Repeated human leukocyte antigens eplets, importance of typing the partner.

INTRODUCTION: Antibody-mediated rejection (AMR) is the most common cause of immune-mediated allograft failure after kidney transplant and impacts allograft survival. Previous sensitization is a major risk factor for development of donor specific antibodies (DSA). AMR can have a wide range of clinical features such as impaired kidney function, proteinuria/hypertension or can be subclinical. HLA molecules have specific regions of antigens binding antibodies called epitopes and eplets are considered essential components responsible for immune recognition. We present a patient with subclinical AMR 1 week post transplantation. CASE REPORT: A 48-year-old, caucasian woman with end-stage kidney disease (ESKD) secondary to autosomal dominant polycystic kidney disease (ADPKD) on peritoneal dialysis was registered in deceased donor waitlist. She was a hypersensitized patient from 3 prior pregnancies with a calculated panel reactive antibody of 93,48%. She was transplanted through kidney paired exchange donation with no evidence of DSA pre transplantation. Surgery and post-op were unremarkable with excellent and immediate graft function. Per protocol DSA levels on the 5th day was DR1 of 3300 MFI, with an increase in MFI by day 13 with 7820 MFI and a new B41 1979MFI. Allograft kidney biopsy findings were diagnostic of AMR and she was treated with immunoglobulin and plasmapheresis. As early onset AMR post transplantation was observed an anamnestic response was hypothesized from a previous exposure to allo-HLA. We decided to type her husband, her son's father, which was presented with DSA. Mismatch eplet analysis revealed a shared 41 T and 67LQ eplets between the donor and husband, responsible for the reactivity and new HLA class I B41 and HLA class II DR1 DSA, respectively. DISCUSSION: Shared eplets between the patient husband and donor was responsible for the alloimmune response and early development of DSAs. This case highlights the importance of early monitoring DSA levels in highly sensitized patients after transplant in order to promptly address and lower inflammatory damage. Mismatch eplet analysis can provide a thorough and precise evaluation of immune compatibility providing a useful technique to immune risk stratification, donor selection and post-transplant immunosuppressive therapy and monitoring.

Role of chemokines, innate and adaptive immunity.

Polycystic Kidney Disease (PKD) triggers a robust immune system response including changes in both innate and adaptive immunity. These changes involve immune cells (e.g., macrophages and T cells) as well as cytokines and chemokines (e.g., MCP-1) that regulate the production, differentiation, homing, and various functions of these cells. This review is focused on the role of the immune system and its associated factors in the pathogenesis of PKDs as evidenced by data from cell-based systems, animal models, and PKD patients. It also highlights relevant pre-clinical and clinical studies that point to specific immune system components as promising candidates for the development of prognostic biomarkers and therapeutic strategies to improve PKD outcomes.

Tubular STAT3 Limits Renal Inflammation in Autosomal Dominant Polycystic Kidney Disease.

BACKGROUND: The inactivation of the ciliary proteins polycystin 1 or polycystin 2 leads to autosomal dominant polycystic kidney disease (ADPKD). Although signaling by primary cilia and interstitial inflammation both play a critical role in the disease, the reciprocal interactions between immune and tubular cells are not well characterized. The transcription factor STAT3, a component of the cilia proteome that is involved in crosstalk between immune and nonimmune cells in various tissues, has been suggested as a factor fueling ADPKD progression. METHOD: To explore how STAT3 intersects with cilia signaling, renal inflammation, and cyst growth, we used conditional murine models involving postdevelopmental ablation of Pkd1, Stat3, and cilia, as well as cultures of cilia-deficient or STAT3-deficient tubular cell lines. RESULTS: Our findings indicate that, although primary cilia directly modulate STAT3 activation in vitro, the bulk of STAT3 activation in polycystic kidneys occurs through an indirect mechanism in which primary cilia trigger macrophage recruitment to the kidney, which in turn promotes Stat3 activation. Surprisingly, although inactivating Stat3 in Pkd1-deficient tubules slightly reduced cyst burden, it resulted in a massive infiltration of the cystic kidneys by macrophages and T cells, precluding any improvement of kidney function. We also found that Stat3 inactivation led to increased expression of the inflammatory chemokines CCL5 and CXCL10 in polycystic kidneys and cultured tubular cells. CONCLUSIONS: STAT3 appears to repress the expression of proinflammatory cytokines and restrict immune cell infiltration in ADPKD. Our findings suggest that STAT3 is not a critical driver of cyst growth in ADPKD but rather plays a major role in the crosstalk between immune and tubular cells that shapes disease expression.

Cluster of differentiation 8 and programmed cell death ligand 1 expression in triple-negative breast cancer combined with autosomal dominant polycystic kidney disease and tuberous sclerosis complex: a case report.

BACKGROUND: Autosomal dominant polycystic kidney disease is defined as an inherited disorder characterized by renal cyst formation due to mutations in the PKD1 or PKD2 gene, whereas tuberous sclerosis complex is an autosomal dominant neurocutaneous syndrome caused by mutation or deletion of the TSC2 gene. A TSC2/PKD1 contiguous gene syndrome, which is caused by a chromosomal mutation that disrupts both the TSC2 and PKD1 genes, has been identified in patients with tuberous sclerosis complex and severe early-onset autosomal dominant polycystic kidney disease. The tumor tissue of patients with breast cancer with contiguous gene syndrome has a high mutation burden and produces several neoantigens. A diffuse positive immunohistochemistry staining for cluster of differentiation 8+ in the T cells of breast cancer tissue is consistent with neoantigen production due to high mutation burden. CASE PRESENTATION: A 61-year-old Japanese woman who had been undergoing dialysis for 23 years because of end-stage renal failure secondary to autosomal dominant polycystic kidney disease was diagnosed as having triple-negative breast cancer and underwent mastectomy in 2015. She had a history of epilepsy and skin hamartoma. Her grandmother, mother, two aunts, four cousins, and one brother were also on dialysis for autosomal dominant polycystic kidney disease. Her brother had epilepsy and a brain nodule. Another brother had a syndrome of kidney failure, intellectual disability, and diabetes mellitus, which seemed to be caused by mutation in the CREBBP gene. Immunohistochemistry of our patient's breast tissue showed cluster of differentiation 8 and programmed cell death ligand 1 positivity. CONCLUSIONS: Programmed cell death ligand 1 checkpoint therapy may be effective for recurrence of triple-negative breast cancer in a patient with autosomal dominant polycystic kidney disease and tuberous sclerosis complex.

CD8+ T cells modulate autosomal dominant polycystic kidney disease progression.

Autosomal dominant polycystic kidney disease (ADPKD) is the most prevalent inherited nephropathy. To date, therapies alleviating the disease have largely focused on targeting abnormalities in renal epithelial cell signaling. ADPKD has many hallmarks of cancer, where targeting T cells has brought novel therapeutic interventions. However, little is known about the role and therapeutic potential of T cells in ADPKD. Here, we used an orthologous ADPKD model, Pkd1 p.R3277C (RC), to begin to define the role of T cells in disease progression. Using flow cytometry, we found progressive increases in renal CD8+ and CD4+ T cells, correlative with disease severity, but with selective activation of CD8+ T cells. By immunofluorescence, T cells specifically localized to cystic lesions and increased levels of T-cell recruiting chemokines (CXCL9/CXCL10) were detected by qPCR/in situ hybridization in the kidneys of mice, patients, and ADPKD epithelial cell lines. Importantly, immunodepletion of CD8+ T cells from one to three months in C57Bl/6 Pkd1RC/RC mice resulted in worsening of ADPKD pathology, decreased apoptosis, and increased proliferation compared to IgG-control, consistent with a reno-protective role of CD8+ T cells. Thus, our studies suggest a functional role for T cells, specifically CD8+ T cells, in ADPKD progression. Hence, targeting this pathway using immune-oncology agents may represent a novel therapeutic approach for ADPKD.

Semaphorin 7A in circulating regulatory T cells is increased in autosomal-dominant polycystic kidney disease and decreases with tolvaptan treatment.

