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Associate Professor Jacqui Keenan

Jacqui KeenanResearch Associate Professor 

MApplSci (1st Class Hons) PhD

Tel +64 3 364 0570
Email jacqui.keenan@otago.ac.nz

Jacqui is a Research Associate Professor in the Department of Surgery.

Research interests

Her research is centred on the role of bacteria in the pathogenesis of gastrointestinal disease.

She is particularly interested in the ability of outer membrane vesicles shed from the surface of Gram negative bacteria to induce epithelial permeability, inflammation and DNA damage.

Another interest is the influence of diet on bacterial phenotype and host response.

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Publications

Purcell, R. V., Kaakoush, N. O., Mitchell, H. M., Pearson, J. F., & Keenan, J. I. (2018). Gastrointestinal pathobionts in pediatric Crohn's disease patients. International Journal of Microbiology, 2018, 9203908. doi: 10.1155/2018/9203908

Aitchison, A., Hakkaart, C., Kahn, S., Whitehead, M., Frizelle, F., & Keenan, J. (2018). E-cadherin in early-onset colorectal signet-ring cell carcinoma. Proceedings of the New Zealand Society for Oncology (NZSO) Conference. Retrieved from http://www.nzsoncology.org.nz/

Swan, J., Aitchison, A., Hampton, M., & Keenan, J. (2018, September). Asprin's role in preventing e-cadherin cleavage by the carcinogenic Bacteroides Fragilis toxin. Poster session presented at the Otago Spotlight Symposium on Infectious Disease, Wellington, New Zealand.

Budd, G. R., Aitchison, A., Day, A. S., & Keenan, J. I. (2017). The effect of polymeric formula on enterocyte differentiation. Innate Immunity, 23(3), 240-248. doi: 10.1177/1753425916689333

Flores, S. E., Aitchison, A., Day, A. S., & Keenan, J. I. (2017). Helicobacter pylori infection perturbs iron homeostasis in gastric epithelial cells. PLoS ONE, 12(9), e0184026. doi: 10.1371/journal.pone.0184026

Journal - Research Article

Purcell, R. V., Kaakoush, N. O., Mitchell, H. M., Pearson, J. F., & Keenan, J. I. (2018). Gastrointestinal pathobionts in pediatric Crohn's disease patients. International Journal of Microbiology, 2018, 9203908. doi: 10.1155/2018/9203908

Budd, G. R., Aitchison, A., Day, A. S., & Keenan, J. I. (2017). The effect of polymeric formula on enterocyte differentiation. Innate Immunity, 23(3), 240-248. doi: 10.1177/1753425916689333

Flores, S. E., Aitchison, A., Day, A. S., & Keenan, J. I. (2017). Helicobacter pylori infection perturbs iron homeostasis in gastric epithelial cells. PLoS ONE, 12(9), e0184026. doi: 10.1371/journal.pone.0184026

Chae, A., Aitchison, A., Day, A. S., & Keenan, J. I. (2017). Bovine colostrum demonstrates anti-inflammatory and antibacterial activity in in vitro models of intestinal inflammation and infection. Journal of Functional Foods, 28, 293-298. doi: 10.1016/j.jff.2016.11.016

Purcell, R. V., Pearson, J., Aitchison, A., Dixon, L., Frizelle, F. A., & Keenan, J. I. (2017). Colonization with enterotoxigenic Bacteroides fragilis is associated with early-stage colorectal neoplasia. PLoS ONE, 12(2), e0171602. doi: 10.1371/journal.pone.0171602

Purcell, R. V., Pearson, J., Frizelle, F. A., & Keenan, J. I. (2016). Comparison of standard, quantitative and digital PCR in the detection of enterotoxigenic Bacteroides fragilis. Scientific Reports, 6, 34554. doi: 10.1038/srep34554

Keenan, J. I., Aitchison, A., Purcell, R. V., Greenlees, R., Pearson, J. F., & Frizelle, F. A. (2016). Screening for enterotoxigenic Bacteroides fragilis in stool samples. Anaerobe, 40, 50-53. doi: 10.1016/j.anaerobe.2016.05.004

