Showing papers by "Lewis L. Lanier published in 2013"

Identification of transcriptional regulators in the mouse immune system

Abstract: The differentiation of hematopoietic stem cells into cells of the immune system has been studied extensively in mammals, but the transcriptional circuitry that controls it is still only partially understood. Here, the Immunological Genome Project gene-expression profiles across mouse immune lineages allowed us to systematically analyze these circuits. To analyze this data set we developed Ontogenet, an algorithm for reconstructing lineage-specific regulation from gene-expression profiles across lineages. Using Ontogenet, we found differentiation stage–specific regulators of mouse hematopoiesis and identified many known hematopoietic regulators and 175 previously unknown candidate regulators, as well as their target genes and the cell types in which they act. Among the previously unknown regulators, we emphasize the role of ETV5 in the differentiation of γδ T cells. As the transcriptional programs of human and mouse cells are highly conserved, it is likely that many lessons learned from the mouse model apply to humans.

Respiratory virus-induced EGFR activation suppresses IRF1-dependent interferon λ and antiviral defense in airway epithelium.

Abstract: Viruses suppress host responses to increase infection, and understanding these mechanisms has provided insights into cellular signaling and led to novel therapies. Many viruses (e.g., Influenza virus, Rhinovirus [RV], Cytomegalovirus, Epstein-Barr virus, and Hepatitis C virus) activate epithelial epidermal growth factor receptor (EGFR), a tyrosine kinase receptor, but the role of EGFR in viral pathogenesis is not clear. Interferon (IFN) signaling is a critical innate antiviral host response and recent experiments have implicated IFN-λ, a type III IFN, as the most significant IFN for mucosal antiviral immune responses. Despite the importance of IFN-λ in epithelial antiviral responses, the role and mechanisms of epithelial IFN-λ signaling have not been fully elucidated. We report that respiratory virus-induced EGFR activation suppresses endogenous airway epithelial antiviral signaling. We found that Influenza virus– and RV-induced EGFR activation suppressed IFN regulatory factor (IRF) 1–induced IFN-λ production and increased viral infection. In addition, inhibition of EGFR during viral infection augmented IRF1 and IFN-λ, which resulted in decreased viral titers in vitro and in vivo. These findings describe a novel mechanism that viruses use to suppress endogenous antiviral defenses, and provide potential targets for future therapies.

Maternal decidual macrophages inhibit NK cell killing of invasive cytotrophoblasts during human pregnancy

Abstract: Human pregnancy is an immunological paradox. Semiallogeneic (fetal) placental cells (extravillous cytotrophoblasts [CTBs]) invade the uterine lining (decidua), which contains a unique decidual natural killer (dNK) cell population, identified by the cell surface phenotype CD56(bright) CD16(-) CD3(-) and CD14(+) CD206(+) macrophages (dMac). Previous reports suggested that human dNK cells are not a threat to the fetoplacental unit because they are anergic. In contrast, here we showed that purified and exogenously stimulated dNK cells are capable killers of cellular targets, including semiallogeneic CTBs. However, dMacs in the decidual leukocyte (DL) population restrained dNK killing through a transforming growth factor beta1 (TGF-beta1)-dependent mechanism. Our findings support a new model whereby dNK cells, capable of killing CTBs, are prevented from doing so by neighboring macrophages, thus protecting the fetal cells from NK cell attack. We speculate that this mechanism would inhibit dNK cell-mediated killing, even under conditions where high levels of cytokines may stimulate dNK cells, which could pose a threat to the developing placenta.

