1
|
Aziz F, Reddy K, Fernandez Vega V, Dey R, Hicks KA, Rao S, Jordan LO, Smith E, Shumate J, Scampavia L, Carpino N, Spicer TP, French JB. Rebamipide and Derivatives are Potent, Selective Inhibitors of Histidine Phosphatase Activity of the Suppressor of T Cell Receptor Signaling Proteins. J Med Chem 2024; 67:1949-1960. [PMID: 38252624 DOI: 10.1021/acs.jmedchem.3c01763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
The suppressor of T cell receptor signaling (Sts) proteins are negative regulators of immune signaling. Genetic inactivation of these proteins leads to significant resistance to infection. From a 590,000 compound high-throughput screen, we identified the 2-(1H)-quinolinone derivative, rebamipide, as a putative inhibitor of Sts phosphatase activity. Rebamipide, and a small library of derivatives, are competitive, selective inhibitors of Sts-1 with IC50 values from low to submicromolar. SAR analysis indicates that the quinolinone, the acid, and the amide moieties are all essential for activity. A crystal structure confirmed the SAR and reveals key interactions between this class of compound and the protein. Although rebamipide has poor cell permeability, we demonstrated that a liposomal preparation can inactivate the phosphatase activity of Sts-1 in cells. These studies demonstrate that Sts-1 enzyme activity can be pharmacologically inactivated and provide foundational tools and insights for the development of immune-enhancing therapies that target the Sts proteins.
Collapse
Affiliation(s)
- Faisal Aziz
- The Hormel Institute, University of Minnesota, Austin, Minnesota 55912, United States
| | - Kanamata Reddy
- The Hormel Institute, University of Minnesota, Austin, Minnesota 55912, United States
| | - Virneliz Fernandez Vega
- Department of Molecular Medicine, The Herbert Wertheim UF Scripps Institute, Jupiter, Florida 33458, United States
| | - Raja Dey
- The Hormel Institute, University of Minnesota, Austin, Minnesota 55912, United States
| | - Katherine A Hicks
- Department of Chemistry, State University of New York at Cortland, Cortland, New York 13045, United States
| | - Sumitha Rao
- Department of Molecular Medicine, The Herbert Wertheim UF Scripps Institute, Jupiter, Florida 33458, United States
| | - Luis Ortiz Jordan
- Department of Molecular Medicine, The Herbert Wertheim UF Scripps Institute, Jupiter, Florida 33458, United States
| | - Emery Smith
- Department of Molecular Medicine, The Herbert Wertheim UF Scripps Institute, Jupiter, Florida 33458, United States
| | - Justin Shumate
- Department of Molecular Medicine, The Herbert Wertheim UF Scripps Institute, Jupiter, Florida 33458, United States
| | - Louis Scampavia
- Department of Molecular Medicine, The Herbert Wertheim UF Scripps Institute, Jupiter, Florida 33458, United States
| | - Nicholas Carpino
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, New York 11790, United States
| | - Timothy P Spicer
- Department of Molecular Medicine, The Herbert Wertheim UF Scripps Institute, Jupiter, Florida 33458, United States
| | - Jarrod B French
- The Hormel Institute, University of Minnesota, Austin, Minnesota 55912, United States
| |
Collapse
|
2
|
Tsai YL, Arias-Badia M, Kadlecek TA, Lwin YM, Srinath A, Shah NH, Wang ZE, Barber D, Kuriyan J, Fong L, Weiss A. TCR signaling promotes formation of an STS1-Cbl-b complex with pH-sensitive phosphatase activity that suppresses T cell function in acidic environments. Immunity 2023; 56:2682-2698.e9. [PMID: 38091950 PMCID: PMC10785950 DOI: 10.1016/j.immuni.2023.11.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 08/11/2023] [Accepted: 11/14/2023] [Indexed: 12/18/2023]
Abstract
T cell responses are inhibited by acidic environments. T cell receptor (TCR)-induced protein phosphorylation is negatively regulated by dephosphorylation and/or ubiquitination, but the mechanisms underlying sensitivity to acidic environments are not fully understood. Here, we found that TCR stimulation induced a molecular complex of Cbl-b, an E3-ubiquitin ligase, with STS1, a pH-sensitive unconventional phosphatase. The induced interaction depended upon a proline motif in Cbl-b interacting with the STS1 SH3 domain. STS1 dephosphorylated Cbl-b interacting phosphoproteins. The deficiency of STS1 or Cbl-b diminished the sensitivity of T cell responses to the inhibitory effects of acid in an autocrine or paracrine manner in vitro or in vivo. Moreover, the deficiency of STS1 or Cbl-b promoted T cell proliferative and differentiation activities in vivo and inhibited tumor growth, prolonged survival, and improved T cell fitness in tumor models. Thus, a TCR-induced STS1-Cbl-b complex senses intra- or extra-cellular acidity and regulates T cell responses, presenting a potential therapeutic target for improving anti-tumor immunity.
