3 (LAMP3) is elevated in expression in the salivary glands and promotes lysosomal dysregulation and lysosome-dependent apoptotic cell death. In this study, chloroquine (CQ) and its derivative HCQ were tested for their ability to prevent LAMP3-induced apoptosis, in vitro and on a mouse model of SjD. In addition, efficacy of HCQ treatment was retrospectively compared between high LAMP3 mRNA expression in minor salivary glands and those with LAMP3 mRNA levels comparable with healthy controls. Study results show that CQ treatment stabilized the lysosomal membrane in LAMP3-overexpressing cells via deactivation of cathepsin B, resulting in decreased apoptotic cell death. In mice with established SjD-like phenotype, HCQ treatment also significantly decreased apoptotic cell death and ameliorated salivary gland hypofunction. Retrospective analysis of SjD patients found that HCQ tended to be more effective in improving disease activity index, symptom severity and hypergammaglobulinemia in patients with high LAMP3 expression compared those with normal LAMP3 expression. Taken together, these findings suggested that by determining salivary gland LAMP3 mRNA level, a patient's response to HCQ treatment could be predicted. This finding may provide a novel strategy for guiding the development of more personalized medicine for SjD.

Hydroxychloroquine reduces soluble Flt-1 secretion from human cytotrophoblast, but does not mitigate markers of endothelial dysfunction in vitro

Preeclampsia is a multi-system disease that can have severe, even fatal implications for the mother and fetus. Abnormal placentation can lead to ischaemic tissue injury and placental inflammation. In turn, the placenta releases anti-angiogenic factors into the maternal circulation. These systemically act to neutralise angiogenic factors causing endothelial dysfunction causing preeclampsia. Hydroxychloroquine is an immune modulating drug that is considered safe in pregnancy. There is epidemiological evidence suggesting it may reduce the risk of preeclampsia. Here, we examined the effects hydroxychloroquine on the production and secretion of sFlt-1, soluble endoglin (sENG), placental growth factor (PlGF) and vascular endothelial growth factor (VEGF) in primary human placenta, cytotrophoblasts and umbilical vein endothelial cells (endothelial cell model). Hydroxychloroquine treatment decreased mRNA expression of two sFlt-1 isoforms and its protein secretion. sENG was not reduced. Hydroxychloroquine treatment increased secretion of pro-angiogenic factor PIGF from endothelial cells. It did not significantly reduce the expression of the endothelial cell inflammation marker, ET-1, and inflammation induced expression of the adhesion molecule, VCAM. Hydroxychloroquine could not overcome leukocyte adhesion to endothelial cells. Hydroxychloroquine mitigates features of preeclampsia, but it does not reduce key markers of endothelial dysfunction.

Translational Modeling of Chloroquine and Hydroxychloroquine Dosimetry in Human Airways for Treating Viral Respiratory Infections

Purpose

Chloroquine and hydroxychloroquine are effective against respiratory viruses in vitro. However, they lack antiviral efficacy upon oral administration. Translation of in vitro to in vivo exposure is necessary for understanding the disconnect between the two to develop effective therapeutic strategies.

Methods

We employed an in vitro ion-trapping kinetic model to predict the changes in the cytosolic and lysosomal concentrations of chloroquine and hydroxychloroquine in cell lines and primary human airway cultures. A physiologically based pharmacokinetic model with detailed respiratory physiology was used to predict regional airway exposure and optimize dosing regimens.

Results

At their reported in vitro effective concentrations in cell lines, chloroquine and hydroxychloroquine cause a significant increase in their cytosolic and lysosomal concentrations by altering the lysosomal pH. Higher concentrations of the compounds are required to achieve similar levels of cytosolic and lysosomal changes in primary human airway cells in vitro. The predicted cellular and lysosomal concentrations in the respiratory tract for in vivo oral doses are lower than the in vitro effective levels. Pulmonary administration of aerosolized chloroquine or hydroxychloroquine is predicted to achieve high bound in vitro-effective concentrations in the respiratory tract, with low systemic exposure. Achieving effective cytosolic concentrations for activating immunomodulatory effects and adequate lysosomal levels for inhibiting viral replication could be key drivers for treating viral respiratory infections.

Conclusion

Our analysis provides a framework for extrapolating in vitro effective concentrations of chloroquine and hydroxychloroquine to in vivo dosing regimens for treating viral respiratory infections.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s11095-021-03152-3.