BACKGROUND: Semaphorin 7A (SEMA7A) is an immunomodulating protein implicated in lung and liver fibrosis. In autosomal-dominant polycystic kidney disease (ADPKD), the progressive expansion of renal cysts, inflammation, and subsequent renal fibrosis leads to end-stage renal disease (ESRD). SEMA7A may play a role in renal fibrosis and in ADPKD. METHODS: We evaluated Sema7a in a mouse model of renal fibrosis and determined the expression of SEMA7A in human ADPKD kidney. We analyzed SEMA7A expression on peripheral blood mononuclear cells (PBMCs), including CD45+ (leukocyte), CD14+(monocyte), CD4+ (T lymphocytes) and CD4+Foxp3+CD25+ [regulatory T lymphocytes (Tregs)] from 90 ADPKD patients (11 tolvaptan treated and 79 tolvaptan naïve), and 21 healthy volunteers, using a Fluorescence-Activated Cell Sorting (FACS). RESULTS: Sema7a is required for renal fibrosis. SEMA7A shows robust expression in ADPKD kidneys, localizing to cysts derived from distal tubules. SEMA7A is higher in circulating monocytes, but unchanged in CD4+ lymphocytes in ADPKD patients. The SEMA7A increase was detected early (stage 1 CKD) and seemed more prominent in patients with smaller kidneys (p = 0.09). Compared to tolvaptan-naïve ADPKD patients, those treated with tolvaptan showed reduced SEMA7A expression on monocytes, T lymphocytes, and Tregs, although the number of PBMCs was unchanged. After 1 month of tolvaptan treatment, SEMA7A expression on Tregs decreased. CONCLUSIONS: SEMA7A shows potential as both a therapeutic target in mammalian kidney fibrosis and as a marker of inflammation in ADPKD patients. SEMA7A expression was lower after tolvaptan treatment, which may reflect drug efficacy.

Toll-Like Receptors in the Progression of Autosomal Dominant Polycystic Kidney Disease.

Autosomal dominant polycystic kidney disease (ADPKD) is the most common hereditary cause of chronic kidney disease. The intriguing role of innate immune system and inflammation become a target for potential therapeutic approach to slow progression. When toll-like receptors (TLRs) signaling and their receptors activate, they start a cascade of intracellular signaling that induces the production of the inflammatory cytokines and chemokines. Thus, we aim to investigate the association of TLRs between progression of ADPKD. Ninety ADPKD patients and ninety matched controls were enrolled this prospective study and were followed during 3 years. TLR-2 and TLR-4 gene polymorphisms and expressions were measured. Hypertension was diagnosed with ambulatory blood pressure monitoring. Rapid progression was defined as sustained decline in estimated glomerular filtration rate (eGFR) of more than 5 mL/min per 1.73 m2 per year. TLR-4Asp299Gly polymorphisms were significantly different between patient and control group (P < 0.05). Also, TLR-2 and TLR-4 gene expressions were significantly different between the ADPKD patients and the control subjects (P < 0.05). The expression levels of both TLR-2 and TLR-4 were found to be higher in the rapid progression groups comparing the slow progression group (P < 0.05). TLR-2 gene expression, hypertension and uric acid were found to be independent risk factors in identifying rapid progression in ADPKD patients. TLR-2 and TLR-4 gene expressions are associated with rapid progression in ADPKD patients. TLRs may play a role in the progression of ADPKD.

Evaluation of Th17 pathway in the diagnosis of autosomal dominant polycystic kidney disease.

INTRODUCTION: Current assessment tools of autosomal dominant polycystic kidney disease (ADPKD) diagnosis are challenging. This study evaluated the possible application of assessment of interleukin (IL)-17-related cytokines and the circulatory T helper 17 cells in the diagnosis of ADPKD. MATERIALS AND METHODS: Enrolling 54 ADPKD patients and 54 healthy individuals, we measured serum and urine levels of IL-6, IL-17, IL-23, and transforming growth factor-ß and the peripheral blood frequency of T helper 17 cells through flowcytometry. We computed sensitivity and specificity of each inflammatory marker as well as their different combinations using the receiver operating characteristic curve and discriminant function analysis. RESULTS: The mean serum and urine levels of IL-17 and IL-23 as well as urine levels of IL-6 were higher in ADPKD patients compared to the healthy controls (P < .001). There was no significant difference in the number of T helper 17 cells between the two groups. Among different combinations of the inflammatory markers, the serum IL-17 was the best factor in the diagnosis of ADPKD with a sensitivity as well as specificity of 100%. CONCLUSIONS: It is likely that T helper 17 pathway is involved in the pathogenesis of ADPKD; therefore, it may be beneficial if such a pathway be considered in its diagnosis.

