Activation of NK Cells Induces CD4 Expression and Allows HIV−1 Infection.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 1253-1253
Author(s):  
Hideki Harada ◽  
Yumi Goto ◽  
Omar F. Dessouki ◽  
Shinya Suzu ◽  
Seiji Okada

Abstract Natural killer (NK) cells play critical roles in immune surveillance without deliberate prior sensitization and restriction by major histocompatibility complex (MHC). Although function and cell number of NK cells are influenced in AIDS patients, direct interaction between HIV and NK cells is still controversial. Because steady-state NK cells are negative for CD4 which is a key molecule for HIV infection. In this study, we established a condition inducing CD4 expression and HIV-1 infection of NK cells in vitro. CD4 was expressed on NK cells co-cultured with HFWT cells (NK cell-selective stimulating feeder cells) and IL-2. There were no differences in expression level of NK receptors, adhesion molecules and cytotoxicity between CD4+ and CD4- NK cell subpopulations. However, expression of activation markers, CD25 and HLA-DR, and size/granularity of the CD4+ NK cells were higher than CD4- NK cells. CD4+ NK cells expressed co-receptors for HIV-1, CCR5 and CXCR4. Thus, CD4 is induced on NK cells by activation, and the CD4+ NK cells are the possible target for HIV. Next, we exposed HIV-1 clone (JR-FL) to the HFWT-activated NK cells, however, direct HIV infection to the NK cells was not observed. While, co-culture of activated NK cells with HIV infected T cells allowed HIV infection of NK cells. Because NK cell-specific marker, NKp46, was detected on p24+CD3-CD56+ cells but not on CD3+ cells, p24+CD3-CD56+ cells were certainly NK cells. These results demonstrate that NK cells are the targets of HIV. Altogether, our data suggest that CD4+ T cells transfer HIV to NK cells during this cell-to-cell contact, which cause the NK cells to be the long-living viral reservoirs or modify the function of NK cells in HIV-infected patients. Our novel co-culture system using activated NK cells and HIV-infected T cells is the powerful tool to study the function of NK cells on HIV infection.

2005 ◽  
Vol 18 (2) ◽  
pp. 269-276 ◽  
Author(s):  
F. Martini ◽  
C. Agrati ◽  
G. D'Offizi ◽  
F. Poccia

Alterations in NK cell numbers and function have been repeatedly shown during HIV infection. In this study, NK cell number and MHC class I expression on CD4+ T cells were studied in HIV patients at different stages of disease progression. An increased expression of HLA-E was seen on CD4+ T cells. In parallel, a reduced number of CD94+ NK cells was observed in advanced disease stages. Moreover, a decline in CD94 expression on NK cells was observed at the HIV replication peak in patients undergoing antiretroviral treatment interruption, suggesting a role of viral replication on NK cells alterations. In vitro HIV infection induced a rapid down-regulation of HLA-A,B,C expression, paralleled by an increased expression of HLA-E surface molecules, the formal ligands of CD94 NK receptors. HIV-infected HLA-E expressing cells were able to inhibit NK cell cytotoxicity through HLA-E expression, since cytotoxicity was restored by antibody masking experiments. These data indicate that the CD94/HLA-E interaction may contribute to NK cell dysfunction in HIV infection, suggesting a role of HIV replication in this process.


2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
Ilona Hromadnikova ◽  
Petra Pirkova ◽  
Lucie Sedlackova

