Activation of HMGB1-TLR4 Pathway and Inflammasome Contribute to Enhanced Inflammatory Response in Extended Criteria and Kidneys With KDPI ≥85.

BACKGROUND: Metrics for evaluating low-quality kidneys have failed to predict outcomes or reduce the kidney refusal and discard rates. Kidneys from extended-criteria donors (ECDs) and kidneys with ≥85% kidney donor profile indexes (KDPIs) might have different sensitivities to the proinflammatory milieu generated by brain death. We aimed to identify gene expression profile differences in innate immunity pathways between low-quality and ideal kidneys. METHODS: Preimplantation kidney biopsies from ECD (n = 41) and standard-criteria donor (n = 39) were evaluated for real-time quantitative polymerase chain reaction gene expression using the TaqMan Gene Expression Array Plates system for genes Toll-like receptor-4 (TLR4), high-mobility group box 1, nuclear factor kappa beta, myeloid differentiation primary response 88, interferon (IFN)-γ, interleukin (IL)1-ß, tumor necrosis factor alpha, caspase-1 (CASP1), intercellular adhesion molecule 1, IL-10, heme oxygenase 1 hypoxia-inducible factor 1 (HIF-1), monocyte chemotactic protein 1, transforming growth factor beta 1, TIR-domain containing adapter inducing interferon-ß (TRIF), TRIF-related adaptor molecule, interferon regulatory factor 3 (IRF-3), receptor-interacting protein 1, IFNß-1, and nucleotide-binding oligomerization domain, leucine-rich repeat, and pyrin protein 3 complex. Gene expression was also evaluated in kidneys with KDPI ≥85. RESULTS: ECD biopsies showed significantly higher expression of IL-10, TLR4, high-mobility group box 1, IFN-γ, TRIF-related adapter molecule, IRF-3, HIF-1, nucleotide-binding oligomerization domain, leucine-rich repeat, and pyrin protein 3 complex, CASP1, and IL-1ß (P < 0.05) compared with standard-criteria donor biopsies. IRF-3, HIF-1, and CASP1 were exclusively upregulated in ECD kidneys. Compared with kidneys with KDPIs <85%, kidneys with KDPIs ≥85% had very similar gene transcripts as those observed in ECD kidneys, except that tumor necrosis factor alpha and monocyte chemotactic protein 1 expression was only elevated in kidneys with KDPIs ≥85%. Significant positive correlations were found between the different genes upregulated and the increase in KDPIs. CONCLUSIONS: Our results showed that TLR4 and inflammasome pathways are enhanced in low-quality kidneys and suggest that blocking of some targets might improve transplant outcomes and reduce discard rates.

Preimplantation Kidney Biopsies of Extended Criteria Donors Have a Heavier Inflammatory Burden Than Kidneys From Standard Criteria Donors.

BACKGROUND: Donors after brain death develop a systemic proinflammatory state that may predispose the kidneys to injury after transplantation. Because it is not known whether this inflammatory environment similarly affects the kidneys from expanded criteria donor (ECD) and standard criteria donors (SCD), we sought to evaluate differences in the gene expression of inflammatory cytokines in preimplantation biopsies (PIBx) from ECD and SCD kidneys. METHODS: Cytokines gene expression was measured in 80 PIBx (SCD, 52; ECD, 28) and associated with donor variables. RESULTS: Normal histology and chronic histological lesions were not different between both types of kidneys. ECD kidneys showed significant increase in the transcripts of MCP-1, RANTES, TGF-ß1, and IL-10 when compared with SCD. Kidneys presenting normal histology had similar inflammatory profile except by a higher expression of RANTES observed in ECD (P = 0.04). Interstitial fibrosis and tubular atrophy (interstitial fibrosis and tubular atrophy ≥ 1) were associated with higher expression of TGF-ß1, RANTES, and IL-10 in ECD compared with SCD kidneys. Cold ischemia time of 24 hours or longer was significantly associated with upregulation of FOXP3, MCP-1, RANTES, and IL10, whereas longer duration of donor hospitalization significantly increased gene expression of all markers. High FOXP3 expression was also associated with lower level of serum creatinine at 1 year. Donor age was not associated with any of the transcripts studied. CONCLUSIONS: PIBx of ECD exhibit a higher gene expression of inflammatory cytokines when compared with SCD kidneys. This molecular profile may be a specific ECD kidney response to brain death and may help to predict the posttransplant outcomes of ECD recipients.

