1
|
Devaux CA, Melenotte C, Piercecchi-Marti MD, Delteil C, Raoult D. Cyclosporin A: A Repurposable Drug in the Treatment of COVID-19? Front Med (Lausanne) 2021; 8:663708. [PMID: 34552938 PMCID: PMC8450353 DOI: 10.3389/fmed.2021.663708] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 08/04/2021] [Indexed: 12/22/2022] Open
Abstract
Coronavirus disease 2019 (COVID-19) is now at the forefront of major health challenge faced globally, creating an urgent need for safe and efficient therapeutic strategies. Given the high attrition rates, high costs, and quite slow development of drug discovery, repurposing of known FDA-approved molecules is increasingly becoming an attractive issue in order to quickly find molecules capable of preventing and/or curing COVID-19 patients. Cyclosporin A (CsA), a common anti-rejection drug widely used in transplantation, has recently been shown to exhibit substantial anti-SARS-CoV-2 antiviral activity and anti-COVID-19 effect. Here, we review the molecular mechanisms of action of CsA in order to highlight why this molecule seems to be an interesting candidate for the therapeutic management of COVID-19 patients. We conclude that CsA could have at least three major targets in COVID-19 patients: (i) an anti-inflammatory effect reducing the production of proinflammatory cytokines, (ii) an antiviral effect preventing the formation of the viral RNA synthesis complex, and (iii) an effect on tissue damage and thrombosis by acting against the deleterious action of angiotensin II. Several preliminary CsA clinical trials performed on COVID-19 patients report lower incidence of death and suggest that this strategy should be investigated further in order to assess in which context the benefit/risk ratio of repurposing CsA as first-line therapy in COVID-19 is the most favorable.
Collapse
Affiliation(s)
- Christian A. Devaux
- Aix-Marseille Univ, IRD, APHM, MEPHI, IHU-Méditerranée Infection, Marseille, France
- CNRS, Marseille, France
| | - Cléa Melenotte
- Aix-Marseille Univ, IRD, APHM, MEPHI, IHU-Méditerranée Infection, Marseille, France
| | - Marie-Dominique Piercecchi-Marti
- Department of Legal Medicine, Hôpital de la Timone, Marseille University Hospital Center, Marseille, France
- Aix Marseille Univ, CNRS, EFS, ADES, Marseille, France
| | - Clémence Delteil
- Department of Legal Medicine, Hôpital de la Timone, Marseille University Hospital Center, Marseille, France
- Aix Marseille Univ, CNRS, EFS, ADES, Marseille, France
| | - Didier Raoult
- Aix-Marseille Univ, IRD, APHM, MEPHI, IHU-Méditerranée Infection, Marseille, France
| |
Collapse
|
2
|
Zhang Y, Jiang T, Li A, Li Z, Hou J, Gao M, Huang X, Su B, Wu H, Zhang T, Jiang W. Adjunct Therapy for CD4 + T-Cell Recovery, Inflammation and Immune Activation in People Living With HIV: A Systematic Review and Meta-Analysis. Front Immunol 2021; 12:632119. [PMID: 33679779 PMCID: PMC7925844 DOI: 10.3389/fimmu.2021.632119] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Accepted: 01/22/2021] [Indexed: 01/21/2023] Open
Abstract
Background: HIV infection results in immune homeostasis perturbations, which is characterized by CD4+ T-cell depletion, immune activation, and inflammation. Effective antiretroviral therapy (ART) does not fully restore immunologic and clinical health in people living with HIV (PLWH). Various drugs have been used to improve their immune status and CD4+ T-cell counts, but no measures have been tested effective. Here we conduct a systematic review and meta-analysis of existing clinical studies on improving CD4+ T-cell count while decreasing inflammation and immune activation. Methods: We retrieved possible relevant publications from a total of five electronic databases and selected eligible studies, which dealt with outcomes of medical therapy for CD4+ T-cell count recovery, inflammation, and immune activation with or without ART. We paid particular attention to immunologic non-responders with a favorable treatment regimen. Results: Thirty-three articles were included in the systematic review and meta-analysis. However, there were no safe and effective medications specific for improving CD4+ T-cell reconstitution. The immunological benefits or adverse events mainly depend on the safety, dosage, and duration of the candidate medication use, as well as whether it is combined with ART. Conclusion: Under the “safe, combined, adequate and long (SCAL)” principles, alternative approaches are needed to accelerate the recovery of CD4+ T-cells, and to prevent adverse long-term outcomes in PLWH with standard ART treatment.
Collapse
Affiliation(s)
- Yang Zhang
- Center for Infectious Diseases, Beijing YouAn Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of AIDS Research, Beijing, China.,Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC, United States
| | - Taiyi Jiang
- Center for Infectious Diseases, Beijing YouAn Hospital, Capital Medical University, Beijing, China
| | - Aixin Li
- Center for Infectious Diseases, Beijing YouAn Hospital, Capital Medical University, Beijing, China
| | - Zhen Li
- Center for Infectious Diseases, Beijing YouAn Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of AIDS Research, Beijing, China
| | - Jianhua Hou
- Center for Infectious Diseases, Beijing YouAn Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of AIDS Research, Beijing, China
| | - Meixia Gao
- Center for Infectious Diseases, Beijing YouAn Hospital, Capital Medical University, Beijing, China
| | - Xiaojie Huang
- Center for Infectious Diseases, Beijing YouAn Hospital, Capital Medical University, Beijing, China
| | - Bin Su
- Center for Infectious Diseases, Beijing YouAn Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of AIDS Research, Beijing, China
| | - Hao Wu
- Center for Infectious Diseases, Beijing YouAn Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of AIDS Research, Beijing, China
| | - Tong Zhang
- Center for Infectious Diseases, Beijing YouAn Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of AIDS Research, Beijing, China
| | - Wei Jiang
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC, United States.,Division of Infectious Diseases, Department of Medicine, Medical University of South Carolina, Charleston, SC, United States
| |
Collapse
|
3
|
Kong Y, Tian Y, Hao Y, Chong X, Xiao J, Yang D, Song C, Han J, Dai G, Zhang F, Zheng H, Zhao H, Zeng H. Two types of poor immunological responder showing distinct responses to long-term HAART. Int J Infect Dis 2019; 86:178-187. [PMID: 31398453 DOI: 10.1016/j.ijid.2019.07.037] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 07/29/2019] [Accepted: 07/31/2019] [Indexed: 12/19/2022] Open
Abstract
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.