Aitchison, A., Frizelle, F. A., & Keenan, J. I. (2016). PCR detection of the Bacteroides fragilis enterotoxin gene relies on robust primer design. Journal of Clinical Microbiology, 54(1), 239-240. doi: 10.1128/jcm.02785-15

Wakeman, C., Keenan, J., Eteuati, J., Hollington, P., Eglinton, T., & Frizelle, F. (2016). Chemoprevention of colorectal neoplasia. ANZ Journal of Surgery, 87(12), E228-E232. doi: 10.1111/ans.13392

Wright, E. K., Kamm, M. A., De Cruz, P., Hamilton, A. L., Ritchie, K. J., Keenan, J. I., … Burgess, L., Aitchison, A., … Day, A. S., & Gearry, R. B. (2016). Comparison of fecal inflammatory markers in Crohn's disease. Inflammatory Bowel Diseases, 22(5), 1086-1094. doi: 10.1097/mib.0000000000000671

Flores, S. E., Day, A. S., & Keenan, J. I. (2015). Measurement of total iron in Helicobacter pylori-infected gastric epithelial cells. Biometals, 28, 143-150. doi: 10.1007/s10534-014-9810-z

Tyrer, P. C., Frizelle, F. A., & Keenan, J. I. (2014). Escherichia coli-derived outer membrane vesicles are genotoxic to human enterocyte-like cells. Infectious Agents & Cancer, 9, 2. doi: 10.1186/1750-9378-9-2

Meijer, B., Hoskin, T., Ashcroft, A., Burgess, L., Keenan, J. I., Falvey, J., Gearry, R. B., & Day, A. S. (2014). Total soluble and endogenous secretory receptor for advanced glycation endproducts (RAGE) in IBD. Journal of Crohn's & Colitis, 8(6), 513-520. doi: 10.1016/j.crohns.2013.11.004

Keenan, J. I., Hooper, E. M., Tyrer, P. C., & Day, A. S. (2014). Influences of enteral nutrition upon CEACAM6 expression by intestinal epithelial cells. Innate Immunity, 20(8), 848-856. doi: 10.1177/1753425913513309

Keenan, J. I., Salm, N., Pearson, J. F., Gearry, R. B., & Day, A. S. (2013). Campylobacter seroreactivity in adults with recent onset of Crohn’s disease. Journal of Gastroenterology & Hepatology Research, 2(3), 468-472. doi: 10.6051/j.issn.2224-3992.2013.02.228

Bentley, R. W., Keown, D. A., Gearry, R. B., Cameron, V. A., Keenan, J., Roberts, R. L., & Day, A. S. (2012). Vitamin D receptor polymorphisms in colorectal cancer in New Zealand: An association study. New Zealand Medical Journal, 125(1356). Retrieved from http://www.nzma.org.nz/journal

Coray, D. S., Heinemann, J. A., Tyrer, P. C., & Keenan, J. I. (2012). Human lactoferrin increases Helicobacter pylori internalisation into AGS cells. World Journal of Microbiology & Biotechnology, 28(5), 1871-1880. doi: 10.1007/s11274-011-0984-z

Keown, D. A., Collings, D. A., & Keenan, J. I. (2012). Uptake and persistence of Mycobacterium avium subsp. paratuberculosis in human monocytes. Infection & Immunity, 80(11), 3768-3775. doi: 10.1128/iai.00534-12

Parker, H., & Keenan, J. I. (2012). Composition and function of Helicobacter pylori outer membrane vesicles. Microbes & Infection, 14(1), 9-16. doi: 10.1016/j.micinf.2011.08.007

Keenan, J. I., Salm, N., Wallace, A. J., & Hampton, M. B. (2012). Using food to reduce H. pylori-associated inflammation. Phytotherapy Research, 26(11), 1620-1625. doi: 10.1002/ptr.4618

Glubb, D. M., Gearry, R. B., Barclay, M. L., Roberts, R. L., Pearson, J., Keenan, J. I., McKenzie, J., & Bentley, R. W. (2011). NOD2 and ATG16L1 polymorphisms affect monocyte responses in Crohn's disease. World Journal of Gastroenterology, 17(23), 2829-2837. doi: 10.3748/wjg.v17.i23.2829

