• De Souza, Andy

    Titles

    Investigator, BC Children's Hospital
    Scientist, Department of Pathology & Laboratory Medicine, BC Children's Hospital
    Clinical Assistant Professor, Department of Pathology & Laboratory Medicine, Faculty of Medicine, University of British Columbia 

    Degrees / Designations

    PhD

    Primary Area of Research
    Childhood Diseases
    Secondary Area(s) of Research
    Phone
    604-875-2435 ext. 7449
    Fax
    604-875-3434
    Lab Phone
    Mailing Address
    BC Children's Hospital
    Room 2F19
    4500 Oak St.
    Vancouver, BC V6H 3N1
    Affiliate Websites
    Research Areas
    • Inborn errors of metabolism 
    • Newborn screening 
    • Mass spectrometry in clinical diagnoses
    Summary

    Mass spectrometry is a powerful analytical technique with widespread applications, including the clinical laboratory.  In the Newborn Screening (NBS) and Biochemical Genetics Laboratories (BGL) at BC Children’s Hospital, we utilize tandem mass spectrometry (MS/MS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) to identify and quantify analytes of interest in biological matrices (e.g., blood, plasma, serum, cerebrospinal fluid, urine), which aids in the diagnoses of disorders.  My research interests focus on the application of tandem mass spectrometry in clinical diagnoses of inborn errors of metabolism. 

    Current Projects

    Amino acid disorders are a class of inherited metabolic disorders which can be attributed to an enzyme deficiency in metabolic pathways, resulting in the toxic accumulation of some substances and the deficiency of others.  The measurement of amino acids in plasma is essential in the diagnosis of inborn errors of metabolism (IEM) and the monitoring of affected patients.  We developed and validated an LC-MS/MS method to measure amino acids in plasma.  Compared to the previous method used in BGL, our new method allows for a higher volume of samples to be analyzed in a day, and has reduced turn-around-times.  The next phase of this project is to validate and implement an LC-MS/MS method for urine and cerebrospinal fluid amino acid analyses.

    Niemann-Pick Disease Type C (NPC1) is a rare autosomal recessive lysosomal storage disorder, which leads to progressive neurological dysfunction. There is currently limited non-invasive diagnostic testing for NPC1. Therefore, it often goes undiagnosed until advanced symptoms are present. This is particularly true for pediatric cohorts.  A novel treatment has recently become available for NPC1, making the need for a non-invasive test even more important. Our laboratory aims to implement a screening assay using LC-MS/MS to test for NPC1 in plasma. This will alleviate the diagnostic delay and enable timely treatment. 

    Selected Publications

    De Souza, A. G.; MacCormack, T. J.; Wang, N.; Li, L.; Goss, G. G. Large scale proteome profile of the zebrafish (Danio rerio) gill for physiological and biomarker discovery studies. Zebrafish. 2009, 6, 229-238. PMID: 19715488

    Wishart, D. S.; Knox, C.; Guo, A. C.; Eisner, R.; Young, N.; Gautam, B.; Hau, D. D.; Psychogios, N.; Dong, E.; Bouatra, S.; Mandal, R.; Sinelnikov, I.; Xia, J.; Jia, L.; Cruz, J. A.; Lim, E.; Sobsey, C. A.; Shrivastava, S.; Huang, P.; Liu, P.; Fang, L.; Peng, J.; Fradette, R.; Cheng, D.; Tzur, D.; Clements, M.; Lewis, A.; De Souza, A.; Zuniga, A.; Dawe, M.; Xiong, Y.; Clive, D.; Greiner, R.; Nazyrova, A.; Shaykhutdinov, R.; Li, L.; Vogel, H. J.; Forsythe, I. HMDB: A knowledge base for the human metabolome. Nucleic Acids Res. 2009, 37, D603 - D610. PMID: 24218206

    Wang, N.; MacKenzie, L.; De Souza, A. G.; Zhong, H.; Goss, G.; Li, L. Proteome profile of cytosolic component of zebrafish liver generated by LC-ESI MS/MS combined with trypsin digestion and microwave-assisted acid hydrolysis. J. Proteome Res. 2007, 6, 263-272. PMID: 17203970

    Grants
    Honours & Awards

    Profiling Alberta’s Graduate Student Award, University of Alberta, 2009
    Graduate Student Scholarship, Government of Alberta, 2006
    Walter H. Johns Graduate Fellowship, University of Alberta, 2005
    NSERC PGS-M, NSERC, 2005
    Graduate Entrance Scholarship, University of Alberta, 2004

    Research Group Members