2005 Annual Report

2005 Annual Report

Professional Staff

A. Jake Demetris, M.D. (Division Director)  Professor
Rene J. Duquesnoy, Ph.D.  Professor
Michael A. Nalesnik, M.D.  Professor
Erin Ochoa, M.D.  Assistant Professor 
Parmjeet S. Randhawa, M.D.  Professor
Tong Wu, M.D., Ph.D.  Associate Professor
Adriana Zeevi, Ph.D.  Professor
*Dr. Ochoa is a new faculty member, joining us in Sept. 2004.

FROM ANNUAL REPORT 2005

DIVISION OF TRANSPLANTATION PATHOLOGY


Clinical Activities
Formally established in 1990, the Division of Transplant Pathology plays an integral part in the comprehensive transplant program at the University of Pittsburgh Medical Center and its satellite center in Palermo, Italy.  The mission of the Division is to provide up-to-date laboratory services emphasizing continued excellence in patient care, to provide expert consultation, to foster an academic environment devoted to education and training, and to conduct basic and clinically oriented research in transplantation pathology.  A nucleus of professionals with expertise in pathology, immunology and molecular biology is actively involved in many transplantation related research projects at the Thomas E.  Starzl Transplantation Institute.

The Division offers a wide range of laboratory tests and tissue analyses for patients and experimental studies.  Routine histology, specialized immunocytochemistry and in situ hybridization procedures are performed on tissues from patients under consideration for transplantation, on native organ resections and on post-transplant biopsies.  These procedures assure consistency of analysis and continuity of patient care.  Post-transplant monitoring assays deal with lymphocyte reactivity and cytokine production and detection of cytomegalovirus, Epstein-Barr virus, and Hepatitis viruses, among other infectious agents.

The division has established and maintains an active telepathology consultation service.  We developed a specific HIPPA-compliant software with Diversified Services, Inc. that is used to triage and respond to cases.  We have also recently integrated robotic microscope capabilities (Trestle Systems) into the software applications.

Drs. Zeevi and Duquesnoy are the Co-Directors of the UPMC-Presbyterian Tissue Typing Laboratory, which offers histocompatibility-testing services to the organ transplantation program at the University of Pittsburgh Medical Center.  In 2004, this laboratory performed donor workups as follows: kidney transplants from living donors (98), non-living donors (100), liver transplants from living donors (38), non-living donors (256), transplant of pancreas (29), kidney/pancreas (23), heart (53), intestine (48), lung (50), and double lung (20).

The Division offers comprehensive consultation in liver, kidney, and solid organ transplantation pathology to community and university-based physicians.  The scope of this service encompasses the evaluation of liver, heart, intestinal and kidney disease in prospective transplantation candidates, donor recipient histocompatibility issues, the examination of native explanted organs, and the evaluation of post-transplant biopsies or resections to evaluate the causes of allograft dysfunction such as infection, ischemia, rejection, technical complications, recurrent disease and post-transplant malignancies.  These consultation services are also available through the Internet (http://path.upmc.edu/divisions/transpath/hepa00.html).
 
For the period of July 1, 2004 through June 30, 2005, the professional workload on outside consultation cases was:

Anthony J. Demetris, M.D.: 286 cases
Michael A. Nalesnik, M.D.: 315 cases
Parmjeet Randhawa, M.D.: 269 cases
Tong Wu, M.D., Ph.D: 234 cases
Erin Ochoa, M.D.: 107 cases

Research Activities
The Division has a strong commitment to research in transplantation.  Each professional is actively engaged in research projects frequently in collaboration with members of other departments, in particular, Transplant Surgery.  Over the year, faculty of the Division contributed 62 refereed publications, invited reviews and book chapters.  Thirty-two invited lectures and scientific meeting presentations were given outside the institution, including 15 talks abroad.  Several members serve on grant review committees and editorial boards of major professional journals.

Current research activities deal with a variety of projects:

Studies on the role of IL-6 in liver disease have shown that this cytokine is essential for maintaining biliary tree integrity and liver mass under conditions of biomedical stress, such as obstructive cholangiopathy.  Using IL-6 deficient mice, a model of accelerated development and decompensation of biliary cirrhosis has been established.  Analysis of IL-6/gp/30-dependent transcription factor activation is being used to determine how these signaling pathways contribute to the phenotype observed.

Experimental animal and clinical studies show that the development of cirrhosis and decompensation are heavily influenced by oxidative stress in hepatocytes, which up regulates the cyclin-dependent kinase inhibitor, p21.  This in turn, inhibits hepatocyte proliferation and accelerates the development of cirrhosis and decompensation.

The Research Histology Laboratory of the Division serves as the Core Liver Tissue Laboratory for the Immune Tolerance Network (ITN).  Specific Web-based software has been developed to communicate results to investigators throughout the world on a real time basis.  Data management tools are being developed for this application.

