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Nieminuszczy J, Martin PR, Broderick R, Krwawicz J, Kanellou A, Mocanu C, Bousgouni V, Smith C, Wen KK, Woodward BL, Bakal C, Shackley F, Aguilera A, Stewart GS, Vyas YM, Niedzwiedz W. Actin nucleators safeguard replication forks by limiting nascent strand degradation. bioRxiv 2023:2023.01.12.523639. [PMID: 36711944 PMCID: PMC9882250 DOI: 10.1101/2023.01.12.523639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Accurate genome replication is essential for all life and a key mechanism of disease prevention, underpinned by the ability of cells to respond to replicative stress (RS) and protect replication forks. These responses rely on the formation of Replication Protein A (RPA)-single stranded (ss) DNA complexes, yet this process remains largely uncharacterized. Here we establish that actin nucleation-promoting factors (NPFs) associate with replication forks, promote efficient DNA replication and facilitate association of RPA with ssDNA at sites of RS. Accordingly, their loss leads to deprotection of ssDNA at perturbed forks, impaired ATR activation, global replication defects and fork collapse. Supplying an excess of RPA restores RPA foci formation and fork protection, suggesting a chaperoning role for actin nucleators (ANs) (i.e., Arp2/3, DIAPH1) and NPFs (i.e, WASp, N-WASp) in regulating RPA availability upon RS. We also discover that β-actin interacts with RPA directly in vitro , and in vivo a hyper-depolymerizing β-actin mutant displays a heightened association with RPA and the same dysfunctional replication phenotypes as loss of ANs/NPFs, which contrasts with the phenotype of a hyper-polymerizing β-actin mutant. Thus, we identify components of actin polymerization pathways that are essential for preventing ectopic nucleolytic degradation of perturbed forks by modulating RPA activity.
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Affiliation(s)
| | - Peter R. Martin
- Cancer Biology, The Institute of Cancer Research, London, SW3 6JB, UK
| | - Ronan Broderick
- Cancer Biology, The Institute of Cancer Research, London, SW3 6JB, UK
| | - Joanna Krwawicz
- Cancer Biology, The Institute of Cancer Research, London, SW3 6JB, UK
| | | | - Camelia Mocanu
- Cancer Biology, The Institute of Cancer Research, London, SW3 6JB, UK
| | - Vicky Bousgouni
- Cancer Biology, The Institute of Cancer Research, London, SW3 6JB, UK
| | - Charlotte Smith
- Cancer Biology, The Institute of Cancer Research, London, SW3 6JB, UK
| | - Kuo-Kuang Wen
- Department of Pediatrics, Division of Pediatric Hematology-Oncology, PennState College of Medicine, PennState Health Children’s Hospital, Hershey, Pennsylvania 17033, USA
| | - Beth L. Woodward
- Genome Stability and Human Disease Laboratory, Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Chris Bakal
- Cancer Biology, The Institute of Cancer Research, London, SW3 6JB, UK
| | - Fiona Shackley
- Paediatric Immunology, Allergy and Infectious Diseases, Sheffield Children's Hospital NHS Foundation Trust, Sheffield, UK
| | - Andres Aguilera
- Centro Andaluz de Biologia Molecular y Medicina Regenerativa CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, Seville, Spain
| | - Grant S. Stewart
- Genome Stability and Human Disease Laboratory, Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Yatin M. Vyas
- Department of Pediatrics, Division of Pediatric Hematology-Oncology, PennState College of Medicine, PennState Health Children’s Hospital, Hershey, Pennsylvania 17033, USA
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Han SS, Wen KK, Vyas YM. Deficiency of Wiskott-Aldrich syndrome protein has opposing effect on the pro-oncogenic pathway activation in nonmalignant versus malignant lymphocytes. Oncogene 2020; 40:345-354. [PMID: 33139832 DOI: 10.1038/s41388-020-01533-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 10/13/2020] [Accepted: 10/19/2020] [Indexed: 01/23/2023]
Abstract
Immunodeficiency is associated with cancer risk. Accordingly, hematolymphoid cancers develop in Wiskott-Aldrich syndrome (WAS), an X-linked primary immunodeficiency disorder (PID) resulting from the deficiency of WAS-protein (WASp) expressed predominantly in the hematolymphoid cell lineages. Despite the correlation between WASp deficiency and hematolymphoid cancers, the molecular mechanism underlying the oncogenic role of WASp is incompletely understood. Employing the WASp-sufficient and WASp-deficient cell-pair model of human T and B lymphocytes, we show that WASp deficiency differentially influences hyperactivation versus inhibition of both CDC42:ERK1/2 and NF-κB:AP-1 pro-oncogenic signaling pathways in nonmalignant versus malignant T and B lymphocytes. Furthermore, WASp deficiency induces a cell-type specific up/down-modulation of the DNA-binding activities of NF-κB, AP-1, and multiple other transcription factors with known roles in oncogenesis. We propose that WASp functions as a putative "tumor-suppressor" protein in normal T and B cells, and "oncoprotein" in a subset of established T and B cell malignancies that are not associated with the NPM-ALK fusion.
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Affiliation(s)
- Seong-Su Han
- Division of Pediatric Hematology-Oncology, Carver College of Medicine and the Stead Family University of Iowa Children's Hospital, Iowa City, IA, 52242, USA
| | - Kuo-Kuang Wen
- Division of Pediatric Hematology-Oncology, Carver College of Medicine and the Stead Family University of Iowa Children's Hospital, Iowa City, IA, 52242, USA
| | - Yatin M Vyas
- Division of Pediatric Hematology-Oncology, Carver College of Medicine and the Stead Family University of Iowa Children's Hospital, Iowa City, IA, 52242, USA.
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Wen KK, Han SS, Vyas YM. Wiskott-Aldrich syndrome protein senses irradiation-induced DNA damage to coordinate the cell-protective Golgi dispersal response in human T and B lymphocytes. J Allergy Clin Immunol 2019; 145:324-334. [PMID: 31604087 DOI: 10.1016/j.jaci.2019.09.026] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 09/01/2019] [Accepted: 09/24/2019] [Indexed: 12/20/2022]
Abstract
BACKGROUND Wiskott-Aldrich syndrome (WAS) is an X-linked primary immune deficiency disorder resulting from Wiskott-Aldrich syndrome protein (WASp) deficiency. Lymphocytes from patients with WAS manifest increased DNA damage and lymphopenia from cell death, yet how WASp influences DNA damage-linked cell survival is unknown. A recently described mechanism promoting cell survival after ionizing radiation (IR)-induced DNA damage involves fragmentation and dispersal of the Golgi apparatus, known as the Golgi-dispersal response (GDR), which uses the Golgi phosphoprotein 3 (GOLPH3)-DNA-dependent protein kinase (DNA-PK)-myosin XVIIIA-F-actin signaling pathway. OBJECTIVE We sought to define WASp's role in the DNA damage-induced GDR and its disruption as a contributor to the development of radiosensitivity-linked immunodeficiency in patients with WAS. METHODS In human TH and B-cell culture systems, DNA damage-induced GDR elicited by IR or radiomimetic chemotherapy was monitored in the presence or absence of WASp or GOLPH3 alone or both together. RESULTS WASp deficiency completely prevents the development of IR-induced GDR in human TH and B cells, despite the high DNA damage load. Loss of WASp impedes nuclear translocation of GOLPH3 and its colocalization with the DNA-dependent protein kinase catalytic subunit (DNA-PKcs). Surprisingly, however, depletion of GOLPH3 alone or depolymerization of F-actin in WASp-sufficient TH cells still allows development of robust GDR, suggesting that WASp, but not GOLPH3, is essential for GDR and cell survival after IR-induced DNA-damage in human lymphocytes. CONCLUSION The study identifies WASp as a novel effector of the nucleus-to-Golgi cell-survival pathway triggered by IR-induced DNA damage in cells of the hematolymphoid lineage and proposes an impaired GDR as a new cause for development of a "radiosensitive" form of immune dysregulation in patients with WAS.
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Affiliation(s)
- Kuo-Kuang Wen
- Division of Pediatric Hematology-Oncology, University of Iowa Carver College of Medicine, and the Stead Family University of Iowa Children's Hospital, Iowa City, Iowa
| | - Seong-Su Han
- Division of Pediatric Hematology-Oncology, University of Iowa Carver College of Medicine, and the Stead Family University of Iowa Children's Hospital, Iowa City, Iowa
| | - Yatin M Vyas
- Division of Pediatric Hematology-Oncology, University of Iowa Carver College of Medicine, and the Stead Family University of Iowa Children's Hospital, Iowa City, Iowa.
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Sarkar K, Han SS, Wen KK, Ochs HD, Dupré L, Seidman MM, Vyas YM. R-loops cause genomic instability in T helper lymphocytes from patients with Wiskott-Aldrich syndrome. J Allergy Clin Immunol 2017; 142:219-234. [PMID: 29248492 DOI: 10.1016/j.jaci.2017.11.023] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Revised: 11/07/2017] [Accepted: 11/10/2017] [Indexed: 02/08/2023]
Abstract
BACKGROUND Wiskott-Aldrich syndrome (WAS), X-linked thrombocytopenia (XLT), and X-linked neutropenia, which are caused by WAS mutations affecting Wiskott-Aldrich syndrome protein (WASp) expression or activity, manifest in immunodeficiency, autoimmunity, genomic instability, and lymphoid and other cancers. WASp supports filamentous actin formation in the cytoplasm and gene transcription in the nucleus. Although the genetic basis for XLT/WAS has been clarified, the relationships between mutant forms of WASp and the diverse features of these disorders remain ill-defined. OBJECTIVE We sought to define how dysfunctional gene transcription is causally linked to the degree of TH cell deficiency and genomic instability in the XLT/WAS clinical spectrum. METHODS In human TH1- or TH2-skewing cell culture systems, cotranscriptional R-loops (RNA/DNA duplex and displaced single-stranded DNA) and DNA double-strand breaks (DSBs) were monitored in multiple samples from patients with XLT and WAS and in normal T cells depleted of WASp. RESULTS WASp deficiency provokes increased R-loops and R-loop-mediated DSBs in TH1 cells relative to TH2 cells. Mechanistically, chromatin occupancy of serine 2-unphosphorylated RNA polymerase II is increased, and that of topoisomerase 1, an R-loop preventing factor, is decreased at R-loop-enriched regions of IFNG and TBX21 (TH1 genes) in TH1 cells. These aberrations accompany increased unspliced (intron-retained) and decreased spliced mRNA of IFNG and TBX21 but not IL13 (TH2 gene). Significantly, increased cellular load of R-loops and DSBs, which are normalized on RNaseH1-mediated suppression of ectopic R-loops, inversely correlates with disease severity scores. CONCLUSION Transcriptional R-loop imbalance is a novel molecular defect causative in TH1 immunodeficiency and genomic instability in patients with WAS. The study proposes that cellular R-loop load could be used as a potential biomarker for monitoring symptom severity and prognostic outcome in the XLT-WAS clinical spectrum and could be targeted therapeutically.
