Expression of intercellular adhesion molecule-1 and infiltration of lymphocytes in glomeruli of patients with IgA nephropathy

Mesenchymal stem-cells' exosomes are renoprotective in postmenopausal chronic kidney injury via reducing inflammation and degeneration

Chronic kidney disease (CKD) is an important global disease its rates are increasing worldwide. CKD is caused by injuries to kidney tissue that exceeds the rate of regeneration, which with time lead to irreversible renal damage and CKD become evident. In females, diminished estrogen supply in the postmenopausal period is associated with greater risk for developing CKD. In this study we isolated exosomes from bone marrow mesenchymal stem/stromal cells (BM-MSCs) and tested their therapeutic effects on post-menopause CKD (PM-CKD) and compared their effects with BM-MSCs. The menopause model was achieved by bilateral ovariectomy in 8-months-old female albino rats, then no treatment, 2 million BM-MSCs or 100 μg of exosomes (Exo) was given intravenously in tail vein to ovariectomized rats and the study continued for 8 weeks post-ovariectomy. Changes in weight, urine volume, urine protein content, kidney function biochemical parameters (creatinine and BUN), Kidney oxidative stress (MDA), kidney antioxidant parameters (SOD, GPx and CAT), histopathological changes, immunohistochemical expression of KIM-1 and, finally, genes related to renal damage (peroxiredoxin-3, KIM-1 and ICAM-1) and inflammation (TNF-α, Cox2 and IL-6) were recorded for all study groups. Post-ovariectomy there was an increased body weight, drastic reduction of estrogen and progesterone levels, reduced urine output, increased urinary protein excretion, elevated serum creatinine and BUN, increased MDA and reduced GPx SOD, and CAT in kidney tissue, chronic inflammation, degenerative and fibrotic lesions in histopathological examination, high expression of KIM-1 immunohistochemically and changes in gene expression analyses all pointing to the development of CKD in the study rats. In the PM-CKD groups receiving BM-MSCs or Exo, the whole chronic inflammatory picture was completely reversed towards a much normal kidney structure and function. The improvements were more observable with Exo compared to BM-MSCs. Overall, our results show for the first time that exosomes isolated from BM-MSCs are more potent in reducing chronic inflammatory changes in the kidney of postmenopausal females compared to the cell-based approach using BM-MSCs. Therefore, MSCs-derived exosomes are a promising therapeutic approach for preserving postmenopausal kidney structure and function and, subsequently, should improve the quality of life of postmenopausal females.

Beneficial effects of tonsillectomy plus steroid pulse therapy on inflammatory and tubular markers in patients with IgA nephropathy

BACKGROUND

IgA nephropathy (IgAN) is the most common form of primary glomerulonephritis worldwide. Tonsillectomy plus steroid pulse therapy has been able to induce clinical remission in early-stage IgAN. However, its possible effect on systemic and local cytokines and tubular markers has not been fully investigated.

METHODS

We obtained serum and urine samples from 38 patients just before renal biopsy and third steroid pulse therapy. Markers of tubular damage such as N-acetyl-β-d-glucosaminidase, and kidney injury molecule-1 and inflammation such as interleukin (IL)-6, monocyte chemotactic protein (MCP)-1, intercellular adhesion molecule (ICAM)-1, and vascular cell adhesion molecule (VCAM)-1 were measured by immunoassay.

RESULTS

Before renal biopsy, only urinary inflammatory markers, except MCP-1, were associated with glomerular (proteinuria) and/or tubular damage markers. Proteinuria, hematuria, and estimated glomerular filtration rate dramatically improved after therapy. In addition, levels of serum IL-6 and ICAM-1 and all urinary markers declined significantly; however, serum MCP-1 and VCAM-1 levels did not. None of the urinary markers correlated with the serum inflammatory markers.

CONCLUSION

Tonsillectomy plus steroid pulse therapy for patients with IgAN might be useful for improving not only glomerular damage marker but also tubular damage markers through the improvement of local renal inflammation.