CD56negCD16+NK cells are activated mature NK cells with impaired effector function during HIV-1 infection

Abstract: A subset of CD3negCD56negCD16+ Natural Killer (NK) cells is highly expanded during chronic HIV-1 infection. The role of this subset in HIV-1 pathogenesis remains unclear. The lack of NK cell lineage-specific markers has complicated the study of minor NK cell subpopulations. Using CD7 as an additional NK cell marker, we found that CD3negCD56negCD16+ cells are a heterogeneous population comprised of CD7+ NK cells and CD7neg non-classical myeloid cells. CD7+CD56negCD16+ NK cells are significantly expanded in HIV-1 infection. CD7+CD56negCD16+ NK cells are mature and express KIRs, the C-type lectin-like receptors NKG2A and NKG2C, and natural cytotoxicity receptors similar to CD7+CD56+CD16+ NK cells. CD7+CD56neg NK cells in healthy donors produced minimal IFNγ following K562 target cell or IL-12 plus IL-18 stimulation; however, they degranulated in response to K562 stimulation similar to CD7+CD56+ NK cells. HIV-1 infection resulted in reduced IFNγ secretion following K562 or cytokine stimulation by both NK cell subsets compared to healthy donors. Decreased granzyme B and perforin expression and increased expression of CD107a in the absence of stimulation, particularly in HIV-1-infected subjects, suggest that CD7+CD56negCD16+ NK cells may have recently engaged target cells. Furthermore, CD7+CD56negCD16+ NK cells have significantly increased expression of CD95, a marker of NK cell activation. Taken together, CD7+CD56negCD16+ NK cells are activated, mature NK cells that may have recently engaged target cells.

Stage-specific regulation of natural killer cell homeostasis and response against viral infection by microRNA-155

Abstract: Natural killer (NK) cells function in the recognition and destruction of host cells infected with pathogens. Many regulatory mechanisms govern the potent responses of NK cells, both at the cellular and molecular level. Ablation of microRNA (miRNA) processing enzymes demonstrated that miRNAs play critical roles in NK cell differentiation and function; however, the role of individual miRNAs requires further investigation. Using mice containing a targeted deletion of microRNA-155 (miR-155), we observed defects in NK cell maintenance and maturation at steady state, as well as in homeostatic proliferation in lymphopenic mice. In addition, we discovered that miR-155 is up-regulated in activated NK cells during mouse cytomegalovirus (MCMV) infection in response to signals from the proinflammatory cytokines IL-12 and IL-18 and through signal transducer and activator of transcription 4 (STAT4) signaling. Although miR-155 was found to be dispensable for cytotoxicity and cytokine production when triggered through activating receptors, NK cells lacking miR-155 exhibited severely impaired effector and memory cell numbers in both lymphoid and nonlymphoid tissues after MCMV infection. We demonstrate that miR-155 differentially targets Noxa and suppressor of cytokine signaling 1 (SOCS1) in NK cells at distinct stages of homeostasis and activation. NK cells constitutively expressing Noxa and SOCS1 exhibit profound defects in expansion during the response to MCMV infection, suggesting that their regulation by miR-155 promotes antiviral immunity.

Shades of grey — the blurring view of innate and adaptive immunity

Abstract: This special issue of Nature Reviews Immunology focuses on the types of lymphocyte that blur the traditional boundaries between the innate and adaptive immune systems. The development and functional properties of 'innate-like' B and T cells and natural killer (NK) cells are reviewed and the emerging understanding of newly discovered innate lymphoid cells (ILCs) is considered.

MicroRNA function in NK-cell biology.

Abstract: The important role of microRNAs in directing immune responses has become increasingly clear. Here, we highlight discoveries uncovering the role of specific microRNAs in regulating the development and function of natural killer (NK) cells. Furthermore, we discuss the impact of NK cells on the entire immune system during global and specific microRNA ablation in the settings of inflammation, infection, and immune dysregulation.

Transport of misfolded endoplasmic reticulum proteins to the cell surface by MHC class II molecules

Abstract: Nascent MHC class II molecules are associated with the invariant chain and are transported to the endolysosomal pathway, where MHC class II molecules acquire peptide antigens. On the other hand, misfolded endoplasmic reticulum (ER) proteins are generally degraded in the cells and are neither expressed on the cell surface nor secreted. Here, we found that MHC class II molecules associate with some misfolded ER proteins via the peptide-binding groove in competition with invariant chain. The misfolded proteins associated with MHC class II molecules are transported intact to the cell surface without processing to peptides. Furthermore, these complexes efficiently stimulate antigen-specific B cells. These findings reveal that MHC class II molecules function as a chaperone for the cell surface expression of misfolded ER proteins. In addition, we suggest that MHC class II molecules present not only peptides but also intact host-cell-derived proteins on the cell surface. These findings provide new insights into the function of MHC class II molecules.

CEACAM1 on activated NK cells inhibits NKG2D‐mediated cytolytic function and signaling

Abstract: Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) is expressed on activated natural killer (NK) cells wherein it inhibits lysis of CEACAM1-bearing tumor cell lines. The mechanism for this is unknown. Here, we show that interleukin-2-induced expression of CEACAM1 on both mouse and primary human NK cells impairs the ability of NK gene complex group 2 member D (NKG2D) to stimulate cytolysis of CEACAM1-bearing cells. This process requires the expression of CEACAM1 on the NK cells and on the tumor cells, which is consistent with the involvement of trans-homophilic interactions between CEACAM1. Mechanistically, co-engagement of NKG2D and CEACAM1 results in a biochemical association between these two surface receptors and the recruitment of Src homology phosphatase 1 by CEACAM1 that leads to dephosphorylation of the guanine nucleotide exchange factor Vav1 and blockade of downstream signaling that is associated with the initiation of cytolysis. Thus, CEACAM1 on activated NK cells functions as an inhibitory receptor for NKG2D-mediated cytolysis, which has important implications for understanding the means by which CEACAM1 expression adversely affects tumor immunity.

Skewed Distribution of Natural Killer Cells in Psoriasis Skin Lesions

Abstract: Psoriasis is a hyper-proliferative disease of the skin in which immunological mechanisms play a direct pathogenetic role. There have been limited studies of natural killer (NK) cells in psoriasis. The aim of this study was to examine the phenotype of NK cells in skin biopsies and peripheral blood mononuclear cells from patients with psoriasis and healthy controls. CD56(+) CD16(-) and CD56(+) CD16(+) NK cells were isolated from lesional skin, unaffected skin and PBMC of psoriasis patients, and normal skin and PBMC from healthy controls. The expression of CD57, NKG2A and NKG2C was assessed by flow cytometry. NK cells in psoriasis skin lesions were skewed in their expression of CD57, a marker of NK cell maturity, with CD57 expression significantly reduced and NKG2A expression increased on NK cells in lesional and unaffected skin compared to controls. These data suggest that in this patient cohort, NK cells could be isolated from psoriasis lesions and exhibit an immature phenotype.

Founding father of FACS: Professor Leonard A. Herzenberg (1931–2013)

Abstract: The stunning ability to collect quantitative single-cell analyses of up to 20 parameters simultaneously (1), at rates of tens of thousands of cells per second, and then to divert and recover a specific single live cell, or a subpopulation of live cells, with desired characteristics is the genius of fluorescence-activated cell sorting (FACS). FACS applied in conjunction with fluorescently labeled monoclonal antibodies (Mabs) derived from immortalized hybridoma cell lines is a ubiquitous core technology in medicine and biomedical research, impacting all of immunology, cancer diagnosis, stem cell identification and transplantation, AIDS monitoring, and a variety of therapies, as well as plant and microbial biology. It is, in fact, very difficult to imagine the biomedical research landscape of the last 40 years without FACS. Len and Lee Herzenberg with a FACS, circa 1985. The father of FACS, Leonard “Len” A. Herzenberg of the Department of Genetics at the Stanford University School of Medicine, died on Sunday, October 27, 2013 at the age of 81. Len will be remembered as a deeply innovative scientist, a biotechnology founding figure, a life-long mentor and gentle teacher, an early and effective proponent of diversity in science, and a committed social philanthropist. He is survived by his wife, Leonore “Lee” A. Herzenberg, also of the Stanford Department of Genetics, their children Berry, Jana, John, and Rick, four grandchildren, and an international extended family of former students and postdocs whose lives and careers he and Lee touched and enriched. Len and Lee were a unique team, their partnership transcending essentially all of the humdrum drudgeries of laboratory management and academic piffle for more than five decades. Len’s contributions were all shared with Lee, and they were each other’s staunchest champions and toughest insider critics (2). FACS, in conjunction with fluorochrome-labeled Mabs detecting cell surface and intracellular … [↵][1]1To whom correspondence should be addressed. E-mail: dangl{at}email.unc.edu. [1]: #xref-corresp-1-1

