HIV-1-Infected CD4+ T Cells Facilitate Latent Infection of Resting CD4+ T Cells through Cell-Cell Contact

AbstractThe HIV-1 envelope (Env) is an essential determinant of viral infectivity, tropism and spread between T cells. Lentiviral Env contain an unusually long 150 amino acid cytoplasmic tail (EnvCT) but the function of the EnvCT and conserved domains within it remain largely uncharacterised. Here we identified a highly conserved tryptophan motif at position 757 (W757) in the LLP-2 alpha helix of the EnvCT as a key determinant for HIV-1 replication and spread between T cells. Strikingly we find that mutating W757 had wide-ranging consequences including altering Env mobility in the plasma membrane, preventing Env and Gag recruitment to sites of cell-cell contact for virological synapse (VS) formation and cell-cell spread, and impeding viral fusion. Notably, W757 was also required for efficient virus budding, revealing a previously unappreciated role for the EnvCT in regulating HIV-1 assembly and egress. We conclude that W757 is a key residue that stabilises the structural integrity and function of Env, consistent with the recent model that this region of the EnvCT acts as a critical supporting baseplate for Env.

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A Conserved Tryptophan in the Envelope Cytoplasmic Tail Regulates HIV-1 Assembly and Spread

Viruses ◽

10.3390/v14010129 ◽

2022 ◽

Vol 14 (1) ◽

pp. 129

Author(s):

Xenia Snetkov ◽

Tafhima Haider ◽

Dejan Mesner ◽

Nicholas Groves ◽

Schuyler B. van Engelenburg ◽

...

Keyword(s):

T Cells ◽

Single Molecule ◽

Virus Assembly ◽

Alpha Helix ◽

Cytoplasmic Tail ◽

Virological Synapse ◽

Cell Contact ◽

Viral Spread ◽

Hiv 1 ◽

Cell Cell

The HIV-1 envelope (Env) is an essential determinant of viral infectivity, tropism and spread between T cells. Lentiviral Env contain an unusually long 150 amino acid cytoplasmic tail (EnvCT), but the function of the EnvCT and many conserved domains within it remain largely uncharacterised. Here, we identified a highly conserved tryptophan motif at position 757 (W757) in the LLP-2 alpha helix of the EnvCT as a key determinant for HIV-1 replication and spread between T cells. Alanine substitution at this position potently inhibited HIV-1 cell–cell spread (the dominant mode of HIV-1 dissemination) by preventing recruitment of Env and Gag to sites of cell–cell contact, inhibiting virological synapse (VS) formation and spreading infection. Single-molecule tracking and super-resolution imaging showed that mutation of W757 dysregulates Env diffusion in the plasma membrane and increases Env mobility. Further analysis of Env function revealed that W757 is also required for Env fusion and infectivity, which together with reduced VS formation, result in a potent defect in viral spread. Notably, W757 lies within a region of the EnvCT recently shown to act as a supporting baseplate for Env. Our data support a model in which W757 plays a key role in regulating Env biology, modulating its temporal and spatial recruitment to virus assembly sites and regulating the inherent fusogenicity of the Env ectodomain, thereby supporting efficient HIV-1 replication and spread.

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Contact-Induced Mitochondrial Polarization Supports HIV-1 Virological Synapse Formation

Journal of Virology ◽

10.1128/jvi.02425-14 ◽

2014 ◽

Vol 89 (1) ◽

pp. 14-24 ◽

Cited By ~ 16

Author(s):

Elisabetta Groppelli ◽

Shimona Starling ◽

Clare Jolly

Keyword(s):

