scholarly journals Th2-like CD8+ T cells showing B cell helper function and reduced cytolytic activity in human immunodeficiency virus type 1 infection.

1994 ◽  
Vol 180 (2) ◽  
pp. 489-495 ◽  
Author(s):  
E Maggi ◽  
M G Giudizi ◽  
R Biagiotti ◽  
F Annunziato ◽  
R Manetti ◽  
...  

We analyzed at clonal level the functional profile of circulating or skin-infiltrating T lymphocytes from two individuals infected with the human immunodeficiency virus type 1 (HIV-1), suffering from a Job's-like syndrome (eczematous dermatitis, recurrent skin and sinopulmonary infections, and hypergammaglobulinemia E) and showing virtually no circulating CD4+ T cells. Most of the CD3+ T cell clones generated from both patients were CD4- CD8+ TCR alpha beta +. The others were CD4- CD8- TCR alpha beta + which exhibited reduced mRNA expression for the CD8 molecule or no mRNA expression for either CD4 or CD8 molecules. The great majority of both CD4- CD8+ and CD4- CD8- did not produce interferon (IFN) gamma and exhibited reduced cytolytic activity. Rather, most of them produced large amounts of both interleukin (IL) 4 and IL-5 and provided B cell helper function for IgE synthesis. These data suggest that a switch of cytolytic CD8+ T cells showing a Th1-like cytokine secretion profile to cells that make Th2-type cytokines, exhibit reduced cytolytic potential, and provide B cell helper function can occur in the course of HIV-1 infection. These cells may contribute to the reduced defense against viral infections and intracellular parasites and account for the elevated IgE serum levels, eosinophilia, and the allergic-like clinical manifestations seen in a proportion of HIV-1-infected individuals.

2002 ◽  
Vol 76 (15) ◽  
pp. 7535-7543 ◽  
Author(s):  
Hiroko Tomiyama ◽  
Hirofumi Akari ◽  
Akio Adachi ◽  
Masafumi Takiguchi

ABSTRACT A previous study using a Nef-defective human immunodeficiency virus type 1 (HIV-1) mutant suggested that Nef-mediated down-regulation of HLA class I on the infected cell surface affects the cytolytic activity of HIV-1-specific cytotoxic T-lymphocyte (CTL) clones for HIV-1-infected primary CD4+ T cells. We confirmed this effect by using a nef-mutant HIV-1 strain (NL-M20A) that expresses a Nef protein which does not induce down-regulation of HLA class I molecules but is otherwise functional. HIV-1-specific CTL clones were not able to kill primary CD4+ T cells infected with a Nef-positive HIV-1 strain (NL-432) but efficiently lysed CD4+ T cells infected with NL-M20A. Interestingly, CTL clones stimulated with NL-432-infected CD4+ T cells were able to produce cytokines, albeit at a lower level than when stimulated with NL-M20A-infected CD4+ T cells. This indicates that Nef-mediated HLA class I down-regulation affects CTL cytokine production to a lesser extent than cytolytic activity. Replication of NL-432 was partially suppressed in a coculture of HIV-1-infected CD4+ T cells and HIV-1-specific CTL clones, while replication of NL-M20A was completely suppressed. These results suggest that HIV-1-specific CD8+ T cells are able to partially suppress the replication of HIV-1 through production of soluble HIV-1-suppressive factors such as chemokines and gamma interferon. These findings may account for the mechanism whereby HIV-1-specific CD8+ T cells are able to partially but not completely control HIV-1 replication in vivo.


2007 ◽  
Vol 81 (7) ◽  
pp. 3477-3486 ◽  
Author(s):  
Martin D. Hyrcza ◽  
Colin Kovacs ◽  
Mona Loutfy ◽  
Roberta Halpenny ◽  
Lawrence Heisler ◽  
...  

ABSTRACT Changes in T-cell function are a hallmark of human immunodeficiency virus type 1 (HIV-1) infection, but the pathogenic mechanisms leading to these changes are unclear. We examined the gene expression profiles in ex vivo human CD4+ and CD8+ T cells from untreated HIV-1-infected individuals at different clinical stages and rates of disease progression. Profiles of pure CD4+ and CD8+ T-cell subsets from HIV-1-infected nonprogressors with controlled viremia were indistinguishable from those of individuals not infected with HIV-1. Similarly, no gene clusters could distinguish T cells from individuals with early infection from those seen in chronic progressive HIV-1 infection, whereas differences were observed between uninfected individuals or nonprogressors versus early or chronic progressors. In early and chronic HIV-1 infection, three characteristic gene expression signatures were observed. (i) CD4+ and CD8+ T cells showed increased expression of interferon-stimulated genes (ISGs). However, some ISGs, including CXCL9, CXCL10, and CXCL11, and the interleukin-15 alpha receptor were not upregulated. (ii) CD4+ and CD8+ T cells showed a cluster similar to that observed in thymocytes. (iii) More genes were differentially regulated in CD8+ T cells than in CD4+ T cells, including a cluster of genes downregulated exclusively in CD8+ T cells. In conclusion, HIV-1 infection induces a persistent T-cell transcriptional profile, early in infection, characterized by a dramatic but potentially aberrant interferon response and a profile suggesting an active thymic output. These findings highlight the complexity of the host-virus relationship in HIV-1 infection.