NK cells represent a potential tool for adoptive immunotherapy against tumors. Membrane-bound Hsp70 acts as a tumor-specific marker enhancing NK cell activity. Using flow cytometry the effect of in vitro stimulation with IL-2 or IL-15 alone or in combination with Hsp70-derived 14-mer peptide (TKD) on cell surface expression of NK activatory receptors (CD16, NKG2D, NKG2C, NKp46, NKp44, NKp30, KIR2DL4, DNAM-1, and LAMP1) and NK inhibitory receptors (NKG2A, KIR2DL2/L3, LIR1/ILT-2, and NKR-P1A) in healthy individuals was studied. Results were expressed as the percentage of receptor expressing cells and the amount of receptor expressed by CD3−CD56+cellular population. CD94, NKG2D, NKp44, NKp30, KIR2DL4, DNAM-1, LAMP1, NKG2A, and NKR-P1A were upregulated after the stimulation with IL-2 or IL-15 alone or in combination with TKD. KIR2DL2/L3 was upregulated only by IL-15 and IL-15/TKD. Concurrently, an increase in a number of NK cells positive for CD94, NKp44, NKp30, KIR2DL4, and LAMP1 was observed. IL-15 and IL-15/TKD caused also cell number rise positive for KIR2DL2/L3 and NKR-P1A. Cell number positive for NKG2C and NKG2A was increased only by IL-2 and IL-2/TKD. The diverse effect of IL-2 or IL-15 w or w/o TKD on cell surface expression was observed in CD16, NKp46, and LIR1/ILT-2.


2007 ◽  
Vol 204 (12) ◽  
pp. 3027-3036 ◽  
Author(s):  
Galit Alter ◽  
Maureen P. Martin ◽  
Nickolas Teigen ◽  
William H. Carr ◽  
Todd J. Suscovich ◽  
...  

Decline of peak viremia during acute HIV-1 infection occurs before the development of vigorous adaptive immunity, and the level of decline correlates inversely with the rate of AIDS progression, implicating a potential role for the innate immune response in determining disease outcome. The combined expression of an activating natural killer (NK) cell receptor, the killer immunoglobulin-like receptor (KIR) 3DS1, and its presumed ligand, human leukocyte antigen (HLA)–B Bw4-80I, has been associated in epidemiological studies with a slow progression to AIDS. We examined the functional ability of NK cells to differentially control HIV-1 replication in vitro based on their KIR and HLA types. NK cells expressing KIR3DS1 showed strong, significant dose- and cell contact–dependent inhibition of HIV-1 replication in target cells expressing HLA-B Bw4-80I compared with NK cells that did not express KIR3DS1. Furthermore, KIR3DS1+ NK cells and NKLs were preferentially activated, and lysed HIV-1 infected target cells in an HLA-B Bw4-80I–dependent manner. These data provide the first functional evidence that variation at the KIR locus influences the effectiveness of NK cell activity in the containment of viral replication.


Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 280-280
Author(s):  
Zhenya Ni ◽  
David A. Knorr ◽  
Christine L. Clouser ◽  
Peter Southern ◽  
Louis M. Mansky ◽  
...  