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Affiliation(s)
- Koustav Sarkar
- Division of Pediatric Hematology-Oncology, Carver College of Medicine and the University of Iowa Stead Family Children's Hospital, Iowa City, Md
| | - Seong-Su Han
- Division of Pediatric Hematology-Oncology, Carver College of Medicine and the University of Iowa Stead Family Children's Hospital, Iowa City, Md
| | - Kuo-Kuang Wen
- Division of Pediatric Hematology-Oncology, Carver College of Medicine and the University of Iowa Stead Family Children's Hospital, Iowa City, Md
| | - Hans D Ochs
- Center for Immunity and Immunotherapies, Seattle Children's Research Institute, University of Washington, Seattle, Md
| | - Loïc Dupré
- INSERM, UMR1043, Centre de Physiopathologie de Toulouse Purpan, Toulouse, Md; Université Toulouse III Paul-Sabatier, Toulouse, Md; CNRS, UMR5282, Toulouse, Md; Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, Vienna, Md; CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Md
| | - Michael M Seidman
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health (NIH), NIH Biomedical Research Center, Baltimore, Md
| | - Yatin M Vyas
- Division of Pediatric Hematology-Oncology, Carver College of Medicine and the University of Iowa Stead Family Children's Hospital, Iowa City, Md.
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El-Sheikh AA, Hashem H, Holman C, Vyas YM. Congenital dyserythropoietic anemia type I presenting as persistent pulmonary hypertension with pigeon chest deformity. Pediatr Blood Cancer 2014; 61:1460-2. [PMID: 24420417 DOI: 10.1002/pbc.24945] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Accepted: 12/22/2013] [Indexed: 11/11/2022]
Abstract
Congenital dyserythropoietic anemia (CDA) type-1 is a rare genetic disorder of ineffective erythropoiesis, which manifests in macrocytic anemia. We report a CDA1 patient who as a newborn presented with macrocytic anemia and persistent pulmonary hypertension of the newborn (PPHN) requiring mechanical ventilation. Post-infancy, the patient developed acral dysmorphism and pectus excavatum the latter rarely found in CDA1. Patient is a compound heterozygote for a known maternal-derived missense-mutation (c.1796A > G/p.Asn589Ser) and a novel paternal-derived deletion-mutation (c.1104_1106del/Phe365del) in CDAN1. This report highlights the importance of recognizing PPHN as a presenting symptom of CDA1 and expands the repertoire of the accompanying mutations and axial skeletal malformations.
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Affiliation(s)
- Ayman A El-Sheikh
- Pediatric Hematology Oncology, University of Iowa Children's Hospital, Iowa City, Iowa
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Sadhukhan S, Sarkar K, Taylor M, Candotti F, Vyas YM. Nuclear role of WASp in gene transcription is uncoupled from its ARP2/3-dependent cytoplasmic role in actin polymerization. J Immunol 2014; 193:150-60. [PMID: 24872192 DOI: 10.4049/jimmunol.1302923] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Defects in Wiskott-Aldrich Syndrome protein (WASp) underlie development of WAS, an X-linked immunodeficiency and autoimmunity disorder of childhood. Nucleation-promoting factors (NPFs) of the WASp family generate F-actin in the cytosol via the VCA (verprolin-homology, cofilin-homology, and acidic) domain and support RNA polymerase II-dependent transcription in the nucleus. Whether nuclear-WASp requires the integration of its actin-related protein (ARP)2/3-dependent cytoplasmic function to reprogram gene transcription, however, remains unresolved. Using the model of human TH cell differentiation, we find that WASp has a functional nuclear localizing and nuclear exit sequences, and accordingly, its effects on transcription are controlled mainly at the level of its nuclear entry and exit via the nuclear pore. Human WASp does not use its VCA-dependent, ARP2/3-driven, cytoplasmic effector mechanisms to support histone H3K4 methyltransferase activity in the nucleus of TH1-skewed cells. Accordingly, an isolated deficiency of nuclear-WASp is sufficient to impair the transcriptional reprogramming of TBX21 and IFNG promoters in TH1-skewed cells, whereas an isolated deficiency of cytosolic-WASp does not impair this process. In contrast, nuclear presence of WASp in TH2-skewed cells is small, and its loss does not impair transcriptional reprogramming of GATA3 and IL4 promoters. Our study unveils an ARP2/3:VCA-independent function of nuclear-WASp in TH1 gene activation that is uncoupled from its cytoplasmic role in actin polymerization.