T Cells ◽

T Cell ◽

T Lymphocytes ◽

Virological Synapse ◽

Cell Contact ◽

Target Cells ◽

Cell Contacts ◽

Cell Spread ◽

Hiv 1 ◽

Cell Cell

ABSTRACTRapid HIV-1 spread between CD4 T lymphocytes occurs at retrovirus-induced immune cell contacts called virological synapses (VS). VS are associated with striking T cell polarization and localized virus budding at the site of contact that facilitates cell-cell spread. In addition to this, spatial clustering of organelles, including mitochondria, to the contact zone has been previously shown. However, whether cell-cell contact specifically induces dynamic T cell remodeling during VS formation and what regulates this process remain unclear. Here, we report that contact between an HIV-1-infected T cell and an uninfected target T cell specifically triggers polarization of mitochondria concomitant with recruitment of the major HIV-1 structural protein Gag to the site of cell-cell contact. Using fixed and live-cell imaging, we show that mitochondrial and Gag polarization in HIV-1-infected T cells occurs within minutes of contact with target T cells, requires the formation of stable cell-cell contacts, and is an active, calcium-dependent process. We also find that perturbation of mitochondrial polarization impairs cell-cell spread of HIV-1 at the VS. Taken together, these data suggest that HIV-1-infected T cells are able to sense and respond to contact with susceptible target cells and undergo dynamic cytoplasmic remodeling to create a synaptic environment that supports efficient HIV-1 VS formation between CD4 T lymphocytes.IMPORTANCEHIV-1 remains one of the major global health challenges of modern times. The capacity of HIV-1 to cause disease depends on the virus's ability to spread between immune cells, most notably CD4 T lymphocytes. Cell-cell transmission is the most efficient way of HIV-1 spread and occurs at the virological synapse (VS). The VS forms at the site of contact between an infected cell and an uninfected cell and is characterized by polarized assembly and budding of virions and clustering of cellular organelles, including mitochondria. Here, we show that cell-cell contact induces rapid recruitment of mitochondria to the contact site and that this supports efficient VS formation and consequently cell-cell spread. Additionally, we observed that cell-cell contact induces a mitochondrion-dependent increase in intracellular calcium, indicative of cellular signaling. Taken together, our data suggest that VS formation is a regulated process and thus a potential target to block HIV-1 cell-cell spread.

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Proliferation of HIV-infected renal epithelial cells following virus acquisition from infected macrophages

10.1101/2020.03.27.011916 ◽

2020 ◽

Author(s):

Kelly Hughes ◽

Guray Akturk ◽

Sacha Gnjatic ◽

Benjamin Chen ◽

Mary Klotman ◽

...

Keyword(s):

T Cells ◽

Cd4 T Cells ◽

Inflammatory Responses ◽

Live Imaging ◽

Cell Contact ◽

Renal Cells ◽

Virus Acquisition ◽

Primary Monocyte ◽

Design And Methods ◽

Hiv 1

ABSTRACTObjectivesHIV-1 can infect and persist in different organs and tissues, resulting in the generation of multiple viral compartments and reservoirs. Increasing evidence supports the kidney as such a reservoir. Previous work demonstrated that HIV-1 infected CD4+ T-cells transfer virus to renal tubule epithelial (RTE) cells through cell-to-cell contact. In addition to CD4+ T-cells, macrophages represent the other major target of HIV-1. Renal macrophages induce and regulate inflammatory responses and are critical to homeostatic regulation of the kidney environment. Combined with their ability to harbor virus, macrophages may also play an important role in the spread of HIV-1 infection in the kidney.Design and MethodsMultiparametric histochemistry analysis was performed on kidney biopsies from individuals with HIV-1 associated nephropathy (HIVAN). Primary monocyte-derived macrophages were infected with a (GFP)-expressing replication competent HIV-1. HIV-1 transfer from macrophages to RTE cells was carried out in a co-culture system and evaluated by fluorescence-microscopy and flow-cytometry. Live imaging was performed to assess the fate of HIV-1 infected RTE cells over time.ResultsWe show that macrophages are abundantly present in the renal inflammatory infiltrate of individuals with HIVAN. We observed contact-dependent HIV-1 transfer from infected macrophages to both primary and immortalized renal cells. Live imaging of HIV-1 infected RTE cells revealed four different fates: proliferation, hypertrophy, latency and cell death.ConclusionsOur study suggests that macrophages may play a role in the dissemination of HIV-1 in the kidney and that proliferation of infected renal cells may contribute to HIV-1 persistence in this compartment.