Pathogenesis and treatment of chronic kidney disease: a review of our recent basic and clinical data

Chronic kidney disease (CKD) is a worldwide public health problem that affects millions of people from all racial and ethnic groups. At end of 2013, over 300,000 Japanese patients had maintenance dialysis therapy (JSDT). In Japan, the major causes of end stage kidney disease (ESKD) are chronic glomerulonephritis (particularly IgA nephropathy), type 2 diabetic nephropathy, and hypertensive nephrosclerosis. Hypertension is a major factor driving the progression of CKD to ESKD. Since many features of the pathogenesis of IgA nephropathy are still obscure, specific treatment is not yet available. However, efforts by investigators around the world have gradually clarified different aspects of the pathogenesis and treatment of IgA nephropathy. Today, around half of all diabetic patients in Japan receive medical treatment. Type 2 diabetic nephropathy is one of the major long-term microvascular complications occurring in nearly 40% of Japanese diabetic patients. The pathogenesis of diabetic nephropathy involves both genetic and environmental factors. However, the candidate genes related to the initiation and progression of the disorder are still obscure in patients with diabetic nephropathy. Regarding environmental factors, the toxicity of persistent hyperglycemia, reactive oxygen species, systemic and/or glomerular hypertension, dyslipidemia and complement are considered to play an important role. The first part of this review covers the pathogenesis of IgA nephropathy and type 2 diabetic nephropathy, and combines the clinicopathological findings in patients with our research on the ddY and KKA-y mouse models (spontaneous animal models for IgA nephropathy and diabetic nephropathy, respectively). In Japan, the major renal replacement therapies (RRT) are peritoneal dialysis (PD) and hemodialysis (HD). The second part of this review focuses on PD and HD. Based on our research findings from patients and as well as from animal models, we discuss strategies for the management of patients on PD and HD.

The interaction of LFA-1 on mononuclear cells and ICAM-1 on tubular epithelial cells accelerates TGF-β1-induced renal epithelial-mesenchymal transition

The epithelial-mesenchymal transition (EMT) of renal epithelial cells (RTECs) has pivotal roles in the development of renal fibrosis. Although the interaction of lymphocyte function-associated antigen 1 (LFA-1) on leukocytes and its ligand, intracellular adhesion molecule 1 (ICAM-1), plays essential roles in most inflammatory reactions, its pathogenetic role in the EMT of RTECs remains to be clarified. In the present study, we investigated the effect of the interaction of LFA-1 on peripheral blood mononuclear cells (PBMCs) and ICAM-1 on HK-2 cells after stimulation with TGF-β(1) on the EMT of RTECs. ICAM-1 was highly expressed in HK-2 cells. After TGF-β(1) stimulation, the chemokines CCL3 and CXCL12 increased on HK-2 cells. After co-culture of PBMCs and HK-2 cells pre-stimulated with TGF-β(1) (0.1 ng/ml) (HK-2-TGF-β(1) (0.1)), the expression of the active form of LFA-1 increased on PBMCs; however, total LFA-1 expression did not change. The expression of the active form of LFA-1 on PBMCs did not increase after co-culture with not CCL3 but CXCL12 knockdown HK-2-TGF-β(1) (0.1). The expression of epithelial cell junction markers (E-cadherin and occludin) further decreased and that of mesenchymal markers (vimentin and fibronectin) further increased in HK-2-TGF-β(1) (0.1) after co-culture with PBMCs for 24 hrs (HK-2-TGF-β(1) (0.1)-PBMCs). The phosphorylation of ERK 1/2 but not smad2 and smad3 increased in HK-2-TGF-β(1) (0.1)-PBMCs. The snail and slug signaling did not increase HK-2-TGF-β(1) (0.1)-PBMCs. Although the migration and invasion of HK-2 cells induced full EMT by a high dose (10.0 ng/ml) and long-term (72-96 hrs) TGF-β(1) stimulation increased, that of HK-2-TGF-β(1) (0.1)-PBMCs did not increase. These results suggested that HK-2 cells stimulated with TGF-β(1) induced conformational activation of LFA-1 on PBMCs by increased CXCL12. Then, the direct interaction of LFA-1 on PBMCs and ICAM-1 on HK-2 cells activated ERK1/2 signaling to accelerate the part of EMT of HK-2 cells induced by TGF-β(1).

A candidate gene approach to genetic prognostic factors of IgA nephropathy--a result of Polymorphism REsearch to DIstinguish genetic factors Contributing To progression of IgA Nephropathy (PREDICT-IgAN)

BACKGROUND

Renal prognosis of IgA nephropathy (IgAN) is affected by environmental and genetic factors. Other studies demonstrated that some atherosclerotic disease-related genes were significantly associated with renal prognosis.

METHODS

The Polymorphism REsearch to DIstinguish genetic factors Contributing To progression of IgAN (PREDICT-IgAN) was a multicentre retrospective observational study to investigate associations between progression of IgAN (a 50% increase of serum creatinine level and slope of eGFR) and a hundred atherosclerotic disease-related gene polymorphisms, mainly single nucleotide polymorphisms (SNPs) in 320 IgAN patients who had more than a normal range of urinary protein (> or =0.25 g/day) at diagnosis.

RESULTS

During 8.3 +/- 4.2 years of a follow-up period, 83 patients (25.9%) developed progression. In log-rank tests, glycoprotein Ia GPIa C807T and G873A and intercellular adhesion molecule-1 ICAM-1 A1548G (K469E) were found to be significantly associated with progression even after adjustment for multiple comparisons by the method of Bonferroni (adjusted P = 0.0174, 0.0176 and 0.0430, respectively). In a multivariate Cox proportional-hazards model, GPIa 807TT (873CC) [versus 807TT, adjusted hazard ratio 2.05 (95% confidence interval 1.13-3.71)] and ICAM-1 1548GG [versus 1548AA, 2.55 (1.40-4.65)] were identified as independent genetic predictors of progression, along with conventional clinical prognostic factors such as eGFR, urinary protein and use of antihypertensives at diagnosis.

CONCLUSIONS

PREDICT-IgAN distinguished GPIa C807T/ G873A and ICAM-1 A1548G from multiple athero- sclerotic disease-related gene polymorphisms by their predictive indicator for progression of IgAN.

Glomerular expression of alpha-smooth muscle actin reflects disease activity of IgA nephropathy

To elucidate the relationship between histological disease states and clinicopathological features in immunoglobulin A nephropathy (IgAN), 90 needle-biopsy specimens diagnosed as IgAN were analyzed. The specimens were divided into four groups according to histological grade and stage index. Immunohistochemical features of alpha-smooth muscle actin (alpha-SMA), macrophages positive for myeloid/histiocyte antigen (MAC387), and expression of type I, III and IV collagens were all examined. Glomerular expression scores of alpha-SMA and the degree of intraglomerular macrophage infiltration were highest in the active and non-sclerotic groups. Type I and IV collagens were significantly more abundant in the sclerotic groups than in the active groups. Type III collagen was strongly expressed in both the active and sclerotic groups. Double immunolabeling of alpha-SMA and intercellular adhesion molecule (ICAM)-1 revealed that ICAM-1 was expressed around the alpha-SMA-positive mesangial area. In multivariate analysis, the glomerular expression score of alpha-SMA was mostly correlated with histological grading in the 10 clinicopathological parameters. Type IV collagen score was mostly correlated with histological staging. These results suggest that glomerular alpha-SMA expression reflects the histological activity of IgAN. Immunohistological staining of alpha-SMA is valuable to estimate the degree of disease activity in IgAN.

[Renal expression of intercellular adhesion molecule-1 (ICAM-1) in IgA deposit mesangial nephropathy. A tubulointerstitial lesion marker]

BACKGROUND

The aim of this study was to determine the significance of the renal expression of ICAM-1 in IgA nephropathy (IgAN).

PATIENTS AND METHOD

First, we identified ICAM-1 (CD54) expression in tubular epithelial cells and interstitial leucocytes in renal biopsies from 45 patients with IgAN and 29 patients with non-glomerulonephritis nephropathy (non-GN). We then analysed the relationship between this expression and both histological and clinical data at the time of renal biopsy and after 2.4 (2) (X [SD]) years in IgAN, and 1.8 (1.5) years in non-GN.

RESULTS

In IgAN, tubular ICAM-1 positive staining was seen in 25 (55%) biopsies; it was associated with extracapillary proliferation, glomerulosclerosis involving less than 50% of glomerular area, interstitial cell infiltration and tubular atrophy. ICAM-1 positive interstitial leucocytes were 234 (307)/mm2; this expression correlated with glomerulosclerosis, tubular atrophy, interstitial fibrosis and serum creatinine (Cr) level. In patients with 50% increase in Cr level, ICAM-1 positive interstitial leucocytes were 516 (360)/mm2 as compared with 66 (87.8)/mm2 (U = 16; p < 0.005) in patients with stable Cr. In non-GN, tubular ICAM-1 expression was observed in 7 (24%) biopsies.

