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Kumar A, Sharma A, Tirpude NV, Padwad Y, Hallan V, Kumar S. Plant-derived immuno-adjuvants in vaccines formulation: a promising avenue for improving vaccines efficacy against SARS-CoV-2 virus. Pharmacol Rep 2022; 74:1238-1254. [PMID: 36125739 PMCID: PMC9487851 DOI: 10.1007/s43440-022-00418-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 09/08/2022] [Accepted: 09/09/2022] [Indexed: 12/13/2022]
Abstract
The SARS-CoV-2 outbreak has posed a plethora of problems for the global healthcare system and socioeconomic burden. Despite valiant efforts to contain the COVID-19 outbreak, the situation has deteriorated to the point that there are no viable preventive therapies to treat this disease. The case count has skyrocketed globally due to the newly evolved variants. Despite vaccination drives, the re-occurrence of recent pandemic waves has reinforced the importance of innovation/utilization of immune-booster to achieve appropriate long-term vaccine protection. Plant-derived immuno-adjuvants, which have multifaceted functions, can impede infections by boosting the immune system. Many previous studies have shown that formulation of vaccines using plant-derived adjuvant results in long-lasting immunity may overcome the natural tendency of coronavirus immunity to wane quickly. Plant polysaccharides, glycosides, and glycoprotein extracts have reportedly been utilized as enticing adjuvants in experimental vaccines, such as Advax, Matrix-M, and Mistletoe lectin, which have been shown to be highly immunogenic and safe. When employed in vaccine formulation, Advax and Matrix-M generate long-lasting antibodies, a balanced robust Th1/Th2 cytokine profile, and the stimulation of cytotoxic T cells. Thus, the use of adjuvants derived from plants may increase the effectiveness of vaccines, resulting in the proper immunological response required to combat COVID-19. A few have been widely used in epidemic outbreaks, including SARS and H1N1 influenza, and their use could also improve the efficacy of COVID-19 vaccines. In this review, the immunological adjuvant properties of plant compounds as well as their potential application in anti-COVID-19 therapy are thoroughly discussed.
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Affiliation(s)
- Arbind Kumar
- grid.417640.00000 0004 0500 553XCOVID-19 Testing facility, CSIR-Institute of Himalayan Bioresource Technology (IHBT), Palampur, India
| | - Aashish Sharma
- grid.417640.00000 0004 0500 553XCOVID-19 Testing facility, CSIR-Institute of Himalayan Bioresource Technology (IHBT), Palampur, India
| | - Narendra Vijay Tirpude
- grid.417640.00000 0004 0500 553XDietetics and Nutrition Technology Division, CSIR-Institute of Himalayan Bioresource Technology (IHBT), Palampur, India
| | - Yogendra Padwad
- grid.417640.00000 0004 0500 553XDietetics and Nutrition Technology Division, CSIR-Institute of Himalayan Bioresource Technology (IHBT), Palampur, India
| | - Vipin Hallan
- grid.417640.00000 0004 0500 553XBiotechnology Division, CSIR-Institute of Himalayan Bioresource Technology (IHBT), Palampur, India
| | - Sanjay Kumar
- grid.417640.00000 0004 0500 553XCSIR-Institute of Himalayan Bioresource Technology (IHBT), Palampur, India
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Naghipour S, Ghodousi M, Rahsepar S, Elyasi S. Repurposing of well-known medications as antivirals: hydroxychloroquine and chloroquine - from HIV-1 infection to COVID-19. Expert Rev Anti Infect Ther 2020; 18:1119-1133. [PMID: 32631083 DOI: 10.1080/14787210.2020.1792291] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
INTRODUCTION Chloroquine (CQ) and hydroxychloroquine (HCQ) originally were prescribed for prevention or treatment of malaria, but now successfully are used in several rheumatologic diseases. In addition, in recent decades considering their immunomodulatory effects, high tolerably, and low cost, they are evaluated for various viral infections from HIV to COVID-19. AREAS COVERED In this review, we tried to summarize all available studies on HCQ and CQ efficacy for management of viral infections and the probable mechanisms of action. The data were collected by searching 'Hydroxychloroquine,' 'Chloroquine,' 'Viral infection,' and names of various viral infections in PubMed/MEDLINE, Scopus, and Google Scholar databases from commencement to June 2020. Out of 95 search results, 74 most relevant works were gathered. EXPERT OPINION HCQ/CQ showed acceptable efficacy in HIV especially as an adjuvant treatment beside routine HAART. However, for some viral infections such as ZIKA, EBOLA, SARS-CoV, and MERS-CoV, human studies are lacking. In the COVID-19 pandemic, in vitro and preliminary human studies showed encouraging findings. However, later well-designed trials and retrospective studies with large sample size not only reported non-significant efficacy but also showed more cardiac adverse reactions. Alkalinization of acid vesicles is the most important mechanism of action.
