Erratum for Trinité et al., HIV-1 Vpr- and Reverse Transcription-Induced Apoptosis in Resting Peripheral Blood CD4 T Cells and Protection by Common Gamma-Chain Cytokines

ABSTRACTHIV-1 infection leads to the progressive depletion of the CD4 T cell compartment by various known and unknown mechanisms.In vivo, HIV-1 infects both activated and resting CD4 T cells, butin vitro, in the absence of any stimuli, resting CD4 T cells from peripheral blood are resistant to infection. This resistance is generally attributed to an intracellular environment that does not efficiently support processes such as reverse transcription (RT), resulting in abortive infection. Here, we show thatin vitroHIV-1 infection of resting CD4 T cells induces substantial cell death, leading to abortive infection.In vivo, however, various microenvironmental stimuli in lymphoid and mucosal tissues provide support for HIV-1 replication. For example, common gamma-chain cytokines (CGCC), such as interleukin-7 (IL-7), render resting CD4 T cells permissible to HIV-1 infection without inducing T cell activation. Here, we find that CGCC primarily allow productive infection by preventing HIV-1 triggering of apoptosis, as evidenced by early release of cytochromecand caspase 3/7 activation. Cell death is triggered both by products of reverse transcription and by virion-borne Vpr protein, and CGCC block both mechanisms. When HIV-1 RT efficiency was enhanced by SIVmac239 Vpx protein, cell death was still observed, indicating that the speed of reverse transcription and the efficiency of its completion contributed little to HIV-1-induced cell death in this system. These results show that a major restriction on HIV-1 infection in resting CD4 T cells resides in the capacity of these cells to survive the early steps of HIV-1 infection.IMPORTANCEA major consequence of HIV-1 infection is the destruction of CD4 T cells. Here, we show that delivery of virion-associated Vpr protein and the process of reverse transcription are each sufficient to trigger apoptosis of resting CD4 T cells isolated from peripheral blood. While these 2 mechanisms have been previously described in various cell types, we show for the first time their concerted effect in inducing resting CD4 T cell depletion. Importantly, we found that cytokines such as IL-7 and IL-4, which are particularly active in sites of HIV-1 replication, protect resting CD4 T cells from these cytopathic effects and, primarily through this protection, rather than through enhancement of specific replicative steps, they promote productive infection. This study provides important new insights for the understanding of the early steps of HIV-1 infection and T cell depletion.

Download Full-text

CD73+ CD127high Long-Term Memory CD4 T Cells Are Highly Proliferative in Response to Recall Antigens and Are Early Targets in HIV-1 Infection

International Journal of Molecular Sciences ◽

10.3390/ijms22020912 ◽

2021 ◽

Vol 22 (2) ◽

pp. 912

Author(s):

Nabila Seddiki ◽

John Zaunders ◽

Chan Phetsouphanh ◽

Vedran Brezar ◽

Yin Xu ◽

...

Keyword(s):

T Cells ◽

Peripheral Blood ◽

Cd4 T Cells ◽

Significant Proportion ◽

Long Term Memory ◽

Ki 67 ◽

Memory Cd4 T Cells ◽

Hiv 1

HIV-1 infection rapidly leads to a loss of the proliferative response of memory CD4+ T lymphocytes, when cultured with recall antigens. We report here that CD73 expression defines a subset of resting memory CD4+ T cells in peripheral blood, which highly express the α-chain of the IL-7 receptor (CD127), but not CD38 or Ki-67, yet are highly proliferative in response to mitogen and recall antigens, and to IL-7, in vitro. These cells also preferentially express CCR5 and produce IL-2. We reasoned that CD73+ memory CD4+ T cells decrease very early in HIV-1 infection. Indeed, CD73+ memory CD4+ T cells comprised a median of 7.5% (interquartile range: 4.5–10.4%) of CD4+ T cells in peripheral blood from healthy adults, but were decreased in primary HIV-1 infection to a median of 3.7% (IQR: 2.6–6.4%; p = 0.002); and in chronic HIV-1 infection to 1.9% (IQR: 1.1–3%; p < 0.0001), and were not restored by antiretroviral therapy. Moreover, we found that a significant proportion of CD73+ memory CD4+ T cells were skewed to a gut-homing phenotype, expressing integrins α4 and β7, CXCR3, CCR6, CD161 and CD26. Accordingly, 20% of CD4+ T cells present in gut biopsies were CD73+. In HIV+ subjects, purified CD73+ resting memory CD4+ T cells in PBMC were infected with HIV-1 DNA, determined by real-time PCR, to the same level as for purified CD73-negative CD4+ T cells, both in untreated and treated subjects. Therefore, the proliferative CD73+ subset of memory CD4+ T cells is disproportionately reduced in HIV-1 infection, but, unexpectedly, their IL-7 dependent long-term resting phenotype suggests that residual infected cells in this subset may contribute significantly to the very long-lived HIV proviral DNA reservoir in treated subjects.

