Study of Tolerant Kidney Transplant Recipients (FACTOR)

Principal Investigator

Kenneth Newell | Emory University | Atlanta, GA


Throughout North America

Study Code


Study Status



The objectives of this study are: (1) to identify patients who are functionally tolerant following kidney transplantation as well as relevant groups for comparison, (2) to enter demographic and clinical data from these patients into an electronic database thereby creating a registry of tolerant kidney transplant recipients in order to facilitate subsequent mechanistic studies, and (3) to use cutting edge research technologies to define surrogate markers of tolerance and gain new insights into immune mechanisms underlying tolerance induction in humans. The study initially was designed to compare eight immunologically distinct groups of kidney transplant recipients: tolerant group, acceptors, graft loss group, monotherapy group, standard immunotherapy group, identical twins, living donors and chronic rejectors. Due to the success of recruiting participants and the analysis of biological samples collected to date, the ongoing study is limited to the enrollment of individuals in the tolerant and monotherapy groups as well as their living donors. Comparison of the tolerant group, the standard immunotherapy group, and a group of healthy volunteers using microarrays, RT-PCR, and flow phenotyping has revealed a set of candidate genes and cell phenotypes that may be associated with tolerance.  These assays have been performed under the direction of the ITN's Tolerance Assay and Data Analysis Group. The ITN Clinical Specimen Repository Core Facility will process and bank all clinical specimens obtained for this study, with the hope that it will become a valuable resource open to the community for additional future studies of this rare cohort.

Notice: This special project of the ITN will create a world-wide registry of tolerant kidney transplant recipients to act as a resource for identifying new biological markers of kidney transplant tolerance. To initiate the effort, investigators who are aware of such patients are asked to contact Dr. Ken Newell at 404.727.2489 or


Newell KA, Asare A, Kirk AD, Gisler TD, Bourcier K, Suthanthiran M, Burlingham WJ, Marks WH, Sanz I, Lechler RI, Hernandez-Fuentes MP, Turka LA, Seyfert-Margolis VL. (2009) Identification of a B cell signature associated with renal transplant tolerance in humansJ Clin Invest, 120(6), 1836-47. DOI: 10.1172/JCI39933 PMID: 20501946 PMCID: PMC2877933 [PubMed] [Reprint]

Newell KA, Asare A, Sanz I, Wei C, Rosenberg A, Gao Z, Kanaparthi S, Asare S, Lim N, Stahly M, Howell M, Knechtle S, Kirk A, Marks WH, Kawai T, Spitzer T, Tolkoff-Rubin N, Sykes M, Sachs DH, Cosimi AB, Burlingham WJ, Phippard D, Turka LA. (2014) Longitudinal Studies of a B Cell-Derived Signature of Tolerance in Renal Transplant RecipientsAm J Transplant, 15(11), 2908-20. DOI: 10.1111/ajt.13480 PMID: 26461968 PMCID: PMC4725587 [PubMed] [Reprint]

Meeting Abstracts

Newell KA, Asare A, Kirk AD, Suthanthiran M, Burlingham WJ, Bourcier K, Marks WH, Turka LA, Seyfert-Margolis V, Gisler T. Peripheral B Cell Markers Identify Tolerant Renal Transplant Recipients. (Abstract #LB08) American Transplant Congress, Boston, MA, May 30 - Jun 3, 2009. [Abstract]

Newell KA, Burlingham WJ, Marks WH, Gisler TD, Seyfert VL, Turka LA, Suthanthiran M, Kirk AD. Preliminary Analysis of the ITN Registry of Tolerant Kidney Transplant Recipients. World Transplant Congress, Boston, MA, July 22 – 27, 2006. [Abstract]

Newell KA, Phippard D, Asare A, Burlingham WJ, Turka LA.. Refinements of the transcriptional B cell "signature" associated with clinically tolerant renal transplant recipients. (Abstract #252659) American Transplant Congress, Boston, MA, June 2-6, 2012. [Abstract]

Newell KA, Asare A, Gisler T, Turka L, Seyfert-Margolis V, Suthanthiran MS, Burlingham W, Marks W. A Unique B cell Signature Associated with Operational Tolerance. American Transplant Congress, Toronto, Canada, May 31-Jun 4, 2008. [Abstract]

Haynes LD, Jankowska-Gan E, Seyfert-Margolis VL, Newell KA, Turka LA, Asare A, Burlingham WJ, Bourcier KD. Donor Specific Regulation and B Cell Tolerance Signature in Renal Transplant Recipients. (Abstract #1578) 2010 American Transplant Congress, San Diego, CA, May 1-5, 2010. [Abstract]