Collapse
Affiliation(s)
- Yaxian Kong
- Institute of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing, China; Beijing Key Laboratory of Emerging Infectious Diseases, Beijing, China
| | - Yunfei Tian
- Clinical and Research Center of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing, China
| | - Yu Hao
- Institute of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing, China; Beijing Key Laboratory of Emerging Infectious Diseases, Beijing, China
| | - Xuejing Chong
- Clinical and Research Center of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing, China
| | - Jiang Xiao
- Clinical and Research Center of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing, China
| | - Di Yang
- Clinical and Research Center of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing, China
| | - Chuan Song
- Institute of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing, China; Beijing Key Laboratory of Emerging Infectious Diseases, Beijing, China
| | - Junyan Han
- Institute of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing, China; Beijing Key Laboratory of Emerging Infectious Diseases, Beijing, China
| | - Guorui Dai
- Clinical and Research Center of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing, China
| | - Fujie Zhang
- Clinical and Research Center of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing, China
| | - Hong Zheng
- Penn State Hershey Cancer Institute, Penn State University College of Medicine, Hershey, PA, USA
| | - Hongxin Zhao
- Clinical and Research Center of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing, China.
| | - Hui Zeng
- Institute of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing, China; Beijing Key Laboratory of Emerging Infectious Diseases, Beijing, China.
| |
Collapse
|
4
|
Jean MJ, Fiches G, Hayashi T, Zhu J. Current Strategies for Elimination of HIV-1 Latent Reservoirs Using Chemical Compounds Targeting Host and Viral Factors. AIDS Res Hum Retroviruses 2019; 35:1-24. [PMID: 30351168 DOI: 10.1089/aid.2018.0153] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Since the implementation of combination antiretroviral therapy (cART), rates of HIV type 1 (HIV-1) mortality, morbidity, and newly acquired infections have decreased dramatically. In fact, HIV-1-infected individuals under effective suppressive cART approach normal life span and quality of life. However, long-term therapy is required because the virus establish a reversible state of latency in memory CD4+ T cells. Two principle strategies, namely "shock and kill" approach and "block and lock" approach, are currently being investigated for the eradication of these HIV-1 latent reservoirs. Actually, both of these contrasting approaches are based on the use of small-molecule compounds to achieve the cure for HIV-1. In this review, we discuss the recent progress that has been made in designing and developing small-molecule compounds for both strategies.
Collapse
Affiliation(s)
- Maxime J. Jean
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, New York
| | - Guillaume Fiches
- Department of Pathology, The Ohio State University Wexner Medical Center, Columbus, Ohio
| | - Tsuyoshi Hayashi
- National Institute of Biomedical Innovation, Health and Nutrition, Osaka, Japan
| | - Jian Zhu
- Department of Pathology, The Ohio State University Wexner Medical Center, Columbus, Ohio
| |
Collapse
|
5
|
Ingilizova M, Epstein S, Heun Lee D, Patel N, Patel Babariya S, Morgenstern R, Popnikolov N, Coppock D. A rare case of disseminated Mycobacterium avium complex with colitis in a renal transplant recipient. Transpl Infect Dis 2018; 21:e13011. [PMID: 30298542 DOI: 10.1111/tid.13011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 09/18/2018] [Accepted: 10/01/2018] [Indexed: 01/15/2023]
Abstract
Mycobacterium avium complex (MAC) colitis is a rare complication of immunosuppression in solid organ transplant (SOT) recipients. Here, we describe a case of disseminated MAC infection with colitis following renal transplantation. Despite common pathways of immunosuppression, SOT recipients and human immunodeficiency virus (HIV)-infected patients differ in their typical presentations of MAC infection. Intestinal infections have been more commonly reported in HIV-infected patients than in SOT recipients. The explanation for this difference may be related to HIV's targeted effects on the CD4+ T-cell reservoir in gut-associated lymphoid tissue.
Collapse
Affiliation(s)
- Marinela Ingilizova
- Division of Infectious Diseases and HIV Medicine, Department of Medicine, Drexel University College of Medicine, Philadelphia, Pennsylvania
| | - Shara Epstein
- Division of Infectious Diseases and HIV Medicine, Department of Medicine, Drexel University College of Medicine, Philadelphia, Pennsylvania
| | - Dong Heun Lee
- Division of Infectious Diseases and HIV Medicine, Department of Medicine, Drexel University College of Medicine, Philadelphia, Pennsylvania
| | - Neal Patel
- Division of Gastroenterology and Hepatology, Department of Medicine, Drexel University College of Medicine, Philadelphia, Pennsylvania
| | - Shraddha Patel Babariya
- Department of Pathology and Laboratory Medicine, Drexel University College of Medicine, Philadelphia, Pennsylvania
| | - Ricardo Morgenstern
- Division of Gastroenterology and Hepatology, Department of Medicine, Drexel University College of Medicine, Philadelphia, Pennsylvania
| | - Nikolay Popnikolov
- Department of Pathology and Laboratory Medicine, Drexel University College of Medicine, Philadelphia, Pennsylvania
| | - Dagan Coppock
- Division of Infectious Diseases and HIV Medicine, Department of Medicine, Drexel University College of Medicine, Philadelphia, Pennsylvania
| |
Collapse
|
6
|
Stein J, Storcksdieck Genannt Bonsmann M, Streeck H. Barriers to HIV Cure. HLA 2018; 88:155-63. [PMID: 27620852 DOI: 10.1111/tan.12867] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Accepted: 08/08/2016] [Indexed: 02/06/2023]
Abstract
Since the beginning of the epidemic, more than 70 million people have been infected with human immunodeficiency virus (HIV) and about 38 million have died from acquired immune deficiency syndrome (AIDS)-related illnesses. While the discovery of highly active antiretroviral therapy (HAART) in the mid 90's has saved millions of lives, a complete eradication of HIV is still not possible as HIV can persist for decades in a small reservoir of latently infected cells. Once reactivated, these latently infected cells can actively produce viral particles. Recent studies suggest that several sanctuaries exist within infected individuals where HIV can remain undetected by the immune system. These cellular, anatomical and microanatomical viral reservoirs represent a major obstacle for the eradication of HIV. Here we review recent findings on potential sanctuaries of HIV and address potential avenues to overcome these immunological barriers.
