Background: Postdoctoral work in the Department of Biochemistry, University of Dundee (1994-1996); MRC Laboratory of Molecular Cell Biology, University College London (1997-1998); Cambridge Institute for Medical Research, University of Cambridge (1999-2002). In September 2002 I was appointed as a Lecturer at the University of Leeds
Contact: Garstang 9.58, +44(0) 113 34 33030,
You can read more about Dr Hewitt's interests here:
CELL BIOLOGY OF AMYLOID DISEASE & THE IMMUNE SYSTEM
(I) Cell biology of amyloid disease
Amyloid formation is associated with a spectrum of human diseases, including Alzheimer’s disease, Huntington’s disease, type II diabetes and dialysis-related amyloidosis.In these diseases proteins and peptides aggregate into insoluble fibrils that accumulate in macroscopic amyloid plaques. Amyloid deposition can result in cell death and tissue destruction, but the precise culprits and mechanisms of toxicity are poorly understood. Numerous studies suggest that oligomeric assembly intermediates are the major cytotoxic species associated with amyloid formation, which has led to the notion that amyloid fibrils are an inert end product of amyloid assembly. Our data suggest that the situation is more complex and that fibrils can also be cytotoxic, but that this is dependent on fibril length. Using β2-microglobulin, which forms amyloid in dialysis-related amyloidosis, we have shown that fragmentation of micron-length fibrils produces shorter nanoscale fibrils that resemble those formed early in amyloid assembly reactions. These nanoscale fibrils are readily internalized and sorted to lysosomes. Crucially nanoscale fibrils inhibit lysosome proteolysis and cause the missorting of lysosomal proteins. These data demonstrate that fibril length by determining the accessibility of intracellular compartments may be a key factor in amyloid disorders. In our ongoing work we are investigating how nanoscale β2-microglobulin amyloid fibrils disrupt lysosome function and trafficking and whether other disease-associated amyloid fibrils, such as those formed in Alzheimer’s and Parkinson’s, exhibit length-dependent toxicity by disrupting the endolysosomal pathway.
Tipping KW, Karamanos TK, Jakhria T, Iadanza MG, Goodchild SC, Tuma R, Ranson NA, Hewitt EW, Radford SE. (2015). pH-induced molecular shedding drives the formation of amyloid fibril-derived oligomers. Proc Natl Acad Sci U S A 112: 5691-6.
Jakhria T, Hellewell AL, Porter MY, Jackson M, Tipping KW, Xue WF Radford SE, Hewitt EW (2014). β2-microglobulin amyloid fibrils are nanoparticles that disrupt?lysosomal membrane protein trafficking and inhibit protein degradation by lysosomes. J. Biol. Chem. 289:35781-94
Goodchild SC, Sheynis T, Thompson R, Tipping KW, Xue WF, Ranson NA, Beales PA, Hewitt EW, Radford SE. (2014) β2-Microglobulin amyloid fibril-induced membrane disruption is enhanced by endosomal lipids and acidic pH. PLoS One. 9, e104492.
Sheynis T, Friediger A, Xue WF, Hellewell AL, Tipping KW, Hewitt EW, Radford SE, Jelinek R. (2013) Aggregation modulators interfere with membrane interactions of β2-microglobulin fibrils. Biophys J. 105, 745-55
Milanesi L, Sheynis T, Xue WF, Orlova EV, Hellewell AL, Jelinek R, Hewitt EW, Radford SE, Saibil HR. (2012). Direct three-dimensional visualization of membrane disruption by amyloid fibrils. Proc Natl Acad Sci USA. 109, 20455-60.
Porter MY, Routledge KE, Radford SE, Hewitt EW (2011). Characterization of the response of primary cells relevant to dialysis-related amyloidosis to β2-microglobulin monomer and fibrils PLoS One. 6, e27353.
Woods LA, Platt GW, Hellewell AL, Hewitt EW, Homans SW, Ashcroft AE, Radford SE (2011) Ligand binding to distinct states diverts aggregation of an amyloid-forming protein. Nat Chem Biol. 7, 730-9
Xue WF, Hellewell AL, Gosal, WS Homans, SW, Hewitt EW, Radford, SE (2009) Fibril fragmentation enhances amyloid toxicity. J. Biol Chem. 284, 34272-8
Morten, IJ, Gosal, WS, Radford, SE and Hewitt, EW. (2007) Investigation into the role of macrophages in the formation and degradation of beta-2-microglobulin amyloid fibrils. J Biol Chem. 282, 29691-700.
