-
[show abstract]
[hide abstract]
ABSTRACT: Pericytes are cells of mesenchymal origin that are intimately involved in the development and stabilization of vascular networks. Novel studies of their role in inflammation have identified that pericytes are not only major contributors to the activated matrix depositing myofibroblast populations seen in progressive renal fibrosis but perhaps even more importantly, the detachment of renal pericytes from the vasculature contributes to the microvasculature rarefaction and subsequent hypoxia associated with chronic kidney disease. In this review, our current understanding of the functioning of renal pericytes will be considered and set in the context of the wider literature that is currently available on this neglected population of cells.
Nephrology Dialysis Transplantation 05/2012; 27(6):2149-55. · 3.40 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Stromal fibroblasts are the primary cells of the kidney that produce fibrotic matrix. CD248 is a stromal marker expressed on fibroblasts and pericytes within the human kidney. Here, we tested whether CD248 expression in the kidney colocalizes with fibrosis and if it is associated with known determinants of chronic kidney disease (CKD). CD248 expression was located and quantified in situ by immunohistochemistry in kidney biopsies from 93 patients with IgA nephropathy and compared with 22 archived biopsies encompassing normal kidney tissue as control. In normal kidney tissue, CD248 was expressed by resident pericytes, stromal fibroblasts, and was upregulated in human CKD. The expression was linked to known determinants of renal progression. This relationship was maintained in a multivariate analysis with CD248 expression linked to renal survival. CD248 was expressed by a population of α-smooth muscle actin (SMA)(+) myofibroblasts and α-SMA(-) stromal cells but not expressed on CD45(+) leukocytes. Thus, CD248 defines a subset of stromal cells, including but not limited to some myofibroblasts, linked to albuminuria and tubulointerstitial damage during tissue remodeling in CKD.
Kidney International 04/2011; 80(2):199-207. · 6.61 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Wegener's granulomatosis (WG) is a chronic, relapsing, systemic autoimmune disease. Rituximab, a monoclonal antibody against human CD20, has shown promise as a novel treatment for WG. The monitoring of therapeutic B-cell 'depletion' by peripheral blood flow cytometry has been proposed to help monitor rituximab therapy. We report the case of a patient with known WG and granulomatous disease, successfully treated with rituximab, who relapsed whilst peripheral blood monitoring apparently indicated persistent B-cell depletion. Further investigations demonstrated CD20(+) B cells in tissue at sites of active disease. The implications for disease pathogenesis and clinical monitoring of disease are discussed.
Nephrology Dialysis Transplantation 07/2008; 23(9):3030-2. · 3.40 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: We have previously speculated that elevated levels of nicotinamide N-methyltransferase (NNMT), the primary catabolic enzyme of nicotinamide, may result in reduced Complex I activity in idiopathic Parkinson's disease (IPD) in two ways: (1) reduction in the levels of nicotinamide available for nicotinamide adenine dinucleotide synthesis; and (2) increased methylation of compounds such as tetrahydroisoquinolines and beta-carbolines, which are potent Complex I inhibitors. Expression of NNMT was assessed in 91 cerebella (53 IPD, 38 control) using immunohistochemistry coupled with quantitative digital image analysis. Control cerebella showed a distribution of expression ascribed to low, intermediate and high expressors with ratios of 1:2:1 categories. Expression in the parkinsonian cerebella was significantly higher than in the control group (control group median expression 17%, mean expression 16.6%, range 0-51%, standard deviation 11.4%, standard error 1.9%; IPD group median expression 46%, mean expression 53.7%, range 21-100%, standard deviation 23.4%, standard error 3.2%; P<0.0001; unpaired t-test with Welch correction (parametric) and Mann-Whitney U-test (non-parametric)). These results confirm that NNMT expression is elevated in IPD, which may ultimately lead to neurodegeneration via a reduction in Complex I activity.
Neuroscience Letters 05/2003; 342(1-2):13-6. · 2.11 Impact Factor