Download Full-text

Primary HIV-1 Infection Is Associated with Preferential Depletion of CD4+ T Lymphocytes from Effector Sites in the Gastrointestinal Tract

Journal of Experimental Medicine ◽

10.1084/jem.20041196 ◽

2004 ◽

Vol 200 (6) ◽

pp. 761-770 ◽

Cited By ~ 776

Author(s):

Saurabh Mehandru ◽

Michael A. Poles ◽

Klara Tenner-Racz ◽

Amir Horowitz ◽

Arlene Hurley ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Peripheral Blood ◽

Highly Active Antiretroviral Therapy ◽

Cd4 T Cells ◽

Cell Loss ◽

Cd4 T Cell ◽

Suppressive Therapy ◽

Hiv 1 ◽

Gi Mucosa

Given its population of CCR5-expressing, immunologically activated CD4+ T cells, the gastrointestinal (GI) mucosa is uniquely susceptible to human immunodeficiency virus (HIV)-1 infection. We undertook this study to assess whether a preferential depletion of mucosal CD4+ T cells would be observed in HIV-1–infected subjects during the primary infection period, to examine the anatomic subcompartment from which these cells are depleted, and to examine whether suppressive highly active antiretroviral therapy could result in complete immune reconstitution in the mucosal compartment. Our results demonstrate that a significant and preferential depletion of mucosal CD4+ T cells compared with peripheral blood CD4+ T cells is seen during primary HIV-1 infection. CD4+ T cell loss predominated in the effector subcompartment of the GI mucosa, in distinction to the inductive compartment, where HIV-1 RNA was present. Cross-sectional analysis of a cohort of primary HIV-1 infection subjects showed that although chronic suppression of HIV-1 permits near-complete immune recovery of the peripheral blood CD4+ T cell population, a significantly greater CD4+ T cell loss remains in the GI mucosa, despite up to 5 yr of fully suppressive therapy. Given the importance of the mucosal compartment in HIV-1 pathogenesis, further study to elucidate the significance of the changes observed here is critical.

Download Full-text

CD4 T lymphocytes are primed to express Fas ligand by CD4 cross-linking and to contribute to CD8 T-cell apoptosis via Fas/FasL death signaling pathway

Blood ◽

10.1182/blood.v96.1.195.013k51_195_202 ◽

2000 ◽

Vol 96 (1) ◽

pp. 195-202 ◽

Cited By ~ 1

Author(s):

Masaki Tateyama ◽

Naoki Oyaizu ◽

Thomas W. McCloskey ◽

Soe Than ◽

Savita Pahwa

Keyword(s):

T Cells ◽

T Cell ◽

Cd8 T Cells ◽

Cd4 T Cells ◽

Interleukin 2 ◽

Cd8 T Cell ◽

T Cell Subsets ◽

Cross Linking ◽

Induced Apoptosis ◽

Hiv 1

CD4 molecules serve as coreceptors for the T-cell receptor (TCR)/CD3 complex that are engaged coordinately with TCR and facilitate antigen-specific T-cell activation leading to interleukin 2 (IL-2) production and proliferation. However, cross-ligation of CD4 molecules prior to TCR stimulation has been shown to prime CD4 T cells to undergo apoptosis. Although in vivo and in vitro experiments have implicated the involvement of Fas/FasL interaction in this CD4 cross-linking (CD4XL)-induced apoptosis, detailed mechanisms to account for cell death induction have not been elucidated. In the present study, we demonstrate that CD4XL in purified T cells not only led to Fas up-regulation but also primed CD4 T cells to express FasL upon CD3 stimulation and rendered the T cells susceptible to Fas-mediated apoptosis. Notably, in addition to CD4+ T cells, CD4XL-induced sensitization for apoptosis was observed in CD8+ T cells as well and was associated with Bcl-x down-modulation. Both CD4 and CD8 T-cell subsets underwent apoptosis following cell–cell contact with FasL+ CD4 T cells. CD28 costimulation abrogated CD4XL/CD3-induced apoptosis with restoration of IL-2 production and prevented Bcl-x down-modulation. As CD4 molecules are the primary receptors for human immunodeficiency virus 1 (HIV-1), we conclude that HIV-1 envelope mediated CD4XL can lead to the generation of FasL-expressing CD4+ T cells that can lead to apoptosis of CD4 as well as CD8 T cells. These findings implicate a novel mechanism for CD8 T-cell depletion in HIV disease.