2002 ◽  
Vol 76 (17) ◽  
pp. 8855-8863 ◽  
Author(s):  
Angela Malaspina ◽  
Susan Moir ◽  
David C. Nickle ◽  
Eileen T. Donoghue ◽  
Kisani M. Ogwaro ◽  
...  

ABSTRACT Human immunodeficiency virus type 1 (HIV-1) virions bind to B cells in the peripheral blood and lymph nodes through interactions between CD21 on B cells and complement-complexed virions. B-cell-bound virions have been shown to be highly infectious, suggesting a unique mode of HIV-1 dissemination by B cells circulating between peripheral blood and lymphoid tissues. In order to investigate the relationship between B-cell-bound HIV-1 and viruses found in CD4+ T cells and in plasma, we examined the genetic relationships of HIV-1 found in the blood and lymph nodes of chronically infected patients with heteroduplex mobility and tracking assays and DNA sequence analysis. In samples from 13 of 15 patients examined, HIV-1 variants in peripheral blood-derived B cells were closely related to virus in CD4+ T cells and more divergent from virus in plasma. In samples from five chronically viremic patients for whom analyses were extended to include lymph node-derived HIV-1 isolates, B-cell-associated HIV-1 and CD4+-T-cell-associated HIV-1 in the lymph nodes were equivalent in their divergence from virus in peripheral blood-derived B cells and generally more distantly related to virus in peripheral blood-derived CD4+ T cells. These results indicates virologic cross talk between B cells and CD4+ T cells within the microenvironment of lymphoid tissues and, to a lesser extent, between cells in lymph nodes and the peripheral blood. These findings also indicate that most of the virus in plasma originates from cells other than CD4+ T cells in the peripheral blood and lymph nodes.


2002 ◽  
Vol 46 (4) ◽  
pp. 982-990 ◽  
Author(s):  
Jan Münch ◽  
Ludger Ständker ◽  
Stefan Pöhlmann ◽  
Frédéric Baribaud ◽  
Armin Papkalla ◽  
...  

ABSTRACT Proteolytic processing of the abundant plasmatic human CC chemokine 1 (HCC-1) generates a truncated form, HCC-1[9-74], which is a potent agonist of CCR1, CCR3, and CCR5; promotes calcium influx and chemotaxis of T lymphoblasts, monocytes, and eosinophils; and inhibits infection by CCR5-tropic human immunodeficiency virus type 1 (HIV-1) isolates. In the present study we demonstrate that HCC-1[9-74] interacts with the second external loop of CCR5 and inhibits replication of CCR5-tropic HIV-1 strains in both primary T cells and monocyte-derived macrophages. Low concentrations of the chemokine, however, frequently enhanced the replication of CCR5-tropic HIV-1 isolates but not the replication of X4-tropic HIV-1 isolates. Only HCC-1[9-74] and HCC-1[10-74], but not other HCC-1 length variants, displayed potent anti-HIV-1 activities. Fluorescence-activated cell sorter analysis revealed that HCC-1[9-74] caused up to 75% down-regulation of CCR5 cell surface expression, whereas RANTES (regulated on activation, normal T-cell expressed and secreted) achieved a reduction of only about 40%. Studies performed with green fluorescent protein-tagged CCR5 confirmed that both HCC-1[9-74] and RANTES, but not full-length HCC-1, mediated specific internalization of the CCR5 HIV-1 entry cofactor. Our results demonstrate that the interaction with HCC-1[9-74] causes effective intracellular sequestration of CCR5, but they also indicate that the effect of HCC-1[9-74] on viral replication is subject to marked cell donor- and HIV-1 isolate-dependent variations.


2005 ◽  
Vol 79 (15) ◽  
pp. 10053-10058 ◽  
Author(s):  
Angélique B. van ′t Wout ◽  
J. Victor Swain ◽  
Michael Schindler ◽  
Ushnal Rao ◽  
Melissa S. Pathmajeyan ◽  
...  

ABSTRACT Several recent reports indicate that cholesterol might play an important role in human immunodeficiency virus type 1 (HIV-1) replication. We investigated the effects of HIV-1 infection on cholesterol biosynthesis and uptake using microarrays. HIV-1 increased gene expression of cholesterol genes in both transformed T-cell lines and primary CD4+ T cells. Consistent with our microarray data, 14C-labeled mevalonate and acetate incorporation was increased in HIV-1-infected cells. Our data also demonstrate that changes in cholesterol biosynthesis and uptake are only observed in the presence of functional Nef, suggesting that increased cholesterol synthesis may contribute to Nef-mediated enhancement of virion infectivity and viral replication.