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Affiliation(s)
- Sara Naghipour
- Department of Clinical Pharmacy, School of Pharmacy, Mashhad University of Medical Sciences , Mashhad, Iran
| | - Mahsa Ghodousi
- Department of Clinical Pharmacy, School of Pharmacy, Mashhad University of Medical Sciences , Mashhad, Iran
| | - Sara Rahsepar
- Department of Clinical Pharmacy, School of Pharmacy, Mashhad University of Medical Sciences , Mashhad, Iran
| | - Sepideh Elyasi
- Department of Clinical Pharmacy, School of Pharmacy, Mashhad University of Medical Sciences , Mashhad, Iran
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Al-Bari AA. Facts and Myths: Efficacies of Repurposing Chloroquine and Hydroxychloroquine for the Treatment of COVID-19. Curr Drug Targets 2020; 21:1703-1721. [PMID: 32552642 DOI: 10.2174/1389450121666200617133142] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 05/22/2020] [Accepted: 06/08/2020] [Indexed: 02/06/2023]
Abstract
The emergence of coronavirus disease 2019 (COVID-19) is caused by the 2019 novel coronavirus (2019-nCoV). The 2019-nCoV first broke out in Wuhan and subsequently spread worldwide owing to its extreme transmission efficiency. The fact that the COVID-19 cases and mortalities are reported globally and the WHO has declared this outbreak as the pandemic, the international health authorities have focused on rapid diagnosis and isolation of patients as well as search for therapies able to counter the disease severity. Due to the lack of known specific, effective and proven therapies as well as the situation of public-health emergency, drug repurposing appears to be the best armour to find a therapeutic solution against 2019-nCoV infection. Repurposing anti-malarial drugs and chloroquine (CQ)/ hydroxychloroquine (HCQ) have shown efficacy to inhibit most coronaviruses, including SARS-CoV-1 coronavirus. These CQ analogues have shown potential efficacy to inhibit 2019-nCoV in vitro that leads to focus several future clinical trials. This review discusses the possible effective roles and mechanisms of CQ analogues for interfering with the 2019-nCoV replication cycle and infection.
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Affiliation(s)
- Abdul Alim Al-Bari
- Department of Pharmacy, University of Rajshahi, Rajshahi-6205, Bangladesh
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Tripathy S, Dassarma B, Roy S, Chabalala H, Matsabisa MG. A review on possible modes of action of chloroquine/hydroxychloroquine: repurposing against SAR-CoV-2 (COVID-19) pandemic. Int J Antimicrob Agents 2020; 56:106028. [PMID: 32450198 PMCID: PMC7243790 DOI: 10.1016/j.ijantimicag.2020.106028] [Citation(s) in RCA: 74] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 05/14/2020] [Accepted: 05/17/2020] [Indexed: 12/12/2022]
Abstract
Chloroquine (CQ) has diverse modes of action against viral infections. CQ may interfere with SARS-CoV-2 attachment to the host ACE2 receptor. CQ may hamper the STING pathway to attenuate the pro-inflammatory response. Hydroxychloroquine (HCQ) might be a logical approach in the treatment of SARS-CoV-2 infection. Large clinical trials are needed before clinical recommendations of HCQ against COVID-19.