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Platelets regulate CD4+ T-cell differentiation via multiple chemokines in humans

Thrombosis and Haemostasis ◽

10.1160/th11-01-0020 ◽

2011 ◽

Vol 106 (08) ◽

pp. 353-362 ◽

Cited By ~ 63

Author(s):

Norbert Gerdes ◽

Linjing Zhu ◽

Maria Ersoy ◽

Andreas Hermansson ◽

Paul Hjemdahl ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

T Cell Activation ◽

Cd4 T Cells ◽

Cell Activation ◽

Cytokine Production ◽

Cd4 T Cell ◽

Cell Contact ◽

Direct Cell ◽

Cell Cell

SummaryAtherosclerosis is an inflammatory and thrombotic disease. Both platelets and lymphocytes play important roles in atherogenesis. However, information on their interaction is limited. We therefore studied how platelets regulate CD4+ T cell activation and differentiation. Human CD4+ T cells and autologous platelets were co-cultured. Platelets concentration-dependently enhanced anti-CD3/CD28-induced IFNγ production by CD4+ T cells, but attenuated their proliferation. Abrogation of heterotypic cell-cell contact partially reversed the enhancement, and supernatant from activated platelets partially mimicked the enhancement, suggesting that platelets exert their effects via both soluble mediators and direct cell-cell contact. Platelets enhanced the production of IL-10 and cytokines characteristic for type 1 T helper (TH1) (IFNγ/ TNFα) and TH17 (IL-17) cells, but influenced TH2 cytokines (IL-4/IL-5) little. The cytokine responses were accompanied by enhanced TH1/TH17/TReg differentiation. Using neutralising antibodies and recombinant PF4, RANTES, and TGFβ, we found that platelet-derived PF4 and RANTES enhanced both pro- and anti-inflammatory cytokine production, whilst recombinant TGFβ enhanced IL-10 but not TNFα production. In conclusion, platelets enhance the differentiation and cytokine production of anti-CD3/CD28-stimulated CD4+ T cells via both multiple chemokines and direct cell-cell contact. Our study provides new insights into the cross-talk between thrombosis and adaptive immunity, and indicates that platelets can enhance T-effector cell development.

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Manipulating CD4+T cells by optical tweezers for the initiation of cell-cell transfer of HIV-1

Journal of Biophotonics ◽

10.1002/jbio.200900102 ◽

2010 ◽

Vol 3 (4) ◽

pp. 216-223 ◽

Cited By ~ 19

Author(s):

Gregory P. McNerney ◽

Wolfgang Hübner ◽

Benjamin K. Chen ◽

Thomas Huser

Keyword(s):

T Cells ◽

Optical Tweezers ◽

Cd4 T Cells ◽

Cell Transfer ◽

Hiv 1 ◽

Cell Cell

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Prestimulation of CD2 confers resistance to HIV-1 latent infection in blood resting CD4 T cells

iScience ◽

10.1016/j.isci.2021.103305 ◽

2021 ◽

pp. 103305

Author(s):

Sijia He ◽

Jia Guo ◽

Yajing Fu ◽

Mark Spear ◽

Chaolong Qin ◽

...

Keyword(s):

T Cells ◽

Cd4 T Cells ◽

Latent Infection ◽

Hiv 1

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Activated T cells induce expression of B7/BB1 on normal or leukemic B cells through a CD40-dependent signal.

Journal of Experimental Medicine ◽

10.1084/jem.177.4.925 ◽

1993 ◽

Vol 177 (4) ◽

pp. 925-935 ◽

Cited By ~ 422

Author(s):

E A Ranheim ◽

T J Kipps

Keyword(s):