Day, A. S., & Keenan, J. (2011). Probiotic-mediated modulation of host inflammation. Expert Review of Gastroenterology & Hepatology, 5(3), 319-321. doi: 10.1586/egh.11.34

Keenan, J. I., Salm, N., Hampton, M. B., & Wallace, A. J. (2010). Individual and combined effects of foods on Helicobacter pylori growth. Phytotherapy Research, 24(8), 1229-1233. doi: 10.1002/ptr.3167

Keenan, J. I., Beaugie, C. R., Jasmann, B., Potter, H. C., Collett, J. A., & Frizelle, F. A. (2010). Helicobacter species in the human colon. Colorectal Disease, 12(1), 48-53. doi: 10.1111/j.1463-1318.2008.01672.x

Parker, H., Chitcholtan, K., Hampton, M. B., & Keenan, J. I. (2010). Uptake of Helicobacter pylori outer membrane vesicles by gastric epithelial cells. Infection & Immunity, 78(12), 5054-5061. doi: 10.1128/IAI.00299-10

Munday, J. S., Keenan, J. I., Beaugie, C. R., & Sugiarto, H. (2009). Ovine small intestinal adenocarcinomas are not associated with infection by herpesviruses, Helicobacter species or Mycobacterium avium subspecies paratuberculosis. Journal of Comparative Pathology, 140(2-3), 177-181. doi: 10.1016/j.jcpa.2008.11.005

Bentley, R. W., Keenan, J. I., Gearry, R. B., Kennedy, M. A., Barclay, M. L., & Roberts, R. L. (2008). Incidence of Mycobacterium avium subspecies paratuberculosis in a population-based cohort of patients with Crohn's disease and control subjects. American Journal of Gastroenterology, 103(5), 1168-1172. doi: 10.1111/j.1572-0241.2007.01742.x

Chitcholtan, K., Hampton, M. B., & Keenan, J. I. (2008). Outer membrane vesicles enhance the carcinogenic potential of Helicobacter pylori. Carcinogenesis, 29(12), 2400-2405. doi: 10.1093/carcin/bgn218

Keenan, J. I., Davis, K. A., Beaugie, C. R., McGovern, J. J., & Moran, A. P. (2008). Alterations in Helicobacter pylori outer membrane and outer membrane vesicle-associated lipopolysaccharides under iron-limiting growth conditions. Innate Immunity, 14(5), 279-290. doi: 10.1177/1753425908096857

Piuhola, J., Kerkelä, R., Keenan, J. I., Hampton, M. B., Richards, A. M., & Pemberton, C. J. (2008). Direct cardiac actions of erythropoietin (EPO): Effects on cardiac contractility, BNP secretion and ischaemia/reperfusion injury. Clinical Science, 114(4), 293-304. doi: 10.1042/CS20070229

Mandhan, P., Qi, B. Q., Keenan, J. I., Ismail, S., Beasley, S. W., & Sullivan, M. J. (2006). Counterstaining improves visualization of the myenteric plexus in immunolabelled whole-mount preparations. Journal of Fluorescence, 16, 655-658.

Keenan, J. I., Peterson, II, R. A., & Hampton, M. B. (2005). NADPH oxidase involvement in the pathology of Helicobacter pylori infection. Free Radical Biology & Medicine, 38, 1188-1196.

Hynes, S. O., Keenan, J. I., Ferris, J. A., Annuk, H., & Moran, A. P. (2005). Lewis epitopes on outer membrane vesicles of relevance to Helicobacter pylori pathogenesis. Helicobacter, 10(2), 146-156.

Keenan, J. I., Peterson, R. A., Fraser, R., Frampton, C. M., Walmsley, T. A., Allardyce, R. A., & Roake, J. A. (2004). The effect of Helicobacter pylori infection and dietary iron deficiency on host iron homeostasis: A study in mice. Helicobacter, 9(6), 643-650.

Bland, M. V., Ismail, S., Heinemann, J. A., & Keenan, J. I. (2004). The action of bismuth against Helicobacter pylori mimics but is not caused by intracellular iron deprivation. Antimicrobial Agents & Chemotherapy, 48(6), 1983-1988.