The division also maintains a robust clinical database, as a part of EDIT (Electronic Data Interface for Transplantation).  This database links histology diagnoses and histologic finding with a multitude of clinical, serologic, matching, donor and outcome parameters.  The database is an invaluable resource for clinical and patient-based research activities.

Dendritic cells play an important role in inflammatory diseases, including allograft rejection, and steatohepatitis, as well as in tolerance to solid organ allografts.  IL-6/gp130 signaling plays an important role in their maturation.  Continuing studies are investigating the role of IL-6 dependent co-factors in dendritic cells maturation.

During rejection, cardiac allografts undergo a stress response, which leads to an increased expression of heat shock proteins and the infiltration of hsp-dependent autoreactive lymphocytes.  Heat shock proteins also play a role in transplant immunity associated with chronic rejection.

Serological studies deal with the characterization of antibodies against private and public HLA epitopes and their correlation with amino acid residues.  Screening of sera from highly sensitized patients permits the identification of potential donors with acceptable mismatches and the assessment of the relative immunogenicity HLA antigens.

A computer algorithm has been developed (HLA Matchmaker) that assesses donor- recipient HLA compatibility at the amino acid structural level.  The algorithm makes intralocus and interlocus comparisons of amino acid triplets of HLA class I antigens.

Lung Transplantation is the only therapeutic option for many fatal lung diseases.  The current immunosuppression protocols based on systemic cyclosporine or tacrolimus are not adequate to control rejection.  A unique option is to target a high concentration of the immunosuppressive drugs to the lung allograft without increasing the systemic levels that might be toxic.  Studies are conducted in lung transplant patients that receive aerosol CsA and in control patients on the role of various cytokines and effector molecules that can cause allograft damage and dysfunction.  We also evaluate the impact of aerosol CsA on suppressing alloreactive T cells, on the alloantibody formation and release of soluble donor derived HLA antigen.  We are correlating the laboratory finding with the clinical parameters and determining whether these tests can be used as early markers of allograft damage.

Based on in vitro and in vivo evaluation or cytokine production, it has been possible to characterize individuals as "high" or "low" producers for a given cytokine.  Such polymorphisms correspond to allelic variation that can be determined by DNA genotyping.  We are interested to study what the relationship is between cytokine polymorphism and clinical outcome after organ transplantation.  High may develop more acute producers of proinflammatory cytokines such as TNF- rejection and require augmented immunosuppression.  Iin contrast, patients with  and high IL-10 genotype (a suppressive cytokine) may experience less low TNF- rejection.  Cytokine polymorphisms may also influence other post-transplantation outcomes such as infections and allergic side effects of immunosuppressive agents.

Post-transplant lymphoproliferative disease cytokine analysis of autologous EBV infected B cells has indicated Th2 type responsiveness during PTLD and Th1 type responses in normal EBV seropositive individuals. 

Autologous lymphokine-activated killer (LAK) cell therapy has been successfully used to treat lymphoproliferative disorders arising in organ transplant patients.

The clinical profile of patients with BK virus infection in the renal allograft is defined.  DNA sequencing of viral strains is being used to define mutations and genomic rearrangements, which may be relevant to the pathogenesis of an extremely refractory interstitial nephritis seen in these individuals.  Quantitative PCR assays have been developed to measure viral load in biopsy samples and body fluids to better manage the immunosuppression levels in these patients.  The interplay between host and viral immune factors in this disease is being investigated by DNA microarray technology.  Drugs with antiviral activity are being screened in an in-vitro culture model for possible future use in the clinical arena.

Studies on human hepatocytes have shown that IL-6 and HGF regulate the activity of cytosolic phospholipase A2 (cPLA2) in cultured human hepatocytes.  The regulation of cPLA2 by cytokines and growth factors may play a role in the pathophysiology of inflammatory and non-inflammatory liver diseases.

Image analysis approaches are being applied to biopsy interpretation.  Semi automated morphometry is being coupled with a neural network approach to evaluate fibrosis stage in chronic hepatitis, and image recognition algorithms in conjunction with multispectral analysis are being applied to the problem of rejection evaluation in kidney biopsies.

Human hepatobiliary cancers show increased expression of cyclooxygenase-2 (COX-2).  Studies have demonstrated that activation of Akt is an important mechanism by which COX-2 promotes hepatobiliary cancer growth.  Interruption of the COX-2 and prostaglandin signaling pathways is being targeted for the chemoprevention and treatment of human hepatobiliary cancers. 

Peroxisome proliferator activated receptor-gamma (PPAR-gamma) ligands have been shown to inhibit human cholangiocarcinoma growth via a p53-dependent mechanism.  These pharmacological agents may represent promising therapeutic agents for the treatment of human cholangiocarcinoma.   