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.


2002 ◽  
Vol 76 (15) ◽  
pp. 7812-7821 ◽  
Author(s):  
Rogier W. Sanders ◽  
Esther C. de Jong ◽  
Christopher E. Baldwin ◽  
Joost H. N. Schuitemaker ◽  
Martien L. Kapsenberg ◽  
...  

ABSTRACT Dendritic cells (DC) support human immunodeficiency virus type 1 (HIV-1) transmission by capture of the virus particle in the mucosa and subsequent transport to the draining lymph node, where HIV-1 is presented to CD4+ Th cells. Virus transmission involves a high-affinity interaction between the DC-specific surface molecule DC-SIGN and the viral envelope glycoprotein gp120 and subsequent internalization of the virus, which remains infectious. The mechanism of viral transmission from DC to T cells is currently unknown. Sentinel immature DC (iDC) develop into Th1-promoting effector DC1 or Th2-promoting DC2, depending on the activation signals. We studied the ability of these effector DC subsets to support HIV-1 transmission in vitro. Compared with iDC, virus transmission is greatly upregulated for the DC1 subset, whereas DC2 cells are inactive. Increased transmission by DC1 correlates with increased expression of ICAM-1, and blocking studies confirm that ICAM-1 expression on DC is important for HIV transmission. The ICAM-1-LFA-1 interaction is known to be important for immunological cross talk between DC and T cells, and our results indicate that this cell-cell contact is exploited by HIV-1 for efficient transmission.


2007 ◽  
Vol 81 (11) ◽  
pp. 5547-5560 ◽  
Author(s):  
Clare Jolly ◽  
Ivonne Mitar ◽  
Quentin J. Sattentau

ABSTRACT Human immunodeficiency virus type 1 (HIV-1) infection of CD4+ T cells leads to the production of new virions that assemble at the plasma membrane. Gag and Env accumulate in the context of lipid rafts at the inner and outer leaflets of the plasma membrane, respectively, forming polarized domains from which HIV-1 buds. HIV-1 budding can result in either release of cell-free virions or direct cell-cell spread via a virological synapse (VS). The recruitment of Gag and Env to these plasma membrane caps in T cells is poorly understood but may require elements of the T-cell secretory apparatus coordinated by the cytoskeleton. Using fixed-cell immunofluorescence labeling and confocal microscopy, we observed a high percentage of HIV-1-infected T cells with polarized Env and Gag in capped, lipid raft-like assembly domains. Treatment of infected T cells with inhibitors of actin or tubulin remodeling disrupted Gag and Env compartmentalization within the polarized raft-like domains. Depolymerization of the actin cytoskeleton reduced Gag release and viral infectivity, and actin and tubulin inhibitors reduced Env incorporation into virions. Live- and fixed-cell confocal imaging and assay of de novo DNA synthesis by real-time PCR allowed quantification of HIV-1 cell-cell transfer. Inhibition of actin and tubulin remodeling in infected cells interfered with cell-cell spread across a VS and reduced new viral DNA synthesis. Based on these data, we propose that HIV-1 requires both actin and tubulin components of the T-cell cytoskeleton to direct its assembly and budding and to elaborate a functional VS.


2009 ◽  
Vol 16 (7) ◽  
pp. 1060-1065 ◽  
Author(s):  
Odd Odinsen ◽  
David Parker ◽  
Frans Radebe ◽  
Mikey Guness ◽  
David A Lewis

ABSTRACT Diagnosis of acute human immunodeficiency virus (HIV) infection, a key driver of the HIV epidemic, remains a public health challenge. The PlasmAcute technology offers an opportunity to detect early anti-HIV antibody responses. B lymphocytes (B cells) were isolated from the blood of seronegative miners in South Africa by using the PlasmAcute method. B-cell lysates and paired sera were tested for anti-HIV-1 antibodies by two different enzyme-linked immunosorbent assays; immunoreactivity was confirmed by Western blotting. All volunteers were tested for HIV type 1 (HIV-1) viral load, p24 antigen, and CD4 count. Sera from HIV-seronegative men who had positive viral loads and were positive for p24 antigen were retested for anti-HIV antibodies after immune complex dissociation. Anti-HIV antibodies were detected in lysates from 16/259 subjects without immunoreactivity in paired sera. Four subjects, one of whom had a positive viral load initially, subsequently seroconverted. Six subjects showed transient anti-HIV-1 antibodies in the lysates and tested negative for all markers at the follow-up. Five subjects without follow-up data initially had lysate-positive/serum-negative samples, and these cases were classified as inconclusive. One subject had lysate antibodies and a detectable viral load but was seronegative at follow-up. In conclusion, lysate-derived anti-HIV-1 B-cell antibodies can be detected prior to seroconversion and earlier than or contemporary with HIV-1 RNA detection.


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