Hydroxychloroquine inhibits the mitochondrial antioxidant system in activated T cells

Although hydroxychloroquine (HCQ) has long been used to treat autoimmune diseases, its mechanism of action remains poorly understood. In CD4 T-cells, we found that a clinically relevant concentration of HCQ inhibited the mitochondrial antioxidant system triggered by TCR crosslinking, leading to increased mitochondrial superoxide, impaired activation-induced autophagic flux, and reduced proliferation of CD4 T-cells. In antigen-presenting cells, HCQ also reduced constitutive activation of the endo-lysosomal protease legumain and toll-like receptor 9, thereby reducing cytokine production, but it had little apparent impact on constitutive antigen processing and peptide presentation. HCQ's effects did not require endo-lysosomal pH change, nor impaired autophagosome-lysosome fusion. We explored the clinical relevance of these findings in patients with celiac disease-a prototypic CD4 T-cell-mediated disease-and found that HCQ limits ex vivo antigen-specific T cell responses. We report a T-cell-intrinsic immunomodulatory effect from HCQ and suggest potential re-purposing of HCQ for celiac disease.

Risk Mitigation of Immunogenicity: A Key to Personalized Retinal Gene Therapy

Gene therapy (GT) for ocular disorders has advanced the most among adeno-associated virus (AAV)-mediated therapies, with one product already approved in the market. The bank of retinal gene mutations carefully compiled over 30 years, the small retinal surface that does not require high clinical vector stocks, and the relatively immune-privileged environment of the eye explain such success. However, adverse effects due to AAV-delivery, though rare in the retina have led to the interruption of clinical trials. Risk mitigation, as the key to safe and efficient GT, has become the focus of 'bedside-back-to-bench' studies. Herein, we overview the inflammatory adverse events described in retinal GT trials and analyze which components of the retinal immunological environment might be the most involved in these immune responses, with a focus on the innate immune system composed of microglial surveillance. We consider the factors that can influence inflammation in the retina after GT such as viral sensors in the retinal tissue and CpG content in promoters or transgene sequences. Finally, we consider options to reduce the immunological risk, including dose, modified capsids or exclusion criteria for clinical trials. A better understanding and mitigation of immune risk factors inducing host immunity in AAV-mediated retinal GT is the key to achieving safe and efficient GT.

The antimicrobial and immunomodulatory effects of Ionophores for the treatment of human infection

Ionophores are a diverse class of synthetic and naturally occurring ion transporter compounds which demonstrate both direct and in-direct antimicrobial properties against a broad panel of bacterial, fungal, viral and parasitic pathogens. In addition, ionophores can regulate the host-immune response during communicable and non-communicable disease states. Although the clinical use of ionophores such as Amphotericin B, Bedaquiline and Ivermectin highlight the utility of ionophores in modern medicine, for many other ionophore compounds issues surrounding toxicity, bioavailability or lack of in vivo efficacy studies have hindered clinical development. The antimicrobial and immunomodulating properties of a range of compounds with characteristics of ionophores remain largely unexplored. As such, ionophores remain a latent therapeutic avenue to address both the global burden of antimicrobial resistance, and the unmet clinical need for new antimicrobial therapies. This review will provide an overview of the broad-spectrum antimicrobial and immunomodulatory properties of ionophores, and their potential uses in clinical medicine for combatting infection.

The immunomodulatory effects of macrolide antibiotics in respiratory disease

Macrolide antibiotics are well known for their antibacterial properties, but extensive research in the context of inflammatory lung disease has revealed that they also have powerful immunomodulatory properties. It has been demonstrated that these drugs are therapeutically beneficial in various lung diseases, with evidence they significantly reduce exacerbations in patients with COPD, asthma, bronchiectasis and cystic fibrosis. The efficacy demonstrated in patients infected with macrolide tolerant organisms such as Pseudomonas aeruginosa supports the concept that their efficacy is at least partly related to immunomodulatory rather than antibacterial effects. Inconsistent data and an incomplete understanding of their mechanisms of action hampers the use of macrolide antibiotics as immunomodulatory therapies. Macrolides recently demonstrated no clinically relevant immunomodulatory effects in the context of COVID-19 infection. This review provides an overview of macrolide antibiotics and discusses their immunomodulatory effects and mechanisms of action in the context of inflammatory lung disease.

