Multidirectional interactions are bridging human NK cells with plasmacytoid and monocyte-derived dendritic cells during innate immune responses

Blood ◽  
2006 ◽  
Vol 108 (12) ◽  
pp. 3851-3858 ◽  
Author(s):  
Mariella Della Chiesa ◽  
Chiara Romagnani ◽  
Andreas Thiel ◽  
Lorenzo Moretta ◽  
Alessandro Moretta

AbstractDuring innate immune responses, natural killer (NK) cells may interact with both plasmacytoid dendritic cells (pDCs) and monocyte-derived dendritic cells (MDDCs). We show that freshly isolated NK cells promote the release by pDCs of IFN-α, in a CpG-dependent manner, whereas they induce IL-6 production in a CpG-independent manner. In turn pDC-derived IFN-α up-regulates NK-mediated killing, whereas IL-6 could promote B-cell differentiation. We also show that exposure to exogenous IL-12 or coculture with maturing MDDCs up-regulates the NK-cell–dependent IFN-α production by pDCs. On the other hand, NK cells cocultured with pDCs acquire the ability to kill immature MDDCs, thus favoring their editing process. Finally, we show that activated NK cells are unable to lyse pDCs because these cells display an intrinsic resistance to lysis. The exposure of pDCs to IL-3 increased their susceptibility to NK-cell cytotoxicity resulting from a de novo expression of ligands for activating NK-cell receptors, such as the DNAM-1 ligand nectin-2. Thus, different cell-to-cell interactions and various cytokines appear to control a multidirectional network between NK cells, MDDCs, and pDCs that is likely to play an important role during the early phase of innate immune responses to viral infections and to tumors.

npj Vaccines ◽  
2020 ◽  
Vol 5 (1) ◽  
Author(s):  
David Pejoski ◽  
◽  
Casimir de Rham ◽  
Paola Martinez-Murillo ◽  
Francesco Santoro ◽  
...  

Abstract The rVSV-ZEBOV Ebolavirus vaccine confers protection within days after immunization, suggesting the contribution of innate immune responses. We report modulation of rVSV-ZEBOV vaccinee blood CD56+ NK cell numbers, NKG2D or NKp30 surface receptor expression, Killer Immunoglobulin-like Receptor (KIR)+ cell percentages and NK-cell-related genes on day 1 post immunization. Inverse correlations existed between the concentration of several plasma cytokines and inhibitory KIR+ CD56dim or cytokine-responsive CD56bright NK cells. Thus, NK cells may contribute to the early protective efficacy of rVSV-ZEBOV in humans.


2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Alicia Vázquez-Mendoza ◽  
Julio César Carrero ◽  
Miriam Rodriguez-Sosa

Antigen-presenting cells (APCs) sense the microenvironment through several types of receptors that recognize pathogen-associated molecular patterns. In particular, C-type lectins receptors (CLRs), which are expressed by distinct subsets of dendritic cells (DCs) and macrophages (MØs), recognize and internalize specific carbohydrate antigens in a Ca2+-dependent manner. The targeting of these receptors is becoming an efficient strategy for parasite recognition. However, relatively little is known about how CLRs are involved in both pathogen recognition and the internalization of parasites. The role of CLRs in parasite infections is an area of considerable interest because this research will impact our understanding of the initiation of innate immune responses, which influences the outcome of specific immune responses. This paper attempts to summarize our understanding of the effects of parasites’ interactions with CLRs.


2020 ◽  
Vol 2020 ◽  
pp. 1-9 ◽  
Author(s):  
Ji-Yoon Noh ◽  
Suk Ran Yoon ◽  
Tae-Don Kim ◽  
Inpyo Choi ◽  
Haiyoung Jung

Innate immunity represents the first barrier for host defense against microbial infection. Toll-like receptors (TLRs) are the most well-defined PRRs with respect to PAMP recognition and induction of innate immune responses. They recognize pathogen-associated molecular patterns (PAMPs) and trigger innate immune responses by inducing inflammatory cytokines, chemokines, antigen-presenting molecules, and costimulatory molecules. TLRs are expressed either on the cell surface or within endosomes of innate immune cells. NK cells are one of the innate immune cells and also express TLRs to recognize or respond to PAMPs. TLRs in NK cells induce the innate immune responses against bacterial and viral infections via inducing NK cytotoxicity and cytokine production. In this review, we will discuss the expression and cellular function of TLRs in NK cells and also introduce some therapeutic applications of TLR agonists for NK cell-mediated immunotherapy.


2007 ◽  
Vol 82 (6) ◽  
pp. 3021-3030 ◽  
Author(s):  
Kevin B. Walsh ◽  
Melissa B. Lodoen ◽  
Robert A. Edwards ◽  
Lewis L. Lanier ◽  
Thomas E. Lane

ABSTRACT Infection of SCID mice with a recombinant murine coronavirus (mouse hepatitis virus [MHV]) expressing the T-cell chemoattractant CXC chemokine ligand 10 (CXCL10) resulted in increased survival and reduced viral burden within the brain and liver compared to those of mice infected with an isogenic control virus (MHV), supporting an important role for CXCL10 in innate immune responses following viral infection. Enhanced protection in MHV-CXCL10-infected mice correlated with increased gamma interferon (IFN-γ) production by infiltrating natural killer (NK) cells within the brain and reduced liver pathology. To explore the underlying mechanisms associated with protection from disease in MHV-CXCL10-infected mice, the functional contributions of the NK cell-activating receptor NKG2D in host defense were examined. The administration of an NKG2D-blocking antibody to MHV-CXCL10-infected mice did not reduce survival, dampen IFN-γ production in the brain, or affect liver pathology. However, NKG2D neutralization increased viral titers within the liver, suggesting a protective role for NKG2D signaling in this organ. These data indicate that (i) CXCL10 enhances innate immune responses, resulting in protection from MHV-induced neurological and liver disease; (ii) elevated NK cell IFN-γ expression in the brain of MHV-CXCL10-infected mice occurs independently of NKG2D; and (iii) NKG2D signaling promotes antiviral activity within the livers of MHV-infected mice that is not dependent on IFN-γ and tumor necrosis factor alpha secretion.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Melanie R. Neeland ◽  
Samantha Bannister ◽  
Vanessa Clifford ◽  
Kate Dohle ◽  
Kim Mulholland ◽  
...  

AbstractChildren have mild severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) confirmed disease (COVID-19) compared to adults and the immunological mechanisms underlying this difference remain unclear. Here, we report acute and convalescent innate immune responses in 48 children and 70 adults infected with, or exposed to, SARS-CoV-2. We find clinically mild SARS-CoV-2 infection in children is characterised by reduced circulating subsets of monocytes (classical, intermediate, non-classical), dendritic cells and natural killer cells during the acute phase. In contrast, SARS-CoV-2-infected adults show reduced proportions of non-classical monocytes only. We also observe increased proportions of CD63+ activated neutrophils during the acute phase to SARS-CoV-2 in infected children. Children and adults exposed to SARS-CoV-2 but negative on PCR testing display increased proportions of low-density neutrophils that we observe up to 7 weeks post exposure. This study characterises the innate immune response during SARS-CoV-2 infection and household exposure in children.


2015 ◽  
Vol 96 (2) ◽  
pp. 294-310 ◽  
Author(s):  
Trina Das ◽  
Jean Jacques Hoarau ◽  
Marie Christine Jaffar Bandjee ◽  
Marianne Maquart ◽  
Philippe Gasque

2014 ◽  
Vol 82 (12) ◽  
pp. 5076-5085 ◽  
Author(s):  
Hua Ren ◽  
Yunfei Teng ◽  
Binghe Tan ◽  
Xiaoyu Zhang ◽  
Wei Jiang ◽  
...  

ABSTRACTExtracellular ATP (eATP), released as a “danger signal” by injured or stressed cells, plays an important role in the regulation of immune responses, but the relationship between ATP release and innate immune responses is still uncertain. In this study, we demonstrated that ATP was released through Toll-like receptor (TLR)-associated signaling in bothEscherichia coli-infected mice and lipopolysaccharide (LPS)- or Pam3CSK4-treated macrophages. This ATP release could be blocked completely only byN-ethylmaleimide (NEM), not by carbenoxolone (CBX), flufenamic acid (FFA), or probenecid, suggesting the key role of exocytosis in this process. Furthermore, LPS-induced ATP release could also be reduced dramatically through suppressing calcium mobilization by use of U73122, caffeine, and thapsigargin (TG). In addition, the secretion of interleukin-1β (IL-1β) and CCL-2 was enhanced significantly by ATP, in a time- and dose-dependent manner. Meanwhile, macrophage-mediated phagocytosis of bacteria was also promoted significantly by ATP stimulation. Furthermore, extracellular ATP reduced the number of invading bacteria and protected mice from peritonitis by activating purinergic receptors. Mechanistically, phosphorylation of AKT and ERK was overtly increased by ATP in antibacterial immune responses. Accordingly, if we blocked the P2X- and P2Y-associated signaling pathway by using suramin and pyridoxal phosphate-6-azo(benzene-2,4-disulfonic acid), tetrasodium salt (PPADS), the ATP-enhanced immune response was restrained significantly. Taken together, our findings reveal an internal relationship between danger signals and TLR signaling in innate immune responses, which suggests a potential therapeutic significance of calcium mobilization-mediated ATP release in infectious diseases.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Pamela Österlund ◽  
Miao Jiang ◽  
Veera Westenius ◽  
Suvi Kuivanen ◽  
Riia Järvi ◽  
...  

Abstract Zika virus (ZIKV) infections in humans are considered to be mild or subclinical. However, during the recent epidemics in the Pacific Islands and the Americas, the infection was associated with Quillain-Barré syndrome and congenital infections with fetal brain abnormalities, including microcephaly. Thus, more detailed understanding of ZIKV-host cell interactions and regulation of innate immune responses by strains of differential evolutionary origin is required. Here, we characterized the infection and immune responses triggered by two epidemic Asian/American lineage viruses, including an isolate from fetal brains, and a historical, low passage 1947 African lineage virus in human monocyte-derived dendritic cells (DCs) and macrophages. The epidemic Asian/American ZIKV replicated well and induced relatively good antiviral responses in human DCs whereas the African strain replicated less efficiently and induced weaker immune responses. In macrophages both the African and Asian strains showed limited replication and relatively weak cytokine gene expression. Interestingly, in macrophages we observed host protein degradation, especially IRF3 and STAT2, at early phases of infection with both lineage viruses, suggesting an early proteasomal activation in phagocytic cells. Our data indicates that ZIKV evolution has led to significant phenotypic differences in the replication characteristics leading to differential regulation of host innate immune responses.


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