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Affiliation(s)
- Sanjoy Sadhukhan
- Division of Pediatric Hematology-Oncology, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA 15213
| | - Koustav Sarkar
- Division of Pediatric Hematology-Oncology, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA 15213; Division of Pediatric Hematology-Oncology, University of Iowa Children's Hospital, Iowa City, IA 52242; and
| | - Matthew Taylor
- Division of Pediatric Hematology-Oncology, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA 15213
| | - Fabio Candotti
- Genetics and Molecular Biology Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892
| | - Yatin M Vyas
- Division of Pediatric Hematology-Oncology, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA 15213; Division of Pediatric Hematology-Oncology, University of Iowa Children's Hospital, Iowa City, IA 52242; and
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Taylor MD, Sadhukhan S, Kottangada P, Ramgopal A, Sarkar K, D'Silva S, Selvakumar A, Candotti F, Vyas YM. Nuclear role of WASp in the pathogenesis of dysregulated TH1 immunity in human Wiskott-Aldrich syndrome. Sci Transl Med 2010; 2:37ra44. [PMID: 20574068 DOI: 10.1126/scitranslmed.3000813] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The clinical symptomatology in the X-linked Wiskott-Aldrich syndrome (WAS), a combined immunodeficiency and autoimmune disease resulting from WAS protein (WASp) deficiency, reflects the underlying coexistence of an impaired T helper 1 (TH1) immunity alongside intact TH2 immunity. This suggests a role for WASp in patterning T(H) subtype immunity, yet the molecular basis for the TH1-TH2 imbalance in human WAS is unknown. We have discovered a nuclear role for WASp in the transcriptional regulation of the TH1 regulator gene TBX21 at the chromatin level. In primary TH1-differentiating cells, a fraction of WASp is found in the nucleus, where it is recruited to the proximal promoter locus of the TBX21 gene, but not to the core promoter of GATA3 (a TH2 regulator gene) or RORc (a TH17 regulator gene). Genome-wide mapping demonstrates association of WASp in vivo with the gene-regulatory network that orchestrates TH1 cell fate choice in the human TH cell genome. Functionally, nuclear WASp associates with H3K4 trimethyltransferase [RBBP5 (retinoblastoma-binding protein 5)] and H3K9/H3K36 tridemethylase [JMJD2A (Jumonji domain-containing protein 2A)] proteins, and their enzymatic activity in vitro and in vivo is required for achieving transcription-permissive chromatin dynamics at the TBX21 proximal promoter in primary differentiating TH1 cells. During TH1 differentiation, the loss of WASp accompanies decreased enrichment of RBBP5 and, in a subset of WAS patients, also of filamentous actin at the TBX21 proximal promoter locus. Accordingly, human WASp-deficient TH cells, from natural mutation or RNA interference-mediated depletion, demonstrate repressed TBX21 promoter dynamics when driven under TH1-differentiating conditions. These chromatin derangements accompany deficient T-BET messenger RNA and protein expression and impaired TH1 function, defects that are ameliorated by reintroducing WASp. Our findings reveal a previously unappreciated role of WASp in the epigenetic control of T-BET transcription and provide a new mechanism for the pathogenesis of WAS by linking aberrant histone methylation at the TBX21 promoter to dysregulated adaptive immunity.
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Affiliation(s)
- Matthew D Taylor
- Division of Pediatric Hematology-Oncology, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA 15213, USA
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Kreindler JL, Steele C, Nguyen N, Chan YR, Pilewski JM, Alcorn JF, Vyas YM, Aujla SJ, Finelli P, Blanchard M, Zeigler SF, Logar A, Hartigan E, Kurs-Lasky M, Rockette H, Ray A, Kolls JK. Vitamin D3 attenuates Th2 responses to Aspergillus fumigatus mounted by CD4+ T cells from cystic fibrosis patients with allergic bronchopulmonary aspergillosis. J Clin Invest 2010; 120:3242-54. [PMID: 20714107 DOI: 10.1172/jci42388] [Citation(s) in RCA: 115] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2010] [Accepted: 07/07/2010] [Indexed: 01/21/2023] Open
Abstract
Allergic bronchopulmonary aspergillosis (ABPA) is caused by a dominant Th2 immune response to antigens derived from the opportunistic mold Aspergillus, most commonly Aspergillus fumigatus. It occurs in 4%-15% of patients with cystic fibrosis (CF); however, not all patients with CF infected with A. fumigatus develop ABPA. Therefore, we compared cohorts of A. fumigatus-colonized CF patients with and without ABPA to identify factors mediating tolerance versus sensitization. We found that the costimulatory molecule OX40 ligand (OX40L) was critical in driving Th2 responses to A. fumigatus in peripheral CD4+ T cells isolated from patients with ABPA. In contrast, CD4+ T cells from the non-ABPA cohort did not mount enhanced Th2 responses in vitro and contained a higher frequency of TGF-beta-expressing regulatory T cells. Heightened Th2 reactivity in the ABPA cohort correlated with lower mean serum vitamin D levels. Further, in vitro addition of 1,25 OH-vitamin D3 substantially reduced DC expression of OX40L and increased DC expression of TGF-beta. This in vitro treatment also resulted in increased Treg TGF-beta expression and reduced Th2 responses by CD4+ T cells from patients with ABPA. These data provide rationale for a therapeutic trial of vitamin D to prevent or treat ABPA in patients with CF.
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Park JW, Kim HP, Lee SJ, Wang X, Wang Y, Ifedigbo E, Watkins SC, Ohba M, Ryter SW, Vyas YM, Choi AMK. Protein kinase C alpha and zeta differentially regulate death-inducing signaling complex formation in cigarette smoke extract-induced apoptosis. J Immunol 2008; 180:4668-78. [PMID: 18354190 DOI: 10.4049/jimmunol.180.7.4668] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Cigarette smoke, a major risk factor in emphysema, causes cell death by incompletely understood mechanisms. Death-inducing signaling complex (DISC) formation is an initial event in Fas-mediated apoptosis. We demonstrate that cigarette smoke extract (CSE) induces DISC formation in human lung fibroblasts (MRC-5) and promotes DISC trafficking from the Golgi complex to membrane lipid rafts. We demonstrate a novel role of protein kinase C (PKC) in the regulation of DISC formation and trafficking. The PKC isoforms, PKCalpha, zeta, epsilon, and eta, were activated by CSE exposure. Overexpression of wild-type PKCalpha inhibited, while PKCzeta promoted, CSE-induced cell death. Dominant-negative (dn)PKCzeta protected against CSE-induced cell death by suppressing DISC formation and caspase-3 activation, while dnPKCalpha enhanced cell death by promoting these events. DISC formation was augmented by wortmannin, an inhibitor of PI3K. CSE-induced Akt phosphorylation was reduced by dnPKCalpha, but it was increased by dnPKCzeta. Expression of PKCalpha in vivo inhibited DISC formation, caspase-3/8 activation, lung injury, and cell death after prolonged cigarette smoke exposure, whereas expression of PKCzeta promoted caspase-3 activation. In conclusion, CSE-induced DISC formation is differentially regulated by PKCalpha and PKCzeta via the PI3K/Akt pathway. These results suggest that modulation of PKC may have therapeutic potential in the prevention of smoke-related lung injury.