Fetal microchimerism in kidney biopsies of lupus nephritis patients may be associated with a beneficial effect.

INTRODUCTION: Microchimeric male fetal cells (MFCs) have been associated with systemic lupus erythematosus, and published studies have further correlated MFC with lupus nephritis (LN). In the present study, we evaluated the frequency of MFC in the renal tissue of patients with LN. METHODS: Twenty-seven renal biopsies were evaluated: Fourteen were from women with clinical and laboratory findings of LN, and thirteen were from controls. Genomic DNA was extracted from kidney biopsies, and the male fetal DNA was quantified using real-time quantitative polymerase chain reactions for the detection of specific Y chromosome sequences. RESULTS: MFCs were detected in 9 (64%) of 14 of patients with LN, whereas no MFCs were found in the control group (P = 0.0006). No differences in pregnancy history were found between patients with LN and the control group. Significantly higher amounts of MFCs were found in patients with LN with serum creatinine ≤1.5 mg/dl. Furthermore, women with MFCs had significantly better renal function at the time of biopsy (P = 0.03). In contrast, patients with LN without MFCs presented with more severe forms of glomerulonephritis (World Health Organization class IV = 60% and class V = 40%). CONCLUSIONS: Our data indicate a high prevalence of MFCs in renal biopsy specimens from women with LN, suggesting a role for MFCs in the etiology of LN. The present report also provides some evidence that MFCs could have a beneficial effect in this disease.

Effect of stem cells seeded onto biomaterial on the progression of experimental chronic kidney disease.

Different routes for the administration of bone marrow-derived cells (BMDC) have been proposed to treat the progression of chronic renal failure (CRF). We investigated whether (1) the use of bovine pericardium (BP) as a scaffold for cell therapy would retard the progression of CRF and (2) the efficacy of cell therapy differently impacts distinct degrees of CRF. We used 2/3 and 5/6 models of renal mass reduction to simulate different stages of chronicity. Treatments consisted of BP seeded with either mesenchymal or mononuclear cells implanted in the parenchyma of remnant kidney. Renal function and proteinuria were measured at days 45 and 90 after cell implantation. BMDC treatment reduced glomerulosclerosis, interstitial fibrosis and lymphocytic infiltration. Immunohistochemistry showed decreased macrophage accumulation, proliferative activity and the expression of fibronectin and α-smooth muscle-actin. Our results demonstrate: (1) biomaterial combined with BMDC did retard the progression of experimental CRF; (2) cellular therapy stabilized serum creatinine (sCr), improved creatinine clearance and 1/sCr slope when administered during the less severe stages of CRF; (3) treatment with combined therapy decreased glomerulosclerosis, fibrosis and the expression of fibrogenic molecules; and (4) biomaterials seeded with BMDC can be an alternative route of cellular therapy.

Microscopic evidences that bone marrow mononuclear cell treatment improves sciatic nerve regeneration after neurorrhaphy.

Cell therapy constitutes a possibility for improving nerve regeneration, increasing the success of nerve repair. We evaluate the use of mononuclear cells in the regeneration of the sciatic nerve after axotomy followed by end-to-end neurorrhaphy. Forty adult male Wistar rats (250-300 g) were divided into four groups: (1) sham, (2) neurorrhaphy: the sciatic nerve was sectioned and repaired using epineural sutures, (3) culture medium: after the suture, received an injection of 10 µL of culture medium into the nerve, and (4) mononuclear cell: after the suture, a concentration of 3 × 10(6) of mononuclear cell was injected in epineurium region. Mononuclear cells were obtained from the bone marrow aspirates and separated by Ficoll-Hypaque method. The histological analyses were performed at the 4th postoperative day. The sciatic functional index, histological, and morphometric analyzes were used to evaluate nerve regeneration at the 6th postoperative week. Six rats were used for immunohistochemical analysis on the 4th postoperative day. In the group 4, on the fourth day, the histological analysis demonstrated a more accelerated degenerative process and an increase of the neurotrophic factors was observed. In the 6th week, all the morphometric results of the group 4 were statistically better compared with groups 2 and 3. There was a statistically significant improvement in the sciatic functional index for group 4 compared with groups 2 and 3. Mononuclear cells stimulated nerve regeneration, most probably by speeding up the Wallerian degeneration process as well as stimulating the synthesis of neurotrophic factors.