Abstract Abstract 280 Natural killer (NK) cells are known to be key components of the innate immune system with the ability to kill diverse tumor cells and virally infected cells. Our group has previously demonstrated derivation of CD45+CD56+ natural killer (NK) cells from human embryonic stem cells (hESCs)-derived hematopoietic CD34+CD45+ progenitor cells. These hESC-derived NK cells demonstrate potent killing of various tumor cells both in vitro and in vivo. More recently, we have also successfully generated NK cells from similar CD34+CD45+ hematopoietic progenitor cells derived from human induced pluripotent stem cells (iPSCs). Again, we find that these iPSC-derived NK cells also have effective anti-tumor activity in vitro. Notably, both the hESC and iPSC-derived NK cells are uniformly CD94+CD117−, corresponding to a more mature and cytotoxic NK cell population. This is in contrast to NK cells derived from umbilical cord blood (UCB) progenitor cells that produce a mixture of CD94+CD117− and CD94−CD117+ NK cells that are more heterogeneous in their cytotoxic activity. Previous studies of NK cells isolated from peripheral blood indicate they have activity against HIV-1-infected cells. Therefore, we hypothesized that both hESC and iPSC-derived NK cells would be able to kill HIV-1-infected targets. We have applied multiple complementary systems to test this hypothesis using both HIV-1-infected cell lines and HIV-1-infected primary T cells. First, we used a chronically infected cell line (H9/HTLV IIIB) to demonstrate specific cytolytic activity of hESC-derived NK cells. Here, we found CD107a expression (a marker of NK cell functional activity) was significantly upregulated on hESC-derived effectors stimulated by the HIV-1-infected targets compared to uninfected targets (13.7% vs. 4.3%). Next, we utilized primary human CD4 T cells infected with primary patient isolate HIV96-480 as targets to demonstrate the same effect to specifically activate both hESC and iPSC-derived NK cells. In both of these studies, control NK cell populations derived from human umbilical cord blood progenitor cells were significantly less active against HIV than the hESC and iPSC-derived NK cells. In addition to the cytolytic function against HIV-1-infected targets, we demonstrate hESC and iPSC-derived NK cells also suppress HIV-1 replication by producing CC-chemokines to competitively inhibit CCR5 co-receptor binding. CCL4 (MIP1b), a CCR5 ligand, is greatly induced in both hESC and iPSC-derived NK cells after incubation with HIV-1-infected targets compared to uninfected targets: 37.2% (HIV-infected) vs. 24.8% (uninfected) for hESC-NK cells and 32.5% (HIV-infected) vs. 21.6% (uninfected) for iPSC-NK cells. Lastly, we have also tested suppression of acute HIV-1 infection by hESC-derived NK cells in vitro. Here, the T-cell line CEM-GFP was infected with HIV-1 NL4-3 and cocultured with hESC-derived NK cells for two weeks. HIV-1-infected targets detected by flow cytometry for GFP expression were strongly decreased in comparison to controls in absence of NK cells (% of GFP+ cells: 0.74 vs. 26.4). In these analyses, expression of CD107a and CCL4 on the effectors again correlates with the inhibition of HIV-1 replication. Currently, as hESC and iPSC-derived NK cells express the Fc receptor CD16, we are using anti-envelope protein antibodies against HIV-1 infected primary human CD4 T cells to determine if antibody-dependent cellular cytotoxicity provides another mechanism of lytic activity for these novel NK cells. Collectively, our results demonstrate that NK cells derived from hESCs and iPSCs provide an effective novel cellular immunotherapy for HIV-1 infection. Disclosures: No relevant conflicts of interest to declare.


2008 ◽  
Vol 205 (13) ◽  
pp. 2965-2973 ◽  
Author(s):  
Susan Gilfillan ◽  
Christopher J. Chan ◽  
Marina Cella ◽  
Nicole M. Haynes ◽  
Aaron S. Rapaport ◽  
...  

Natural killer (NK) cells and CD8 T cells require adhesion molecules for migration, activation, expansion, differentiation, and effector functions. DNAX accessory molecule 1 (DNAM-1), an adhesion molecule belonging to the immunoglobulin superfamily, promotes many of these functions in vitro. However, because NK cells and CD8 T cells express multiple adhesion molecules, it is unclear whether DNAM-1 has a unique function or is effectively redundant in vivo. To address this question, we generated mice lacking DNAM-1 and evaluated DNAM-1–deficient CD8 T cell and NK cell function in vitro and in vivo. Our results demonstrate that CD8 T cells require DNAM-1 for co-stimulation when recognizing antigen presented by nonprofessional antigen-presenting cells; in contrast, DNAM-1 is dispensable when dendritic cells present the antigen. Similarly, NK cells require DNAM-1 for the elimination of tumor cells that are comparatively resistant to NK cell–mediated cytotoxicity caused by the paucity of other NK cell–activating ligands. We conclude that DNAM-1 serves to extend the range of target cells that can activate CD8 T cell and NK cells and, hence, may be essential for immunosurveillance against tumors and/or viruses that evade recognition by other activating or accessory molecules.


2018 ◽  
Vol 93 (3) ◽  
Author(s):  
Abena K. R. Kwaa ◽  
Chloe A. G. Talana ◽  
Joel N. Blankson

