Investigators - Basic science - muczynski

Kimberly Muczynski, MD, PhD

Dr. Muczynski's overall focus is on the human immune system and its role in native and transplant human kidney disease. She has particular interest in endothelial cells as they relate to renal immunology.

Project 1: Evaluating the role and regulation of HLA class II proteins on renal microvascular endothelial cells

Normal human renal capillary endothelial cells express high levels of HLA-DR unassociated with an immune response. Endothelial cells also control the passage of immune effector cells into the kidney. Human kidney endothelial cells are being isolated by flow cytometry based on their HLA-DR expression and analyzed for expression of other genes affecting antigen processing and presentation, T-lymphocyte activation and infiltration of leukocytes. The goals of this project are to understand the role of microvascular HLA-DR in human kidneys and to identify molecular targets for immune therapies. The work is being done in collaboration with colleagues in the Netherlands.

Project 2: Assessing inflammation and immune responses in human kidney biopsies by multicolor flow cytometry

Flow cytometry, a technology that has proven invaluable for hematopathology, is 100-fold more sensitive for a detection of cell surface proteins than standard microscopic examination of kidney biopsies. Transplant renal biopsies are being evaluated with this technique to distinguish conditions that otherwise appear similar in standard kidney biopsies. For example, a viral infection known as BK nephropathy often appears the same as rejection by histology, yet these conditions have totally different treatments. The goals of this work is to characterize immune effector cells causing damage in transplanted kidneys in order to better direct therapy.

Project 3: Proliferative potential of human kidney endothelial cells

Human kidney endothelial cells can be isolated by flow cytometry based on surface protein expression. When these cells are cultured and cloned, some cells divide a couple times and then die while others divide many times to form large colonies of cells. Subcloning yields similar results. HLA-DR expression of transplant kidney endothelial cells is being evaluated to determine if microvascualr endothelial cells are of donor or recipient origin. Even in decade old transplanted kidneys, virtually all of the endothelial cells remain donor derived. This has lead us to hypothesize that the endothelium contains its own precursor cells which retain high proliferative capacity, even into the eighth decade of life, and that bone marrow-derived endothelial precursors are not required for repair of human renal vasculature.

Project 4: Urinary excretion of donor genomic DNA as a marker of kidney allograft injury

Urine provides a window into the kidney. By anaylzying urine from kidney transplant patients for genomic DNA from the donor and recipient it may be possible to determine when an allograft is being injured. The goal of this research is to find a way to monitor the immune system in kidney transplants with fewer invasive kidney biopsies. This project is being done in collaboration with Dr. VK Gadi.

Project 5: Identification of a novel gene regulating HLA class II antigen presentation by complementation of the mutation in 2.7.93

Genetic mutation provides a unique opportunity for understanding the normal functioning of a gene product. Mutagenesis of a B-lymphoblastoid cell line with a hemizygous deletion in the MHC region of chromosome 6 produced a cell line designated 2.7.93 which has a bimodal expression of the DR epitope recognized by the binding of the antibody 16.23. The 16.23 epitope requires the expression of both DM and DR. The bimodal expression of 16.23 persists after multiple rounds of cloning, indicating that it is likely due to a mutation and not to a mixed population of cells. Retroviral library complementation failed to restore 2.7.93 to its wildtype phenotype suggesting that the defect may be within the hemizygous deletion area of chormosome 6 in a gene containing that rare restriction site used to construct the library. Putative genes are being evaluated for their ability to correct the 2.7.93 phenotype. The technique of haplotype mutagenesis to identify gene function has wide application to other biological functions.

Project 6: Human allogeneic parathyroid transplant for congenital hypoparathyroidism

Congenital hypoparathyroidism is a very rare condition that is managed by supplemental calcium to prevent symptomatic hypcalcemia. The long term consequence of this therapy is the development of nephrocalcinosis and renal failure. Dr. Muczynski has IRB (human subjects) approval for living and deceased donor parathyroid transplants to correct congenital hypoparathryoidism. The initial parathyroid transplant will be done in conjunction with a kidney transplant. An appropriate recipient has been identified for the first combined kidney-parathyroid transplant. Research thyroids are being obtained from Lifecenter, the local organ procurement organization, to practice isolation of normal parathyroids. Dr. Gary Mann is the surgical collaborator on this project. Dr. Paul Swanson is the collaborating pathologist.

Current Funding

Kidney Immunology Research Fund (2004-present)

Past Funding

Research Royalty Award (2002-2003)
University of Washington

Atorvastatin Research Award (2001-2003)

NIH (PIs D. Pious and T. Cotner) (2001)

HHMI Research Resources Program for Medical Schools (1998-2000)

Northwest Kidney Foundation (1997-99; 2000-01)

K-Award (1992-1996)

Current Research Members

Susan K Anderson, MS: Research scientist with three decades of experience at the University of Washington and extensive publications. Expertise in electron and immunoelectron microscopy, immunofluorescence and confugal microscopy, flow cytometry, tissue culture, antibody purification and conjugation

Past Research members

Brian Gallay, MD, PhD: Investigated endothelial activation and kidney transplant rejection.
Current Position: Faculty, Transplant Nephrology, University of California, Davis

Mark Joseph, MD: Characterized the genetic defect in a new bare lymphocyte syndrome patient
Current Position: Private Practice

Greg Sharp, MD: Sequenced a mutant variant of the MHC II transcription factor, RFX5
Current Position: Private Practice

Elizabeth Skirm, MD: Development of a methodology to investigate cryoglobulins and immune complexes in the pathogenesis of hepatitis C associated membranoproliferative glomenulonephritis
Current Position: Private Practice

Michael Tasch, MD, PhD: Investigated nephrin expression in the thymus
Current Position: Benaroya Research Institute, Seattle, WA


PubMed provides a list of Dr. Muczynski's research publications