Molecular diagnosis of kidney transplant failure based on urine

Abstract

In light of the organ shortage, there is a great responsibility to assess postmortal organs for which procurement has been consented and to increase the life span of transplanted organs. The former responsibility has moved many centers to accept extended criteria organs. The latter responsibility requires an exact diagnosis and, if possible, omission of the harmful influence on the transplant. We report the course of a kidney transplant that showed a steady decline of function over a decade, displaying numerous cysts of different sizes. Clinical workup excluded the most frequent causes of chronic transplant failure. The filed allocation documents mentioned the donor’s disease of oral‐facial‐digital syndrome, a rare ciliopathy, which can also affect the kidney. Molecular diagnosis was performed by culturing donor tubular cells from the recipient´s urine more than 10 years after transplantation. Next‐generation panel sequencing with DNA from tubular urinary cells revealed a novel truncating mutation in OFD1, which sufficiently explains the features of the kidney transplants, also found in the second kidney allograft. Despite this severe donor disease, lifesaving transplantation with good long‐term outcome was enabled for 5 recipients.

A noninvasive diagnostic approach to retrospective donor HLA typing in kidney transplant patients using urine

“…However, due to the invasive nature of the procedure serious complications may arise, in rare cases even resulting in the loss of the transplant. Furthermore, from our experience (this study and [15]) many standard transplant biopsies deliver very little DNA and are frequently cross‐contaminated with recipient tissue, which may be perirenal fat or recipient derived blood and immune cells. Based on STR analysis, this ‘contamination’ of donor with recipient DNA can reach approximately 50% (Fig.…”

“…The biopsy cylinder was immediately stored at À80 °C and DNA was extracted subsequently. Another option was expanding donor tubular cells from the recipients' urine as described earlier [15,16]. Human urinary Primary Tubular Cells (huPTC) were cultured over a period of 3 weeks, with two passages until a confluent 10 cm 2 culture dish was available for DNA extraction (Fig.…”

“…The technique for culturing primary tubular cells from the urine was published previously by others [14]. We have recently applied this technique to clarify the genetic background of a kidney donor more than ten years after her death [15]. Very recently another group has used this technique to introduce an interesting method of co‐culturing donor tubular cells with recipient´s T cells to monitor allogenic responses [16].…”

Hypoxia controls expression of kidney-pathogenicMUC1variants

“…The third ADTKD- MUC1 patient is a direct descendent of the individual ADTKD-0145 (family A-30) published by Wenzel et al, in whom the mutation has been confirmed ( Wenzel et al, 2018 ). Cells were cultured according to established protocols ( Keller et al, 2012 ; Wiesener et al, 2020 ). Tubular cells were exposed to HIF stabilizers (concentrations used were: DMOG 1 mM, Daprodustat 100 μM, Molidustat 100 μM, Vadadustat 100 μM, Roxadustat 100 μM or as indicated), hypoxia (1% O 2 or control conditions [20.9% O 2 , no treatment]) for 16 h.…”