Autophagy in Tumor Immunity and Viral-Based Immunotherapeutic Approaches in Cancer

Autophagy is a fundamental catabolic process essential for the maintenance of cellular and tissue homeostasis, as well as directly contributing to the control of invading pathogens. Unsurprisingly, this process becomes critical in supporting cellular dysregulation that occurs in cancer, particularly the tumor microenvironments and their immune cell infiltration, ultimately playing a role in responses to cancer therapies. Therefore, understanding "cancer autophagy" could help turn this cellular waste-management service into a powerful ally for specific therapeutics. For instance, numerous regulatory mechanisms of the autophagic machinery can contribute to the anti-tumor properties of oncolytic viruses (OVs), which comprise a diverse class of replication-competent viruses with potential as cancer immunotherapeutics. In that context, autophagy can either: promote OV anti-tumor effects by enhancing infectivity and replication, mediating oncolysis, and inducing autophagic and immunogenic cell death; or reduce OV cytotoxicity by providing survival cues to tumor cells. These properties make the catabolic process of autophagy an attractive target for therapeutic combinations looking to enhance the efficacy of OVs. In this article, we review the complicated role of autophagy in cancer initiation and development, its effect on modulating OVs and immunity, and we discuss recent progress and opportunities/challenges in targeting autophagy to enhance oncolytic viral immunotherapy.

The utilization of hydroxychloroquine to reduce the main signs and symptoms of COVID-19 patients, a cross-sectional study

Hydroxychloroquine (HCQ) and chloroquine were found to have positive results in some non-randomized clinical trials with more benefit in decreasing the viral load of COVID-19. HCQ is a lysosomotropic and lipophilic drug that can penetrate cell membranes, and accumulates in the acidic lysosomes. The high concentration of alkaline HCQ increases the pH in lysosomes from the normal levels of 4.7–4.8 to 6 which leads to inhibition of lysosomes functions and thus, prevents the entry of coronavirus into cells.

Objectives

The main aim of this study is to find out the appropriateness of using HCQ in asymptomatic/mildly symptomatic COVID-19 positive patients in an attempt to reduce the development of signs and symptoms of COVID-19 and severe disease.

Methodology

Randomized selection, open-label trial to evaluate the efficacy of HCQ for patients presenting with asymptomatic COVID-19 upon diagnosis. Cases that met the inclusion criteria were divided into two arms [102 subjects to take HCQ (a loading dose of 400 mg twice daily given orally, followed by a maintenance dose of 200 mg twice daily for 4 days), and 100 subjects were used as a control group]. A follow-up for all the participants on daily basis for 14 days for any signs and symptoms (fever, cough, and shortness of breath). The main variables are action profile (represented by Area under the curve (AUC) for fever, cough, and shortness of breath statistically analyzed to differentiate between the two groups.

Results

Data in this study showed that HCQ was effective in reducing body temperature from the first day to the fifth day; this positive effect was significant with (p < 0.001) compared with subjects who didn't receive HCQ. While there was no significant effect on cough or Shortness of breath.

Conclusion

The recommendation of this study is to utilize HCQ to all subjects with asymptomatic COVID-19 infection providing that these subjects are within the inclusion criteria of this study. There was no adverse drug reaction observed for HCQ on daily follow-up.

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The debate for the use or not to use hydroxychloroquine for COVID-19 patients is still valid.

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A recommendation to utilize HCQ to all subjects with asymptomatic COVID-19 with fever.

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Utilization of HCQ should be within the inclusion criteria of this study.

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It had been noticed that there was no adverse drug reaction observed for HCQ on daily follow-up.

Inhibition of Chlamydial Infection by CRISPR/Cas9-SAM Mediated Enhancement of Human Peptidoglycan Recognition Proteins Gene Expression in HeLa Cells