ABSTRACTCurrent shock-and-kill strategies for the eradication of the HIV-1 reservoir have resulted in blips of viremia but not in a decrease in the size of the latent reservoir in patients on suppressive antiretroviral therapy (ART). This discrepancy could potentially be explained by an inability of the immune system to kill HIV-1-infected cells following the reversal of latency. Furthermore, some studies have suggested that certain latency-reversing agents (LRAs) may inhibit CD8+T cell and natural killer (NK) cell responses. In this study, we tested the hypothesis that alpha interferon (IFN-α) could improve the function of NK cells from chronic progressors (CP) on ART. We show here that IFN-α treatment enhanced cytokine secretion, polyfunctionality, degranulation, and the cytotoxic potential of NK cells from healthy donors (HD) and CP. We also show that this cytokine enhanced the viral suppressive capacity of NK cells from HD and elite controllers or suppressors. Furthermore, IFN-α enhanced global CP CD8+T cell cytokine responses and the suppressive capacity of ES CD8+T cells. Our data suggest that IFN-α treatment may potentially be used as an immunomodulatory agent in HIV-1 cure strategies.IMPORTANCEData suggest that HIV+individuals unable to control infection fail to do so due to impaired cytokine production and/cytotoxic effector cell function. Consequently, the success of cure agendas such as the shock-and-kill strategy will probably depend on enhancing patient effector cell function. In this regard, NK cells are of particular interest since they complement the function of CD8+T cells. Here, we demonstrate the ability of short-course alpha interferon (IFN-α) treatments to effectively enhance such effector functions in chronic progressor NK cells without inhibiting their general CD8+T cell function. These results point to the possibility of exploring such short-course IFN-α treatments for the enhancement of effector cell function in HIV+patients in future cure strategies.


2019 ◽  
Vol 20 (18) ◽  
pp. 4490 ◽  
Author(s):  
Maria G. Desimio ◽  
Daniela A. Covino ◽  
Margherita Doria

Viral persistency in latently infected CD4+ T cells despite antiretroviral therapy (ART) represents a major drawback in the fight against HIV-1. Efforts to purge latent HIV-1 have been attempted using latency reversing agents (LRAs) that activate expression of the quiescent virus. However, initial trials have shown that immune responses of ART-treated patients are ineffective at clearing LRA-reactivated HIV-1 reservoirs, suggesting that an adjuvant immunotherapy is needed. Here we overview multiple lines of evidence indicating that natural killer (NK) cells have the potential to induce anti-HIV-1 responses relevant for virus eradication. In particular, we focus on the role of the NKG2D activating receptor that crucially enables NK cell-mediated killing of HIV-1-infected cells. We describe recent data indicating that LRAs can synergize with HIV-1 at upregulating ligands for NKG2D (NKG2DLs), hence sensitizing T cells that exit from viral latency for recognition and lysis by NK cells; in addition, we report in vivo and ex vivo data showing the potential benefits and drawbacks that LRAs may have on NKG2D expression and, more in general, on the cytotoxicity of NK cells. Finally, we discuss how the NKG2D/NKG2DLs axis can be exploited for the development of effective HIV-1 eradication strategies combining LRA-induced virus reactivation with recently optimized NK cell-based immunotherapies.


2014 ◽  
Vol 89 (1) ◽  
pp. 97-109 ◽  
Author(s):  
Shayarana L. Gooneratne ◽  
Jonathan Richard ◽  
Wen Shi Lee ◽  
Andrés Finzi ◽  
Stephen J. Kent ◽  
...  

ABSTRACTMany attempts to design prophylactic human immunodeficiency virus type 1 (HIV-1) vaccines have focused on the induction of neutralizing antibodies (Abs) that block infection by free virions. Despite the focus on viral particles, virus-infected cells, which can be found within mucosal secretions, are more infectious than free virus bothin vitroandin vivo. Furthermore, assessment of human transmission couples suggests infected seminal lymphocytes might be responsible for a proportion of HIV-1 transmissions. Although vaccines that induce neutralizing Abs are sought, only some broadly neutralizing Abs efficiently block cell-to-cell transmission of HIV-1. As HIV-1 vaccines need to elicit immune responses capable of controlling both free and cell-associated virus, we evaluated the potential of natural killer (NK) cells to respond in an Ab-dependent manner to allogeneic T cells bearing HIV-1 antigens. This study presents data measuring Ab-dependent anti-HIV-1 NK cell responses to primary and transformed allogeneic T-cell targets. We found that NK cells are robustly activated in an anti-HIV-1 Ab-dependent manner against allogeneic targets and that tested target cells are subject to Ab-dependent cytolysis. Furthermore, the educated KIR3DL1+NK cell subset from HLA-Bw4+individuals exhibits an activation advantage over the KIR3DL1−subset that contains both NK cells educated through other receptor/ligand combinations and uneducated NK cells. These results are intriguing and important for understanding the regulation of Ab-dependent NK cell responses and are potentially valuable for designing Ab-dependent therapies and/or vaccines.IMPORTANCENK cell-mediated anti-HIV-1 antibody-dependent functions have been associated with protection from infection and disease progression; however, their role in protecting from infection with allogeneic cells infected with HIV-1 is unknown. We found that HIV-1-specific ADCC antibodies bound to allogeneic cells infected with HIV-1 or coated with HIV-1 gp120 were capable of activating NK cells and/or trigging cytolysis of the allogeneic target cells. This suggests ADCC may be able to assist in preventing infection with cell-associated HIV-1. In order to fully utilize NK cell-mediated Ab-dependent effector functions, it might also be important that educated NK cells, which hold the highest activation potential, can become activated against targets bearing HIV-1 antigens and expressing the ligands for self-inhibitory receptors. Here, we show that with Ab-dependent stimulation, NK cells expressing inhibitory receptors can mediate robust activation against targets expressing the ligands for those receptors.