Borysik AJ, Morten IJ, Radford SE and Hewitt EW. (2007) Specific glycosaminoglycans promote unseeded amyloid formation from beta-2-microglobulin under physiological conditions. Kidney Int 72, 174-81.
(2) Cell biology of natural killer (NK) cells: how do NK cells kill?
Natural killer (NK) cells are specialised lymphocytes that eliminate virally infected and transformed cells. NK cells play a complementary role to CTLs, as they can recognise cells that have lost expression of MHC class I molecules. NK cells store cytotoxic molecules (perforin, granzymes and Fas ligand) in their secretory lysosomes and recognition of an infected or transformed cell triggers the release of these cytotoxic molecules in order to kill the target cell. Yet, despite the pivotal role the secretory lysosome plays in NK cell function, how this organelle docks and fuses with the plasma membrane to facilitate release of cytotoxic molecules is poorly understood. We are, therefore, using a combination of cell biological and proteomic techniques with which to identify the exocytic machinery and to dissect the role that these proteins play in secretory lysosome exocytosis and target cell killing.
Hellewell AL, Foresti O, Gover N, Porter MY, Hewitt EW. (2014). Analysis of familial hemophagocytic lymphohistiocytosis type 4 (FHL-4) mutant proteins reveals that S-acylation is required for the function of syntaxin 11 in natural killer cells. PLoS One. 9, e98900.
Topham, NJ, and Hewitt, EW (2009) Natural killer cell cytotoxicity: how do they pull the trigger? Immunology. 128, 7-15.
Casey, T.M., Meade, J.L. and Hewitt, E.W. (2007). Organelle proteomics: Identification of the exocytic machinery associated with the natural killer cell secretory lysosome. Mol Cell Proteomics. 6, 767-80.
MICR2120 - Cell Biology of Disease
BIOC2303 - Intermediate Biochemistry: Skills
BIOC3111/12/BIOL3112/MICR3120/BIOL5146M B - ATU - Antiviral Immunity
BIOC3160 - Laboratory/Literature/Computing Research Project
BIOC3221/22/BIOL3210 b - ATU - Folding & Diseases
BIOL2211 - Human Diseases
BIOL2301 - Intermediate Skills for Biological Sciences
BIOL2301/03/05/MICR2320 - Skills for Biol Sci, Biosciences and Microbiology
BIOL3305 - Advanced Skills in the Biosciences
BIOL3306 - Biological Sciences Research Project
BIOL3398 - Research Tools and Applications
BIOL3399 - Extended Research Project Preparation
BIOL3400 - Skills in the Cell Biology of Human Disease
BIOL5372M - Advanced Biomolecular Technologies
BIOW5901X - Foundation module
MICR1220 - Introduction to Immunology
MICR2120 - Cell Biology of Disease
MICR2120/BIOC2301 - Integrated Biochemistry/Medical Bacteriology
MICR2121 - Molecular Virology
MICR2221 - Medical Immunology
MICR2320/MICR3343 - Skills for Microbiology i
MICR3325 - Skills for Microbiologists 3
MICR3343 - Skills for Microbiology in Relation to Medicine
Member of Undergraduate School Taught Student Education Committee (Programme Manager: Microbiology)
Centre membership: The Astbury Centre for Structural Molecular Biology
Chi Chau (Primary supervisor) 50% FTE
Michael Davies (Primary supervisor) 50% FTE
Atenas Posada Borbon (Primary supervisor) 50% FTE
Adrienne Seitz (Co-supervisor) 33% FTE
Lauren Yarrow (Co-supervisor) 25% FTE
Pashley CL, Hewitt EW, Radford SE Comparison of the aggregation of homologousβ<inf>2</inf>-microglobulin variants reveals protein solubility as a key determinant of amyloid formation Journal of Molecular Biology 428 631-643, 2016
Tipping KW, Karamanos TK, Jakhria T, Iadanza MG, Goodchild SC, Tuma R, Ranson NA, Hewitt EW, Radford SE pH-induced molecular shedding drives the formation of amyloid fibril-derived oligomers Proceedings of the National Academy of Sciences of the United States of America 112 E5691-E5696, 2015