Collapse
Affiliation(s)
- J Stein
- Institute for HIV Research, University Hospital Essen, University Duisburg-Essen, Essen, Germany.
| | | | - H Streeck
- Institute for HIV Research, University Hospital Essen, University Duisburg-Essen, Essen, Germany.,US Military HIV Research Program, Henry M. Jackson Foundation, Rockville, MD, USA
| |
Collapse
|
7
|
Zaunders J, Xu Y, Kent SJ, Koelsch KK, Kelleher AD. Divergent Expression of CXCR5 and CCR5 on CD4 + T Cells and the Paradoxical Accumulation of T Follicular Helper Cells during HIV Infection. Front Immunol 2017; 8:495. [PMID: 28553284 PMCID: PMC5427074 DOI: 10.3389/fimmu.2017.00495] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2016] [Accepted: 04/10/2017] [Indexed: 12/23/2022] Open
Abstract
Viral infection sets in motion a cascade of immune responses, including both CXCR5+CD4+ T follicular helper (Tfh) cells that regulate humoral immunity and CCR5+CD4+ T cells that mediate cell-mediated immunity. In peripheral blood mononuclear cells, the majority of memory CD4+ T cells appear to fall into either of these two lineages, CCR5−CXCR5+ or CCR5+CXCR5−. Very high titers of anti-HIV IgG antibodies are a hallmark of infection, strongly suggesting that there is significant HIV-specific CD4+ T cell help to HIV-specific B cells. We now know that characteristic increases in germinal centers (GC) in lymphoid tissue (LT) during SIV and HIV-1 infections are associated with an increase in CXCR5+PD-1high Tfh, which expand to a large proportion of memory CD4+ T cells in LT, and are presumably specific for SIV or HIV epitopes. Macaque Tfh normally express very little CCR5, yet are infected by CCR5-using SIV, which may occur mainly through infection of a subset of PD-1intermediateCCR5+Bcl-6+ pre-Tfh cells. In contrast, in human LT, a subset of PD-1high Tfh appears to express low levels of CCR5, as measured by flow cytometry, and this may also contribute to the high rate of infection of Tfh. Also, we have found, by assessing fine-needle biopsies of LT, that increases in Tfh and GC B cells in HIV infection are not completely normalized by antiretroviral therapy (ART), suggesting a possible long-lasting reservoir of infected Tfh. In contrast to the increase of CXCR5+ Tfh, there is no accumulation of proliferating CCR5+ CD4 T HIV Gag-specific cells in peripheral blood that make IFN-γ. Altogether, CXCR5+CCR5− CD4 T cells that regulate humoral immunity are allowed greater freedom to operate and expand during HIV-1 infection, but at the same time can contain HIV DNA at levels at least as high as in other CD4 subsets. We argue that early ART including a CCR5 blocker may directly reduce the infected Tfh reservoir in LT and also interrupt cycles of antibody pressure driving virus mutation and additional GC responses to resulting neoantigens.
Collapse
Affiliation(s)
- John Zaunders
- St Vincent's Centre for Applied Medical Research, St Vincent's Hospital, Sydney, NSW, Australia.,The Kirby Institute, The University of New South Wales, Sydney, NSW, Australia
| | - Yin Xu
- The Kirby Institute, The University of New South Wales, Sydney, NSW, Australia
| | - Stephen J Kent
- Department of Microbiology and Immunology, Peter Doherty Institute, University of Melbourne, Melbourne, VIC, Australia.,Department of Infectious Diseases, Alfred Hospital, Monash University, Melbourne, VIC, Australia
| | - Kersten K Koelsch
- The Kirby Institute, The University of New South Wales, Sydney, NSW, Australia
| | - Anthony D Kelleher
- St Vincent's Centre for Applied Medical Research, St Vincent's Hospital, Sydney, NSW, Australia.,The Kirby Institute, The University of New South Wales, Sydney, NSW, Australia
| |
Collapse
|
8
|
Ripa M, Chiappetta S, Tambussi G. Immunosenescence and hurdles in the clinical management of older HIV-patients. Virulence 2017; 8:508-528. [PMID: 28276994 DOI: 10.1080/21505594.2017.1292197] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
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.
