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In Vitro and In Vivo Assessment of T, B and Myeloid Cells Suppressive Activity and Humoral Responses from Transplant Recipients
Published on: August 12, 2017
Immune status assay (ISA): a noninvasive procedure for studying allograft rejection
Luis A Fernandez1, Masahiro Tsuchida, Eric Manthei
1Division of Transplantation, Department of Surgery, University of Wisconsin Medical School, 600 Highland Avenue, Madison, WI 53792-7375, USA.
Background:
There is a need for a simple, sensitive, noninvasive technique for monitoring graft function. We report here on a simple assay called immune status assay (ISA) that determines the status of the graft by simply examining the activation status of blood T cells.
Methods:
Graft-derived fibroblasts were used as a source of alloantigens and the recipient blood as a source of allograft-specific peripheral blood lymphocytes (PBL). PBL were added to wells containing donor or third-party graft-derived fibroblasts in the presence or absence of interleukin-2 (IL-2). On day 4 [(3)H]thymidine incorporation was quantified after the cells were incubated for 3 days at 37 degrees C, in a 5% CO(2) water-jacketed incubator. The results were analyzed using the following equation: %IL2 - /IL2+ = ((mean[(3)H]thymidine uptake in the absence of IL - 2) / (mean [(3)H]thymidine uptake in the presence of IL - 2)) x 100.
Results:
The ISA score (%IL-2 - /IL-2+) correlated strongly with the outcome of the graft, as it had a sensitivity of 82% for detecting rejections (14/17), and a specificity of 81% (30/37) for detecting non-rejections. Notably, the ISA detected immune T cell activation in the blood of graft rejecting subjects, which were not detected by currently used techniques such as mixed lymphocytes reaction.
Conclusion:
The ISA is a straightforward procedure that detects allograft rejection with high specificity and sensitivity.