Chloroquine (CQ) and its analogue hydroxychloroquine (HCQ) have long been used worldwide as frontline drugs for the treatment and prophylaxis of human malaria. Since the first reported cases in Wuhan, China, in late December 2019, humans have been under threat from coronavirus disease 2019 (COVID-19) caused by the novel coronavirus SARS-CoV-2 (previously known as 2019-nCoV), subsequently declared a pandemic. While the world is searching for expedited approval for a vaccine, which may be only preventative and not a cure, physicians and country leaders are considering several concerted clinical trials suggesting that the age-old antimalarial drugs CQ/HCQ could be a potent therapeutic against COVID-19. Based on accumulating scientific reports, here we highlight the possible modes of action of CQ/HCQ that could justify its use against viral infections. Considering the global health crisis of the COVID-19 pandemic, the option of repurposing old drugs, e.g. CQ/HCQ, particularly HCQ, for the treatment of SARS-CoV-2 infection could be a good choice. CQ/HCQ has diverse modes of action, including alteration of the acidic environment inside lysosomes and late endosomes, preventing endocytosis, exosome release and phagolysosomal fusion, and inhibition of the host cytokine storm. One or more diverse mechanisms might work against viral infections and reduce mortality. As there is no cure for COVID-19, clinical testing of HCQ is urgently required to determine its potency against SARS-CoV-2, as this is the currently available treatment option. There remains a need to find other innovative drug candidates as possible candidates to enter clinical evaluation and testing.
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Affiliation(s)
- Satyajit Tripathy
- Department of Pharmacology, School of Medicine, Faculty of Health Sciences, University of the Free State, Bloemfontein 9300, South Africa
| | - Barsha Dassarma
- Department of Pharmacology, School of Medicine, Faculty of Health Sciences, University of the Free State, Bloemfontein 9300, South Africa
| | - Somenath Roy
- Ex-Professor, Department of Human Physiology with Community Health, Vidyasagar University, Paschim Medinipur 721102, India
| | - Hlupheka Chabalala
- IK-based Technology Innovations, Department of Science and Innovations, Brummeria, Pretoria 0001, South Africa
| | - Motlalepula Gilbert Matsabisa
- Department of Pharmacology, School of Medicine, Faculty of Health Sciences, University of the Free State, Bloemfontein 9300, South Africa.
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Lacaille-Dubois MA. Updated insights into the mechanism of action and clinical profile of the immunoadjuvant QS-21: A review. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2019; 60:152905. [PMID: 31182297 PMCID: PMC7127804 DOI: 10.1016/j.phymed.2019.152905] [Citation(s) in RCA: 95] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 03/26/2019] [Accepted: 03/30/2019] [Indexed: 05/06/2023]
Abstract
BACKGROUND Vaccine adjuvants are compounds that significantly enhance/prolong the immune response to a co-administered antigen. The limitations of the use of aluminium salts that are unable to elicite cell responses against intracellular pathogens such as those causing malaria, tuberculosis, or AIDS, have driven the development of new alternative adjuvants such as QS-21, a triterpene saponin purified from Quillaja saponaria. PURPOSE The aim of this review is to attempt to clarify the mechanism of action of QS-21 through either receptors or signaling pathways in vitro and in vivo with special emphasis on the co-administration with other immunostimulants in new adjuvant formulations, called adjuvant systems (AS). Furthermore, the most relevant clinical applications will be presented. METHODS A literature search covering the period 2014-2018 was performed using electronic databases from Sci finder, Science direct, Medline/Pubmed, Scopus, Google scholar. RESULTS Insights into the mechanism of action of QS-21 can be summarized as follows: 1) in vivo stimulation of Th2 humoral and Th1 cell-mediated immune responses through action on antigen presenting cells (APCs) and T cells, leading to release of Th1 cytokines participating in the elimination of intracellular pathogens. 2) activation of the NLRP3 inflammasome in mouse APCs with subsequent release of caspase-1 dependent cytokines, Il-1β and Il-18, important for Th1 responses. 3) synthesis of nearly 50 QS-21 analogs, allowing structure/activity relationships and mechanistic studies. 4) unique synergy mechanism between monophosphoryl lipid A (MPL A) and QS-21, formulated in a liposome (AS01) in the early IFN-γ response, promoting vaccine immunogenicity. The second part of the review is related to phase I-III clinical trials of QS-21, mostly formulated in ASs, to evaluate efficacy, immunogenicity and safety of adjuvanted prophylactic vaccines against infectious diseases, e.g. malaria, herpes zoster, tuberculosis, AIDS and therapeutic vaccines against cancer and Alzheimer's disease. CONCLUSION The most advanced phase III clinical applications led to the development of two vaccines containing QS-21 as part of the AS, the Herpes Zoster vaccine (HZ/su) (Shingrix™) which received a license in 2017 from the FDA and a marketing authorization in the EU in 2018 and the RTS,S/AS01 vaccine (Mosquirix™) against malaria, which was approved by the EMA in 2015 for further implementation in Sub-Saharan countries for routine use.