Collapse
Affiliation(s)
- Marco Ripa
- a Department of Infectious and Tropical Diseases , Ospedale San Raffaele , Milan , Italy
| | - Stefania Chiappetta
- a Department of Infectious and Tropical Diseases , Ospedale San Raffaele , Milan , Italy
| | - Giuseppe Tambussi
- a Department of Infectious and Tropical Diseases , Ospedale San Raffaele , Milan , Italy
| |
Collapse
|
9
|
Fink DL, Hedley L, Miller RF. Systematic review of the efficacy and safety of biological therapy for inflammatory conditions in HIV-infected individuals. Int J STD AIDS 2016; 28:110-119. [PMID: 27733707 DOI: 10.1177/0956462416675109] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Biologic therapies are injectable immunomodulatory agents directed against specific immune cell or chemical targets. They have transformed the lives of HIV-uninfected individuals with severe inflammatory conditions including psoriasis, rheumatoid arthritis, and ulcerative colitis. The perceived increased infection risk associated with these agents means that HIV-infected individuals have not been included in randomised control trials of these drugs. The literature for use of biologic therapies in HIV-infected populations is limited to case reports and case series. There are additional data on use of rituximab, a monoclonal antibody against B lymphocytes, in the setting of HIV-associated haematological malignancy. We performed a systematic review of efficacy and safety of biologic therapy for inflammatory conditions in HIV-infected individuals. Our systematic review identified 37 treatment episodes with six different biologic agents encompassing 10 different inflammatory conditions. Broadly, efficacy of the agents studied was comparable to reports from HIV-uninfected patients. Both infectious and non-infectious sequelae were also comparable with trial data from HIV-uninfected patients. HIV control, even for the minority of individuals not receiving anti-retroviral therapy (ART) at the time of biologic therapy, was not adversely affected. However, detail was limited concerning ART regimens and both immunological and virological parameters of follow-up. Overall available literature is of very low quality and likely subject to publication bias of successful cases. Firm conclusions are not possible regarding the efficacy and safety of biologic agents in HIV-infected individuals; however, there appear to be sufficient data to warrant inclusion of individuals with well-controlled HIV in future trial studies.
Collapse
Affiliation(s)
- D L Fink
- 1 Department of Infectious and Tropical Diseases, Hospital for Tropical Diseases, University College London Hospitals NHS Foundation Trust, UK
| | - L Hedley
- 2 Pharmacy Department, University College London Hospitals NHS Foundation Trust, UK
| | - R F Miller
- 3 Research Department of Infection and Population Health, University College London, London, UK.,4 Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| |
Collapse
|
10
|
Zhang C, Zhou S, Groppelli E, Pellegrino P, Williams I, Borrow P, Chain BM, Jolly C. Hybrid spreading mechanisms and T cell activation shape the dynamics of HIV-1 infection. PLoS Comput Biol 2015; 11:e1004179. [PMID: 25837979 PMCID: PMC4383537 DOI: 10.1371/journal.pcbi.1004179] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 02/04/2015] [Indexed: 02/07/2023] Open
Abstract
HIV-1 can disseminate between susceptible cells by two mechanisms: cell-free infection following fluid-phase diffusion of virions and by highly-efficient direct cell-to-cell transmission at immune cell contacts. The contribution of this hybrid spreading mechanism, which is also a characteristic of some important computer worm outbreaks, to HIV-1 progression in vivo remains unknown. Here we present a new mathematical model that explicitly incorporates the ability of HIV-1 to use hybrid spreading mechanisms and evaluate the consequences for HIV-1 pathogenenesis. The model captures the major phases of the HIV-1 infection course of a cohort of treatment naive patients and also accurately predicts the results of the Short Pulse Anti-Retroviral Therapy at Seroconversion (SPARTAC) trial. Using this model we find that hybrid spreading is critical to seed and establish infection, and that cell-to-cell spread and increased CD4+ T cell activation are important for HIV-1 progression. Notably, the model predicts that cell-to-cell spread becomes increasingly effective as infection progresses and thus may present a considerable treatment barrier. Deriving predictions of various treatments' influence on HIV-1 progression highlights the importance of earlier intervention and suggests that treatments effectively targeting cell-to-cell HIV-1 spread can delay progression to AIDS. This study suggests that hybrid spreading is a fundamental feature of HIV infection, and provides the mathematical framework incorporating this feature with which to evaluate future therapeutic strategies.
Collapse
Affiliation(s)
- Changwang Zhang
- Department of Computer Science, University College London, London, United Kingdom
- Security Science Doctoral Research Training Centre, University College London, London, United Kingdom
- School of Computer Science, National University of Defense Technology, Changsha, China
| | - Shi Zhou
- Department of Computer Science, University College London, London, United Kingdom
| | - Elisabetta Groppelli
- Division of Infection and Immunity, University College London, London, United Kingdom
| | - Pierre Pellegrino
- Centre for Sexual Health & HIV Research, Mortimer Market Centre, London, United Kingdom
| | - Ian Williams
- Centre for Sexual Health & HIV Research, Mortimer Market Centre, London, United Kingdom
| | - Persephone Borrow
- Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Benjamin M. Chain
- Division of Infection and Immunity, University College London, London, United Kingdom
| | - Clare Jolly
- Division of Infection and Immunity, University College London, London, United Kingdom
| |
Collapse
|
11
|
Tedbury PR, Freed EO. HIV-1 gag: an emerging target for antiretroviral therapy. Curr Top Microbiol Immunol 2015; 389:171-201. [PMID: 25731773 DOI: 10.1007/82_2015_436] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
Abstract
The advances made in the treatment of HIV-1 infection represent a major success of modern biomedical research, prolonging healthy life and reducing virus transmission. There remain, however, many challenges relating primarily to side effects of long-term therapy and the ever-present danger of the emergence of drug-resistant strains. To counter these threats, there is a continuing need for new and better drugs, ideally targeting multiple independent steps in the HIV-1 replication cycle. The most successful current drugs target the viral enzymes: protease (PR), reverse transcriptase (RT), and integrase (IN). In this review, we outline the advances made in targeting the Gag protein and its mature products, particularly capsid and nucleocapsid, and highlight possible targets for future pharmacological intervention.