Targeting p27kip1 to improve hepatocyte transplantation research.  In characterizing the cell-cycle regulatory role of the cyclin-dependent kinase inhibitor, p27kip1, it was discovered that p27 knockout mice exhibit pronounced multi-organomegaly with no increased spontaneous carcinogenesis in the liver.

Optimizing outcome after pediatric heart transplantation.  This project focuses on different aspects of pediatric heart transplantation and how to optimize outcomes and minimize drug-related complications.

Teaching/Training Activities
The Division is strongly devoted to teaching and training in transplantation pathology.  Professional staff directed graduate students and medical students in subjects, such as Cancer Biology, Digestion & Nutrition, Immunology & Inflammation, Kidney Pathology, and Molecular Pathology.  Visitors, including fellows and pathologists from Turkey, Peru, Columbia, India, Nigeria, and Canada, came to the Division for further training in transplant pathology.

The division also heads the Banff Working Group on Liver Allograft Pathology.  This group sets international guidelines for liver allograft biopsy interpretation and meets every two years to present new findings in the field and discuss futures directions.

Many pathology residents have rotated through the Division to receive training in transplantation, hepatic and renal pathology.  This rotation is designed to provide a basic understanding of the molecular, cellular and histopathologic mechanisms of transplant immunity, allograft rejection opportunistic infections, organ preservation injury, recurrent disease, drug toxicity graft versus host disease and lymphoproliferative disease.  During this rotation, the residents attended various transplant conferences, research meetings and special lectures.

The Division conducts weekly interdisciplinary conferences on heart, kidney, kidney/pancreas, intestine, liver and native liver pathology.  Conferences in conjunction with Transplant Surgery deal with liver transplant tumors and Transplant Grand Rounds.  There are also bimonthly meetings to discuss research progress within the Division and weekly journal clubs.

Transplant Pathology Internet Service (TPIS)
Transplant Pathology Internet Services (TPIS): An Interactive Platform for the Standardization of Transplantation Pathology Practice TPIS is a worldwide web-based venture of the Division of Transplantation Pathology and was originally designed to foster collaboration among transplant institutions. It has grown to over 2,500 pages and has evolved into an educational and interactive medium promoting both communication and standardization of transplant pathology practice. It performs this role using a three-pronged approach:

The first and largest component of TPIS is didactic and follows classical web-based design. Twenty-nine separate transplant-related histologic grading systems are incorporated with hyperlinked photomicrographs, serving as a de facto standard for biopsy interpretation. One hundred sixty-five separate consult cases, stripped of patient identifiers, are presented with full discussion. In addition, separate didactic sections covering the handling and pathology of all major transplant organs are presented. A full- length textbook, abstracts and a separate with all references hyperlinked to PubMed Immunopathology module provide complementary information for the transplant pathologist. Several video lectures are also available on the site.

The second component comprises interactive education. A case conference module containing 101 separate transplant-related cases represents a major portion of this section. Users can contribute cases or join in discussions of cases. (A separate electronic forum also serves an educational purpose, but has found its main use as a collaborative tool). A separate histopathologic testing module that can be modified for self-assessment or centralized scoring was added to conduct pathologist standardization testing for an international clinical drug trial. This approach, which can also be used for continuing medical education, has widespread applicability for multi-center studies involving pathologists.

The third component that encourages standardized practice is an interactive portion directed toward altering the practice of the individual pathologist. In the simplest case, TPIS serves as a download site for specialized software. At present we are offering software that performs HLA matching using the CREG approach and written within our group, and we are also offering telepathology software on a contractual basis. A second approach uses Java applets to perform medical calculations, allowing the user to perform calculations directly through the web browser. We have integrated five separate formulas that calculate creatinine clearance based on different clinical variables and offer all of these within our site. Similar calculations can be performed for determination of hepatic iron index. Finally, we are developing webware, based on the ImageJ applet from the NIH that allows the pathologist to perform problem-directed image analysis such as area measurement or nuclear counting directly through the browser.  The creation of such small, easy to use modules will not only offer additional tools to the practicing pathologist but will serve to enhance image interpretation and offer a new standard of practice for anatomic pathology.

In the last year, TPIS received 4,607,135 hits with an average of 12,622 (or 3501) pages viewed per day, transferring 108.116 gigabytes of data. Definitive and freely available information-rich sites such as TPIS are likely to become powerful voices in molding the practice of pathology in the immediate future.  We are presently upgrading our case database to allow selection based upon individual Banff criteria of rejection.  This will provide the foundation for a novel and powerful teaching tool.

Last Modified: Thu Jun 18 10:14:08 EDT 2009