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Affiliation(s)
- Marie-Aleth Lacaille-Dubois
- PEPITE EA 4267, Université de Bourgogne Franche-Comté, Laboratoire de Pharmacognosie, UFR des Sciences de Santé, 7, Bd Jeanne d'Arc, 21079 Dijon Cedex, France.
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Munusamy Ponnan S, Pattabiram S, Thiruvengadam K, Goyal R, Singla N, Mukherjee J, Chatrath S, Bergin P, T. Kopycinski J, Gilmour J, Kumar S, Muthu M, Subramaniam S, Swaminathan S, Prasad Tripathy S, Luke HE. Induction and maintenance of bi-functional (IFN-γ + IL-2+ and IL-2+ TNF-α+) T cell responses by DNA prime MVA boosted subtype C prophylactic vaccine tested in a Phase I trial in India. PLoS One 2019; 14:e0213911. [PMID: 30921340 PMCID: PMC6438518 DOI: 10.1371/journal.pone.0213911] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Accepted: 03/04/2019] [Indexed: 01/09/2023] Open
Abstract
Effective vaccine design relies on accurate knowledge of protection against a pathogen, so as to be able to induce relevant and effective protective responses against it. An ideal Human Immunodeficiency virus (HIV) vaccine should induce humoral as well as cellular immune responses to prevent initial infection of host cells or limit early events of viral dissemination. A Phase I HIV-1 prophylactic vaccine trial sponsored by the International AIDS Vaccine Initiative (IAVI) was conducted in India in 2009.The trial tested a HIV-1 subtype C vaccine in a prime-boost regimen, comprising of a DNA prime (ADVAX) and Modified Vaccine Ankara (MVA) (TBC-M4) boost. The trial reported that the vaccine regimen was safe, well tolerated, and resulted in enhancement of HIV-specific immune responses. However, preliminary immunological studies were limited to vaccine-induced IFN-γ responses against the Env and Gag peptides. The present study is a retrospective study to characterize in detail the nature of the vaccine-induced cell mediated immune responses among volunteers, using Peripheral Blood Mononuclear Cells (PBMC) that were archived during the trial. ELISpot was used to measure IFN-γ responses and polyfunctional T cells were analyzed by intracellular multicolor flow cytometry. It was observed that DNA priming and MVA boosting induced Env and Gag specific bi-functional and multi-functional CD4+ and CD8+ T cells expressing IFN-γ, TNF-α and IL-2. The heterologous prime-boost regimen appeared to be slightly superior to the homologous prime-boost regimen in inducing favorable cell mediated immune responses. These results suggest that an in-depth analysis of vaccine-induced cellular immune response can aid in the identification of correlates of an effective immunogenic response, and inform future design of HIV vaccines.
