scholarly journals BK Polyomavirus: Clinical Aspects, Immune Regulation, and Emerging Therapies

2017 ◽  
Vol 30 (2) ◽  
pp. 503-528 ◽  
Author(s):  
George R. Ambalathingal ◽  
Ross S. Francis ◽  
Mark J. Smyth ◽  
Corey Smith ◽  
Rajiv Khanna
Keyword(s):  
Hemorrhagic Cystitis ◽  
Management Strategies ◽  
Antiviral Agents ◽  
Diagnostic Tools ◽  
Clinical Aspects ◽  
Hematopoietic Stem ◽  
Renal Tubular Cells ◽  
Bk Polyomavirus ◽  
Renal Tubular ◽  
Host Virus Interactions

SUMMARY BK polyomavirus (BKV) causes frequent infections during childhood and establishes persistent infections within renal tubular cells and the uroepithelium, with minimal clinical implications. However, reactivation of BKV in immunocompromised individuals following renal or hematopoietic stem cell transplantation may cause serious complications, including BKV-associated nephropathy (BKVAN), ureteric stenosis, or hemorrhagic cystitis. Implementation of more potent immunosuppression and increased posttransplant surveillance has resulted in a higher incidence of BKVAN. Antiviral immunity plays a crucial role in controlling BKV replication, and our increasing knowledge about host-virus interactions has led to the development of improved diagnostic tools and clinical management strategies. Currently, there are no effective antiviral agents for BKV infection, and the mainstay of managing reactivation is reduction of immunosuppression. Development of immune-based therapies to combat BKV may provide new and exciting opportunities for the successful treatment of BKV-associated complications.

scholarly journals Non-permissive human conventional CD1c+ dendritic cells enable trans-infection of human primary renal tubular epithelial cells and protect BK polyomavirus from neutralization

2020 ◽  
Author(s):  
Mathieu Sikorski ◽  
Flora Coulon ◽  
Cécile Peltier ◽  
Cécile Braudeau ◽  
Alexandra Garcia ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Graft Loss ◽  
Endocytic Pathway ◽  
Cell Transplant ◽  
Post Transplantation ◽  
Hematopoietic Stem ◽  
Human Virus ◽  
Bk Polyomavirus ◽  
Renal Tubular

AbstractThe BK polyomavirus (BKPyV) is a ubiquitous human virus that persists in the renourinary epithelium. Immunosuppression can lead to BKPyV reactivation in the first year post-transplantation in kidney (KTR) and hematopoietic stem cell transplant recipients. In KTR, persistent DNAemia has been correlated to the occurrence of polyomavirus-associated nephropathy (PVAN) that can lead to graft loss if not properly controlled. Based on recent observations that conventional dendritic cells (cDC) specifically infiltrate PVAN lesions, we hypothesized that those cells could play a role in BKPyV infection. We first demonstrated that monocyte-derived DC (MDDC), an in vitro model for mDC, captured BKPyV particles through an unconventional GRAF-1 endocytic pathway. Neither BKPyV particles nor BKPyV-infected cells were shown to activate MDDC. Endocytosed virions were efficiently transmitted to permissive cells and shown to be protected from the antibody-mediated neutralization. Finally, we demonstrated that freshly isolated CD1c+ mDC from the blood and kidney parenchyma behaved similarly to MDDC thus extending our results to cells of clinical relevance. This study sheds light on a potential unprecedented CD1c+ mDC involvement in the BKPyV infection as a promoter of viral spreading.

scholarly journals Brincidofovir (CMX001) Inhibits BK Polyomavirus Replication in Primary Human Urothelial Cells

2015 ◽  
Vol 59 (6) ◽  
pp. 3306-3316 ◽  
Author(s):  
Garth D. Tylden ◽  
Hans H. Hirsch ◽  
Christine Hanssen Rinaldo
Keyword(s):  
Hemorrhagic Cystitis ◽  
Membrane Integrity ◽  
Mitochondrial Activity ◽  
Target Cells ◽  
Urothelial Cells ◽  
Late Gene Expression ◽  
Cytotoxic Effects ◽  
Hematopoietic Stem ◽  
Bk Polyomavirus ◽  
Renal Tubule Cell