Excessive activation of the alternative complement pathway in autosomal dominant polycystic kidney disease.

OBJECTIVES: The complement system is involved in many immune complex-mediated kidney diseases, yet its role in the pathogenesis of autosomal dominant polycystic kidney disease (ADPKD) has not been examined in detail. METHODS AND RESULTS: Screening of the glycoproteome of urine samples from ADPKD patients revealed that levels of complement factor B (CFB), serpin peptidase inhibitor, complement component 1 inhibitor (SERPING1) and complement component 9 (C9) increased, whereas complement component 1, r subcomponent-like (C1RL), CD55 and CD59 levels decreased with disease progression. Immunostaining and Western blot analysis confirmed the enhanced expression of CFB and C9 in cystic kidneys from ADPKD patients. Immunostaining also showed that the expressions of CFB and C9 in renal biopsy tissues from patients with other types of chronic kidney disease were lower than in tissues from ADPKD patients. The effect of the complement inhibitor rosmarinic acid (RMA) was evaluated in Pkd1(-/-) mice and Han:SPRD Cy/+ rats. Compared with vehicle-treated Pkd1(-/-) animals, RMA-treated mice had significantly lower serum creatinine (-50%) and blood urea nitrogen (-78%) levels, two kidneys/body weight ratio (-60%) and renal cystic index (-60%). Similar results were found in Cy/+ rats. Lower numbers of Ki67-positive nuclei and inflammatory cells and reduced fibrosis were observed in both animal models upon treatment with RMA. CONCLUSIONS: These results suggest that excessive activation of the alternative complement pathway is associated with ADPKD progression, probably mediated by cyst-lining epithelial cell proliferation, tubulointerstitial inflammatory cell infiltration and fibrosis. Targeting the complement system might represent a new therapeutic strategy for ADPKD.

Cyst expansion and regression in a mouse model of polycystic kidney disease.

Autosomal-dominant polycystic kidney disease is characterized by progressive cyst formation and fibrosis in the kidneys. Here we describe an orthologous Pkd1(nl,nl) mouse model, with reduced expression of the normal Pkd1 transcript, on a fixed genetic background of equal parts C57Bl/6 and 129Ola/Hsd mice (B6Ola-Pkd1(nl,nl)). In these mice, the first cysts develop from mature proximal tubules around birth. Subsequently, larger cysts become visible at day 7, followed by distal tubule and collecting duct cyst formation, and progressive cystic enlargement to develop into large cystic kidneys within 4 weeks. Interestingly, cyst expansion was followed by renal volume regression due to cyst collapse. This was accompanied by focal formation of fibrotic areas, an increased expression of genes involved in matrix remodeling and subsequently an increase in infiltrating immune cells. After an initial increase in blood urea within the first 4 weeks, renal function remained stable over time and the mice were able to survive up to a year. Also, in kidneys of ADPKD patients collapsed cysts were observed, in addition to massive fibrosis and immune infiltrates. Thus, B6Ola-Pkd1(nl,nl) mice show regression of cysts and renal volume that is not accompanied by a reduction in blood urea levels.

Macrophages promote polycystic kidney disease progression.

Renal M2-like macrophages have critical roles in tissue repair, stimulating tubule cell proliferation and, if they remain, fibrosis. M2-like macrophages have also been implicated in promoting cyst expansion in mouse models of autosomal dominant polycystic kidney disease (ADPKD). While renal macrophages have been documented in human ADPKD, there are no studies in autosomal recessive polycystic kidney disease (ARPKD). Here we evaluated the specific phenotype of renal macrophages and their disease-impacting effects on cystic epithelial cells. We found an abundance of M2-like macrophages in the kidneys of patients with either ADPKD or ARPKD and in the cystic kidneys of cpk mice, a model of ARPKD. Renal epithelial cells from either human ADPKD cysts or noncystic human kidneys promote differentiation of naive macrophages to a distinct M2-like phenotype in culture. Reciprocally, these immune cells stimulate the proliferation of renal tubule cells and microcyst formation in vitro. Further, depletion of macrophages from cpk mice indicated that macrophages contribute to PKD progression regardless of the genetic etiology. Thus, M2-like macrophages are two-pronged progression factors in PKD, promoting cyst cell proliferation, cyst growth, and fibrosis. Agents that block the emergence of these cells or their effects in the cystic kidney may be effective therapies for slowing PKD progression.

