*Please note that you can also submit your CV through our website, it will be shared with other principal investigators
Identifying Novel Biomarkers to Predict Kidney Transplantation Graft Outcomes and identify Novel Therapeutic Targets
SUPERVISOR: Dr. Jean Tchervenkov, MD (Summer Student Projects)
Director of Living Donor Renal Transplantation, Royal Victoria Hospital
Surgical Director of Pediatric Renal Transplantation at the McGill University Health Centre
Acute kidney injury (AKI) occurs in kidney transplantation and results in slow graft function (SGF) and delayed graft function (DGF) in 20% of recipients. DGF can eventually lead to acute rejection (AR) and progress to chronic allograft nephropathy (CAN). DGF has been shown to be a more potent predictor of adverse long-term outcomes, as well as acute and chronic rejection. SGF, the milder form of AKI is another risk factor for long-term graft dysfunction and acute rejection. Therefore donor-derived or recipient associated new biomarkers of predicting AKI and DGF are required to modify our organ allocation criteria and to develop novel therapeutic interventions.
Project 1: Kidney Transplant Patient TReg Phenotyping
Regulatory T cells (Treg) are critical in immune tolerance of the graft and hypothesized to promote allograft acceptance. We have shown that recipient’s pre-transplant Treg suppressive function was predictive of AKI as well as discriminates DGF from immediate graft function (IGF) in our deceased donor kidney transplant recipients. Tregs are a very heterogenous population in term of phenotype or function and additional markers are required to identify Tregs with potent suppressive function. Tumor necrosis factor receptor 2 (TNFR2) is expressed on Tregs and it mediates signaling effect of TNFa to improve Tregs cell survival and suppressive function. We are collecting samples from kidney transplant patients across Montreal and our goal is to identify pre, peri and post transplant TReg function and correlate this data to clinical parameters.
Project 2: Kidney machine perfusion exosome profiling
A specific project in our laboratory will focus on the identification of any donor-associated factors to predict graft outcomes. Generally, donor kidneys are perfused on a machine perfusion system, called LifePort prior to the transplant. We have collected >50 kidney perfusion samples to date. Our hypothesis in this study is that the perfusion fluid collected from the Lifeport could be a very important resource to identify kidney-injury biomarkers and to assess the quality of donor kidneys and guide management and allocation of the organ. We have already confirmed the presence of EVs in kidney perfusates by Nanosight and Cytoflex. EVs from kidney perfusates will be characterized for their content by proteomics, microFACS, microRNA sequencing and Cytoflex. We will also evaluate EVs for their immunomodulatory potential by measuring recipient’s T- or B-lymphocyte activation mediated by donor EVs. Flow cytometry, ELISA, ELISPOT will be used to measure T- or B-cell activation. We will also assess kidney perfusates for other markers of ischemia-reperfusion injury for example mitochondrial content, ATP and cytokine levels and correlate with graft outcomes.
To submit your candidature:
Skin alarms: identifying factors in human skin controlling Th2 polarization
SUPERVISOR: Dr. Carolyn Jack, MD, PHD (Summer Student Projects)
Hypothesis/Question to be Addressed
A sub-type of the adaptive immune response that evolved to fight parasites is now recognized to play a key role in the widely prevalent skin disease, atopic dermatitis (eczema). This response involves excessive T helper 2 type (Th2)-cytokines and signaling in the skin of human patients. We seek to determine the skin-derived cytokines and ‘alarmin’ signals that can polarize T cells into Th2-cytokine producing cells, central to human disease.
We have validated a novel model for atopic dermatitis using human Th2-type cytokine-secreting T cells in vitro. This model exposes human peripheral blood-derived T cells to two activation factors, both of which can be found in the skin under conditions of disease. T cells are activated with a bacterial super-antigen as well as a skin (keratinocyte)-derived cytokine, released upon tissue damage, also known as ‘alarmin.’ We seek to:
- Determine which inflammation related-factors, including alarmins and cytokines, found elevated in the skin of atopic dermatitis patients, are sufficient to induce Th2 polarization in combination with bacterial superantigens, as determined using our human atopic dermatitis cytokine-secretion in vitro model
- Determine dose-response curves for each potential Th2-polarizing factor as well as their capacity for synergetic potentiation, in the induction of the Th2 cytokine, IL-13
- Characterize cell surface markers and phenotypes of the above Th2-type T cells using flow cytometry
Role of Student
The tasks of the student in the lab will include, but will not be restricted to:
- Identify candidate molecules, including alarmins and cytokines, that can potentially induce Th2 differentiation by synergizing with bacterial superantigens using state-of-the-art per-reviewed scientific publications in the NCBI database.
- Prepare, maintain and activate primary cultures of human peripheral blood mononuclear cells (PBMCs)
- Isolate T cells using magnetic-beads derived technology and flow cytometric isolation.
- Characterize different sub populations of T lymphocytes using flow cytometric techniques
- Analyze the activation status of T lymphocytes based on surface and cell-signaling proteins using flow cytometric techniques.
- Assess the cytokine profiling of Th2 activated lymphocytes by flow cytometry and Enzyme-Linked Immunosorbent Assay (ELISA).
- Design and planning of experimental procedures.
- Prepare buffers, equipment and bio-active substances aliquots for T cell culturing.
- Maintain detailed scientific records
- Write final reports including a peer-reviewed scientific publication showing the newly-identified factors involved in Th2 differentiation.
To submit your candidature: