scholarly journals High Levels of TRIM5a Are Associated with Xenophagy in HIV-1-Infected Long-Term Nonprogressors

Cells ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 1207
Author(s):  
Fabiola Ciccosanti ◽  
Marco Corazzari ◽  
Rita Casetti ◽  
Alessandra Amendola ◽  
Diletta Collalto ◽  
...  

Autophagy is a lysosomal-dependent degradative mechanism essential in maintaining cellular homeostasis, but it is also considered an ancient form of innate eukaryotic fighting against invading microorganisms. Mounting evidence has shown that HIV-1 is a critical target of autophagy that plays a role in HIV-1 replication and disease progression. In a special subset of HIV-1-infected patients that spontaneously and durably maintain extremely low viral replication, namely, long-term nonprogressors (LTNP), the resistance to HIV-1-induced pathogenesis is accompanied, in vivo, by a significant increase in the autophagic activity in peripheral blood mononuclear cells. Recently, a new player in the battle of autophagy against HIV-1 has been identified, namely, tripartite motif protein 5α (TRIM5α). In vitro data demonstrated that TRIM5α directly recognizes HIV-1 and targets it for autophagic destruction, thus protecting cells against HIV-1 infection. In this paper, we analyzed the involvement of this factor in the control of HIV-1 infection through autophagy, in vivo, in LTNP. The results obtained showed significantly higher levels of TRIM5α expression in cells from LTNP with respect to HIV-1-infected normal progressor patients. Interestingly, the colocalization of TRIM5α and HIV-1 proteins in autophagic vacuoles in LTNP cells suggested the participation of TRIM5α in the autophagy containment of HIV-1 in LTNP. Altogether, our results point to a protective role of TRIM5α in the successful control of the chronic viral infection in HIV-1-controllers through the autophagy mechanism. In our opinion, these findings could be relevant in fighting against HIV-1 disease, because autophagy inducers might be employed in combination with antiretroviral drugs.

Blood ◽  
1983 ◽  
Vol 62 (4) ◽  
pp. 869-872 ◽  
Author(s):  
JW Singer ◽  
A Keating ◽  
R Ramberg ◽  
R McGuffin ◽  
JE Sanders ◽  
...  

Abstract This article describes the course of a patient who received an allogeneic marrow graft from his HLA-identical sister for acute lymphoblastic leukemia in second remission. In the second month after grafting, marrow aspirates showed the presence of 7%-10% lymphoblasts. In addition, cytogenetic examination indicated the persistence of host cells. Thereafter, the patient had morphologically normal marrow examinations, with no evidence for recurrent leukemia. In addition, stable hematopoietic chimerism in both the lymphoid and myeloid cell lines has persisted for over 5 yr. Between 20% and 50% of phytohemagglutinin-stimulated peripheral blood mononuclear cells were host-derived on repeated studies. A marrow sample 4 yr after transplantation was established in long-term culture and produced 2% host granulocyte-macrophage colonies at its inception, but 24% host colonies by week 4. Despite this persistent chimerism, no in vitro or in vivo abnormalities of hematopoiesis have been detected.


2019 ◽  
Vol 116 (21) ◽  
pp. 10504-10509 ◽  
Author(s):  
Fabian Schmidt ◽  
Brandon F. Keele ◽  
Gregory Q. Del Prete ◽  
Dennis Voronin ◽  
Christine M. Fennessey ◽  
...  

To replicate in a new host, lentiviruses must adapt to exploit required host factors and evade species-specific antiviral proteins. Understanding how host protein variation drives lentivirus adaptation allowed us to expand the host range of HIV-1 to pigtail macaques. We have previously derived a viral swarm (in the blood of infected animals) that can cause AIDS in this new host. To further exploit this reagent, we generated infectious molecular clones (IMCs) from the viral swarm. We identified clones with high replicative capacity in pigtail peripheral blood mononuclear cells (PBMC) in vitro and used in vivo replication to select an individual IMC, named stHIV-A19 (for simian tropic HIV-1 clone A19), which recapitulated the phenotype obtained with the viral swarm. Adaptation of HIV-1 in macaques led to the acquisition of amino acid changes in viral proteins, such as capsid (CA), that are rarely seen in HIV-1–infected humans. Using stHIV-A19, we show that these CA changes confer a partial resistance to the host cell inhibitor Mx2 from pigtail macaques, but that complete resistance is associated with a fitness defect. Adaptation of HIV-1 to a new host will lead to a more accurate animal model and a better understanding of virus–host interactions.


1994 ◽  
Vol 5 (1) ◽  
pp. 51-55 ◽  
Author(s):  
G. Antonelli ◽  
F. Dianzani ◽  
D. Bellarosa ◽  
O. Turriziani ◽  
E. Riva ◽  
...  

Both 3′-azido-3′-deoxythymidine (AZT) and 2′,3′-dideoxynosine (ddl) strongly inhibit the replication of human immunodeficiency virus type 1 (HIV-1). Here, it is shown that combination of AZT and ddl at concentrations that are readily achievable in vivo synergistically inhibit HIV-1 replication in C8166 cells and peripheral blood mononuclear cells. The synergism is significant even when the effect of AZT and ddl alone was negligible. Our findings show that AZT-resistance is less likely to occur when a combination of AZT and ddl is used. Particularly, generation of AZT-resistant strains by in vitro selection is prevented, or delayed, by the combination of AZT plus ddl. Taken together these observations provide a rationale for combination of AZT and ddl in the therapy of AIDS patients.


2016 ◽  
Vol 61 (1) ◽  
Author(s):  
Subhra Mandal ◽  
Michael Belshan ◽  
Ashley Holec ◽  
You Zhou ◽  
Christopher J. Destache

ABSTRACT Among various FDA-approved combination antiretroviral drugs (cARVs), emtricitabine (FTC) has been a very effective nucleoside reverse transcriptase inhibitor. Thus far, FTC is the only deoxycytidine nucleoside analog. However, a major drawback of FTC is its large volume distribution (averaging 1.4 liters/kg) and short plasma half-life (8 to 10 h), necessitating a high daily dosage. Thus, we propose an innovative fabrication method of loading FTC in poly(lactic-co-glycolic acid) polymeric nanoparticles (FTC-NPs), potentially overcoming these drawbacks. Our nanoformulation demonstrated enhanced FTC loading (size of <200 nm and surface charge of −23 mV) and no to low cytotoxicity with improved biocompatibility compared to those with FTC solution. An ex vivo endosomal release assay illustrated that NP entrapment prolongs FTC release over a month. Intracellular retention studies demonstrate sustained FTC retention over time, with approximately 8% (24 h) to 68% (96 h) release with a mean retention of ∼0.74 μg of FTC/105 cells after 4 days. An in vitro HIV-1 inhibition study demonstrated that FTC-NP treatment results in a 50% inhibitory concentration (IC50) ∼43 times lower in TZM-bl cells (0.00043 μg/ml) and ∼3.7 times lower (0.009 μg/ml) in peripheral blood mononuclear cells (PBMCs) than with FTC solution (TZM-bl cells, 0.01861, and PBMCs, 0.033 μg/ml). Further, on primary PBMCs, FTC-NPs also illustrate an HIV-1 infection blocking efficacy comparable to that of FTC solution. All the above-described studies substantiate that FTC nanoformulation prolongs intracellular FTC concentration and inhibition of HIV infection. Therefore, FTC-NPs potentially could be a long-acting, stable formulation to ensure once-biweekly dosing to prevent or treat HIV infection.


2001 ◽  
Vol 75 (11) ◽  
pp. 4999-5008 ◽  
Author(s):  
Lee Bacheler ◽  
Susan Jeffrey ◽  
George Hanna ◽  
Richard D'Aquila ◽  
Lany Wallace ◽  
...  

ABSTRACT Efavirenz (also known as DMP 266 or SUSTIVA) is a potent nonnucleoside inhibitor of human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) activity and of HIV-1 replication in vitro and in vivo. Most patients on efavirenz-containing regimens have sustained antiviral responses; however, rebounds in plasma viral load have been observed in some patients in association with the emergence of mutant strains of HIV-1. Virus isolates from the peripheral blood mononuclear cells (PBMCs) of patients with such treatment failures, as well as recombinant viruses incorporating viral sequences derived from patient plasma, show reduced in vitro susceptibility to efavirenz in association with mutations in the RT gene encoding K103N, Y188L, or G190S/E substitutions. Patterns of RT gene mutations and in vitro susceptibility were similar in plasma virus and in viruses isolated from PBMCs. Variant strains of HIV-1 constructed by site-directed mutagenesis confirmed the role of K103N, G190S, and Y188L substitutions in reduced susceptibility to efavirenz. Further, certain secondary mutations (V106I, V108I, Y181C, Y188H, P225H, and F227L) conferred little resistance to efavirenz as single mutations but enhanced the level of resistance of viruses carrying these mutations in combination with K103N or Y188L. Viruses with K103N or Y188L mutations, regardless of the initial selecting nonnucleoside RT inhibitor (NNRTI), exhibited cross-resistance to all of the presently available NNRTIs (efavirenz, nevirapine, and delavirdine). Some virus isolates from nevirapine or delavirdine treatment failures that lacked K103N or Y188L mutations remained susceptible to efavirenz in vitro, although the clinical significance of this finding is presently unclear.


2019 ◽  
Vol 1 (1) ◽  
pp. 85-90
Author(s):  
M. N. Nosik ◽  
K. A. Ryzhov ◽  
A. V. Potapova

Aim. To study how female hormones included in oral contraceptives (β-estradiol and progesteron) affect HIV-1 replication and efficacy of antiviral drugs. Material and methods. Peripheral blood mononuclear cells (PBMC) and cell lines MT-4, Jurkat were infected with HIV-1 (subtype A6). Afterwards the cells were cultured for 6 days in the presence of β-estradiol/progesteron with or without the presence of antiretroviral drugs Lamivudin (3TC), Etravirin(ETR) and Indinavir (IDV), which are widely used for HIV treatment. Virus production was monitored by p24 levels in culture supernatants on day 6. The experemints were performed in eight repetitions. Results. There was a 1,3-1,8-fold increase of virus replication in the presence of high concentrations of both hormones (26,136 μg/ml). Incomplete suppression of viral replication was observed when infected cells were co-cultivated in the presence of hormones (26 μg, 136 μg) and antiretroviral drugs. The mean suppression rate of viral replication for β-estradiol was 77.3% and 69.8% for progesterone. However, in the absence of hormones the virus production was completely suppressed by those drugs. Conclusion. The high concentrations of steroid hormones induce HIV-1 replication and as a result reduce the efficacy of antiretroviral drugs NVP and IDV in vitro. Thus it is advisable for women at high risk of HIV infection to monitor hormone levels that change during the menstrual cycle and pregnancy before prescribing hormonal contraception.


Blood ◽  
1983 ◽  
Vol 62 (4) ◽  
pp. 869-872
Author(s):  
JW Singer ◽  
A Keating ◽  
R Ramberg ◽  
R McGuffin ◽  
JE Sanders ◽  
...  

This article describes the course of a patient who received an allogeneic marrow graft from his HLA-identical sister for acute lymphoblastic leukemia in second remission. In the second month after grafting, marrow aspirates showed the presence of 7%-10% lymphoblasts. In addition, cytogenetic examination indicated the persistence of host cells. Thereafter, the patient had morphologically normal marrow examinations, with no evidence for recurrent leukemia. In addition, stable hematopoietic chimerism in both the lymphoid and myeloid cell lines has persisted for over 5 yr. Between 20% and 50% of phytohemagglutinin-stimulated peripheral blood mononuclear cells were host-derived on repeated studies. A marrow sample 4 yr after transplantation was established in long-term culture and produced 2% host granulocyte-macrophage colonies at its inception, but 24% host colonies by week 4. Despite this persistent chimerism, no in vitro or in vivo abnormalities of hematopoiesis have been detected.


2006 ◽  
Vol 80 (21) ◽  
pp. 10663-10674 ◽  
Author(s):  
Andrea Crotti ◽  
Francesca Neri ◽  
Davide Corti ◽  
Silvia Ghezzi ◽  
Silvia Heltai ◽  
...  

ABSTRACT Infection with human immunodeficiency virus (HIV)-encoding defective nef variants may contribute to a relatively benign course of disease in a minority of long-term nonprogressors (LTNP). We have examined the functions of nef alleles from six individuals belonging to the same cohort of hemophiliacs infected with HIV-1 prior to 1985 and classified as LTNP in 1995. Three out of six individuals have progressed to HIV disease (late progressors [LP]), whereas the three remainders have maintained their LTNP status at least up to 2003. The nef alleles were obtained from both plasma virus and peripheral blood mononuclear cells of all six individuals in 1995 and 1998. The proportion of sequences containing mutations not yielding Nef expression significantly diminished in 1998 versus that in 1995. Several previously defined functional regions of intact nef alleles were highly conserved. However, the major variant obtained in 1998 from plasma RNA of five out of six individuals significantly reduced HIV infectivity/replication and impaired Nef-mediated CD4 but not major histocompatibility complex class I antigen down-modulation from the cell surface. Thus, functional alterations of the nef gene are present in both LP and LTNP, suggesting that Nef defectiveness in vitro is not necessarily associated with the long-term maintenance of LTNP status. Of interest is the fact that isolates from three out of three LP showed a dual CCR5/CXCR4 coreceptor use (R5X4), in contrast to those from LTNP, which were exclusively R5. Thus, in vivo evolution of gp120 Env to CXCR4 use appears to be associated with HIV disease progression in individuals infected with nef-defective viruses.


2020 ◽  
Author(s):  
Hacer Kuzu Okur ◽  
Koray Yalcin ◽  
Cihan Tastan ◽  
Sevda Demir ◽  
Bulut Yurtsever ◽  
...  

UNSTRUCTURED Dornase alfa, the recombinant form of the human DNase I enzyme, breaks down neutrophil extracellular traps (NET) that include a vast amount of DNA fragments, histones, microbicidal proteins and oxidant enzymes released from necrotic neutrophils in the highly viscous mucus of cystic fibrosis patients. Dornase alfa has been used for decades in patients with cystic fibrosis to reduce the viscoelasticity of respiratory tract secretions, to decrease the severity of respiratory tract infections, and to improve lung function. Previous studies have linked abnormal NET formations to lung diseases, especially to acute respiratory distress syndrome (ARDS). Coronavirus disease 2019 (COVID-19) pandemic affected more than two million people over the world, resulting in unprecedented health, social and economic crises. The COVID-19, viral pneumonia that progresses to ARDS and even multiple organ failure, is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). High blood neutrophil levels are an early indicator of SARS-CoV-2 infection and predict severe respiratory diseases. A similar mucus structure is detected in COVID-19 patients due to the accumulation of excessive NET in the lungs. Here, we show our preliminary results with dornase alfa that may have an in-vitro anti-viral effect against SARS-CoV-2 infection in a bovine kidney cell line, MDBK without drug toxicity on healthy adult peripheral blood mononuclear cells. In this preliminary study, we also showed that dornase alfa can promote clearance of NET formation in both an in-vitro and three COVID-19 cases who showed clinical improvement in radiological analysis (2-of-3 cases), oxygen saturation (SpO2), respiratory rate, disappearing of dyspnea and coughing.


Vaccines ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 29
Author(s):  
Laia Bosch-Camós ◽  
Elisabet López ◽  
María Jesús Navas ◽  
Sonia Pina-Pedrero ◽  
Francesc Accensi ◽  
...  

The development of subunit vaccines against African swine fever (ASF) is mainly hindered by the lack of knowledge regarding the specific ASF virus (ASFV) antigens involved in protection. As a good example, the identity of ASFV-specific CD8+ T-cell determinants remains largely unknown, despite their protective role being established a long time ago. Aiming to identify them, we implemented the IFNγ ELISpot as readout assay, using as effector cells peripheral blood mononuclear cells (PBMCs) from pigs surviving experimental challenge with Georgia2007/1. As stimuli for the ELISpot, ASFV-specific peptides or full-length proteins identified by three complementary strategies were used. In silico prediction of specific CD8+ T-cell epitopes allowed identifying a 19-mer peptide from MGF100-1L, as frequently recognized by surviving pigs. Complementarily, the repertoire of SLA I-bound peptides identified in ASFV-infected porcine alveolar macrophages (PAMs), allowed the characterization of five additional SLA I-restricted ASFV-specific epitopes. Finally, in vitro stimulation studies using fibroblasts transfected with plasmids encoding full-length ASFV proteins, led to the identification of MGF505-7R, A238L and MGF100-1L as promiscuously recognized antigens. Interestingly, each one of these proteins contain individual peptides recognized by surviving pigs. Identification of the same ASFV determinants by means of such different approaches reinforce the results presented here.


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