Collapse
Affiliation(s)
- Philip R Tedbury
- Virus-Cell Interaction Section, HIV Drug Resistance Program, National Cancer Institute, Center for Cancer Research, Frederick, MD, 21702-1201, USA
| | | |
Collapse
|
12
|
Ipp H, Zemlin AE, Erasmus RT, Glashoff RH. Role of inflammation in HIV-1 disease progression and prognosis. Crit Rev Clin Lab Sci 2014; 51:98-111. [PMID: 24479745 DOI: 10.3109/10408363.2013.865702] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Inflammation and immune activation have been thrust to center stage in the understanding of HIV-1 disease pathogenesis and progression. Early work demonstrated that heightened levels of immune activation correlated with the extent of CD4 + T cell death in lymphoid tissue; however, this concept was not incorporated into the general view of disease pathogenesis. Since these early studies, the extension of life for patients on combination antiretroviral therapies (cART) has heralded a new era of non-AIDS-related diseases and incomplete restoration of immune function. The common link appears to be ongoing inflammation and immune activation. Thus, despite good control of viral loads, persons living with HIV (PLWH) remain at increased risk of inflammatory-associated complications such as cardiovascular disease and certain cancers. HIV-specific mechanisms as well as non-specific generalized responses to infection contribute to ongoing activation of the immune system. An early loss of gastrointestinal (GI) tract mucosal integrity, the pro-inflammatory cytokine milieu, co-infections and marked destruction of lymph node architecture are all factors contributing to the ongoing activation of the immune system as well as impaired immune recovery. It is becoming increasingly evident that the CD4 count and viral load do not provide a complete picture of the underlying state of the immune system. Heightened levels of inflammatory markers have been shown to predict increased mortality and other adverse events. Therefore, it will be important to incorporate these markers into management algorithms as soon as possible. This is particularly relevant in resource-poor countries where difficulties in cART roll-out and access are still encountered and, therefore, a mechanism for prioritizing individuals for therapy would be of value. This review will focus on the closely inter-related concepts of immune activation and inflammation. Both are broad concepts involving the interaction of various key players in the immune system. Importantly, immune activation promotes inflammation and thrombosis and similarly, inflammation and thrombosis induce immune activation. These concepts are thus intricately linked. Studies highlighting the potentially harmful effects of ongoing inflammation/immune activation are reviewed and the contributions of the GI tract "damage" and other co-infections such as CMV are explored. The complications resulting from persistent immune activation include enhanced CD4 + T cell death, lymphoid tissue destruction, and various pathologies related to chronic inflammation. Ultimately, we envision that the long-term management of the disease will incorporate both the identification and the amelioration of the potentially harmful effects of ongoing immune activation and inflammation.
Collapse
|
13
|
Abstract
Systemic chronic immune activation is considered today as the driving force of CD4(+) T-cell depletion and acquired immunodeficiency syndrome (AIDS). A residual chronic immune activation persists even in HIV-infected patients in which viral replication is successfully inhibited by anti-retroviral therapy, with the extent of this residual immune activation being associated with CD4(+) T-cell loss. Unfortunately, the causal link between chronic immune activation and CD4(+) T-cell loss has not been formally established. This article provides first a brief historical overview on how the perception of the causative role of immune activation has changed over the years and lists the different kinds of immune activation characteristic of human immunodeficiency virus (HIV) infection. The mechanisms proposed to explain the chronic immune activation are multiple and are enumerated here, as well as the mechanisms proposed on how chronic immune activation could lead to AIDS. In addition, we summarize the lessons learned from natural hosts that know how to 'show AIDS the door', and discuss how these studies informed the design of novel immune modulatory interventions that are currently being tested. Finally, we review the current approaches aimed at targeting chronic immune activation and evoke future perspectives.
Collapse
Affiliation(s)
- Mirko Paiardini
- Division of Microbiology and Immunology, Yerkes National Primate Research Center, and Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA 30329, USA.
| | | |
Collapse
|
14
|
Ipp H, Zemlin A. The paradox of the immune response in HIV infection: when inflammation becomes harmful. Clin Chim Acta 2012; 416:96-9. [PMID: 23228847 DOI: 10.1016/j.cca.2012.11.025] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Revised: 11/20/2012] [Accepted: 11/23/2012] [Indexed: 01/11/2023]
Abstract
HIV-infection is associated with ongoing activation of the immune system and persistent inflammation. These are key driving forces in the loss of CD4+ T cells, progression to AIDS and development of non-HIV-related complications such as cardiovascular disease and certain cancers. Diseases associated with accelerated aging are increasing in incidence despite good anti-retroviral therapy (ART). The common underlying mechanism appears to be chronic inflammation. HIV-specific mechanisms as well as non-specific generalized responses to infection contribute to the chronic and aberrant activation of the immune system. An early loss of gut mucosal integrity, the pro-inflammatory cytokine milieu, co-infections and later, marked destruction of lymph node architecture are all factors contributing to the ongoing activation of both the innate and adaptive immune systems. These factors paradoxically promote CD4+ T cell loss, both by providing additional substrate for viral infection in the form of activated CD4+ T cells, as well as by priming non-infected 'bystander' CD4+ T cells for death by apoptosis. However, the relative contributions of each of these mechanisms to ongoing immune activation remain to be determined. Cost-effective markers of inflammation and selective anti-inflammatory agents are important fields of current and future research.
Collapse
Affiliation(s)
- Hayley Ipp
- Division of Haematology, Department of Pathology, Stellenbosch University and National Health Laboratory Service (NHLS), Tygerberg Hospital, Cape Town, South Africa.