Collapse
Affiliation(s)
- Yuan-Li Tsai
- Rosalind Russell and Ephraim P. Engleman Rheumatology Research Center, Division of Rheumatology, Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Marcel Arias-Badia
- Division of Hematology and Oncology, Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Theresa A Kadlecek
- Rosalind Russell and Ephraim P. Engleman Rheumatology Research Center, Division of Rheumatology, Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Yee May Lwin
- Division of Hematology and Oncology, Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Aahir Srinath
- Division of Hematology and Oncology, Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Neel H Shah
- Department of Chemistry, Columbia University, New York, NY 10027, USA
| | - Zhi-En Wang
- Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Diane Barber
- Department of Cell and Tissue Biology, University of California, San Francisco, San Francisco, CA 94143, USA
| | - John Kuriyan
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, USA
| | - Lawrence Fong
- Division of Hematology and Oncology, Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA; Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Arthur Weiss
- Rosalind Russell and Ephraim P. Engleman Rheumatology Research Center, Division of Rheumatology, Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA.
| |
Collapse
|
3
|
Zaman A, Diago Navarro E, Fries BC, Kim HK, Carpino N. Inactivation of the Sts enzymes promotes resistance to lethal Staphylococcus aureus infection. Infect Immun 2023; 91:e0026023. [PMID: 37725063 PMCID: PMC10580875 DOI: 10.1128/iai.00260-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 07/14/2023] [Indexed: 09/21/2023] Open
Abstract
Staphylococcus aureus is a highly infective Gram-positive bacterial pathogen that causes a wide range of diseases in both healthy and immunocompromised individuals. It can evade host immune defenses by expressing numerous virulence factors and toxins. Coupled with the inability of the human host to develop protective immunity against S. aureus, the emergence of antibiotic-resistant strains complicates treatment options. The non-canonical Sts phosphatases negatively regulate signaling pathways in varied immune cell types. To determine the role of the Sts proteins in regulating host responses to a Gram-positive microorganism, we investigated the response of mice lacking Sts expression to S. aureus infection. Herein, we demonstrate that Sts -/- animals are significantly resistant to lethal intravenous doses of S. aureus strain USA300. Resistance is characterized by significantly enhanced survival and accelerated bacterial clearance in multiple peripheral organs. Infected Sts -/- animals do not display increased levels of cytokines TNFα, IFNγ, and IL-6 in the spleen, liver, and kidney during the early stages of the infection, suggesting that a heightened pro-inflammatory response does not underlie the resistance phenotype. In vivo ablation of mononuclear phagocytes compromises the Sts -/- enhanced CFU clearance phenotype. Additionally, Sts -/- bone marrow-derived macrophages demonstrate significantly enhanced restriction of intracellular S. aureus following ex vivo infection. These results reveal the Sts enzymes to be critical regulators of host immunity to a virulent Gram-positive pathogen and identify them as therapeutic targets for optimizing host anti-microbial responses.