Arsic, D., Cameron, V., Ellmers, L., Quan, Q. B., Keenan, J., & Beasley, S. (2004). Adriamycin disruption of the Shh-Gli pathway is associated with abnormalities of foregut development. Journal of Pediatric Surgery, 39(12), 1747-1753.

Keenan, J. I., Rijpkema, S., Durrani, Z., & Roake, J. A. (2003). Differences in immunogenicity and protection in mice and guinea pigs following intranasal immunization with Helicoba pylori outer membrane antigens. FEMS Immunology & Medical Microbiology, 36(3), 199-205.

Ismail, S., Hampton, M. B., & Keenan, J. I. (2003). Helicobacter pylori outer membrane vesicles modulate proliferation and interleukin-8 production by gastric epithelial cells. Infection & Immunity, 71(10), 5670-5675.

Arsic, D., Keenan, J. I., Quan, Q., & Beasley, S. W. (2003). Differences in the levels of Sonic hedgehog protein during early foregut development caused by exposure to Adriamycin give clues to the role of the Shh gene in oesophageal atresia. Pediatric Surgery International, 19, 463-466.

Hampton, M. B., Vissers, M. C., Keenan, J. I., & Winterbourn, C. C. (2002). Oxidant-mediated phosphatidylserine exposure and macrophage uptake of activated neutrophils: possible impairment in chronic granulomatous disease. Journal of Leukocyte Biology, 71(5), 775-781.

Keenan, J. I., Neal, S., Allardyce, R. A., & Roake, J. A. (2002). Serum-derived IgG1-mediated immune exclusion as a mechanism of protection against H.pylori infection. Vaccine, 20, 2981-2988.

Keenan, J. I., Day, T., Neal, S., Cook, B., Perez-Perez, G., Allardyce, R. A., & Bagshaw, P. F. (2000). A role for the bacterial outer membrane in the pathogenesis of Helicobacter pylori infection. FEMS Microbiology Letters, 182, 259-264.

Keenan, J., Oliaro, J., Domigan, N., Potter, H., Aitken, G., Allardyce, R., & Roake, J. (2000). Immune response to an 18-kilodalton outer membrane antigen identifies lipoprotein 20 as a Helicobacter pylori vaccine candidate. Infection & Immunity, 68(6), 3337-3343. doi: 10.1128/IAI.68.6.3337-3343.2000

Keenan, J. I., & Allardyce, R. A. (2000). Iron influences the expression of Helicobacter pylori outer membrane vesicle-associated virulence factors. European Journal of Gastroenterology & Hepatology, 12, 1-7.

Keenan, J. I., Allardyce, R. A., & Bagshaw, P. F. (1998). Lack of protection following immunisation with H-pylori outer membrane vesicles highlights antigenic differences between H-felis and H-pylori. FEMS Microbiology Letters, 161(1), 21-27.

Allardyce, R. A., Chapman, B. A., Tie, A. B., Burt, M. J., Yeo, K. J., Keenan, J. I., & Bagshaw, P. F. (1997). 37 kBq 14C-urea breath test and gastric biopsy analysis of H. pylori infection. Australian & New Zealand Journal of Surgery, 67(1), 31-34. doi: 10.1111/j.1445-2197.1997.tb01890.x

Keenan, J. I., Allardyce, R. A., & Bagshaw, P. F. (1997). Dual silver staining to characterise helicobacter spp. outer membrane components. Journal of Immunological Methods, 209(1), 17-24.

Allardyce, R. A., Bagshaw, P. F., & Keenan, J. I. (1995). The outcome of Helicobacter pylori infection. British Journal of Hospital Medicine, 54, 372-377.

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Journal - Research Other

Keenan, J., Aitchison, A., & Frizelle, F. (2017). Are young people eating their way to bowel cancer? New Zealand Medical Journal, 130(1460), 90-92. Retrieved from https://www.nzma.org.nz/journal

Hock, B. D., McKenzie, J. L., & Keenan, J. I. (2017). Helicobacter pylori outer membrane vesicles inhibit human T cell responses via induction of monocyte COX-2 expression [Short communication]. Pathogens & Disease, 75(4), ftx034. doi: 10.1093/femspd/ftx034

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