Macrophages promote cyst growth in polycystic kidney disease.

Polycystic kidney disease (PKD) exhibits an inflammatory component, but the contribution of inflammation to cyst progression is unknown. Macrophages promote the proliferation of tubular cells following ischemic injury, suggesting that they may have a role in cystogenesis. Furthermore, cultured Pkd1-deficient cells express the macrophage chemoattractants Mcp1 and Cxcl16 and stimulate macrophage migration. Here, in orthologous models of both PKD1 and PKD2, abnormally large numbers of alternatively activated macrophages surrounded the cysts. To determine whether pericystic macrophages contribute to the proliferation of cyst-lining cells, we depleted phagocytic cells from Pkd1(fl/fl);Pkhd1-Cre mice by treating with liposomal clodronate from postnatal day 10 until day 24. Compared with vehicle-treated controls, macrophage-depleted mice had a significantly lower cystic index, reduced proliferation of cyst-lining cells, better-preserved renal parenchyma, and improved renal function. In conclusion, these data suggest that macrophages home to cystic areas and contribute to cyst growth. Interruption of these homing and proliferative signals could have therapeutic potential for PKD.

HLA-B27 is a potential risk factor for posttransplantation diabetes mellitus in autosomal dominant polycystic kidney disease patients.

The aim of this work was to investigate HLA phenotype predisposition to posttransplantation diabetes mellitus (PTDM) in kidney transplant recipients stratified according to kidney failure etiology. Ninety-eight transplant recipient pairs with kidney grafts from the same cadaveric donor were qualified for the study. In each pair, 1 kidney was grafted to an individual with autosomal dominant polycystic kidney disease (ADPKD group) and 1 to recipient with a different cause of kidney failure (non-ADPKD group). All class II HLA antigens were determined with the PCR-SSP molecular method. To identify class I HLA molecules we used both molecular and serologic methods. Diabetes was diagnosed according to the American Diabetes Association criteria. The posttransplantation observation period was 12 months. In the ADPKD group, HLA-B27 was more common in PTDM than non-PTDM patients; 31.6% versus 11.4% (P = .069). The difference achieved significance when comparing insulin-treated with non-insulin-treated patients (44.4% vs 12.4%; P = .029). In the non-ADPKD group, HLA-A28 and HLA-B13 were observed more frequently in patients with PTDM than in recipients without diabetes (22.2% vs 2.5% [P = .0099] and 22.2% vs 3.8% [P = .020]). All of these associations were significant upon multivariate analysis. HLA-B27 allele is a factor predisposing ADPKD patients to insulin-dependent PTDM. Antigens predisposing to PTDM among kidney graft recipients without ADPKD include HLA-A28 and B13.

Effects of specific genes activating RAGE on polycystic kidney disease.

BACKGROUND: Autosomal-dominant polycystic kidney disease (ADPKD) is characterized by progressive cyst formation and secretion of fluid and is associated with interstitial inflammation and fibrosis, resulting in the loss of renal function. We previously generated mice overexpressing PKD2, causing progressive cyst development with an inflammatory and fibrotic phenotype in the kidneys. METHODS: To profile the gene expression related to inflammation and cystogenesis, microarray analysis was performed with kidney tissue from 6-, 12- and 18-month-old mice. Subsequently, levels and related mechanisms of selected genes, s100a8 and s100a9, were evaluated. RESULTS: S100a8 and s100a9 was upregulated more than 2-fold and differently expressed in the cystic region. Receptor of advanced glycation end product (RAGE) is a putative cell surface receptor for s100a8/a9. It was expressed in cyst-lining cells and up-regulated pro-inflammatory transcription factor NF-kappaB in transgenic mice. We also confirmed RAGE expression in ADPKD patient kidneys. It was suggested that the signaling related to proliferative cystogenesis through previous reports; therefore, we confirmed that phosphorylated-ERK and cyst formation was reduced by treatment of RAGE-siRNA. CONCLUSIONS: The results may provide important information for the expression of s100a8/a9 and RAGE, linking progressive cystogenesis with inflammation in cystic kidney.