Collapse
Affiliation(s)
- Anika Zaman
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, New York, USA
- Graduate Program in Molecular and Cellular Pharmacology, Stony Brook University, Stony Brook, New York, USA
| | - Elizabeth Diago Navarro
- Division of Infectious Diseases, Department of Medicine, Stony Brook University, Stony Brook, New York, USA
| | - Bettina C. Fries
- Graduate Program in Molecular and Cellular Pharmacology, Stony Brook University, Stony Brook, New York, USA
- Division of Infectious Diseases, Department of Medicine, Stony Brook University, Stony Brook, New York, USA
- Veterans Administration Medical Center, Northport, New York, USA
| | - Hwan Keun Kim
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, New York, USA
- Center for Infectious Diseases, Stony Brook University, Stony Brook, New York, USA
| | - Nick Carpino
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, New York, USA
| |
Collapse
|
4
|
Tsygankov AY. TULA Proteins in Men, Mice, Hens, and Lice: Welcome to the Family. Int J Mol Sci 2023; 24:ijms24119126. [PMID: 37298079 DOI: 10.3390/ijms24119126] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 05/16/2023] [Accepted: 05/18/2023] [Indexed: 06/12/2023] Open
Abstract
The two members of the UBASH3/STS/TULA protein family have been shown to critically regulate key biological functions, including immunity and hemostasis, in mammalian biological systems. Negative regulation of signaling through immune receptor tyrosine-based activation motif (ITAM)- and hemITAM-bearing receptors mediated by Syk-family protein tyrosine kinases appears to be a major molecular mechanism of the down-regulatory effect of TULA-family proteins, which possess protein tyrosine phosphatase (PTP) activity. However, these proteins are likely to carry out some PTP-independent functions as well. Whereas the effects of TULA-family proteins overlap, their characteristics and their individual contributions to cellular regulation also demonstrate clearly distinct features. Protein structure, enzymatic activity, molecular mechanisms of regulation, and biological functions of TULA-family proteins are discussed in this review. In particular, the usefulness of the comparative analysis of TULA proteins in various metazoan taxa, for identifying potential roles of TULA-family proteins outside of their functions already established in mammalian systems, is examined.
Collapse
Affiliation(s)
- Alexander Y Tsygankov
- Sol Sherry Thrombosis Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, PA 19140, USA
| |
Collapse
|
5
|
Zaman A, French JB, Carpino N. The Sts Proteins: Modulators of Host Immunity. Int J Mol Sci 2023; 24:8834. [PMID: 37240179 PMCID: PMC10218301 DOI: 10.3390/ijms24108834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 05/08/2023] [Accepted: 05/10/2023] [Indexed: 05/28/2023] Open
Abstract
The suppressor of TCR signaling (Sts) proteins, Sts-1 and Sts-2, are a pair of closely related signaling molecules that belong to the histidine phosphatase (HP) family of enzymes by virtue of an evolutionarily conserved C-terminal phosphatase domain. HPs derive their name from a conserved histidine that is important for catalytic activity and the current evidence indicates that the Sts HP domain plays a critical functional role. Sts-1HP has been shown to possess a readily measurable protein tyrosine phosphatase activity that regulates a number of important tyrosine-kinase-mediated signaling pathways. The in vitro catalytic activity of Sts-2HP is significantly lower than that of Sts-1HP, and its signaling role is less characterized. The highly conserved unique structure of the Sts proteins, in which additional domains, including one that exhibits a novel phosphodiesterase activity, are juxtaposed together with the phosphatase domain, suggesting that Sts-1 and -2 occupy a specialized intracellular signaling niche. To date, the analysis of Sts function has centered predominately around the role of Sts-1 and -2 in regulating host immunity and other responses associated with cells of hematopoietic origin. This includes their negative regulatory role in T cells, platelets, mast cells and other cell types, as well as their less defined roles in regulating host responses to microbial infection. Regarding the latter, the use of a mouse model lacking Sts expression has been used to demonstrate that Sts contributes non-redundantly to the regulation of host immunity toward a fungal pathogen (C. albicans) and a Gram-negative bacterial pathogen (F. tularensis). In particular, Sts-/- animals demonstrate significant resistance to lethal infections of both pathogens, a phenotype that is correlated with some heightened anti-microbial responses of phagocytes derived from mutant mice. Altogether, the past several years have seen steady progress in our understanding of Sts biology.
Collapse
Affiliation(s)
- Anika Zaman
- Graduate Program in Molecular and Cellular Pharmacology, Stony Brook University, Stony Brook, NY 11794, USA;
| | - Jarrod B. French
- Hormel Institute, University of Minnesota, 801 16th Ave NE, Austin, MN 55912, USA;
| | - Nick Carpino
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, NY 11794, USA
| |
Collapse
|
6
|
Parashar K, Carpino N. A role for the Sts phosphatases in negatively regulating IFNγ-mediated production of nitric oxide in monocytes. IMMUNITY INFLAMMATION AND DISEASE 2020; 8:523-533. [PMID: 32841534 PMCID: PMC7654413 DOI: 10.1002/iid3.336] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 07/01/2020] [Accepted: 07/20/2020] [Indexed: 12/17/2022]
Abstract
Introduction The atypical Sts phosphatases negatively regulate signaling pathways in diverse immune cell types, with two of their molecular targets being the related kinases Syk and Zap‐70. Mice lacking Sts expression (Sts−/−) are resistant to infection by the live vaccine strain (LVS) of Francisella tularensis. Although the mechanisms underlying the enhanced resistance of Sts−/− mice have not been definitively established, Sts−/− bone marrow‐derived monocytes (BMMs) demonstrate greater clearance of intracellular LVS following ex vivo infection, relative to wild type cells. To determine how the Sts proteins regulate monocyte bactericidal properties, we analyzed responses of infected cells. Methods Monocyte bacterial clearance was assayed using ex vivo coculture infections followed by colony‐forming unit analysis of intracellular bacteria. Levels of gene expression were quantified by quantitative reverse‐transcription polymerase chain reaction, levels of Nos2 protein levels were quantified by Western blot analysis, and levels of nitric oxide (NO) were quantified directly using the Griess reagent. We characterized monocyte cytokine production via enzyme‐linked immunosorbent assay. Results We demonstrate that Sts−/− monocyte cultures produce elevated levels of interferon‐γ (IFNγ) after infection, relative to wild type cultures. Sts−/− monocytes also demonstrate heightened responsiveness to IFNγ. Specifically, Sts−/− monocytes produce elevated levels of antimicrobial NO following IFNγ stimulation, and this NO plays an important role in LVS restriction. Additional IFNγ‐stimulated genes, including Ip10 and members of the Gbp gene family, also display heightened upregulation in Sts−/− cells. Both Sts‐1 and Sts‐2 contribute to the regulation of NO production, as evidenced by the responses of monocytes lacking each phosphatase individually. Finally, we demonstrate that the elevated production of IFNγ‐induced NO in Sts−/− monocytes is abrogated following chemical inhibition of Syk kinase. Conclusion Our results indicate a novel role for the Sts enzymes in regulating monocyte antibacterial responses downstream of IFNγ.
Collapse
Affiliation(s)
- Kaustubh Parashar
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, New York
| | - Nicholas Carpino
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, New York
| |
Collapse
|
7
|
Yin Y, Frank D, Zhou W, Kaur N, French JB, Carpino N. An unexpected 2-histidine phosphoesterase activity of suppressor of T-cell receptor signaling protein 1 contributes to the suppression of cell signaling. J Biol Chem 2020; 295:8514-8523. [PMID: 32371395 DOI: 10.1074/jbc.ra120.013482] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 04/30/2020] [Indexed: 11/06/2022] Open
Abstract
The suppressor of T-cell receptor (TCR) signaling (Sts) proteins Sts-1 and Sts-2 suppress receptor-mediated signaling pathways in various immune cells, including the TCR pathway in T cells and the Dectin-1 signaling pathway in phagocytes. As multidomain enzymes, they contain an N-terminal ubiquitin-association domain, a central Src homology 3 domain, and a C-terminal histidine phosphatase domain. Recently, a 2-histidine (2H) phosphoesterase motif was identified within the N-terminal portion of Sts. The 2H phosphoesterase motif defines an evolutionarily ancient protein domain present in several enzymes that hydrolyze cyclic phosphate bonds on different substrates, including cyclic nucleotides. It is characterized by two invariant histidine residues that play a critical role in catalytic activity. Consistent with its assignment as a phosphoesterase, we demonstrate here that the Sts-1 2H phosphoesterase domain displays catalytic, saturable phosphodiesterase activity toward the dinucleotide 2',3'-cyclic NADP. The enzyme exhibited a high degree of substrate specificity and selectively generated the 3'-nucleotide as the sole product. Sts-1 also had phosphodiesterase catalytic activity toward a 5-mer RNA oligonucleotide containing a 2',3'-cyclic phosphate group at its 3' terminus. To investigate the functional significance of Sts-1 2H phosphoesterase activity, we generated His-to-Ala variants and examined their ability to negatively regulate cellular signaling pathways. Substitution of either conserved histidine compromised the ability of Sts-1 to suppress signaling pathways downstream of both the TCR and the Dectin-1 receptor. Our results identify a heretofore unknown cellular enzyme activity associated with Sts-1 and indicate that this catalytic activity is linked to specific cell-signaling outcomes.
Collapse
Affiliation(s)
- Yue Yin
- Department of Chemistry, Stony Brook University, Stony Brook, New York, USA
| | - David Frank
- Department of Microbiology and Immunology, Stony Brook University Medical Center, Stony Brook, New York, USA
| | - Weijie Zhou
- Department of Chemistry, Stony Brook University, Stony Brook, New York, USA
| | - Neena Kaur
- Department of Microbiology and Immunology, Stony Brook University Medical Center, Stony Brook, New York, USA
| | - Jarrod B French
- Department of Chemistry, Stony Brook University, Stony Brook, New York, USA .,Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, New York, USA
| | - Nick Carpino
- Department of Microbiology and Immunology, Stony Brook University Medical Center, Stony Brook, New York, USA
| |
Collapse
|
8
|
Zhou W, Yin Y, Smith E, Chou J, Shumate J, Scampavia L, Spicer TP, Carpino N, French JB. Discovery and Characterization of Two Classes of Selective Inhibitors of the Suppressor of the TCR Signaling Family of Proteins. ACS Infect Dis 2019; 5:250-259. [PMID: 30485744 DOI: 10.1021/acsinfecdis.8b00238] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The suppressor of T-cell receptor signaling (Sts) proteins, Sts-1, has recently emerged as a potential immunostimulatory target for drug development. Genetic inactivation of the Sts proteins dramatically increases host survival of systemic infection and leads to improved pathogen clearance. The protein tyrosine phosphatase (PTP) activity of these proteins arises from a C-terminal 2-histidine phosphatase (HP) domain. To identify new inhibitors of the HP activity of Sts-1, we miniaturized a phosphatase assay to a 1536-well format and conducted a 20 580 compound screen. Among the hits were two classes of structurally related compounds, tetracycline variants and sulfonated azo dyes. These hits had low micromolar to nanomolar IC50 values. Orthogonal screening confirmed the validity of these inhibitors and demonstrated that both act competitively on Sts-1 phosphatase activity. When tested on other PTPs, PTP1B and SHP1, it was found that the tetracycline PTP1B, SHP1, the tetracycline variant (doxycycline), and the sulfonated azo dye (Congo red) are selective inhibitors of Sts-1HP, with selectivity indices ranging from 19 to as high as 200. The planar polyaromatic moieties present in both classes of compounds suggested a common binding mode. The mutation of either tryptophan 494 or tyrosine 596, located near the active site of the protein, reduced the Ki of the inhibitors from 3- to 18-fold, indicating that these residues may help to promote the binding of substrates with aromatic groups. This work provides new insights into substrate selectivity mechanisms and describes two classes of compounds that can serve as probes of function or as a basis for future drug discovery.
Collapse
Affiliation(s)
| | | | - Emery Smith
- Department of Molecular Medicine, Scripps Research Molecular Screening Center, Scripps Research, 130 Scripps Way, Jupiter, Florida 33458, United States
| | | | - Justin Shumate
- Department of Molecular Medicine, Scripps Research Molecular Screening Center, Scripps Research, 130 Scripps Way, Jupiter, Florida 33458, United States
| | - Louis Scampavia
- Department of Molecular Medicine, Scripps Research Molecular Screening Center, Scripps Research, 130 Scripps Way, Jupiter, Florida 33458, United States
| | - Timothy P. Spicer
- Department of Molecular Medicine, Scripps Research Molecular Screening Center, Scripps Research, 130 Scripps Way, Jupiter, Florida 33458, United States
| | | | | |
Collapse
|
9
|
In Vivo Intradermal Delivery of Bacteria by Using Microneedle Arrays. Infect Immun 2018; 86:IAI.00406-18. [PMID: 29986891 DOI: 10.1128/iai.00406-18] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 06/19/2018] [Indexed: 01/23/2023] Open
Abstract
Infectious diseases propagated by arthropod vectors, such as tularemia, are commonly initiated via dermal infection of the skin. However, due to the technical difficulties in achieving accurate and reproducible dermal deposition, intradermal models are less commonly used. To overcome these limitations, we used microneedle arrays (MNAs), which are micron-scale polymeric structures, to temporarily disrupt the barrier function of the skin and deliver a bacterial inoculum directly to the dermis of an animal. MNAs increase reliability by eliminating leakage of the inoculum or blood from the injection site, thereby providing a biologically relevant model for arthropod-initiated disease. Here, we validate the use of MNAs as a means to induce intradermal infection using a murine model of tularemia initiated by Francisella novicida We demonstrate targeted delivery of the MNA bolus to the dermal layer of the skin, which subsequently led to innate immune cell infiltration. Additionally, F. novicida-coated MNAs were used to achieve lethality in a dose-dependent manner in C57BL/6 mice. The immune profile of infected mice mirrored that of established F. novicida infection models, consisting of markedly increased serum levels of interleukin-6 and keratinocyte chemoattractant, splenic T-cell depletion, and an increase in splenic granulocytes, together confirming that MNAs can be used to reproducibly induce tularemia-like pathogenesis in mice. When MNAs were used to immunize mice using an attenuated F. novicida mutant (F. novicida ΔlpxD1), all immunized mice survived a lethal subcutaneous challenge. Thus, MNAs can be used to effectively deliver viable bacteria in vivo and provide a novel avenue to study intradermally induced microbial diseases in animal models.