2010 ◽  
Vol 207 (13) ◽  
pp. 2869-2881 ◽  
Author(s):  
Christof Geldmacher ◽  
Njabulo Ngwenyama ◽  
Alexandra Schuetz ◽  
Constantinos Petrovas ◽  
Klaus Reither ◽  
...  

HIV-1 infection results in the progressive loss of CD4 T cells. In this study, we address how different pathogen-specific CD4 T cells are affected by HIV infection and the cellular parameters involved. We found striking differences in the depletion rates between CD4 T cells to two common opportunistic pathogens, cytomegalovirus (CMV) and Mycobacterium tuberculosis (MTB). CMV-specific CD4 T cells persisted after HIV infection, whereas MTB-specific CD4 T cells were depleted rapidly. CMV-specific CD4 T cells expressed a mature phenotype and produced very little IL-2, but large amounts of MIP-1β. In contrast, MTB-specific CD4 T cells were less mature, and most produced IL-2 but not MIP-1β. Staphylococcal enterotoxin B–stimulated IL-2–producing cells were more susceptible to HIV infection in vitro than MIP-1β–producing cells. Moreover, IL-2 production was associated with expression of CD25, and neutralization of IL-2 completely abrogated productive HIV infection in vitro. HIV DNA was found to be most abundant in IL-2–producing cells, and least abundant in MIP-1β–producing MTB-specific CD4 T cells from HIV-infected subjects with active tuberculosis. These data support the hypothesis that differences in function affect the susceptibility of pathogen-specific CD4 T cells to HIV infection and depletion in vivo, providing a potential mechanism to explain the rapid loss of MTB-specific CD4 T cells after HIV infection.


2019 ◽  
Vol 220 (12) ◽  
pp. 1892-1903 ◽  
Author(s):  
Xi Chen ◽  
Huihui Chen ◽  
Zining Zhang ◽  
Yajing Fu ◽  
Xiaoxu Han ◽  
...  

Abstract Background Natural killer (NK) cells are an important type of effector cell in the innate immune response, and also have a role in regulation of the adaptive immune response. Several studies have indicated that NK cells may influence CD4+ T cells during HIV infection. Methods In total, 51 HIV-infected individuals and 15 healthy controls participated in this study. We performed the flow cytometry assays and real-time PCR for the phenotypic analysis and the functional assays of NK cell-mediated deletion of CD4+ T cells, phosphorylation of nuclear factor-κB (NF-κB/p65) and the intervention of metformin. Results Here we detected high CD54 expression on CD4+ T cells in HIV-infected individuals, and demonstrate that upregulated CD54 is associated with disease progression in individuals infected with HIV. We also show that CD54 expression leads to the deletion of CD4+ T cells by NK cells in vitro, and that this is modulated by NF-κB/p65 signaling. Further, we demonstrate that metformin can suppress CD54 expression on CD4+ T cells by inhibiting NF-κB/p65 phosphorylation. Conclusions Our data suggest that further studies to evaluate the potential role of metformin as adjunctive therapy to reconstitute immune function in HIV-infected individuals are warranted.


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