Session Time: 5:30pm-7:30pm
Presentation Time: 5:30pm-7:30pm
Location: Hall C & D
*Purpose: T cell help is essential for B cell production of antibodies to donor organ HLA. Because T cell-B cell interactions contribute to anti-allograft immunity, we reasoned that in addition to their unique gene expression patterns, acute T cell mediated rejection (ACR) and active antibody mediated rejection (AMR) must share molecular features as well. RNA-sequencing (RNA-seq) is currently the best approach for precise, unbiassed characterization of mRNA transcriptomes. PCR assays permit absolute quantification of mRNAs. We applied these powerful molecular tools to discover shared gene expression patterns between ACR and AMR.
*Methods: We performed RNA-Seq of 53 biopsy matched urinary cell specimens from 47 recipients: 22 samples matched to ACR biopsies, 7 matched to AMR biopsies, and 24 matched to biopsies with no rejection changes (NR). Bioinformatics and mechanistic relevance identified 3 mRNAs for absolute quantification via preamplification enhanced real time quantitative PCR assays (RT-QPCR). The first, Integral Membrane Protein 2A (ITM2A), is expressed on T helper cells. Signaling Lymphocyte Activation Molecule Family Member 6 (SLAMF6), a type 1 transmembrane protein expressed on NK, T, and B cells, is an important mediator of T cell-B cell interactions. IKAROS Family Zinc Finger Protein 3 (IKZF3) is a transcription factor for B cell proliferation and differentiation.
*Results: Urinary cell mRNA levels for ITM2A, SLAMF6, and IKZF3 were significantly higher in urine matched to ACR biopsies and in urine matched to AMR biopsies than in urine matched to NR biopsies. (Figure 1 A-C). Importantly, urinary cell mRNA levels for ITM2A, SLAMF6, and IKZF3 were not significantly different between urine matched to ACR biopsies and urine matched to AMR biopsies (Figure 1 D-F).
*Conclusions: We have discovered (using RNA-Seq) and verified (using RT-QPCR) mechanistically relevant mRNAs shared by kidney allograft recipients with biopsies showing ACR or AMR. The identified mRNAs and/or the proteins encoded by these mRNAs may represent novel therapeutic targets in the management of ACR and AMR.
To cite this abstract in AMA style:Dooley B, Verma A, Ding R, Li C, Snopkowski C, Yang H, Botticelli B, Albakry S, Edusei E, Muthukumar T, Lubetzky M, Dadhania D, Lee J, Elemento O, Suthanthiran M. RNA Sequencing Guided Identification of Shared mRNAs in Human Kidney Allograft Recipients with Acute T Cell Mediated Rejection or Active Antibody Mediated Rejection [abstract]. Am J Transplant. 2019; 19 (suppl 3). https://atcmeetingabstracts.com/abstract/rna-sequencing-guided-identification-of-shared-mrnas-in-human-kidney-allograft-recipients-with-acute-t-cell-mediated-rejection-or-active-antibody-mediated-rejection/. Accessed August 12, 2020.
« Back to 2019 American Transplant Congress