scholarly journals SIV infection aggravates malaria in a Chinese rhesus monkey coinfection model

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Guangjie Liu ◽  
Youjia Li ◽  
Li Qin ◽  
Yongxiang Yan ◽  
Yijian Ye ◽  
...  

Abstract Background The co-occurrence of human immunodeficiency virus (HIV) infection and malaria in humans in endemic areas raises the question of whether one of these infections affects the course of the other. Although epidemiological studies have shown the impact of HIV infection on malaria, the mechanism(s) are not yet fully understood. Using a Chinese rhesus macaque coinfection model with simian immunodeficiency virus (SIV) and Plasmodium cynomolgi (Pc) malaria, we investigated the effect of concurrent SIV infection on the course of malaria and the underlying immunological mechanism(s). Methods We randomly assigned ten Chinese rhesus monkeys to two groups based on body weight and age. The SIV-Pc coinfection animals (S + P group) were infected intravenously with SIVmac251 eight weeks prior to malaria infection, and the control animals (P group) were infected intravenously with only Pc-infected red blood cells. After malaria was cured with chloroquine phosphate, we also initiated a secondary malaria infection that lasted 4 weeks. We monitored body weight, body temperature and parasitemia, measured SIV viral loads, hemoglobin and neopterin, and tracked the CD4+, CD8+, and CD4+ memory subpopulations, Ki67 and apoptosis by flow cytometry. Then, we compared these parameters between the two groups. Results The animals infected with SIV prior to Pc infection exhibited more severe malaria symptoms characterized by longer episodes, higher parasitemia, more severe anemia, greater body weight loss and higher body temperature than the animals infected with Pc alone. Concurrent SIV infection also impaired immune protection against the secondary Pc challenge infection. The coinfected animals showed a reduced B cell response to Pc malaria and produced lower levels of Pc-specific antibodies. In addition, compared to the animals subjected to Pc infection alone, the animals coinfected with SIV and Pc had suppressed total CD4+ T cells, CD4+CD28highCD95high central memory T cells, and CD4+CD28lowCD95− naïve T cells, which may result from the imbalanced immune activation and faster CD4+ T cell turnover in coinfected animals. Conclusions SIV infection aggravates malaria physiologically and immunologically in Chinese rhesus monkeys. This nonhuman primate SIV and Pc malaria coinfection model might be a useful tool for investigating human HIV and malaria coinfection and developing effective therapeutics.

2008 ◽  
Vol 82 (11) ◽  
pp. 5631-5635 ◽  
Author(s):  
Eun-Young Kim ◽  
Ronald S. Veazey ◽  
Roland Zahn ◽  
Kimberly J. McEvers ◽  
Susanne H. C. Baumeister ◽  
...  

ABSTRACT Here, we investigated the containment of virus replication in simian immunodeficiency virus (SIV) infection by CD8+ lymphocytes. Escape mutations in Mamu-A*01 epitopes appeared first in SIV Tat TL8 and then in SIV Gag p11C. The appearance of escape mutations in SIV Gag p11C was coincident with compensatory changes outside of the epitope. Eliminating CD8+ lymphocytes from rhesus monkeys during primary infection resulted in more rapid disease progression that was associated with preservation of canonical epitopes. These results confirm the importance of cytotoxic T cells in controlling viremia and the constraint on epitope sequences that require compensatory changes to go to fixation.


2014 ◽  
Vol 21 (11) ◽  
pp. 1469-1473 ◽  
Author(s):  
Dallas Brown ◽  
Joseph J. Mattapallil

ABSTRACTThe gastrointestinal tract (GIT) is a primary site for human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) infection, replication, and dissemination. After an initial explosive phase of infection, HIV establishes latency. In addition to CD4 T cells, macrophages are readily infected, which can persist for long periods of time. Though macrophages at various systemic sites are infected, those present in the GIT constitute a major cellular reservoir due to the abundance of these cells at mucosal sites. Here, we review some of the important findings regarding what is known about the macrophage reservoir in the gut and explore potential approaches being pursued in the field to reduce this reservoir. The development of strategies that can lead to a functional cure will need to incorporate approaches that can eradicate the macrophage reservoir in the GIT.


2008 ◽  
Vol 82 (11) ◽  
pp. 5618-5630 ◽  
Author(s):  
Ronald S. Veazey ◽  
Paula M. Acierno ◽  
Kimberly J. McEvers ◽  
Susanne H. C. Baumeister ◽  
Gabriel J. Foster ◽  
...  

ABSTRACT Previously we have shown that CD8+ T cells are critical for containment of simian immunodeficiency virus (SIV) viremia and that rapid and profound depletion of CD4+ T cells occurs in the intestinal tract of acutely infected macaques. To determine the impact of SIV-specific CD8+ T-cell responses on the magnitude of the CD4+ T-cell depletion, we investigated the effect of CD8+ lymphocyte depletion during primary SIV infection on CD4+ T-cell subsets and function in peripheral blood, lymph nodes, and intestinal tissues. In peripheral blood, CD8+ lymphocyte-depletion changed the dynamics of CD4+ T-cell loss, resulting in a more pronounced loss 2 weeks after infection, followed by a temporal rebound approximately 2 months after infection, when absolute numbers of CD4+ T cells were restored to baseline levels. These CD4+ T cells showed a markedly skewed phenotype, however, as there were decreased levels of memory cells in CD8+ lymphocyte-depleted macaques compared to controls. In intestinal tissues and lymph nodes, we observed a significantly higher loss of CCR5+ CD45RA− CD4+ T cells in CD8+ lymphocyte-depleted macaques than in controls, suggesting that these SIV-targeted CD4+ T cells were eliminated more efficiently in CD8+ lymphocyte-depleted animals. Also, CD8+ lymphocyte depletion significantly affected the ability to generate SIV Gag-specific CD4+ T-cell responses and neutralizing antibodies. These results reemphasize that SIV-specific CD8+ T-cell responses are absolutely critical to initiate at least partial control of SIV infection.


2005 ◽  
Vol 79 (5) ◽  
pp. 3195-3199 ◽  
Author(s):  
Jean-Daniel Lelièvre ◽  
Frédéric Petit ◽  
Damien Arnoult ◽  
Jean-Claude Ameisen ◽  
Jérôme Estaquier

ABSTRACT Fas-mediated T-cell death is known to occur during human immunodeficiency virus (HIV) infection. In this study, we found that HIV type 1 LAI (HIV-1LAI) primes CD8+ T cells from healthy donors for apoptosis, which occurs after Fas ligation. This effect is counteracted by a broad caspase inhibitor (zVAD-fmk). Fas-mediated cell death does not depend on CD8+ T-cell infection, because it occurred in the presence of reverse transcriptase inhibitors. However, purified CD8+ T cells are sensitive to Fas only in the presence of soluble CD4. Finally, we found that interleukin 7 (IL-7) increases Fas-mediated CD4+ and CD8+ T-cell death induced by HIV-1LAI. Since high levels of IL-7 are a marker of poor prognosis during HIV infection, our data suggest that enhancement of Fas-mediated T-cell death by HIV-1LAI and IL-7 is one of the mechanisms involved in progression to AIDS.


2006 ◽  
Vol 80 (6) ◽  
pp. 3083-3087 ◽  
Author(s):  
Máire F. Quigley ◽  
Kristina Abel ◽  
Bartek Zuber ◽  
Christopher J. Miller ◽  
Johan K. Sandberg ◽  
...  

ABSTRACT Perforin-mediated cytotoxicity is a major effector function of virus-specific CD8 T cells. We have investigated the expression of perforin in the gut, an important site of simian immunodeficiency virus (SIV) pathogenesis, during experimental SIV infection of rhesus macaques. We observed significant increases in perforin protein and mRNA expression levels in the colons of SIV-infected macaques as early as 21 days after infection. However, during chronic infection, despite ongoing viral replication, perforin expression returned to levels similar to those detected in SIV-naïve animals. These findings demonstrate the presence of a robust perforin-positive response in gastrointestinal CD8 T cells during acute, but not chronic, SIV infection.


1994 ◽  
Vol 179 (2) ◽  
pp. 413-424 ◽  
Author(s):  
G Dadaglio ◽  
S Garcia ◽  
L Montagnier ◽  
M L Gougeon

We have analyzed the V beta usage by CD4+ and CD8+ T cells from human immunodeficiency virus (HIV)-infected individuals in response to an in vitro stimulation with the superantigenic erythrogenic toxin A (ETA) of Streptococcus pyogenes. ETA amplifies specifically CD4+ and CD8+ T cells from control donors expressing the V beta 8 and the V beta 12 elements. When peripheral T cells from asymptomatic HIV-infected individuals were stimulated with ETA, there was a complete lack of activation of the V beta 8+ T cell subset, whereas the V beta 12+ T cell subset responded normally to the superantigen. This V beta-specific anergy, which was also observed in response to staphylococcal enterotoxin E (SEE), affected both CD4+ and CD8+ T cells and represented an intrinsic functional defect rather than a specific lack of response to bacterial superantigens since it was also observed after a stimulation with V beta 8 monoclonal antibodies. The V beta 8 anergic T cells did not express interleukin 2 receptors (IL-2Rs) and failed to proliferate in response to exogenous IL-2 or IL-4, suggesting that this anergy was not a reversible process, at least by the use of these cytokines. The unresponsiveness of the V beta 8 T cell subset is frequent since it was found in 56% of the patients studied, and comparison of the clinical status of responder vs. anergic patients indicated that the only known common factor between them was HIV infection. In addition, it is noteworthy that the anergy of the V beta 8 subset may be a very early phenomenon since it was found in a patient at Centers for Disease Control stage I of the disease. These data provide evidence that a dominant superantigen may be involved in the course of HIV infection and that the contribution of HIV has to be considered.


2018 ◽  
Vol 2 ◽  
pp. 105 ◽  
Author(s):  
Andrew Mwale ◽  
Annemarie Hummel ◽  
Leonard Mvaya ◽  
Raphael Kamng'ona ◽  
Elizabeth Chimbayo ◽  
...  

Background: HIV infection is associated with increased risk to lower respiratory tract infections (LRTI). However, the impact of HIV infection on immune cell populations in the lung is not well defined. We sought to comprehensively characterise the impact of HIV infection on immune cell populations in the lung. Methods: Twenty HIV-uninfected controls and 17 HIV-1 infected ART-naïve adults were recruited from Queen Elizabeth Central Hospital, Malawi. Immunophenotyping of lymphocyte and myeloid cell populations was done on bronchoalveolar lavage fluid and peripheral blood cells. Results: We found that the numbers of CD8 + T cells, B cells and gamma delta T cells were higher in BAL fluid of HIV-infected adults compared to HIV-uninfected controls (all p<0.05). In contrast, there was no difference in the numbers of alveolar CD4 + T cells in HIV-infected adults compared to HIV-uninfected controls (p=0.7065). Intermediate monocytes were the predominant monocyte subset in BAL fluid (HIV-, 63%; HIV+ 81%), while the numbers of classical monocytes was lower in HIV-infected individuals compared to HIV-uninfected adults (1 × 10 5 vs. 2.8 × 10 5 cells/100ml of BAL fluid, p=0.0001). The proportions of alveolar macrophages and myeloid dendritic cells was lower in HIV-infected adults compared to HIV-uninfected controls (all p<0.05). Conclusions: Chronic HIV infection is associated with broad alteration of immune cell populations in the lung, but does not lead to massive depletion of alveolar CD4 + T cells. Disruption of alveolar immune cell homeostasis likely explains in part the susceptibility for LRTIs in HIV-infected adults.


2020 ◽  
Author(s):  
Meropi Aravantinou ◽  
Olga Mizenina ◽  
Thilo Brill ◽  
Jessica Kenney ◽  
Christine Timmons ◽  
...  

ABSTRACTDevelopment of an effective human immunodeficiency virus (HIV) vaccine is among the highest priorities in the biomedical research agenda. Adjuvants enhance vaccine efficacy, but in the case of HIV, strong or inappropriate immune activation may undermine protection by increasing HIV susceptibility. Co-infection with immunomodulatory pathogens may also impact vaccine efficacy. In the rhesus macaque rectal SIVΔNef live attenuated vaccine model, we utilized a low virulence HSV-2 infection and the double-stranded RNA viral mimic polyICLC as tools to probe the effects of distinct types of immune activation on HIV vaccine efficacy and explore novel correlates of protection from wild type SIV. Rectally administered HSV-2 and polyICLC impacted the protection conferred by mucosal SIVΔNef vaccination by favoring partial protection in animals with breakthrough infection following virulent SIV challenge (“Controllers”). However, SIVΔNef persistence in blood and tissues did not predict protection in this rectal immunization and challenge model. Non-controllers had similar SIVΔNef viremia as completely protected macaques, and while they tended to have less replication competent SIVΔNef in lymph nodes, controllers had no recoverable virus in the lymph nodes. Non-controllers differed from protected macaques immunologically by having a greater frequency of pro-inflammatory CXCR3+CCR6+ CD4 T cells in blood and a monofunctional IFNγ-dominant CD8 T cell response in lymph nodes. Controller phenotype was associated with heightened IFNα production during acute SIV infection and a greater frequency of CXCR5+ CD4 T cells in blood pre-challenge despite a lower frequency of cells with the T follicular helper (Tfh) cell phenotype in blood and lymph nodes. Our results establish novel correlates of immunological control of SIV infection while reinforcing the potential importance of T cell functionality and location in SIVΔNef efficacy. Moreover, this work highlights that triggering of mucosal immunity can aid mucosal vaccine strategies rather than undermine protection.AUTHOR SUMMARYAn efficacious HIV vaccine is essential to contain the HIV pandemic. Vaccine-mediated protection from HIV may be either enhanced or obstructed by mucosal immune activation; thus, the impact of adjuvants and underlying co-infections that lead to immune activation needs to be evaluated. Using the SIV macaque model, we set out to study the impact of underlying infection with HSV-2 or treatment with the adjuvant polyICLC on rectal immunization with the live attenuated vaccine SIVΔNef. We found that neither stimulus impacted complete protection from SIV; however, the combination of HSV-2 and polyICLC improved control of infection in animals that were not completely protected. Compared with non-controller macaques, controllers had less inflammatory T cells before SIV challenge as well as greater gene expression of IFNα and more functional SIV-specific T cells after infection. The results add to our understanding of the mechanisms of SIVΔNef protection and demonstrate that mucosal immune activation does not necessarily undermine protection in mucosal vaccination against HIV.


2007 ◽  
Vol 81 (15) ◽  
pp. 8009-8015 ◽  
Author(s):  
Yue Sun ◽  
Sallie R. Permar ◽  
Adam P. Buzby ◽  
Norman L. Letvin

ABSTRACT It has long been appreciated that CD4+ T lymphocytes are dysfunctional in human immunodeficiency virus (HIV)/simian immunodeficiency virus (SIV)-infected individuals, and it has recently been shown that HIV/SIV infections are associated with a dramatic early destruction of memory CD4+ T lymphocytes. However, the relative contributions of CD4+ T-lymphocyte dysfunction and loss to immune dysregulation during primary HIV/SIV infection have not been fully elucidated. In the current study, we evaluated CD4+ T lymphocytes and their functional repertoire during primary SIVmac251 infection in rhesus monkeys. We show that the extent of loss of memory CD4+ T lymphocytes and staphylococcal enterotoxin B-stimulated cytokine production by total CD4+ T lymphocytes during primary SIVmac251 infection is tightly linked in a cohort of six rhesus monkeys to set point plasma viral RNA levels, with greater loss and dysfunction being associated with higher steady-state viral replication. Moreover, in exploring the mechanism underlying this phenomenon, we demonstrate that the loss of functional CD4+ T lymphocytes during primary SIVmac251 infection is associated with both a selective depletion of memory CD4+ T cells and a loss of the functional capacity of the memory CD4+ T lymphocytes that escape viral destruction.


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