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Affiliation(s)
- Sivasankaran Munusamy Ponnan
- Department of HIV, National Institute for Research in Tuberculosis (Indian Council of Medical Research), Chennai, India
| | - Sathyamurthy Pattabiram
- Department of HIV, National Institute for Research in Tuberculosis (Indian Council of Medical Research), Chennai, India
| | - Kannan Thiruvengadam
- Department of HIV, National Institute for Research in Tuberculosis (Indian Council of Medical Research), Chennai, India
| | - Rajat Goyal
- International AIDS Vaccine Initiative, New Delhi, India
| | - Nikhil Singla
- International AIDS Vaccine Initiative, New Delhi, India
| | | | | | - Philip Bergin
- IAVI Human Immunology Laboratory, Imperial College, London, United Kingdom
| | | | - Jill Gilmour
- IAVI Human Immunology Laboratory, Imperial College, London, United Kingdom
| | - Sriram Kumar
- Department of HIV, National Institute for Research in Tuberculosis (Indian Council of Medical Research), Chennai, India
| | - Malathy Muthu
- Department of HIV, National Institute for Research in Tuberculosis (Indian Council of Medical Research), Chennai, India
| | - Sudha Subramaniam
- Department of HIV, National Institute for Research in Tuberculosis (Indian Council of Medical Research), Chennai, India
| | - Soumya Swaminathan
- Department of HIV, National Institute for Research in Tuberculosis (Indian Council of Medical Research), Chennai, India
| | - Srikanth Prasad Tripathy
- Department of HIV, National Institute for Research in Tuberculosis (Indian Council of Medical Research), Chennai, India
| | - Hanna Elizabeth Luke
- Department of HIV, National Institute for Research in Tuberculosis (Indian Council of Medical Research), Chennai, India
- * E-mail:
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Al-Bari MAA. Targeting endosomal acidification by chloroquine analogs as a promising strategy for the treatment of emerging viral diseases. Pharmacol Res Perspect 2017; 5:e00293. [PMID: 28596841 PMCID: PMC5461643 DOI: 10.1002/prp2.293] [Citation(s) in RCA: 241] [Impact Index Per Article: 34.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2016] [Revised: 11/15/2016] [Accepted: 12/07/2016] [Indexed: 12/13/2022] Open
Abstract
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.
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Welsby I, Detienne S, N'Kuli F, Thomas S, Wouters S, Bechtold V, De Wit D, Gineste R, Reinheckel T, Elouahabi A, Courtoy PJ, Didierlaurent AM, Goriely S. Lysosome-Dependent Activation of Human Dendritic Cells by the Vaccine Adjuvant QS-21. Front Immunol 2017; 7:663. [PMID: 28105029 PMCID: PMC5215313 DOI: 10.3389/fimmu.2016.00663] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Accepted: 12/16/2016] [Indexed: 12/12/2022] Open
Abstract
The adjuvant properties of the saponin QS-21 have been known for decades. It is a component of the Adjuvant System AS01 that is used in several vaccine candidates. QS-21 strongly potentiates both cellular and humoral immune responses to purified antigens, yet how it activates immune cells is largely unknown. Here, we report that QS-21 directly activated human monocyte-derived dendritic cells (moDCs) and promoted a pro-inflammatory transcriptional program. Cholesterol-dependent QS-21 endocytosis followed by lysosomal destabilization and Syk kinase activation were prerequisites for this response. Cathepsin B, a lysosomal cysteine protease, was essential for moDC activation in vitro and contributed to the adjuvant effects of QS-21 in vivo. Collectively, these findings provide new insights into the pathways involved in the direct activation of antigen-presenting cells by a clinically relevant QS-21 formulation.
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Affiliation(s)
- Iain Welsby
- Institute for Medical Immunology, Université Libre de Bruxelles (ULB) , Gosselies , Belgium
| | - Sophie Detienne
- Institute for Medical Immunology, Université Libre de Bruxelles (ULB) , Gosselies , Belgium
| | - Francisca N'Kuli
- Cell Biology Unit, de Duve Institute, Université Catholique de Louvain , Brussels , Belgium
| | - Séverine Thomas
- Institute for Medical Immunology, Université Libre de Bruxelles (ULB) , Gosselies , Belgium
| | | | | | - Dominique De Wit
- Institute for Medical Immunology, Université Libre de Bruxelles (ULB) , Gosselies , Belgium
| | | | - Thomas Reinheckel
- Medical Faculty, Institute for Molecular Medicine and Cell Research, Albert Ludwigs University , Freiburg , Germany
| | | | - Pierre J Courtoy
- Cell Biology Unit, de Duve Institute, Université Catholique de Louvain , Brussels , Belgium
| | | | - Stanislas Goriely
- Institute for Medical Immunology, Université Libre de Bruxelles (ULB) , Gosselies , Belgium