Download Full-text

Peripheral T Follicular Helper Cells Are the Major HIV Reservoir within Central Memory CD4 T Cells in Peripheral Blood from Chronically HIV-Infected Individuals on Combination Antiretroviral Therapy

Journal of Virology ◽

10.1128/jvi.02883-15 ◽

2015 ◽

Vol 90 (6) ◽

pp. 2718-2728 ◽

Cited By ~ 69

Author(s):

Suresh Pallikkuth ◽

Mark Sharkey ◽

Dunja Z. Babic ◽

Sachin Gupta ◽

Geoffrey W. Stone ◽

...

Keyword(s):

T Cells ◽

Peripheral Blood ◽

Cd4 T Cells ◽

Central Memory ◽

T Cell Subsets ◽

Combination Antiretroviral Therapy ◽

Hiv Persistence ◽

Tfh Cells ◽

Follicular Helper ◽

Hiv 1

ABSTRACTIn this study, we examined the peripheral blood (PB) central memory (TCM) CD4+T cell subsets designated peripheral T follicular helper cells (pTfh cells) and non-pTfh cells to assess HIV permissiveness and persistence. Purified pTfh and non-pTfh cells from healthy HIV-negative donors were tested for HIV permissiveness using green fluorescent protein (GFP)-expressing HIV-1NL4-3/Ba-L, followed by viral reactivation using beads coated with anti-CD3/anti-CD28 monoclonal antibodies. The role of pTfh cells in HIV persistence was analyzed in 12 chronically HIV-1 infected patients before and 48 weeks after initiation of raltegravir-containing combination antiretroviral therapy (cART). Total cellular HIV-1 DNA and episomes containing two copies of the viral long terminal repeat (2LTR circles) were analyzed in using droplet digital PCR in the purified pTfh and non-pTfh cells. Activation-inducible HIV p24 expression was determined by flow cytometry. Results indicate that pTfh cells, in particular PD1+pTfh cells, showed greater permissiveness for HIV infection than non-pTfh cells. At week 48 on cART, HIV DNA levels were unchanged from pre-cART levels, although a significant decrease in 2LTR circles was observed in both cell subsets. Inducible HIV p24 expression was higher in pTfh cells than in non-pTfh cells, with the highest frequencies in the PD1+CXCR3−pTfh cell subset. Frequencies of HLADR+CD38+activated CD4 T cells correlated with 2LTR circles in pTfh and non-pTfh cells at both time points and with p24+cells at entry. In conclusion, among CD4 TCMcells in PB of aviremic patients on cART, pTfh cells, in particular the PD1+CXCR3−subset, constitute a major HIV reservoir that is sustained by ongoing residual immune activation. The inducible HIV p24 assay is useful for monitoring HIV reservoirs in defined CD4 T cell subsets.IMPORTANCEIdentification of the type and nature of the cellular compartments of circulating HIV reservoirs is important for targeting of HIV cure strategies. In lymph nodes (LN), a subset of CD4 T cells called T follicular helper (Tfh) cells are preferentially infected by HIV. Central memory (TCM) CD4 T cells are the major cellular reservoir for HIV in peripheral blood and contain a subset of CD4 TCMcells expressing chemokine receptor CXCR5 similar in function to LN Tfh cells termed peripheral Tfh (pTfh) cells. We found that the circulating pTfh cells are highly susceptible to HIV infection and that in HIV-infected patients, HIV persists in these cells following plasma virus suppression with potent cART. These pTfh cells, which constitute a subset of TCMCD4 T cells, can be readily monitored in peripheral blood to assess HIV persistence.

Download Full-text

IL-2 AND IFN-g, BUT NOT IL-4 SECRETION BY PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMC) ARE RELATED TO CD4+ T CELLS AND CLINICAL STATUS IN BRAZILIAN HIV-1-INFECTED SUBJECTS

Revista do Instituto de Medicina Tropical de São Paulo ◽

10.1590/s0036-46651998000600003 ◽

1998 ◽

Vol 40 (6) ◽

pp. 351-354 ◽

Cited By ~ 5

Author(s):

Marisa A. HONG ◽

Valéria L. WAKIM ◽

Simone J. SALOMÃO ◽

Luizete S. CAMARGO ◽

Jorge CASSEB ◽

...