| | | |
Collapse
|
15
|
Ganesan A, Crum-Cianflone N, Higgins J, Qin J, Rehm C, Metcalf J, Brandt C, Vita J, Decker CF, Sklar P, Bavaro M, Tasker S, Follmann D, Maldarelli F. High dose atorvastatin decreases cellular markers of immune activation without affecting HIV-1 RNA levels: results of a double-blind randomized placebo controlled clinical trial. J Infect Dis 2011; 203:756-64. [PMID: 21325137 DOI: 10.1093/infdis/jiq115] [Citation(s) in RCA: 110] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase inhibitors (statins) exhibit antiviral activity against human immunodeficiency virus type 1 (HIV-1) in vitro and may modulate the immune response to HIV infection. Studies evaluating the antiviral activity of statins have yielded conflicting results. METHODS We conducted a randomized, double-blind, placebo-controlled crossover trial to investigate the effect of atorvastatin on HIV-1 RNA (primary objective) and cellular markers of immune activation (secondary objective). HIV-infected individuals not receiving antiretroviral therapy were randomized to receive either 8 weeks of atorvastatin (80 mg) or placebo daily. After a 4-6 week washout phase, participants switched treatment assignments. The study had 80% power to detect a 0.3 log(10) decrease in HIV-1 RNA level. Expression of CD38 and HLA-DR on CD4(+) and CD8(+) T cells was used to measure immune activation. RESULTS Of 24 randomized participants, 22 completed the study. Although HIV-1 RNA level was unaffected by the intervention (-0.13 log(10) copies/mL; P = .85), atorvastatin use resulted in reductions in circulating proportions of CD4(+) HLA-DR(+) (-2.5%; P = .02), CD8(+) HLA-DR(+) (-5%; P = .006), and CD8(+) HLA-DR(+) CD38(+) T cells (-3%; P = .03). Reductions in immune activation did not correlate with declines in serum levels of low-density lipoprotein cholesterol. CONCLUSIONS Short-term use of atorvastatin was associated with modest but statistically significant reductions in the proportion of activated T lymphocytes.
Collapse
Affiliation(s)
- Anuradha Ganesan
- Division of Infectious Diseases, National Naval Medical Center, Uniformed Services University, Bethesda, Maryland, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Borchi B, Ambu S, Bresci S, Zanazzi M, Salvadori M, Leoncini F. Case report: HIV infection from a kidney transplant. Transplant Proc 2011; 42:2267-9. [PMID: 20692460 DOI: 10.1016/j.transproceed.2010.05.026] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The transmission of human immunodeficiency virus (HIV) through transplantation of human tissues and organs is rare but not impossible. A 27-year-old Bulgarian woman received a kidney transplant from a cadaveric donor owing to chronic renal failure due to glomerulonephritis of unknown etiology. Five days after the donation, the tissues showed HIV-1 infection, so she was immediately initiated on highly active antiretroviral therapy (HAART) with lopinavir/ritonavir, zidovudine, enfuvirtide, and lamivudine. Subsequently, according to the genotypic test which revealed a complex resistance pattern of the HIV-1, we changed the regimen to darunavir/ritonavir, etravirine, lamivudine, and enfuvirtide. The HIV-1 genome (550 UI/mL), which was detected at 5 days after transplantation, rapidly declined to undetectable levels at 3 weeks after HAART. The CD4+ T-cell nadir was 432 cells/microL (40%) to 1,400 cells/microL after 2 years. The posttransplantation course was complicated by cytomegalovirus pneumonia. At 32 months after transplantation, the patient had experienced hypertension with secondary retinopathy, bilateral cataracts, diabetes, hypothyroidism, osteoporosis with multiple vertebral fractures, a hip prosthesis, and a bone infarction of the femur. Major management problems had been related to steroid and HAART treatment side effects. Therapeutic interactions between the immunosuppressants and the antiretroviral drugs were complex for management, requiring frequent checks of drug levels and dose-adjustments. We finally obtained a stable clinical and viroimmunologic condition. The transmission of multiresistant strains of HIV from unknown patients requires complex multidisciplinary management.
Collapse
Affiliation(s)
- B Borchi
- Infectious Disease Department, Careggi University and Hospital, Firenze, Italy.
| | | | | | | | | | | |
Collapse
|
17
|
Read SW, DeGrezia M, Ciccone EJ, DerSimonian R, Higgins J, Adelsberger JW, Starling JM, Rehm C, Sereti I. The effect of leflunomide on cycling and activation of T-cells in HIV-1-infected participants. PLoS One 2010; 5:e11937. [PMID: 20689824 PMCID: PMC2914784 DOI: 10.1371/journal.pone.0011937] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2010] [Accepted: 06/15/2010] [Indexed: 11/21/2022] Open
Abstract
Background The pathogenesis of immunodeficiency due to human immunodeficiency virus (HIV)-1 is incompletely understood, but immune activation is believed to play a central role. Immunomodulatory agents that decrease immune activation may be useful in the treatment of HIV-1 infection. Methodology A randomized, double blind, placebo-controlled pilot study of leflunomide for 28 days was performed in participants with HIV-1 infection who were not receiving antiretroviral therapy. Participants randomized to leflunomide were subsequently treated with cholestyramine until leflunomide levels were below detection limit. Findings Treatment with leflunomide was well tolerated with mostly low-grade adverse events. Leflunomide administration reduced cycling of CD4 T cells (by ex vivo bromodeoxyuridine uptake and Ki67 expression) and decreased expression of activation markers (HLA-DR/CD38 co-expression) on CD8 T cells in peripheral blood. In addition, decreased expression of HIV-1 co-receptors was observed in both CD4 and CD8 T cells in the leflunomide group. There were no significant changes in naïve and memory T cell subsets, apoptosis of T cells or markers of microbial translocation. Conclusions Leflunomide was effective in reducing immune activation in the setting of chronic HIV-1 infection suggesting that targeting immune activation with immunomodulatory agents may be a feasible strategy. Trial Registration ClinicalTrials.gov NCT00101374
Collapse
Affiliation(s)
- Sarah W. Read
- Division of AIDS, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Mary DeGrezia
- Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Emily J. Ciccone
- Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Rebecca DerSimonian
- Biostatistics Research Branch, Division of Clinical Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Jeanette Higgins
- Science Applications International Corporation-Frederick, National Cancer Institute-Frederick, Frederick, Maryland, United States of America
| | - Joseph W. Adelsberger
- Science Applications International Corporation-Frederick, National Cancer Institute-Frederick, Frederick, Maryland, United States of America
| | - Judith M. Starling
- Department of Pharmacy, National Institutes of Health Clinical Center, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Catherine Rehm
- Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Irini Sereti
- Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail:
| |
Collapse
|
18
|
Abstract
PURPOSE OF REVIEW Recent work in pathogenic simian immunodeficiency (SIV) infection of Asian macaques and in natural, nonpathogenic SIV infections of African nonhuman primate species has demonstrated that persistent activation has profound effects on CD4+ memory T-cell proliferation, differentiation and survival. Disease progression in pathogenic infection has been closely linked to these dynamics, reflecting a complex interplay of virus-mediated killing, the effects of systemic activation and host regenerative mechanisms. We review these recent advances. RECENT FINDINGS Massive depletion of CD4+ effector-memory T cells invariably occurs during acute CCR5-tropic SIV infection, but is initially stabilized by new production of these cells from spared central memory precursors above the threshold required to maintain clinical immune competence. In pathogenic (but not natural, apathogenic) infections, a persistent state of immune activation, characterized by multiple, recurrent bursts of lymphocyte proliferation, differentiation, migration, death and functional modification of 'resting' cells, is associated with progressive depletion of central memory CD4+ T cells, and ultimately, a collapse of effector site CD4+ memory populations that is closely associated with overt immune deficiency. SUMMARY The importance of maintaining the regenerative capacity of the central-memory compartment of CD4+ T cells is increasingly evident. Defining the physiologic and molecular mechanisms responsible for instability of the CD4+ central-memory T cell pool could enable new immunotherapeutic interventions.