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Lorin C, Vanloubbeeck Y, Baudart S, Ska M, Bayat B, Brauers G, Clarinval G, Donner MN, Marchand M, Koutsoukos M, Mettens P, Cohen J, Voss G. Heterologous prime-boost regimens with a recombinant chimpanzee adenoviral vector and adjuvanted F4 protein elicit polyfunctional HIV-1-specific T-Cell responses in macaques. PLoS One 2015; 10:e0122835. [PMID: 25856308 PMCID: PMC4391709 DOI: 10.1371/journal.pone.0122835] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Accepted: 02/15/2015] [Indexed: 01/04/2023] Open
Abstract
HIV-1-specific CD4+ and CD8+ T lymphocytes are important for HIV-1 replication control. F4/AS01 consists of F4 recombinant fusion protein (containing clade B Gag/p24, Pol/RT, Nef and Gag/p17) formulated in AS01 Adjuvant System, and was shown to induce F4-specific polyfunctional CD4+ T-cell responses in humans. While replication-incompetent recombinant HIV-1/SIV antigen-expressing human adenoviral vectors can elicit high-frequency antigen-specific CD8+ T-cell responses, their use is hampered by widespread pre-existing immunity to human serotypes. Non-human adenovirus serotypes associated with lower prevalence may offer an alternative strategy. We evaluated the immunogenicity of AdC7-GRN ('A'), a recombinant chimpanzee adenovirus type 7 vector expressing clade B Gag, RT and Nef, and F4/AS01 ('P'), when delivered intramuscularly in homologous (PP or AA) and heterologous (AAPP or PPAA) prime-boost regimens, in macaques and mice. Vaccine-induced HIV-1-antigen-specific T cells in peripheral blood (macaques), liver, spleen, and intestinal and genital mucosa (mice) were characterized by intracellular cytokine staining. Vaccine-specific IgG antibodies (macaques) were detected using ELISA. In macaques, only the heterologous prime-boost regimens induced polyfunctional, persistent and balanced CD4+ and CD8+ T-cell responses specific to each HIV-1 vaccine antigen. AdC7-GRN priming increased the polyfunctionality of F4/AS01-induced CD4+ T cells. Approximately 50% of AdC7-GRN-induced memory CD8+ T cells exhibited an effector-memory phenotype. HIV-1-specific antibodies were detected with each regimen. In mice, antigen-specific CD4+ and CD8+ T-cell responses were detected in the mucosal and systemic anatomical compartments assessed. When administered in heterologous prime-boost regimens, AdC7-GRN and F4/AS01 candidate vaccines acted complementarily in inducing potent and persistent peripheral blood HIV-1-specific CD4+ and CD8+ T-cell responses and antibodies in macaques. Besides, adenoviral vector priming modulated the cytokine-expression profile of the protein-induced CD4+ T cells. Each regimen induced HIV-1-specific T-cell responses in systemic/local tissues in mice. This suggests that prime-boost regimens combining adjuvanted protein and low-seroprevalent chimpanzee adenoviral vectors represent an attractive vaccination strategy for clinical evaluation.
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Moses T, Papadopoulou KK, Osbourn A. Metabolic and functional diversity of saponins, biosynthetic intermediates and semi-synthetic derivatives. Crit Rev Biochem Mol Biol 2014; 49:439-62. [PMID: 25286183 PMCID: PMC4266039 DOI: 10.3109/10409238.2014.953628] [Citation(s) in RCA: 238] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 08/01/2014] [Accepted: 08/07/2014] [Indexed: 01/11/2023]
Abstract
Saponins are widely distributed plant natural products with vast structural and functional diversity. They are typically composed of a hydrophobic aglycone, which is extensively decorated with functional groups prior to the addition of hydrophilic sugar moieties, to result in surface-active amphipathic compounds. The saponins are broadly classified as triterpenoids, steroids or steroidal glycoalkaloids, based on the aglycone structure from which they are derived. The saponins and their biosynthetic intermediates display a variety of biological activities of interest to the pharmaceutical, cosmetic and food sectors. Although their relevance in industrial applications has long been recognized, their role in plants is underexplored. Recent research on modulating native pathway flux in saponin biosynthesis has demonstrated the roles of saponins and their biosynthetic intermediates in plant growth and development. Here, we review the literature on the effects of these molecules on plant physiology, which collectively implicate them in plant primary processes. The industrial uses and potential of saponins are discussed with respect to structure and activity, highlighting the undoubted value of these molecules as therapeutics.
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Affiliation(s)
- Tessa Moses
- Department of Metabolic Biology, John Innes CentreColney Lane, NorwichUK
| | | | - Anne Osbourn
- Department of Metabolic Biology, John Innes CentreColney Lane, NorwichUK
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