Collapse
|
10
|
Tsygankov AY. TULA-family proteins: Jacks of many trades and then some. J Cell Physiol 2018; 234:274-288. [PMID: 30076707 DOI: 10.1002/jcp.26890] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 06/13/2018] [Indexed: 12/17/2022]
Abstract
UBASH3/STS/TULA is a novel two-member family, which exerts several key regulatory effects in multiple cell types. UBASH3B/STS-1/TULA-2 is a highly active protein tyrosine phosphatase; its major target appears to be a specific regulatory site of protein tyrosine kinases of the Syk family, dephosphorylation of which inhibits Syk and Zap-70 kinases and suppresses receptor signaling mediated by these kinases. UBASH3A/STS-2/TULA exhibits substantial homology to UBASH3B/STS-1/TULA-2, but possesses only a small fraction of phosphatase activity of UBASH3B/STS-1/TULA-2, and thus, its regulatory effect may be based also on the phosphatase-independent mechanisms. Critical physiologic effects of these proteins have been demonstrated in T lymphocytes, platelets, stem cells, and other important cell types. These proteins have also been shown to play a key role in such pathologic conditions as autoimmunity, cancer, and thrombosis. The review focuses on the recent studies of this important family of cellular regulators.
Collapse
Affiliation(s)
- Alexander Y Tsygankov
- Department of Microbiology and Immunology, Fels Institute for Cancer Research and Molecular Biology and Sol Sherry Thrombosis Center, Temple University School of Medicine, Philadelphia, Pennsylvania
| |
Collapse
|
11
|
Carpino N, Naseem S, Frank DM, Konopka JB. Modulating Host Signaling Pathways to Promote Resistance to Infection by Candida albicans. Front Cell Infect Microbiol 2017; 7:481. [PMID: 29201860 PMCID: PMC5696602 DOI: 10.3389/fcimb.2017.00481] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 11/06/2017] [Indexed: 12/29/2022] Open
Abstract
Candida albicans is a common human fungal pathogen capable of causing serious systemic infections that can progress to become lethal. Current therapeutic approaches have limited effectiveness, especially once a systemic infection is established, in part due to the lack of an effective immune response. Boosting the immune response to C. albicans has been the goal of immunotherapy, but it has to be done selectively to prevent deleterious hyperinflammation (sepsis). Although an efficient inflammatory response is necessary to fight infection, the typical response to C. albicans results in collateral damage to tissues thereby exacerbating the pathological effects of infection. For this reason, identifying specific ways of modulating the immune system holds promise for development of new improved therapeutic approaches. This review will focus on recent studies that provide insight using mutant strains of mice that are more resistant to bloodstream infection by C. albicans. These mice are deficient in signal transduction proteins including the Jnk1 MAP kinase, the Cbl-b E3 ubiquitin ligase, or the Sts phosphatases. Interestingly, the mutant mice display a different response to C. albicans that results in faster clearance of infection without hyper-inflammation and collateral damage. A common underlying theme between the resistant mouse strains is loss of negative regulatory proteins that are known to restrain activation of cell surface receptor-initiated signaling cascades. Understanding the cellular and molecular mechanisms that promote resistance to C. albicans in mice will help to identify new approaches for improving antifungal therapy.
Collapse
Affiliation(s)
- Nick Carpino
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, United States
| | - Shamoon Naseem
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, United States
| | - David M Frank
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, United States
| | - James B Konopka
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, United States
| |
Collapse
|