Collapse
|
19
|
Hulgan T, Donahue JP, Smeaton L, Pu M, Wang H, Lederman MM, Smith K, Valdez H, Pilcher C, Haas DW. Oral cyclosporin A inhibits CD4 T cell P-glycoprotein activity in HIV-infected adults initiating treatment with nucleoside reverse transcriptase inhibitors. Eur J Clin Pharmacol 2009; 65:1081-8. [PMID: 19779705 DOI: 10.1007/s00228-009-0725-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2009] [Accepted: 08/31/2009] [Indexed: 12/12/2022]
Abstract
PURPOSE P-glycoprotein limits the tissue penetration of many antiretroviral drugs. The aim of our study was to characterize the effects of the P-glycoprotein substrate cyclosporin A on T cell P-glycoprotein activity in human immunodeficiency virus-infected participants in the AIDS Clinical Trials Group study A5138. METHODS We studied P-glycoprotein activity on CD4 and CD8 T cells in 16 participants randomized to receive oral cyclosporin A (n=9) or not (n=7) during initiation antiretroviral therapy (ART) that did not include protease or non-nucleoside reverse transcriptase inhibitors. RESULTS CD4 T cell P-glycoprotein activity decreased by a median of 8 percentage points with cyclosporin A/ART (difference between cyclosporin A/ART vs. ART only, P= 0.001). Plasma trough cyclosporin A concentrations correlated with the change in P-glycoprotein activity in several T cell subsets. CONCLUSIONS Oral cyclosporin A can inhibit peripheral blood CD4 T cell P-glycoprotein activity. Targeted P-glycoprotein inhibition may enhance the delivery of ART to T cells.
Collapse
Affiliation(s)
- Todd Hulgan
- Department of Medicine, Division of Infectious Diseases, Vanderbilt University School of Medicine, Nashville, TN 37203, USA.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Hofer U, Speck RF. Disturbance of the gut-associated lymphoid tissue is associated with disease progression in chronic HIV infection. Semin Immunopathol 2009; 31:257-66. [PMID: 19484240 DOI: 10.1007/s00281-009-0158-3] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2009] [Accepted: 05/14/2009] [Indexed: 02/06/2023]
Abstract
Why and how HIV makes people sick is highly debated. Recent evidence implicates heightened immune activation due to breakdown of the gastrointestinal barrier as a determining factor of lentiviral pathogenesis. HIV-mediated loss of Th17 cells from the gut-associated lymphoid tissue (GALT) impairs mucosal integrity and innate defense mechanisms against gut microbes. Translocation of microbial products from the gut, in turn, correlates with increased immune activation in chronic HIV infection and may further damage the immune system by increasing viral and activation-induced T cell death, by reducing T cell reconstitution due to tissue scarring, and by impairing the function of other cell types, such as gammadelta T cells and epithelial cells. Maintaining a healthy GALT may be the key to reducing the pathogenic potential of HIV.
Collapse
Affiliation(s)
- Ursula Hofer
- Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland.
| | | |
Collapse
|
21
|
Gazzola L, Tincati C, Bellistre GM, d'Arminio Monforte A, Marchetti G. The Absence of CD4+ T Cell Count Recovery Despite Receipt of Virologically Suppressive Highly Active Antiretroviral Therapy: Clinical Risk, Immunological Gaps, and Therapeutic Options. Clin Infect Dis 2009. [DOI: 10.1086/695852] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
|
22
|
Gazzola L, Tincati C, Bellistrì GM, Monforte AD, Marchetti G. The absence of CD4+ T cell count recovery despite receipt of virologically suppressive highly active antiretroviral therapy: clinical risk, immunological gaps, and therapeutic options. Clin Infect Dis 2009; 48:328-37. [PMID: 19123868 DOI: 10.1086/595851] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Up to 30% of human immunodeficiency virus (HIV)-infected patients who are receiving long-term highly active antiretroviral therapy do not exhibit a marked increase in the CD4(+) T cell count, despite achieving complete suppression of the HIV load. These patients are referred to as "immunological nonresponders." When treating immunological nonresponders, the practicing clinician has several questions, including questions about the clinical risk associated with persistent immunodeficiency and about possible approaches to treatment that would provide clinical and immunological benefits. However, tentative answers to these questions require investigations of the mechanisms that underlie the lack of immune recovery, because only the deepest comprehension of the immunological gaps underlying functional defects will allow administration of highly targeted and efficacious treatment strategies. The aim of our review is to provide a thorough assessment of the clinical implications of a lack of increase in the CD4(+) T cell count in immunological nonresponders, to examine the immunological gaps limiting recovery of the CD4(+) T cell count, and to note possible therapeutic avenues, which may offer clinicians guidance regarding how to most efficaciously treat these critical patients.
Collapse
Affiliation(s)
- Lidia Gazzola
- Department of Medicine, Surgery, and Dentistry, Clinic of Infectious Diseases, San Paolo Hospital, University of Milan, Milan, Italy
| | | | | | | | | |
Collapse
|
23
|
Silvestri G, Paiardini M, Pandrea I, Lederman MM, Sodora DL. Understanding the benign nature of SIV infection in natural hosts. J Clin Invest 2008; 117:3148-54. [PMID: 17975656 DOI: 10.1172/jci33034] [Citation(s) in RCA: 166] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
In striking contrast to HIV infection, natural SIV infection of African nonhuman primates is asymptomatic and usually does not induce significant CD4+ T cell depletion despite high levels of virus replication. Recently, significant progress has been made in understanding the mechanisms underlying the remarkable difference in infection outcome between natural and nonnatural HIV/SIV hosts. These advances include the identification of limited immune activation as a key factor protecting natural SIV hosts from AIDS and the discovery of low CC chemokine receptor 5 expression on CD4+ T cells as a specific and consistent immunologic feature in these animals. Further elucidation of the pathways by which the differences in immune activation between natural and nonnatural hosts are manifest holds promise for the design of novel therapeutic approaches to HIV infection.
Collapse
Affiliation(s)
- Guido Silvestri
- Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA.
| | | | | | | | | |
Collapse
|
24
|
Appay V, Sauce D. Immune activation and inflammation in HIV-1 infection: causes and consequences. J Pathol 2008; 214:231-41. [PMID: 18161758 DOI: 10.1002/path.2276] [Citation(s) in RCA: 525] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Thorough research on HIV is progressively enabling us to understand the intricate mechanisms that link HIV-1 infection to the onset of immunodeficiency. The infection and depletion of CD4(+) T cells represent the most fundamental events in HIV-1 infection. However, in recent years, the role played by chronic immune activation and inflammation in HIV pathogenesis has become increasingly apparent: quite paradoxically, immune activation levels are directly associated with HIV-1 disease progression. In addition, HIV-1-infected patients present intriguing similarities with individuals of old age: their immune systems are characterized by a loss of regenerative capacity and an accumulation of ageing T cells. In this review, we discuss the potential reasons for the establishment of sustained immune activation and inflammation from the early stages of HIV-1 infection, as well as the long-term consequences of this process on the host immune system and health. A simplified model of HIV pathogenesis is proposed, which links together the three major facets of HIV-1 infection: the massive depletion of CD4(+) T cells, the paradoxical immune activation and the exhaustion of regenerative capacity.
Collapse
Affiliation(s)
- V Appay
- Cellular Immunology Laboratory, INSERM U543, Hopital Pitie-Salpetriere, Université Pierre et Marie Curie-Paris6, Paris, France.
| | | |
Collapse
|
25
|
|
26
|
|
27
|
De Maria A. Discordant responses to HAART in HIV-1 patients: the need to focus on intervention. Expert Rev Anti Infect Ther 2007; 5:523-7. [PMID: 17678414 DOI: 10.1586/14787210.5.4.523] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
|
28
|
Wainberg MA, Clotet B. Review: immunologic response to protease inhibitor-based highly active antiretroviral therapy: a review. AIDS Patient Care STDS 2007; 21:609-20. [PMID: 17919088 DOI: 10.1089/apc.2006.0176] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
A substantial body of evidence indicates that CD4 cell count is an important independent prognostic indicator for progression of HIV disease. Consequently, in addition to plasma HIV RNA levels, CD4 cell count change is considered to be a key surrogate marker for disease progression in clinical practice and in clinical studies. Given the relationship between changes in CD4 count and disease progression, it is notable that protease inhibitor (PI)-based highly active antiretroviral therapy (HAART) can rapidly increase CD4 cell count early in treatment in both therapy-naïve and -experienced patients, and can sustain clinically relevant levels beyond 24 weeks. A number of trials with a follow-up of more than 3 years allow us to conclude that the gains in CD4 counts are maintained in a durable manner. This review evaluated randomized studies of PI-based and PI-boosted HAART (published between January 1996 and February 2006) to determine the effect of PI-based therapy on CD4 cell count. Only studies that assessed CD4 response in the overall patient population were included. Four mechanisms have been proposed to account for the rapid increase in CD4 cell count that occurs with HAART: CD4 cell redistribution from lymphatic tissues, increased CD4 cell production, reduction of apoptotic CD4 cells and the recovery of hematopoietic activity in bone marrow. Further research is required to clarify the relative importance of these mechanisms and ways in which they might be enhanced.
Collapse
Affiliation(s)
- Mark A. Wainberg
- McGill University AIDS Center, Jewish General Hospital, Montreal, Quebec, Canada
| | - Bonaventura Clotet
- HIV Clinical Unit and Irsicaixa Foundation, Hospital Universitari Germans Trias i Pujol, Barcelona, Spain
| |
Collapse
|
29
|
|
30
|
Abstract
T-cell activation has long been considered a central mediator of HIV pathogenesis. High T-cell activation levels predict more rapid disease progression in untreated patients and decreased treatment-mediated CD4+ T-cell gains during antiretroviral therapy, independent of plasma HIV RNA levels, and may be the primary feature distinguishing pathogenic from nonpathogenic primate models of HIV infection. Studies in animal models and individuals with HIV infection continue to enhance our understanding of how T-cell activation causes immunodeficiency during HIV infection. The goal of these studies is to identify specific mechanisms that can be targeted by novel immune-based therapies for patients who have thus far been unable to recover normal immune function despite years of antiretroviral therapy. Although most immune-based therapies targeting T-cell activation have been unsuccessful to date, recent scientific developments have focused attention on specific pathways that may be exploited by future generations of immune-based therapies.
Collapse
Affiliation(s)
- Peter W Hunt
- Positive Health Program, San Francisco General Hospital, Building 80, Ward 84, 995 Potrero Avenue, San Francisco, CA 94110, USA.
| |
Collapse
|