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Affiliation(s)
- Jeong-Woong Park
- Department of Pulmonary and Critical Care Medicine, Gachon Medical School, Gil Medical Center, Inchon, Republic of Korea
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Luty WH, Rodeberg D, Parness J, Vyas YM. Antiparallel segregation of notch components in the immunological synapse directs reciprocal signaling in allogeneic Th:DC conjugates. J Immunol 2007; 179:819-29. [PMID: 17617572 DOI: 10.4049/jimmunol.179.2.819] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Direct T cell allorecognition underlies the development of a vigorous immune response in the clinical setting of acute graft rejection. The Notch pathway is an important regulator of Th immune responses, yet the molecular underpinnings of directional Notch signaling, otherwise critical for binary cell fate decisions, are unknown during autologous or allogeneic Th:DC interactions. Using the development of immune synapses (IS) in the allogeneic, human physiological Th:DC interaction, we demonstrate that Th-Notch1 receptor and DC-Notch ligands (Delta-like1, Jagged1) cluster in their apposed central-supramolecular-activation-clusters (cSMAC), whereas DC-Notch1 receptor and Th-Notch ligands cluster in their apposed peripheral-SMAC (pSMAC). Numb, a negative regulator of Notch, is excluded from the IS-microdomains where Notch1 receptor accumulates. This antiparallel arrangement across the partnering halves of the IS supports reciprocal Notch signal propagation in the DC-to-Th direction via the cSMAC and Th-to-DC direction via the pSMAC. As a result, processed Notch1 receptor (Notch-intracellular-domain, NICD1) and its ligands, as well as their downstream targets, HES-1 and phosphorylated-STAT3, accumulate in the nuclei of both cell-types. There is also enhancement of GLUT1 expression in both cell-types, as well as increased production of Th-IFN-gamma. Significantly, neutralizing Notch1R Ab inhibits NICD1 and HES-1 nuclear translocation, and production of IFN-gamma. In contrast, the IS formed during Ag-nonspecific, autologous Th:DC interaction is immature, resulting in failure of Notch1 receptor segregation and subsequent nuclear translocation of NICD1. Our results provide the first evidence for the asymmetric recruitment of Notch components in the Th:DC immunological synapse, which regulates the bidirectional Notch signal propagation.
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Affiliation(s)
- Winifred H Luty
- Division of Pediatric Hematology-Oncology and Bone Marrow Transplantation, Children's Hospital of Pittsburgh, University of Pittsburgh, PA 15213, USA
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Arora M, Chen L, Paglia M, Gallagher I, Allen JE, Vyas YM, Ray A, Ray P. Simvastatin promotes Th2-type responses through the induction of the chitinase family member Ym1 in dendritic cells. Proc Natl Acad Sci U S A 2006; 103:7777-82. [PMID: 16682645 PMCID: PMC1472521 DOI: 10.1073/pnas.0508492103] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2005] [Indexed: 01/28/2023] Open
Abstract
Statins, best known for their lipid-lowering actions, also possess immunomodulatory properties. Recent studies have shown a Th2-biasing effect of statins, although the underlying mechanism has not been identified. In this study, we investigated whether simvastatin can exercise a Th2-promoting effect through modulation of function of dendritic cells (DCs) without direct interaction with CD4+ T cells. Exposure of DCs to simvastatin induced the differentiation of a distinct subset of DCs characterized by a high expression of B220. These simvastatin-conditioned DCs up-regulated GATA-3 expression and down-regulated T-bet expression in cocultured CD4+ T cells in the absence of additional simvastatin added to the coculture. The Th2-biased transcription factor profile induced by simvastatin-treated DCs also was accompanied by increased Th2 (IL-4, IL-5, and IL-13) and decreased Th1 (IFN-gamma) cytokine secretion from the T cells. The Th2-promoting effect of simvastatin was found to depend on the chitinase family member Ym1, known to be a lectin. Anti-Ym1 antibody abolished the Th2-promoting effect of simvastatin-treated DCs. Also, simvastatin was unable to augment Ym1 expression in DCs developed from STAT6-/- or IL-4R alpha-/- mice. Thus, modulation of Ym1 production by DCs identifies a previously undescribed mechanism of Th2 polarization by statin.