Tipping KW, van Oosten-Hawle P, Hewitt EW, Radford SE Amyloid Fibres: Inert End-Stage Aggregates or Key Players in Disease? Trends in Biochemical Sciences 40 719-727, 2015
Jakhria T, Hellewell AL, Porter MY, Jackson MP, Tipping KW, Xue WF, Radford SE, Hewitt EW β2-microglobulin amyloid fibrils are nanoparticles that disrupt lysosomal membrane protein trafficking and inhibit protein degradation by lysosomes Journal of Biological Chemistry 289 35781-35794, 2014
Cherukuri A, Rothstein DM, Clark B, Carter CR, Davison A, Hernandez-Fuentes M, Hewitt E, Salama AD, Baker RJ Immunologic human renal allograft injury associates with an altered IL-10/TNF-α expression ratio in regulatory B cells. J Am Soc Nephrol 25 1575-1585, 2014
Goodchild SC, Sheynis T, Thompson R, Tipping KW, Xue W-F, Ranson NA, Beales PA, Hewitt EW, Radford SE β2-Microglobulin amyloid fibril-induced membrane disruption is enhanced by endosomal lipids and acidic pH. PLoS One 9 e104492-, 2014
Hellewell AL, Foresti O, Gover N, Porter MY, Hewitt EW Analysis of familial hemophagocytic lymphohistiocytosis type 4 (FHL-4) mutant proteins reveals that S-acylation is required for the function of syntaxin 11 in natural killer cells. PLoS One 9 e98900-, 2014
Sheynis T, Friediger A, Xue W-F, Hellewell AL, Tipping KW, Hewitt EW, Radford SE, Jelinek R Aggregation modulators interfere with membrane interactions ofβ2-microglobulin fibrils. Biophys J 105 745-755, 2013
Cherukuri A, Salama AD, Carter C, Smalle N, McCurtin R, Hewitt EW, Hernandez-Fuentes M, Clark B, Baker RJ An analysis of lymphocyte phenotype after steroid avoidance with either alemtuzumab or basiliximab induction in renal transplantation. Am J Transplant 12 919-931, 2012
Woods LA, Platt GW, Hellewell AL, Hewitt EW, Homans SW, Ashcroft AE, Radford SE Ligand binding to distinct states diverts aggregation of an amyloid-forming protein. Nat Chem Biol 7 730-739, 2011
Porter MY, Routledge KE, Radford SE, Hewitt EW Characterization of the response of primary cells relevant to dialysis-related amyloidosis toβ2-microglobulin monomer and fibrils. PLoS One 6 e27353-, 2011
Xue WF, Hellewell AL, Gosal WS, Homans SW, Hewitt EW, Radford SE Fibril Fragmentation Enhances Amyloid Cytotoxicity J BIOL CHEM 284 34272-34282, 2009
Topham NJ, Hewitt EW Natural killer cell cytotoxicity: how do they pull the trigger? IMMUNOLOGY 128 7-15, 2009
Dugan GE, Hewitt EW Dependence of the localization and function of the human cytomegalovirus protein US6 on the transporter associated with antigen processing J GEN VIROL 90 2234-2238, 2009
Gould F, Harrison SM, Hewitt EW, Whitehouse A Kaposi's Sarcoma-Associated Herpesvirus RTA Promotes Degradation of the Hey1 Repressor Protein through the Ubiquitin Proteasome Pathway J VIROL 83 6727-6738, 2009
Dugan GE, Hewitt EW Structural and functional dissection of the human cytomegalovirus immune evasion protein US6 J VIROL 82 3271-3282, 2008
Borysik AJ, Morten IJ, Radford SE, Hewitt EW Specific glycosaminoglycans promote unseeded amyloid formation from beta(2)-microglobulin under physiological conditions KIDNEY INT 72 174-181, 2007
Casey TM, Meade JL, Hewitt EW Organelle proteomics: identification of the exocytic machinery associated with the natural killer cell secretory lysosome. Mol Cell Proteomics 6 767-780, 2007
Myers SL, Jones S, Jahn TR, Morten IJ, Tennent GA, Hewitt EW, Radford SE A systematic study of the effect of physiological factors on beta2-microglobulin amyloid formation at neutral pH. Biochemistry 45 2311-2321, 2006
Hewitt EW, Dugan G Virus subversion of protective immunity Current allergy and asthma reports 4 365-370, 2004
Hewitt EW The MHC class I antigen presentation pathway: strategies for viral immune evasion IMMUNOLOGY 110 163-169, 2003