CD56negCD16+ NK cells are mature NK cells generated from CD56+CD16+ NK cells during HIV-1 infection (P4438)

Abstract: A subset of CD3negCD56negCD16+ Natural Killer (NK) cells is highly expanded during chronic HIV-1 infection, and the role of this subset in HIV-1 pathogenesis remains unclear. The lack of NK cell lineage-specific markers has complicated the study of minor NK cell subpopulations. Using CD7 as an additional NK cell marker, we found that CD3negCD56negCD16+ cells are a mixed population of CD7+ NK cells and CD7neg myeloid cells. CD7+CD56negCD16+ NK cells are significantly expanded in HIV-1 infection. CD7+CD56negCD16+ NK cells are mature and express KIRs, NKG2A, NKG2C, and natural cytotoxicity receptors similar to CD7+CD56+CD16+ cells. CD7+CD56neg NK cells in healthy donors produced minimal IFNg following K562 target cell or IL-12 plus IL-18 stimulation; however, they did degranulate in response to K562 cells similar to CD7+CD56+ NK cells. HIV-1 infection resulted in reduced IFNg secretion following K562 or cytokine stimulation by both NK cell subsets compared to healthy donors. Decreased granzyme B and perforin expression and increased expression of CD107a in the absence of stimulation, particularly in HIV-1-infected subjects, suggests that CD7+CD56negCD16+ NK cells may have recently engaged target cells. CD7+CD56negCD16+ NK cells have increased expression of the aging-related cyclin-dependent kinase inhibitors p16/INK4a and p21/Waf1. Taken together, CD7+CD56negCD16+ NK cells appear to be mature NK cells generated from chronic target engagement.

Modulation of NKG2D for prolonging survival of a hematopoietic graft

Abstract: The present invention relates to methods and compositions for treating and/or preventing autoimmune and/or inflammatory disease. In particular, the present invention provides therapeutics for impairing the expansion and function of autoreactive T cells, NK cells and/or NKT cells, by modulating NKG2D.

NKG2D-Dependent Mechanism IL-21 Enhances Tumor Rejection through a

Abstract: Lewis L. LanierPallavur V. Sivakumar, Steven Hughes, Mark J. Smyth and Rayna Takaki, Yoshihiro Hayakawa, Andrew Nelson,http://www.jimmunol.org/content/175/4/2167J Immunol€2005; 175:2167-2173; ;Referenceshttp://www.jimmunol.org/content/175/4/2167.full#ref-list-1This article cites 40 articles, 24 of which you can access for free at: Subscriptionshttp://jimmunol.org/subscriptionsInformation about subscribing to The Journal of Immunology is online at: Permissionshttp://www.aai.org/ji/copyright.htmlSubmit copyright permission requests at: Email Alertshttp://jimmunol.org/cgi/alerts/etocReceive free email-alerts when new articles cite this article. Sign up at:

This information is current as X-Linked Lymphoproliferative Syndrome Natural Killer Cells as Revealed by the SAP in 2B4-Mediated Activation of Human Cutting Edge: Functional Requirement for

Abstract: Kim E. NicholsStuart G. Tangye, Joseph H. Phillips, Lewis L. Lanier andhttp://www.jimmunol.org/content/165/6/2932J Immunol€2000; 165:2932-2936; ;Referenceshttp://www.jimmunol.org/content/165/6/2932.full#ref-list-1This article cites 30 articles, 13 of which you can access for free at: Subscriptionshttp://jimmunol.org/subscriptionsInformation about subscribing to The Journal of Immunology is online at: Permissionshttp://www.aai.org/ji/copyright.htmlSubmit copyright permission requests at: Email Alertshttp://jimmunol.org/cgi/alerts/etocReceive free email-alerts when new articles cite this article. Sign up at: