Dr Louisa Ashby

Contact Details
- Phone
- +64 3 378 6223
- louisa.ashby@otago.ac.nz
University Links
- Position
- Senior Research Fellow
- Department
- Department of Pathology and Biomedical Science (Christchurch)
- Qualifications
- PhD
- Research summary
- Free radical research
Research
My research interest is focused on the biochemistry of the neutrophil, and in particular the enzymology of myeloperoxidase. This enzyme kills microbes by generating chlorine bleach, but during inflammation it can also damage healthy tissue.
We are interested in the oxidation chemistry of myeloperoxidase in its microbicidal activity, and how to effectively inhibit the enzyme from causing oxidative stress in disease.
Publications
Paumann-Page, M., Ashby, L. V., Khalilova, I., Magon, N. J., Hofbauer, S., Paton, L. N., … Kettle, A. J. (2023). Hypochlorous acid inactivates myeloperoxidase inside phagocytosing neutrophils. Redox Biochemistry & Chemistry, 5-6, 100008. doi: 10.1016/j.rbc.2023.100008
Kettle, A. J., Ashby, L. V., Winterbourn, C. C., & Dickerhof, N. (2023). Superoxide: The enigmatic chemical chameleon in neutrophil biology [Invited review]. Immunological Reviews. Advance online publication. doi: 10.1111/imr.13183
Ashby, L. V., Springer, R., Loi, V. V., Antelmann, H., Hampton, M. B., Kettle, A. J., & Dickerhof, N. (2022). Oxidation of bacillithiol during killing of Staphylococcus aureus USA300 inside neutrophil phagosomes. Journal of Leukocyte Biology, 112, 591-605. doi: 10.1002/jlb.4hi1021-538rr
Königstorfer, A., Ashby, L. V., Bollar, G. E., Billiot, C. E., Gray, M. J., Jakob, U., Hampton, M. B., & Winterbourn, C. C. (2021). Induction of the reactive chlorine-responsive transcription factor RclR in Escherichia coli following ingestion by neutrophils. Pathogens & Disease, 79, ftaa079. doi: 10.1093/femspd/ftaa079
Magon, N. J., Parker, H. A., Ashby, L. V., Springer, R. J., & Hampton, M. B. (2020). Analysis of neutrophil bactericidal activity. In M. T. Quinn & F. R. DeLeo (Eds.), Neutrophil: Methods and protocols: Methods in molecular biology (Vol. 2087). (3rd ed.) (pp. 149-164). New York, NY: Humana Press. doi: 10.1007/978-1-0716-0154-9_12
Magon, N. J., Parker, H. A., Ashby, L. V., Springer, R. J., & Hampton, M. B. (2020). Analysis of neutrophil bactericidal activity. In M. T. Quinn & F. R. DeLeo (Eds.), Neutrophil: Methods and protocols: Methods in molecular biology (Vol. 2087). (3rd ed.) (pp. 149-164). New York, NY: Humana Press. doi: 10.1007/978-1-0716-0154-9_12
Chapter in Book - Research
Forbes, L. V., & Kettle, A. J. (2018). Myeloperoxidase: Unleashing the power of hydrogen peroxide. In M. C. M. Vissers, M. B. Hampton & A. J. Kettle (Eds.), Hydrogen peroxide metabolism in health and disease. (pp. 281-304). Boca Raton, FL: CRC Press.
Chapter in Book - Research
Paumann-Page, M., Ashby, L. V., Khalilova, I., Magon, N. J., Hofbauer, S., Paton, L. N., … Kettle, A. J. (2023). Hypochlorous acid inactivates myeloperoxidase inside phagocytosing neutrophils. Redox Biochemistry & Chemistry, 5-6, 100008. doi: 10.1016/j.rbc.2023.100008
Journal - Research Article
Ashby, L. V., Springer, R., Loi, V. V., Antelmann, H., Hampton, M. B., Kettle, A. J., & Dickerhof, N. (2022). Oxidation of bacillithiol during killing of Staphylococcus aureus USA300 inside neutrophil phagosomes. Journal of Leukocyte Biology, 112, 591-605. doi: 10.1002/jlb.4hi1021-538rr
Journal - Research Article
Königstorfer, A., Ashby, L. V., Bollar, G. E., Billiot, C. E., Gray, M. J., Jakob, U., Hampton, M. B., & Winterbourn, C. C. (2021). Induction of the reactive chlorine-responsive transcription factor RclR in Escherichia coli following ingestion by neutrophils. Pathogens & Disease, 79, ftaa079. doi: 10.1093/femspd/ftaa079
Journal - Research Article
Albrett, A. M., Ashby, L. V., Dickerhof, N., Kettle, A. J., & Winterbourn, C. C. (2018). Heterogeneity of hypochlorous acid production in individual neutrophil phagosomes revealed by a rhodamine-based probe. Journal of Biological Chemistry, 293(40), 15715-15724. doi: 10.1074/jbc.RA118.004789
Journal - Research Article
Coker, M. S., Forbes, L. V., Plowman-Holmes, M., Murdoch, D. R., Winterbourn, C. C., & Kettle, A. J. (2018). Interactions of staphyloxanthin and enterobactin with myeloperoxidase and reactive chlorine species. Archives of Biochemistry & Biophysics, 646, 80-89. doi: 10.1016/j.abb.2018.03.039
Journal - Research Article
Forbes, L. V., & Kettle, A. J. (2018). A multi-substrate assay for finding physiologically effective inhibitors of myeloperoxidase. Analytical Biochemistry, 544, 13-21. doi: 10.1016/j.ab.2017.12.022
Journal - Research Article
Turner, R., Brennan, S. O., Ashby, L. V., Dickerhof, N., Hamzah, M. R., Pearson, J. F., Stamp, L. K., & Kettle, A. J. (2018). Conjugation of urate-derived electrophiles to proteins during normal metabolism and inflammation. Journal of Biological Chemistry, 293(51), 19886-19898. doi: 10.1074/jbc.RA118.005237
Journal - Research Article
Kettle, A. J., Albrett, A. M., Chapman, A. L., Dickerhof, N., Forbes, L. V., Khalilova, I., & Turner, R. (2014). Measuring chlorine bleach in biology and medicine. Biochimica et Biophysica Acta: General Subjects, 1840(2), 781-793. doi: 10.1016/j.bbagen.2013.07.004
Journal - Research Article
Stamp, L. K., Turner, R., Khalilova, I. S., Zhang, M., Drake, J., Forbes, L. V., & Kettle, A. J. (2014). Myeloperoxidase and oxidation of uric acid in gout: Implications for the clinical consequences of hyperuricaemia. Rheumatology, 53(11), 1958-1965. doi: 10.1093/rheumatology/keu218
Journal - Research Article
Forbes, L. V., Sjögren, T., Auchère, F., Jenkins, D. W., Thong, B., Laughton, D., … Turner, R., … Kettle, A. J. (2013). Potent reversible inhibition of myeloperoxidase by aromatic hydromates. Journal of Biological Chemistry, 288(51), 36636-36647. doi: 10.1074/jbc.M113.507756
Journal - Research Article
Forbes, L. V., Furtmüller, P. G., Khalilova, I., Turner, R., Obinger, C., & Kettle, A. J. (2012). Isoniazid as a substrate and inhibitor of myeloperoxidase: Identification of amine adducts and the influence of superoxide dismutase on their formation. Biochemical Pharmacology, 84(7), 949-960. doi: 10.1016/j.bcp.2012.07.020
Journal - Research Article
Tidén, A.-K., Sjögren, T., Svensson, M., Bernlind, A., Senthilmohan, R., Auchère, F., … Forbes, L. V., Magon, N. J., Paton, L. N., Jameson, G. N. L., … Kettle, A. J. (2011). 2-Thioxanthines are mechanism-based inactivators of myeloperoxidase that block oxidative stress during inflammation. Journal of Biological Chemistry, 286(43), 37578-37589. doi: 10.1074/jbc.M111.266981
Journal - Research Article
Briggs, C., Kunka, S., Pennaneach, C., Forbes, L., & Machin, S. J. (2003). Performance evaluation of a new compact hematology analyzer, the Sysmex pocH-100i. Laboratory Hematology, 9(4), 225-233.
Journal - Research Article
Forbes, L. V., Gale, R. E., Pizzey, A., Pouwels, K., Nathwani, A., & Linch, D. C. (2002). An activating mutation in the transmembrane domain of the granulocyte colony-stimulating factor receptor in patients with acute myeloid leukemia. Oncogene, 21(39), 5981-5989. doi: 10.1038/sj.onc.1205767
Journal - Research Article
Forbes, L. V., Moss, S. J., & Segal, A. W. (1999). Phosphorylation of p67phox in the neutrophil occurs in the cytosol and is independent of p47phox. FEBS Letters, 449(2-3), 225-229. doi: 10.1016/S0014-5793(99)00444-5
Journal - Research Article
Forbes, L. V., Truong, O., Wientjes, F. B., Moss, S. J., & Segal, A. W. (1999). The major phosphorylation site of the NADPH oxidase component p67phox is Thr233. Biochemical Journal, 338(1), 99-105. doi: 10.1042/0264-6021:3380099
Journal - Research Article
Leino, L., Forbes, L., Segal, A., & Cockcroft, S. (1999). Reconstitution of GTPγS-induced NADPH oxidase activity in streptolysin-O-permeabilized neutrophils by specific cytosol fractions. Biochemical & Biophysical Research Communications, 265(1), 29-37. doi: 10.1006/bbrc.1999.1631
Journal - Research Article
Reeves, E. P., Dekker, L. V., Forbes, L. V., Wientjes, F. B., Grogan, A., Pappin, D. J. C., & Segal, A. W. (1999). Direct interaction between p47phox and protein kinase C: Evidence for targeting of protein kinase C by p47phox in neutrophils. Biochemical Journal, 344(3), 859-866. doi: 10.1042/0264-6021:3440859
Journal - Research Article
Abbott, W. G. H., Tan, P. L. J., Geursen, A., Fraser, J. D., Forbes, L., Simpson, I. J., … Skinner, M. A. (1998). TCRBV14S1 and rheumatoid arthritis revisited: Abnormalities in the percentage of transcribed TCRBV14S1 family genes in PBMC from rheumatoid arthritis patients. Scandinavian Journal of Rheumatology, 27, 68-75.
Journal - Research Article
Willis, J. A., Scott, R. S., Brown, L. J., Forbes, L. V., Schmidli, R. S., Zimmet, P. Z., … Rowley, M. J. (1996). Islet cell antibodies and antibodies against glutamic acid decarboxylase in newly diagnosed adult-onset diabetes mellitus. Diabetes Research & Clinical Practice, 33(2), 89-97. doi: 10.1016/0168-8227(96)01281-8
Journal - Research Article
Forbes, L. V., Scott, R. S., Brown, L. J., & Darlow, B. A. (1995). Immunogenetic, clinical and demographic characterization of childhood type 1 diabetes in New Zealand. Diabetes Care, 18(11), 1428-1433.
Journal - Research Article
Rudert, F., Visser, E., Forbes, L., Lindridge, E., Wang, L., & Watson, J. (1995). Identification of a silencer, enhancer, and basal promoter region in the human CD95 (Fas/APO-1) gene. DNA & Cell Biology, 14(11), 931-937.
Journal - Research Article
Rudert, F., Roos, M., Forbes, L., & Watson, J. (1994). Apoptosis in L929 cells expressing a CD40/Fas chimeric receptor: Dissociation of stimulatory from inhibitory death signalling functions. Biochemical & Biophysical Research Communications, 204(3), 1102-1110. doi: 10.1006/bbrc.1994.2576
Journal - Research Article
Forbes, L. V., Brown, L. J., & Scott, R. S. (1993). HLA-DQβ typing and non-Asp57 alleles in IDDM and nondiabetic subjects in New Zealand. Diabetes Care, 16(8), 1179-1183.
Journal - Research Article
Schmidli, R. S., Hagan, C., Scott, R. S., Livesey, J., & Forbes, L. V. (1993). Plasma proinsulin in recently diagnosed type 2 diabetes mellitus. Diabetes Research & Clinical Practice, 20(2), 133-138. doi: 10.1016/0168-8227(93)90007-R
Journal - Research Article
Scott, R. S., Brown, L. J., Darlow, B. A., Forbes, L. V., & Moore, M. P. (1992). Temporal variation in incidence of IDDM in Canterbury, New Zealand. Diabetes Care, 15(7), 895-899. doi: 10.2337/diacare.15.7.895
Journal - Research Article
Kettle, A. J., Ashby, L. V., Winterbourn, C. C., & Dickerhof, N. (2023). Superoxide: The enigmatic chemical chameleon in neutrophil biology [Invited review]. Immunological Reviews. Advance online publication. doi: 10.1111/imr.13183
Journal - Research Other
Ashby, L. V., Springer, R., Hampton, M. B., Kettle, A. J., & Winterbourn, C. C. (2020). Evaluating the bactericidal action of hypochlorous acid in culture media [Short communication]. Free Radical Biology & Medicine, 159, 119-124. doi: 10.1016/j.freeradbiomed.2020.07.033
Journal - Research Other
Carr, A., Pullar, J., Forbes, L., & Rosengrave, P. (2014). Working mothers are disadvantaged by limited funding for health research. New Zealand Medical Journal, 127(1398). Retrieved from http://www.nzma.org.nz/journal
Journal - Research Other