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Affiliation(s)
- Meenakshi Arora
- Departments of *Medicine, Division of Pulmonary, Allergy, and Critical Care Medicine and
| | - Li Chen
- Departments of *Medicine, Division of Pulmonary, Allergy, and Critical Care Medicine and
| | - Melissa Paglia
- Departments of *Medicine, Division of Pulmonary, Allergy, and Critical Care Medicine and
| | - Iain Gallagher
- Institute of Immunology & Infection Research, University of Edinburgh, Edinburgh EH9 3JT, United Kingdom; and
| | - Judith E. Allen
- Institute of Immunology & Infection Research, University of Edinburgh, Edinburgh EH9 3JT, United Kingdom; and
| | - Yatin M. Vyas
- Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
- Department of Pediatrics, Division of Hematology and Oncology, Children’s Hospital of Pittsburgh, Pittsburgh, PA 15213
| | - Anuradha Ray
- Departments of *Medicine, Division of Pulmonary, Allergy, and Critical Care Medicine and
- Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
| | - Prabir Ray
- Departments of *Medicine, Division of Pulmonary, Allergy, and Critical Care Medicine and
- Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
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12
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Chou AJ, Merola PR, Wexler LH, Gorlick RG, Vyas YM, Healey JH, LaQuaglia MP, Huvos AG, Meyers PA. Treatment of osteosarcoma at first recurrence after contemporary therapy: the Memorial Sloan-Kettering Cancer Center experience. Cancer 2006; 104:2214-21. [PMID: 16206297 DOI: 10.1002/cncr.21417] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Overall survival after recurrence of osteosarcoma (OS) is < 30%. The authors reported their experience treating recurrent OS at the time of first recurrence (R1). METHODS Patients with high-grade OS who achieved complete disease remission (CR) after primary surgery and chemotherapy, and patients who were treated at R1 at Memorial Sloan-Kettering Cancer Center (New York, NY) after 1990 were analyzed by retrospective chart review. RESULTS For 43 eligible patients, the median time to R1 from initial diagnosis was 21.7 months (range, 4.6-135.7 mos). The lungs were the most common sites of disease recurrence (n = 33 of 43). With a median follow-up of 15.2 months (range, 0.7-158.3 mos) after R1, 15 of 43 (35%) patients were alive. Four of 43 patients were treated with surgery alone (3 patients were alive and 1 had died of progressive disease at the time of last follow-up). Due to unresectable disease, eight patients received only chemotherapy, none of whom survived. For patients with disease recurrence treated with chemotherapy and surgery (n = 31), 22 patients achieved a second CR (CR2). Nine patients were alive and in disease remission (29%) at the time of last follow-up. Twenty-three patients received ifosfamide as part of their retrieval regimen. Of the 18 who achieved a CR2, 8 experienced disease recurrence, 7 remain alive in CR2, and 3 died due to toxicity. Eight patients did not receive ifosfamide. Of these, 4 achieved a CR2 but 3 subsequently experienced disease recurrence. CONCLUSIONS At R1, 22 of 31 patients achieved a CR2 with aggressive surgery and chemotherapy. The majority of these patients subsequently developed a disease recurrence. Patients appeared to benefit from the addition of ifosfamide to their retrieval regimens. In the end, the role of chemotherapy in recurrent OS continues to remain undefined.
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Affiliation(s)
- Alexander J Chou
- Department of Pediatrics, Memorial Sloan-Kettering Cancer Center, New York, New York 10021, USA
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Huang W, Ochs HD, Dupont B, Vyas YM. The Wiskott-Aldrich Syndrome Protein Regulates Nuclear Translocation of NFAT2 and NF-κB (RelA) Independently of Its Role in Filamentous Actin Polymerization and Actin Cytoskeletal Rearrangement. J Immunol 2005; 174:2602-11. [PMID: 15728466 DOI: 10.4049/jimmunol.174.5.2602] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Effector functions mediated by NK cells involve cytotoxicity and transcription-dependent production and release of cytokines and chemokines. Although the JAK/STAT pathway mediates lymphokine-induced transcriptional regulation in NK cells, very little is known about transcriptional regulation induced during cell-cell contact. We demonstrate that the Wiskott-Aldrich syndrome protein (WASp) is an important component for integration of signals leading to nuclear translocation of NFAT2 and NF-kappaB (RelA) during cell-cell contact and NKp46-dependent signaling. This WASp function is independent of its known role in F-actin polymerization and cytoskeletal rearrangement. Absence of WASp results in decreased accumulation of calcineurin, WASp-interacting protein, and molecules upstream of calcium mobilization, i.e., activated ZAP70 and phospholipase C-gamma1, in the disorganized NK cell immune synapse. Production of GM-CSF, but not IFN-gamma, is decreased, while natural cytotoxicity of Wiskott-Aldrich syndrome-NK cells is maintained. Our results indicate that WASp independently regulates its dual functions, i.e., actin cytoskeletal remodeling and transcription in NK cells.
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Affiliation(s)
- Winifred Huang
- Department of Pediatrics, Memorial Sloan-Kettering Cancer Center, Sloan-Kettering Institute for Cancer Research, New York, NY 10021, USA
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Vyas YM, Maniar H, Lyddane CE, Sadelain M, Dupont B. Ligand binding to inhibitory killer cell Ig-like receptors induce colocalization with Src homology domain 2-containing protein tyrosine phosphatase 1 and interruption of ongoing activation signals. J Immunol 2004; 173:1571-8. [PMID: 15265884 DOI: 10.4049/jimmunol.173.3.1571] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Interaction of NK cells with target cells leads to formation of an immunological synapse (IS) at the contact site. NK cells form two distinctly different IS, the inhibitory NK cell IS (NKIS) and the cytolytic NKIS. Cognate ligand binding is sufficient to induce clustering of inhibitory killer cell Ig-like receptors (KIR) and phosphorylation of both the receptor and the phosphatase Src homology domain 2-containing protein tyrosine phosphatase 1 (SHP-1). Recruitment and activation of SHP-1 by a signaling competent inhibitory receptor are essential early events for NK cell inhibition. We have in the present study used three-dimensional immunofluorescence microscopy to analyze distribution of inhibitory KIR, SHP-1, LFA-1, and lipid rafts within the NKIS during cytolytic and noncytolytic interactions. NK clones retrovirally transduced with the inhibitory KIR2DL3 gene fused to GFP demonstrate colocalization of KIR2DL3 with SHP-1 in the center of early inhibitory NKIS. Ligand binding translocates the receptor to the center of the IS where activation signals are accumulating and provides a docking site for SHP-1. SHP-1 and rafts cluster in the center of early inhibitory NKIS and late cytolytic NKIS, and whereas rafts continue to increase in size in cytolytic conjugates, they are rapidly dissolved in inhibitory conjugates. Furthermore, rafts are essential only for cytolytic, not for inhibitory, outcome. These results indicate that the outcome of NK cell-target cell interactions is dictated by early quantitative differences in cumulative activating and inhibitory signals.