ABSTRACTBK polyomavirus (BKPyV)-associated hemorrhagic cystitis (PyVHC) complicates 5 to 15% of allogeneic hematopoietic stem cell transplantations. Targeted antivirals are still unavailable. Brincidofovir (BCV; previously CMX001) has shown inhibitory activity against diverse viruses, including BKPyV in a primary human renal tubule cell culture model of polyomavirus-associated nephropathy. We investigated the effects of BCV in BKPyV-infected and uninfected primary human urothelial cells (HUCs), the target cells of BKPyV in PyVHC. The BCV concentrations causing 50 and 90% reductions (EC50and EC90) in the number of intracellular BKPyV genome equivalents per cell (icBKPyV) were 0.27 μM and 0.59 μM, respectively. At 0.63 μM, BCV reduced viral late gene expression by 90% and halted progeny release. Preinfection treatment for only 24 h reduced icBKPyV similarly to treatment from 2 to 72 h postinfection, while combined pre- and postinfection treatment suppressed icBKPyV completely. After investigating BCV's effects on HUC viability, mean selectivity indices at 50 and 90% inhibition (SI50and SI90) calculated for cellular DNA replication were 2.7 and 2.9, respectively, those for mitochondrial activity were 8.9 and 10.4, those for total ATP were 8.6 and 8.2, and those for membrane integrity were 25.9 and 16.7. The antiviral and cytostatic effects, but less so the cytotoxic effects, were inversely related to cell density. The cytotoxic effects at concentrations of ≥10 μM were rapid and likely related to BCV's lipid moiety. After carefully defining the antiviral, cytostatic, and cytotoxic properties of BCV in HUCs, we conclude that a preemptive or prophylactic approach in PyVHC is likely to give the best results.

scholarly journals Permissive effect of GSK3β on profibrogenic plasticity of renal tubular cells in progressive chronic kidney disease

2021 ◽  
Vol 12 (5) ◽  
Author(s):  
Bohan Chen ◽  
Pei Wang ◽  
Xianhui Liang ◽  
Chunming Jiang ◽  
Yan Ge ◽  
...  
Keyword(s):  
Chronic Kidney Disease ◽  
Kidney Disease ◽  
Renal Fibrosis ◽  
Binding Protein ◽  
Renal Tubules ◽  
Genetic Ablation ◽  
Renal Tubular Cells ◽  
Renal Tubular ◽  
Renal Fibrogenesis ◽  
Tgf Β1

AbstractRenal tubular epithelial cells (TECs) play a key role in renal fibrogenesis. After persistent injuries that are beyond self-healing capacity, TECs will dedifferentiate, undergo growth arrest, convert to profibrogenic phenotypes, and resort to maladaptive plasticity that ultimately results in renal fibrosis. Evidence suggests that glycogen synthase kinase (GSK) 3β is centrally implicated in kidney injury. However, its role in renal fibrogenesis is obscure. Analysis of publicly available kidney transcriptome database demonstrated that patients with progressive chronic kidney disease (CKD) exhibited GSK3β overexpression in renal tubulointerstitium, in which the predefined hallmark gene sets implicated in fibrogenesis were remarkably enriched. In vitro, TGF-β1 treatment augmented GSK3β expression in TECs, concomitant with dedifferentiation, cell cycle arrest at G2/M phase, excessive accumulation of extracellular matrix, and overproduction of profibrotic cytokines like PAI-1 and CTGF. All these profibrogenic phenotypes were largely abrogated by GSK3β inhibitors or by ectopic expression of a dominant-negative mutant of GSK3β but reinforced in cells expressing the constitutively active mutant of GSK3β. Mechanistically, GSK3β suppressed, whereas inhibiting GSK3β facilitated, the activity of cAMP response element-binding protein (CREB), which competes for CREB-binding protein, a transcriptional coactivator essential for TGF-β1/Smad signaling pathway to drive TECs profibrogenic plasticity. In vivo, in mice with folic acid-induced progressive CKD, targeting of GSK3β in renal tubules via genetic ablation or by microdose lithium mitigated the profibrogenic plasticity of TEC, concomitant with attenuated interstitial fibrosis and tubular atrophy. Collectively, GSK3β is likely a pragmatic therapeutic target for averting profibrogenic plasticity of TECs and improving renal fibrosis.