Cell Proliferation ◽

T Cells ◽

B Cells ◽

B Cell ◽

Cd4 T Cells ◽

Cell Phenotype ◽

Cell Contact ◽

Activated T Cells ◽

Antigen Presenting ◽

Cell Cell

Cognate interactions between antigen-presenting B and T cells play crucial roles in immunologic responses. T cells that have been activated via the crosslinking of CD3 are able to induce B cell proliferation and immunoglobulin secretion in a major histocompatibility complex-unrestricted and contact-dependent manner. We find that such activated human CD4+ T cells, but not control Ig-treated T cells, may induce normal or leukemic B cells to express B7/BB1 and significantly higher levels of CD54 intercellular adhesion molecule 1 via a process that also requires direct cell-cell contact. To discern what cell surface molecule(s) may be responsible for signalling B cells to express B7/BB1, we added various monoclonal antibodies (mAbs) specific for T or B cell accessory molecules or control mAbs to cocultures of alpha-CD3-activated T cells and resting B cells. We find that only alpha-CD40 mAbs can significantly inhibit the increased expression of B7/BB1, suggesting that the ligand for CD40 expressed on activated T cells may be an important inducer of B7/BB1 expression. Subsequent experiments in fact demonstrate that alpha-CD40 mAbs, but not control mAbs, induce changes in B cell phenotype similar to those induced by activated T cells when the mAbs are presented on Fc gamma RII (CDw32)-expressing L cells. These phenotypic changes have significant effects on B cell function. Whereas chronic lymphocytic leukemia (CLL) B cells normally are very poor stimulators in allogeneic mixed lymphocyte reactions (MLRs), CLL-B cells preactivated via CD40 crosslinking are significantly better presenters of alloantigen, affecting up to 30-fold-greater stimulation of T cell proliferation than that induced by control treated or nontreated CLL-B cells. Similarly, the MLR of T cells stimulated by allogeneic nonleukemic B cells can be enhanced significantly if the stimulator B cells are preactivated via CD40 crosslinking. The enhanced MLR generated by such preactivated B cells may be inhibited by blocking B7/BB1-CD28 interaction with CTLA4Ig. These studies demonstrate a novel, CD40-dependent pathway for inducing B cell expression of B7/BB1 and enhancing B cell antigen-presenting cell activity that can be initiated via cell-cell contact with alpha-CD3-stimulated CD4+ T cells.

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Mode of Transmission Affects the Sensitivity of Human Immunodeficiency Virus Type 1 to Restriction by Rhesus TRIM5α

Journal of Virology ◽

10.1128/jvi.01046-08 ◽

2008 ◽

Vol 82 (22) ◽

pp. 11117-11128 ◽

Cited By ~ 55

Author(s):

Max W. Richardson ◽

Richard G. Carroll ◽

Matthew Stremlau ◽

Nikolay Korokhov ◽

Laurent M. Humeau ◽

...

Keyword(s):

Human Immunodeficiency Virus ◽

T Cells ◽

Cd4 T Cells ◽

Hiv Transmission ◽

Human Cells ◽

Cell Contact ◽

Hiv Therapy ◽

Immunodeficiency Virus ◽

Hiv 1

ABSTRACT Rhesus TRIM5α (rhTRIM5α), but not human TRIM5α (huTRIM5α), potently inhibits human immunodeficiency virus (HIV) infection and is thus a potentially valuable therapeutic tool. Primary human CD4 T cells engineered to express rhTRIM5α were highly resistant to cell-free HIV type 1 (HIV-1) infection. However, when cocultured with unmodified T cells, rhTRIM5α-expressing cells became highly permissive to HIV-1 infection. Physical separation of rhTRIM5α-expressing cells and unmodified cells revealed that rhTRIM5α efficiently restricts cell-free but not cell-associated HIV transmission. Furthermore, we observed that HIV-infected human cells could infect rhesus CD4 T cells by cell-to-cell contact, but the infection was self-limiting. Subsequently, we noted that a spreading infection ensued when HIV-1-infected rhTRIM5α-expressing human cells were cultured with huTRIM5α- but not rhTRIM5α-expressing cells. Our results suggest that cell-associated HIV transmission in humans is blocked only when both donor and recipient cells express rhTRIM5α. These studies further define the role of rhTRIM5α in cell-free and cell-associated HIV transmission and delineate the utility of rhTRIM5α in anti-HIV therapy.

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