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MESH Headings
- Cytotoxicity, Immunologic
- Enzyme Activation/drug effects
- Genes, Reporter
- Green Fluorescent Proteins
- Humans
- Imaging, Three-Dimensional
- Intracellular Signaling Peptides and Proteins
- Killer Cells, Natural/drug effects
- Killer Cells, Natural/immunology
- Killer Cells, Natural/metabolism
- Killer Cells, Natural/ultrastructure
- Ligands
- Luminescent Proteins/analysis
- Luminescent Proteins/genetics
- Lymphocyte Function-Associated Antigen-1/metabolism
- Membrane Microdomains/metabolism
- Microscopy, Fluorescence/methods
- Phosphorylation/drug effects
- Protein Phosphatase 1
- Protein Processing, Post-Translational/drug effects
- Protein Tyrosine Phosphatase, Non-Receptor Type 6
- Protein Tyrosine Phosphatases/metabolism
- Receptors, Immunologic/drug effects
- Receptors, Immunologic/genetics
- Receptors, Immunologic/physiology
- Receptors, KIR
- Receptors, KIR2DL3
- Recombinant Fusion Proteins/analysis
- Transduction, Genetic
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Affiliation(s)
- Yatin M Vyas
- Department of Pediatrics, Sloan-Kettering Institute for Cancer Research, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA
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Doubrovina ES, Doubrovin MM, Vider E, Sisson RB, O'Reilly RJ, Dupont B, Vyas YM. Evasion from NK cell immunity by MHC class I chain-related molecules expressing colon adenocarcinoma. J Immunol 2004; 171:6891-9. [PMID: 14662896 DOI: 10.4049/jimmunol.171.12.6891] [Citation(s) in RCA: 239] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Evasion of host immune responses is well documented for viruses and may also occur during tumor immunosurveillance. The mechanisms involve alterations in MHC class I expression, Ag processing and presentation, chemokine and cytokine production, and lymphocyte receptor expression. Epithelial tumors overexpress MHC class I chain-related (MIC) molecules, which are ligands for the activating receptor NKG2D on NK and T cells. We report that NK cells from patients with colorectal cancer lack expression of activating NKG2D and chemokine CXCR1 receptors, both of which are internalized. Serum levels of soluble MIC (sMIC) are elevated and are responsible for down-modulation of NKG2D and CXCR1. In contrast, high serum levels of CXC ligands, IL-8, and epithelial-neutrophil-activating peptide (ENA-78) do not down-modulate CXCR1. In vitro, internalization of NKG2D and CXCR1 occurs within 4 and 24 h, respectively, of incubating normal NK cells with sMIC-containing serum. Furthermore, natural cytotoxicity receptor NKp44 and chemokine receptor CCR7 are also down-modulated in IL-2-activated NK cells cocultured in MIC-containing serum-an effect secondary to the down-modulation of NKG2D and not directly caused by physical association with sMIC. The patients' NK cells up-regulate expression of NKG2D, NKp44, CXCR1, and CCR7 when cultured in normal serum or anti-MIC Ab-treated autologous serum. NKG2D(+) but not NKG2D(-) NK cells are tumoricidal in vitro, and in vivo they selectively traffic to the xenografted carcinoma, form immunological synapse with tumor cells, and significantly retard tumor growth in the SCID mice. These results suggest that circulating sMIC in the cancer patients deactivates NK immunity by down-modulating important activating and chemokine receptors.
