Keiichi Yoshimoto

Distinct expression of CCR1 and CCR5 in glomerular and interstitial lesions of human glomerular diseases.

We investigated the presence of CCR1- and CCR5-positive cells immunohistochemically in the kidneys of 38 patients with several renal diseases, including 13 crescentic glomerulonephritis patients. In addition, we determined cell phenotypes of CCR1- and CCR5-positive cells using a dual immunostaining technique. Urinary levels of their ligands, for CCR1 and CCR5; macrophage inflammatory protein (MIP)-1α, MIP-1β and regulated upon activation in normal T cells expressed and secreted (RANTES) were evaluated by enzyme-linked immunosorbent assay. CCR1- and CCR5-positive cells were detected in both glomeruli and interstitium of the diseased kidneys. Using a dual immunostaining technique, these positive cells were CD68-positive macrophages (MΦ) and CD3-positive T cells. The number of CCR1-positive cells in glomeruli was correlated with urinary levels of MIP-1α. The number of CCR1-positive cells in the interstitium was correlated with both urinary MIP-1α and RANTES levels. CCR1-positive cells in the interstitium remained after glucocorticoid therapy, most of which were MΦ, and were correlated with the intensity of interstitial fibrosis and tubular atrophy. Glomerular CCR5-positive cells were well correlated with extracapillary lesions and urinary MIP-1α levels, while interstitial CCR5-positive cells, mainly CD3-positive T cells, were correlated with interstitial lesions and urinary RANTES levels. Renal CCR5-positive cells were dramatically decreased during convalescence induced by glucocorticoids. These results suggest that chemokine receptor signaling may be pivotal for human renal diseases through the recruitment and activation of MΦ and T cells; CCR5-positive cells may participate in glomerular lesions including extracapillary lesions via MIP-1α and in interstitial lesions via RANTES. CCR1 may be involved in interstitial lesions in resolving phase after glucocorticoid therapy.

Upregulation of Fractalkine in Human Crescentic Glomerulonephritis

Background/Aim: To evaluate the importance of fractalkine, a novel member of the CX3C chemokine, and natural killer (NK) cells in human crescentic glomerulonephritis, we determined the presence of fractalkine in the diseased kidneys immunohistochemically, and the correlation among fractalkine, NK cells and the degree of renal damage. Methods: Twenty-three patients (13 males and 10 females) with primary or secondary crescentic glomerular disease were evaluated in this study. Fractalkine and CD16-positive cells including NK cells were detected immunohistochemically. Results: Fractalkine-positive cells were detected in the interstitium of 23 patients with crescentic glomerulonephritis, while they were not detected in the glomeruli. In addition, CD16-positive cells were detected in both the glomeruli (1.3 ± 0.2/glomerulus) and interstitium (1.3 ± 0.2/visual field). The number of fractalkine-positive cells in the interstitium correlated with the number of CD16-positive cells before glucocorticoid therapy (r = 0.43, p = 0.047, n = 23). The number of fractalkine-positive cells in the interstitium before glucocorticoid therapy (0.2 ± 0.1/visual field) decreased after therapy (0.1 ± 0.1/visual field, p = 0.050) in 11 cases tested. The number of CD16-positive cells in the diseased kidneys did not change after glucocorticoid therapy. Conclusion: These results suggest that the local production of fractalkine may explain the presence of CD16-positive cells including NK cells, which may participate in the interstitial lesions of human crescentic glomerulonephritis before corticoid therapy.

CD68 and MCP-1/CCR2 expression of initial biopsies reflect the outcomes of membranous nephropathy.

Background: A considerable diversity of prognosis is seen with idiopathic membranous nephropathy (IMN). The initial factors affecting long-term outcome remain unclear. Methods: We studied retrospectively 30 patients with IMN who had been followed up for at least 5 years, or until end-stage renal failure (ESRF). We analyzed the prognostic factors of ESRF in the first renal biopsies; these factors included presence of tubulointerstitial lesions and foam cells, as well as expression of CD68, monocyte chemoattractant protein-1 (MCP-1), its cognate receptor chemokine receptor 2 (CCR2) and α-smooth muscle actin. Results: The patients who developed ESRF showed higher percentages of glomerular segmental sclerosis, interstitial MCP-1 expression, CCR2- or CD68-positive monocyte/macrophages and foam cells in the interstitium, and these proved on multivariate analysis to be independent risk factors for ESRF. Finally, ESRF was characterized by the presence of ten interstitial CD68-positive cells per visual field at 200× magnification (hazard ratio 4.096, CI 1.271–15.029, p < 0.001). Conclusions: Our results suggested that an interstitial infiltration of CD68-positive cells accompanied by MCP-1/CCR2 expression is the most significant indicator of ESRF in IMN.

Matrix metalloproteinase-2 (MMP-2) and membrane-type 1 MMP (MT1-MMP) affect the remodeling of glomerulosclerosis in diabetic OLETF rats

BACKGROUND We reported previously that diabetic glomerular nodular-like lesions were formed during the reconstruction process of mesangiolysis. However, the precise mechanism has yet to be elucidated. Here, we investigated the roles of matrix metalloproteinase (MMP)-2, which is activated from proMMP-2 by membrane-type (MT)-MMP in the sclerotic and endothelial cell injury process of a type II diabetic model, Otsuka Long-Evans Tokushima Fatty (OLETF) rats. METHODS Monocrotaline (MCT) or saline only was injected three times every 4 weeks in 36-week-old OLETF rats and control Long-Evans Tokushima Otsuka rats. Glomerular expression and enzymatic activity of MMP-2 and MT1-MMP were assessed by immunohistochemistry, gelatin zymography of cultured glomerular supernatants, in situ enzymatic detection and reverse transcription-polymerase chain reaction. RESULTS Mesangial matrix increased in OLETF rats. In addition, mesangiolysis and nodular-like mesangial expansion were observed only in MCT-injected endothelial injured OLETF rats. MMP-2 and MT1-MMP proteins increased in the expanded mesangial lesions in OLETF rats. Gelatin zymography revealed an increase in 62-kDa activated MMP-2 in the culture supernatants of isolated glomeruli from OLETF rats. In situ enzymatic activity of MMP in the mesangial areas was also detected in 50-week-old MCT-injected OLETF rats. CONCLUSION These results suggest that MMP-2 and MT1-MMP are produced and activated in glomeruli through the progression of diabetic nephropathy and may have some effect on the remodeling of the glomerular matrix in diabetic nephropathy.

Electron-dense deposition patterns and the outcomes of idiopathic membranous nephropathy in Japanese

 A considerable diversity in prognosis is seen with membranous nephropathy (MN). In terms of pathological findings, the presence of tubulointerstitial lesions was emphasized as a poor prognostic factor. However, the glomerular factors affecting the long-term outcome of idiopathic human MN have remained unclear. We reviewed the initial clinicopathological factors affecting the primary and secondary outcomes in 105 patients with primary MN, as well as reviewing previous reports. Based on electron microscopic (EM) findings, we could divide patients into two subtypes and one subgroup; i.e., homogeneous type with a synchronous phase of electron-dense deposits, with large dense deposits (deep subgroup) and heterogeneous type with various phases of dense deposits. The homogeneous type showed no endstage renal failure, and had earlier remission as compared with the heterogeneous type. For the secondary outcome, heterogeneous type and deep subgroup were also independent risk factors. However, there was no significant difference in the final primary or secondary outcome for any treatment subgroups. These results indicated that our category of EM findings was a beneficial marker of the primary and secondary outcomes in MN; the homogeneous type of MN with synchronous phase of electron-dense deposits (except for the “deep” subgroup) had a good outcome.