Keyword(s):

T Cells ◽

Peripheral Blood Mononuclear Cells ◽

Peripheral Blood ◽

Cd4 T Cells ◽

Mononuclear Cells ◽

Clinical Status ◽

Peripheral Blood Mononuclear ◽

Blood Mononuclear Cells ◽

Hiv 1

Download Full-text

Immunofluorescence Detection of δ Opioid Receptors (DOR) on Human Peripheral Blood CD4+T Cells and DOR-Dependent Suppression of HIV-1 Expression

The Journal of Immunology ◽

10.4049/jimmunol.167.2.1097 ◽

2001 ◽

Vol 167 (2) ◽

pp. 1097-1102 ◽

Cited By ~ 31

Author(s):

Burt M. Sharp ◽

Kathy McAllen ◽

Genya Gekker ◽

Nahid A. Shahabi ◽

Phillip K. Peterson

Keyword(s):

T Cells ◽

Opioid Receptors ◽

Peripheral Blood ◽

Cd4 T Cells ◽

Human Peripheral Blood ◽

Hiv 1

Download Full-text

Relation of CD4+CD25+ Regulatory T Cells to Immune Status in Patients with HIV Infection.

Blood ◽

10.1182/blood.v104.11.3106.3106 ◽

2004 ◽

Vol 104 (11) ◽

pp. 3106-3106

Author(s):

Sachi Tsunemi ◽

Tsuyoshi Iwasaki ◽

Takehito Imado ◽

Satoshi Higasa ◽

Eizo Kakishita ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Immune Responses ◽

Hiv Infection ◽

Peripheral Blood ◽

Cd4 T Cells ◽

Cd4 T Cell ◽

Healthy Controls ◽

Cell Counts ◽

Hiv 1

Abstract Human immunodeficiency virus (HIV) infection is characterized by marked defects in CD4+ helper T cell (Th) functions that commonly progress to a substantial decline in peripheral CD4+ T cell counts. However, the mechanisms responsible for the loss of Th functions in HIV-infected patients independent of CD4+ T cell counts remains unclear. CD4+CD25+ regulatory T cells (T Reg) are essential for down-regulation of both autoreactive and alloreactive T cells. Therefore, we decided to investigate the role of T Reg in immune status of HIV-infected patients. We examined the expression of cell surface CD25, cytoplasmic IL-4 and cytoplasmic IFN-gamma in peripheral blood CD4+ T cells from both healthy controls (n=9) and HIV-infected patients (n=43). We also compared T Reg functions between the 2 groups. CD4+CD25+ T Reg isolated from both HIV-infected patients and healthy controls strongly expressed CD45RO, HLA-DR, and FoxP3, and suppressed the proliferation of CD4+CD25− T cells, suggesting that CD4+CD25+ T cells from both healthy controls and HIV-infected patients possess phenotypic and functional characteristics of Treg. CD4+CD25high T cells are a subset of circulating CD4+CD25+ T cells in normal humans and exhibit strong in vitro regulatory functions similar to those reported for murine CD4+CD25+ T Reg. We measured the frequency of CD4+CD25high T Reg by analysis of surface CD25 on CD4+ T cells in peripheral blood samples. We also examined Th1 and Th2 frequencies by analysis of cytoplasmic IFN-gamma and IL-4 levels in CD4+ T cells. T Reg from HIV-infected patients with detectable plasma HIV-1 RNA showed a statistically significant increase in CD4+CD25high cell frequency (p<0.05) compared to healthy controls, with T Reg frequencies inversely proportional to CD4+ T cell numbers (p<0.01). However, in HIV-infected patients with undetectable plasma HIV-RNA, frequencies of CD4+CD25high T Reg were not increased and not related to CD4+ T cell numbers. In both HIV-infected patient groups, T Reg frequency was inversely related to Th1 frequency (detectable: p<0.05, undetectable: p<0.001), but positively related to Th2 frequency (detectable: p<0.01, undetectable: p<0.001). Our results indicate that increased frequencies of peripheral blood T Reg were related to disease progression as measured by detectable plasma HIV-1 RNA, decreased peripheral blood CD4+ T cell counts, and polarization toward Th2 immune responses in HIV-infected patients. HIV infection may lead to induction of T reg that inhibit antiviral immune responses, resulting in the progression of the disease. Manipulation of T Reg could help restore antiviral immune responses in HIV infection, and prevent the progression of HIV infection.

Download Full-text