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MESH Headings
- Adenocarcinoma/immunology
- Adenocarcinoma/metabolism
- Adenocarcinoma/pathology
- Animals
- Cell Line, Transformed
- Coculture Techniques
- Colonic Neoplasms/immunology
- Colonic Neoplasms/metabolism
- Colonic Neoplasms/pathology
- Cytotoxicity, Immunologic/immunology
- Down-Regulation/immunology
- Growth Inhibitors/antagonists & inhibitors
- Growth Inhibitors/biosynthesis
- Histocompatibility Antigens Class I/biosynthesis
- Histocompatibility Antigens Class I/metabolism
- Histocompatibility Antigens Class I/physiology
- Humans
- Immunity, Cellular
- Killer Cells, Natural/immunology
- Killer Cells, Natural/metabolism
- Killer Cells, Natural/transplantation
- Ligands
- Mice
- Mice, SCID
- NK Cell Lectin-Like Receptor Subfamily K
- Neoplasm Proteins/biosynthesis
- Neoplasm Proteins/metabolism
- Neoplasm Proteins/physiology
- Neoplasm Transplantation
- Receptors, CCR7
- Receptors, Chemokine/antagonists & inhibitors
- Receptors, Chemokine/biosynthesis
- Receptors, Immunologic/antagonists & inhibitors
- Receptors, Immunologic/biosynthesis
- Receptors, Interleukin-8A/antagonists & inhibitors
- Receptors, Interleukin-8A/biosynthesis
- Receptors, Natural Killer Cell
- Solubility
- Transplantation, Heterologous
- Tumor Cells, Cultured
- Tumor Escape/immunology
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Affiliation(s)
- Ekaterina S Doubrovina
- Department of Pediatrics, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA
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Abstract
Recent applications of imaging approaches and other methods of cell biology have provided high-resolution visualization of the location of fluorescent proteins in living and fixed cells during cell-cell interactions between lymphocytes, antigen presenting cells and target cells. We review the composition and dynamics of molecular and cytoskeletal events occurring during natural killer cell interactions with susceptible and nonsusceptible target cells. The natural killer cell immune synapse and the concomitant changes in cytoskeletal components and cytoplasmic organelles are described. The findings are compared with the observations made in T helper cells and cytotoxic T cells. It is concluded that the cytolytic immune synapses display spatial-temporal dynamics that are accelerated as compared with T helper cells. In addition, the cytolytic conjugates have unique characteristics relating to their effector function. Furthermore, the natural killer cell immune synapses in cytolytic and noncytolytic interactions are distinctly different and display patterns consistent with characteristic signaling pathways identified in biochemical studies of disrupted cells. The precise relationship between different stages of the natural killer cell immune synapse formation and progression in signal transduction pathways is yet to be established.
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Affiliation(s)
- Yatin M Vyas
- Immunology Program, Sloan-Kettering Institute for Cancer Research, New York, NY 10021, USA
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Vyas YM, Maniar H, Dupont B. Cutting edge: differential segregation of the SRC homology 2-containing protein tyrosine phosphatase-1 within the early NK cell immune synapse distinguishes noncytolytic from cytolytic interactions. J Immunol 2002; 168:3150-4. [PMID: 11907066 DOI: 10.4049/jimmunol.168.7.3150] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Inhibitory NK receptors with ligand specificity for MHC class I recruit Src homology 2-containing protein tyrosine phosphatase-1 (SHP-1) phosphatase and prevent autocytotoxicity. Activation of SHP-1 depends upon Src kinase-mediated tyrosine phosphorylation of the cytoplasmic domain of the inhibitory receptor. In this study we demonstrate, by quantitative temporal analysis, that talin, Lck, and SHP-1 are recruited to the synapse within 1 min in both cytolytic and noncytolytic conjugates. Polarization of talin and Lck rapidly disappears in the noncytolytic interactions but persists in cytolytic interactions, where protein kinase C-theta;, Src homology 2 domain-containing leukocyte protein of 76 kDa, and lysosomes are recruited within 5 min. At 1 min SHP-1 clusters in the periphery of the cytolytic synapse, whereas it clusters in the center of the noncytolytic synapse. Lck has multifocal distribution in both synapses consistent with the shared requirement for early tyrosine phosphorylation. Our studies indicate that the spatial location of SHP-1 in the synapse distinguishes noncytolytic from cytolytic interactions within the first minute.
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Affiliation(s)
- Yatin M Vyas
- Immunology Program, Sloan-Kettering Institute for Cancer Research, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA
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Vyas YM, Mehta KM, Morgan M, Maniar H, Butros L, Jung S, Burkhardt JK, Dupont B. Spatial organization of signal transduction molecules in the NK cell immune synapses during MHC class I-regulated noncytolytic and cytolytic interactions. J Immunol 2001; 167:4358-67. [PMID: 11591760 DOI: 10.4049/jimmunol.167.8.4358] [Citation(s) in RCA: 146] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The cytolytic activity of NK cells is tightly regulated by inhibitory receptors specific for MHC class I Ags. We have investigated the composition of signal transduction molecules in the supramolecular activation clusters in the MHC class I-regulated cytolytic and noncytolytic NK cell immune synapses. KIR2DL3-positive NK clones that are specifically inhibited in their cytotoxicity by HLA-Cw*0304 and polyclonal human NK cells were used for conjugate formation with target cells that are either protected or are susceptible to NK cell-mediated cytotoxicity. Polarization of talin, microtubule-organizing center, and lysosomes occurred only during cytolytic interactions. The NK immune synapses were analyzed by three-dimensional immunofluorescence microscopy, which showed two distinctly different synaptic organizations in NK cells during cytolytic and noncytolytic interactions. The center of a cytolytic synapse with MHC class I-deficient target is comprised of a complex of signaling molecules including Src homology (SH)2-containing protein tyrosine phosphatase-1 (SHP-1). Closely related molecules with overlapping functions, such as the Syk kinases, SYK, and ZAP-70, and adaptor molecules, SH2 domain-containing leukocyte protein of 76 kDa and B cell linker protein, are expressed in activated NK cells and are all recruited to the center of the cytolytic synapse. In contrast, the noncytolytic synapse contains SHP-1, but is lacking other components of the central supramolecular activation cluster. These findings indicate a functional role for SHP-1 in both the cytolytic and noncytolytic interactions. We also demonstrate, in three-cell conjugates, that a single NK cell forms a cytolytic synapse with a susceptible target cell in the presence of both susceptible and nonsusceptible target cells.
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Affiliation(s)
- Y M Vyas
- Immunology Program, Sloan-Kettering Institute for Cancer Research, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA
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