scholarly journals Hypoxic mesenchymal stem cells ameliorate acute kidney ischemia-reperfusion injury via enhancing renal tubular autophagy

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Wei-Cheng Tseng ◽  
Pei-Ying Lee ◽  
Ming-Tsun Tsai ◽  
Fu-Pang Chang ◽  
Nien-Jung Chen ◽  
...  
Keyword(s):  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Renal Recovery ◽  
Trophic Factors ◽  
Left Renal Artery ◽  
Renal Tubular Cells ◽  
Cell Based Therapy ◽  
Renal Tubular

Abstract Background Acute kidney injury (AKI) is an emerging global healthcare issue without effective therapy yet. Autophagy recycles damaged organelles and helps maintain tissue homeostasis in acute renal ischemia-reperfusion (I/R) injury. Hypoxic mesenchymal stem cells (HMSCs) represent an innovative cell-based therapy in AKI. Moreover, the conditioned medium of HMSCs (HMSC-CM) rich in beneficial trophic factors may serve as a cell-free alternative therapy. Nonetheless, whether HMSCs or HMSC-CM mitigate renal I/R injury via modulating tubular autophagy remains unclear. Methods Renal I/R injury was induced by clamping of the left renal artery with right nephrectomy in male Sprague-Dawley rats. The rats were injected with either PBS, HMSCs, or HMSC-CM immediately after the surgery and sacrificed 48 h later. Renal tubular NRK-52E cells subjected to hypoxia-reoxygenation (H/R) injury were co-cultured with HMSCs or treated with HMSC-CM to assess the regulatory effects of HSMCs on tubular autophagy and apoptosis. The association of tubular autophagy gene expression and renal recovery was also investigated in patients with ischemic AKI. Result HMSCs had a superior anti-oxidative effect in I/R-injured rat kidneys as compared to normoxia-cultured mesenchymal stem cells. HMSCs further attenuated renal macrophage infiltration and inflammation, reduced tubular apoptosis, enhanced tubular proliferation, and improved kidney function decline in rats with renal I/R injury. Moreover, HMSCs suppressed superoxide formation, reduced DNA damage and lipid peroxidation, and increased anti-oxidants expression in renal tubular epithelial cells during I/R injury. Co-culture of HMSCs with H/R-injured NRK-52E cells also lessened tubular cell death. Mechanistically, HMSCs downregulated the expression of pro-inflammatory interleukin-1β, proapoptotic Bax, and caspase 3. Notably, HMSCs also upregulated the expression of autophagy-related LC3B, Atg5 and Beclin 1 in renal tubular cells both in vivo and in vitro. Addition of 3-methyladenine suppressed the activity of autophagy and abrogated the renoprotective effects of HMSCs. The renoprotective effect of tubular autophagy was further validated in patients with ischemic AKI. AKI patients with higher renal LC3B expression were associated with better renal recovery. Conclusion The present study describes that the enhancing effect of MSCs, and especially of HMCSs, on tissue autophagy can be applied to suppress renal tubular apoptosis and attenuate renal impairment during renal I/R injury in the rat. Our findings provide further mechanistic support to HMSCs therapy and its investigation in clinical trials of ischemic AKI.

scholarly journals Human antigen R regulates hypoxia‐induced mitophagy in renal tubular cells through PARKIN/BNIP3L expressions

2021 ◽  
Author(s):  
Shao‐Hua Yu ◽  
Kalaiselvi Palanisamy ◽  
Kuo‐Ting Sun ◽  
Xin Li ◽  
Yao‐Ming Wang ◽  
...  
Keyword(s):  
Tubular Cells ◽  
Human Antigen R ◽  
Renal Tubular Cells ◽  
Renal Tubular
Sign in / Sign up

Export Citation Format

Share Document