A tumor necrosis factor-alpha-mediated pathway promoting autosomal dominant polycystic kidney disease.

Autosomal dominant polycystic kidney disease (ADPKD) is caused by heterozygous mutations in either PKD1 or PKD2, genes that encode polycystin-1 and polycystin-2, respectively. We show here that tumor necrosis factor-alpha (TNF-alpha), an inflammatory cytokine present in the cystic fluid of humans with ADPKD, disrupts the localization of polycystin-2 to the plasma membrane and primary cilia through a scaffold protein, FIP2, which is induced by TNF-alpha. Treatment of mouse embryonic kidney organ cultures with TNF-alpha resulted in formation of cysts, and this effect was exacerbated in the Pkd2(+/-) kidneys. TNF-alpha also stimulated cyst formation in vivo in Pkd2(+/-) mice. In contrast, treatment of Pkd2(+/-) mice with the TNF-alpha inhibitor etanercept prevented cyst formation. These data reveal a pathway connecting TNF-alpha signaling, polycystins and cystogenesis, the activation of which may reduce functional polycystin-2 below a critical threshold, precipitating the ADPKD cellular phenotype.

[Expression of mRNA for growth factors and cytokines in the renal artery wall of chronically rejected renal allograft]. / Ekspresja mRNA czynników wzrostu i cytokin w scianie tetnicy nerkowej przeszczepionej nerki w okresie przewleklego odrzucania.

The vascular hallmark of chronic rejection (CR), as well as of atherosclerosis, is initial hyperplasia. It results from migration and proliferation of vascular smooth muscle cell and increased deposition of extracellular matrix proteins. A possible mechanism responsible for formation of neointima is the release of growth factors and cytokines, such as: transforming growth factor beta (TGF-beta), tumour necrosis factor alfa (TNF-alpha), interleukin 1 (IL-1) and interleukin 6 (IL-6). The expression of these factors in the renal artery wall of chronically rejected allografts was quantified. The renal artery samples were obtained from patients with chronic renal allograft rejection, undergoing graftectomy (n = 11) and patients with autosomal dominant polycystic kidney disease (ADPKD), undergoing nephrectomy (n = 4). Total RNA was isolated and the expression of mRNA for TGF-beta, TNF-alpha, IL-1 and IL-6 was measured using a real time PCR. In patients with CR the expression levels of TGF-beta, TNF-alpha and IL-1 mRNA were higher than in control group. No difference between groups was detected for IL-6. In both groups a correlation was detected between age and TGF-beta expression. The increased expression of TGF-beta, TNF-alpha and IL-1 may be a key factor in the neointimal formation and pathogenesis of CR. The increase in the TGF-b expression with age might be a protective mechanism in atherosclerosis.

Expression of differentiation antigens and growth-related genes in normal kidney, autosomal dominant polycystic kidney disease, and renal cell carcinoma.

Cellular differentiation and mRNA levels of genes involved in kidney growth were investigated in normal kidney cells, cyst-lining epithelial cells of polycystic kidney disease, and renal carcinoma cells (RCC). All cells comparatively studied exhibited an antigenic phenotype of proximal tubular cells as shown by the expression of a panel of brush border membrane enzymes and kidney-associated cell surface antigens. The epithelial developmental antigen Exo-1 was expressed in 50% to 80% of cyst-lining epithelia in polycystic kidney tissue and in 20% to 30% of polycystic kidney cells cultured in vitro. Normal kidney cells and RCC were negative under identical culture conditions. The expression of antigen Exo-1 is associated with hyperproliferation in an epithelial tissue compartment composed of cells which have not yet reached their terminal differentiation state. Increased amounts of mRNA of the growth factor receptor system of epidermal growth factor (EGF) receptor and its ligand transforming growth factor (TGF)-alpha were associated with the malignant phenotype of RCC. Increased expression of EGF receptor and TGF-alpha, although less prominent, were also observed in polycystic kidney cells compared with normal kidney cells. In conclusion, the expression of Exo-1 in cyst-lining epithelial cells of autosomal dominant polycystic kidney disease (ADPKD) and the altered regulation of TGF-alpha and EGF receptor in these cells contribute to the hypothesis that hyperproliferation is an underlying pathogenic mechanism of ADPKD.