Hewitt EW, Lehner PJ The ABC-transporter signature motif is required for peptide translocation but not peptide binding by TAP European Journal of Immunology 33 422-427, 2003
Hewitt EW, Duncan L, Mufti D, Baker JS, Stevenson PG, Lehner PJ Ubiquitylation of MHC class I by the K3 viral protein signals internalization and TSG101-dependent degradation EMBO Journal 21 2418-2429, 2002
van Endert PM, Saveanu L, Hewitt EW, Lehner PJ Powering the peptide pump: TAP crosstalk with energetic nucleotides Trends in Biochemical Sciences 27 454-461, 2002
Karttunen J, Lehner PJ, Sen Gupta S, Hewitt EW, Cresswell P Distinct functions and cooperative interaction of the subunits of the transporter associated with antigen processing (TAP) Proceedings of the National Academy of Sciences of the United States of America 98 7431-7436, 2001
Hewitt EW, Sen Gupta S, Lehner PJ The human cytomegalovirus gene product US6 inhibits ATP binding by TAP EMBO Journal 20 387-396, 2001
Lehner PJ, Hewitt EW, Römisch K Antigen presentation: peptides and proteins scramble for the exit. Curr Biol 10 R839-R842, 2000
Emsley P, Fotinou C, Black I, Fairweather NF, Charles IG, Watts C, Hewitt E, Isaacs NW The structures of the H-C fragment of tetanus toxin with carbohydrate subunit complexes provide insight into ganglioside binding J BIOL CHEM 275 8889-8894, 2000
Blagoveshchenskaya AD, Hewitt EW, Cutler DF Di-leucine signals mediate targeting of tyrosinase and synaptotagmin to synaptic-like microvesicles within PC12 cells. Mol Biol Cell 10 3979-3990, 1999
Blagoveshchenskaya AD, Hewitt EW, Cutler DF A complex web of signal-dependent trafficking underlies the triorganellar distribution of P-selectin in neuroendocrine PC12 cells. J Cell Biol 145 1419-1433, 1999
Manoury B, Hewitt EW, Morrice N, Dando PM, Barrett AJ, Watts C An asparaginyl endopeptidase processes a microbial antigen for class II MHC presentation. Nature 396 695-699, 1998
Blagoveshchenskaya AD, Hewitt EW, Cutler DF A balance of opposing signals within the cytoplasmic tail controls the lysosomal targeting of P-selectin. J Biol Chem 273 27896-27903, 1998
Regnacq M, Hewitt E, Allen J, Rosamond J, Stirling CJ Deletion analysis of yeast Sec65p reveals a central domain that is sufficient for function in vivo. Mol Microbiol 29 753-762, 1998
Watts C, Antoniou A, Manoury B, Hewitt EW, Mckay LM, Grayson L, Fairweather NF, Emsley P, Isaacs N, Simitsek PD Modulation by epitope-specific antibodies of class II MHC-restricted presentation of the tetanus toxin antigen. Immunol Rev 164 11-16, 1998
Manoury B, Hewitt EW, Morrice N, Dando PM, Barret AJ, Watts C A key role for aspariginyl endopeptidase in processing and class II MHC presentation of a microbial antigen Nature 396 695-699, 1998
Hewitt EW, Treumann A, Morrice N, Tatnell PJ, Kay J, Watts C Natural processing sites for human cathepsin E and cathepsin D in tetanus toxin - Implications for T cell epitope generation J IMMUNOL 159 4693-4699, 1997
Chen JM, Dando PM, Rawlings ND, Brown MA, Young NE, Stevens RA, Hewitt E, Watts C, Barrett AJ Cloning, isolation, and characterization of mammalian legumain, an asparaginyl endopeptidase J BIOL CHEM 272 8090-8098, 1997
Xue W-F, Hellewell AL, Hewitt EW, Radford SE Fibril fragmentation in amyloid assembly and cytotoxicity: when size matters. Prion 4 20-25, 2010
Hewitt EW, Tao JX, Strasser JE, Cutler DF, Dean GE Synaptotagmin I-delta C2B. A novel synaptotagim isoform with a single C2 domain in the bovine adrenal medulla. Biochimica et Biophysica Acta 1561 76-90, 2002
Morten IJ, Hewitt EW, Radford SE Protein Misfolding, b2-microglobulin and dialysis-related amyloidosis In Aggregation and Conformational Diseases ,