The global problem of emerging resistance of microorganisms to antibiotics makes the search for new natural substances with antibacterial properties relevant. Such substances include peptidoglycan recognition proteins (PGLYRP), which are the components of the innate immunity of many organisms, including humans. These proteins have a unique mechanism of action that allows them to evade the resistance of bacteria to them, as well as to be active against both Gram-positive and Gram-negative bacteria. However, the use of antimicrobial recombinant proteins is not always advisable due to the complexity of local delivery of the proteins and their stability; in this regard it seems appropriate to activate the components of the innate immunity. The aim of this study was to increase the expression level of native peptidoglycan recognition protein genes in HeLa cells using genome-editing technology with synergistic activation mediators (CRISPR/Cas9-SAM) and evaluate antichlamydial effect of PGLYRP. We demonstrated activation of the chlamydial two-component gene system (ctcB-ctcC), which played a key role in the mechanism of action of the peptidoglycan recognition proteins. We generated the HeLa cell line transduced with lentiviruses encoding CRISPR/Cas9-SAM activation system with increased PGLYRP gene expression. It was shown that activation of the own peptidoglycan recognition proteins gene expression in the cell line caused inhibition of the chlamydial infection development. The proposed approach makes it possible to use the capabilities of innate immunity to combat infectious diseases caused by Gram-positive and Gram-negative bacteria.

The Rise and Fall of Chloroquine/Hydroxychloroquine as Compassionate Therapy of COVID-19

The emergence and rapid spread of novel coronavirus disease (COVID-19) has posed a serious challenge to global public health in 2020. The speed of this viral spread together with the high mortality rate has caused an unprecedented public health crisis. With no antivirals or vaccines available for the treatment of COVID-19, the medical community is presently exploring repositioning of clinically approved drugs for COVID-19. Chloroquine (CQ) and hydroxychloroquine (HCQ) have emerged as potential candidates for repositioning as anti-COVID-19 therapeutics and have received FDA authorization for compassionate use in COVID-19 patients. On March 28, 2020, the U.S. Food and Drug Administration (FDA) issued an Emergency Use Authorization (EUA) for HCQ in the treatment of COVID-19. However, it was later revoked by the FDA on June 15, 2020, after analyzing the emerging scientific data from ongoing clinical trials. Similarly, the World Health Organization (WHO) also conducted a Solidarity trial of chloroquine, hydroxychloroquine, remdesivir, lopinavir, and ritonavir. However, on May 23, 2020, the executive body of the "Solidarity trial" decided to put a temporary hold on the HCQ trial. On June 17, 2020, the WHO abruptly stopped the Solidarity trial of HCQ. The current review strives to examine the basis of compassionate use of CQ and HCQ for the treatment of COVID-19 in terms of literature evidence, establishing the antiviral efficacy of these drugs against corona and related viruses. Furthermore, the review presents a critical analysis of the clinical trial findings and also provides an insight into the dynamically changing decision on the authorization and withdrawal of HCQ as anti-COVID-19 therapy by the U.S. FDA and the WHO. Ultimately, our study necessitates an evidenced-based treatment protocol to confront the ongoing COVID-19 pandemic and not the mere observational study that mislead the public healthcare system, which paralyzes the entire world.

Overcoming Chemoresistance: Altering pH of Cellular Compartments by Chloroquine and Hydroxychloroquine

Resistance to the anti-cancer effects of chemotherapeutic agents (chemoresistance) is a major issue for people living with cancer and their providers. A diverse set of cellular and inter-organellar signaling changes have been implicated in chemoresistance, but it is still unclear what processes lead to chemoresistance and effective strategies to overcome chemoresistance are lacking. The anti-malaria drugs, chloroquine (CQ) and its derivative hydroxychloroquine (HCQ) are being used for the treatment of various cancers and CQ and HCQ are used in combination with chemotherapeutic drugs to enhance their anti-cancer effects. The widely accepted anti-cancer effect of CQ and HCQ is their ability to inhibit autophagic flux. As diprotic weak bases, CQ and HCQ preferentially accumulate in acidic organelles and neutralize their luminal pH. In addition, CQ and HCQ acidify the cytosolic and extracellular environments; processes implicated in tumorigenesis and cancer. Thus, the anti-cancer effects of CQ and HCQ extend beyond autophagy inhibition. The present review summarizes effects of CQ, HCQ and proton pump inhibitors on pH of various cellular compartments and discuss potential mechanisms underlying their pH-dependent anti-cancer effects. The mechanisms considered here include their ability to de-acidify lysosomes and inhibit autophagosome lysosome fusion, to de-acidify Golgi apparatus and secretory vesicles thus affecting secretion, and to acidify cytoplasm thus disturbing aerobic metabolism. Further, we review the ability of these agents to prevent chemotherapeutic drugs from accumulating in acidic organelles and altering their cytosolic concentrations.