Session Time: 5:30pm-7:30pm
Presentation Time: 5:30pm-7:30pm
Location: Exhibit Hall E
Histopathology cannot determine whether T-cell infiltrates in renal allograft biopsies recognize donor HLA or BKV antigens. The ability of a T-cell to respond in an antigen-specific manner is encoded in the TCR sequence. Therefore, this study sought to determine if TCR NGS is a potential solution to this diagnostic conundrum.
Biopsy genomic DNA was extracted from 8 HLA-A02+ positive recipients of HLA-A01+ organs (RA2+DA1+ group) with TCMR, 3 RA2+DA1+ recipients with a history of BKVN, 6 TCMR biopsies from HLA-A01+ recipients of HLA-02+ organs (RA1+DA2+ group), and 6 RA1+DA2+ biopsies with BKVN. A TCRβ CDR3 template library was generated using 45 TCR Vβ forward primers and 13 TCR Jβ reverse primers and submitted for NGS. V- and J regions were identified in the sequencing data using the ImMunoGeneTics IMGT/Junction Analysis tool . In each sample the total number of unique TCRβ CDR3 sequences was expressed as a percentage of total sequences and assigned to different TCR-Vβ and VJ families.
RA1DA2 biopsies with TCMR showed higher utilization of V-09 compared to RA2DA1 biopsies with TCMR (2.149±0.576% vs 1.157±0.524%), indicating that TCRβ gene usage in biopsies with TCMR was dependent on recipient and donor HLA-type. Considering only biopsies with BKVN, RA1DA2 subjects showed greater utilization of V-family genes V-04, V-05, V-06, V-07, V-09 and V-27 compared to RA2DA1 subjects [see Table]. J-family genes J01-04, J01-05, J02-01, J02-03 and J02-07 exhibited the same pattern (data not shown). Thus TCRβ usage in response to BKV infection was also HLA-dependent. If all biopsies with BKVN were considered as a group, these had a lower expression of the aforementioned V-family genes compared to all biopsies with TCMR.
In conclusion, TCR Vβ and VJ gene utilization patterns (a) are dependent on both recipient and donor HLA type, and (b) can be potentially exploited to develop labortory tests that distinguish TCMR from BKVN in biopsies that are difficult to interpret by routine microscopy.
To cite this abstract in AMA style:Zeng G, Huang Y, Randhawa P. Prospects of Differentiating T-Cell Mediated Rejection (TCMR) from BK Virus Nephropathy (BKVN) Using Next Generation Sequencing (NGS) of the T-Cell Receptor (TCR) [abstract]. Am J Transplant. 2015; 15 (suppl 3). https://atcmeetingabstracts.com/abstract/prospects-of-differentiating-t-cell-mediated-rejection-tcmr-from-bk-virus-nephropathy-bkvn-using-next-generation-sequencing-ngs-of-the-t-cell-receptor-tcr/. Accessed May 28, 2020.
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