CONCLUSIONS

Tubular and Interstitial expression of ICAM-1 can be a marker of tubulointerstitial damage in IgAN. Interstitial ICAM-1, rather than tubular ICAM-1, may predict the progression of this disease.

Urinary levels of interleukin-8 (IL-8) and disease activity in patients with IgA nephropathy

Using quantitative sandwich ELISA, we studied 27 patients with IgA nephropathy to determine whether the levels of urinary IL-8 might reflect the disease activity. The levels of urinary IL-8 in patients with advanced stage IgA nephropathy were significantly higher than those in the patients with the mild stage of this disease, or in the healthy controls. The results showed a positive significant correlation between the levels of IL-8 and disease activity, i.e., between levels of urinary protein and urinary casts. A significant correlation between levels of urinary IL-8 and tubular function damage was also found. It was thus suggested that measurement of urinary IL-8 might be useful in evaluating the degree of renal injuries and/or prognosis in patients with IgA nephropathy.

Urinary levels of monocyte chemoattractant protein (MCP)-1 and disease activity in patients with IgA nephropathy

Using a quantitative sandwich ELISA, we studied 17 patients with IgA nephropathy to determine if levels of urinary monocyte chemoattractant protein-1 (MCP-1) might reflect the disease activity. The levels of urinary MCP-1 in patients with the advanced stage were significantly higher than those in patients with the mild stage of the disease, or in healthy controls. The results showed a significant correlation between the levels of urinary MCP-1 and the disease activity, i.e., levels of urinary casts and urinary protein. It was thus suggested that the measurement of urinary MCP-1 is useful in evaluating the degree of renal injuries and/or prognosis in patients with IgA nephropathy.

Intercellular adhesion molecule-1 (ICAM-1), leucocyte function-associated antigen-1 (LFA-1) and leucocyte infiltration in proliferative human glomerulonephritis

The expression of the intercellular adhesion molecule-1 (ICAM-1), infiltrating cells positive for its ligand leucocyte adhesion molecule-1(LFA-1), and the markers of total leucocytes (CD45RB), T cells (CD45RO), and monocytes/macrophages (CD68) were examined by an indirect immunoperoxidase method on renal biopsy specimens from 20 patients with mesangial proliferative glomerulonephritis-IgA negative (MesProGN) and 20 with IgA nephropathy (IgAN). Histologically, normal portions of the kidney tissue (n = 15) obtained from patients with renal trauma or renal tumours were used as controls. The expression of ICAM-1 was evident and extended in mesangium, on endothelial cells of peritubular capillaries, interstitial cells, several infiltrating immune cells and on tubular epithelial cells, particularly on atrophic tubuli in renal biopsies of MesProGN and IgAN. In both types of glomerulopathies a significant increase in the number of glomerular and interstitial LFA-1-positive cells correlated positively with the expression of ICAM-1. The number of glomerular and interstitial LFA-1-positive cells correlated positively with the number of monocytes/macrophages in glomeruli and interstitium. The strong correlation between expression of ICAM-1 and LFA-1 and between LFA-1-positive cells and immune cells makes these adhesion molecules useful markers of activity and suggest that they are involved in recruitment of leucocytes in the studied types of proliferative glomerulopathies.

Glomerulointerstitial interaction of adhesion molecules in IgA nephropathy and membranoproliferative glomerulonephritis

The expression of two adhesion molecules, ICAM1 (CD54) and ICAM3 (CD50), infiltrating cells positive for their ligand, LFA1 (CD11a), and the markers of total leukocytes (CD45), T cells (CD3), granulocytes/monocytes (CD15), and macrophages (CD68) in renal interstitium were examined by an indirect immunoperoxidase method. The study was longitudinally performed on repeat renal biopsy specimens from 69 patients with two different proliferative glomerulonephritides: 43 with IgA nephropathy (IgAN) and 26 with membranoproliferative glomerulonephritis (MPGN). Interstitial ICAM1 (iICAM1) was mainly expressed on endothelium of peritubular venules and sometimes on tubular epithelium, and interstitial ICAM3 (iICAM3) on infiltrating immune cells. In IgAN, iICAM1 was significantly correlated with glomerular infiltration of LFA1+ cells (gLFA1) and CD68+ cells (gCD68) (r = 0.478/0.500; P < 0.0001) as well as CD3+ cells (gCD3) (r = 0.402; P < 0.002). In MPGN, iICAM1 was significantly correlated only with gCD68 (r = 0.382; P < 0.05). In both diseases, iICAM1 and iICAM3 were significantly correlated with interstitial infiltration of LFA1+ cells (iLFA1) and CD68+ cells (iCD68) (r = 0.616 to 0.815; P < 0.0001) and with interstitial infiltration of CD3+ cells (iCD3) (r = 0.474 to 0.816; P < 0.01). The iICAM3 was also significantly correlated with interstitial CD45+ cells (iCD45) (r = 0.672 in IgAN and 0.769 in MPGN; P < 0.00001). Interstitial infiltration of these immune cells was significantly correlated with the histologic parameters indicating renal injury, such as the index of glomerular lesion and the percent interstitial volume (r = 0.410 to 692; P < 0.05). Longitudinal analysis revealed that the parameters described above showed corresponding change with each other at the follow-up biopsy. These findings suggest that the glomeruler infiltration of T cells and macrophages influences the ICAM1/ICAM3 expression of the interstitial cells, especially In IgAN, and that ICAM1/LFA1 and ICAM3/LFA1 interactions contribute to the persistent infiltration of the interstitium by immune cells in both diseases.

Intercellular adhesion molecule-1, intercellular adhesion molecule-3, and leukocyte integrins in leukocyte accumulation in membranoproliferative glomerulonephritis type I

Marked intraglomerular infiltration of leukocytes is observed in membranoproliferative glomerulonephritis (MPGN). We recently demonstrated that this leukocyte infiltration develops partly through macrophage-1 (Mac-1)-positive cells and glomerular C3c deposits (Clin Exp Immunol 100:269-276, 1995). To further investigate the mediation of adhesion molecules in the leukocyte accumulation, we immunohistochemically examined the expression of intraglomerular leukocyte integrins and their ligands as well as surface markers for granulocytes/monocytes (CD15) and macrophages (CD68) in 26 patients with MPGN type I who had undergone repeated biopsies. These patients were divided into two groups. Group A included the patients who showed both normo-complementemia and urinary protein excretion less than 1 g/d at the follow-up biopsy (recovery group: n = 14). Group B (persistent group: n = 12) included the patients other than those in group A. At the initial biopsy, there was no difference in the degree of glomerular C3c deposition, glomerular intercellular adhesion molecule (ICAM)-1 expression, or the numbers of cells bearing leukocyte function-associated antigen-1 (LFA-1), Mac-1, and ICAM-3 between the two groups. At the follow-up biopsy, the degree of glomerular C3c deposition, and the numbers of cells bearing LFA-1, Mac-1, and ICAM-3, were significantly decreased only in group A (P < 0.01, P < 0.001, P < 0.001, and P < 0.01, respectively). No chronological change in ICAM-1 expression was observed in either group. Group B showed a chronological increase in the severity of glomerular injury and serum creatinine level, associated with persistent heavy proteinuria. Neither LFA-1- nor Mac-1-positive cells were positively correlated with ICAM-1 expression. Most of Mac-1-positive cells were CD15-positive cells (granulocytes/monocytes), and a considerable number of Mac-1-positive cells concurrently expressed ICAM-3. In contrast, most LFA-1-positive cells were considered to be CD68-positive cells (macrophages). The number of cells bearing LFA-1 was positively correlated with that of cells bearing ICAM-3 (P < 0.00001). These results suggest that the glomerular leukocytes, infiltrating through Mac-1/complement interaction, express ICAM-3 by themselves, and that LFA-1/ICAM-3 interaction might participate in the glomerular aggregation of leukocytes in MPGN type I. In this study, we could not conclude that LFA-1/ICAM-1 or Mac-1/ICAM-1 interaction was involved in the leukocyte accumulation in this disease.

Intercellular adhesion molecule-1/leukocyte function associated antigen-1-mediated and complement receptor type 4-mediated infiltration and activation of glomerular immune cells in immunoglobulin A nephropathy

Glomerular expression of intercellular adhesion molecule-1 (ICAM1) (CD54) and membrane cofactor protein (MCP; CD46) and positive infiltrating cells in leukocyte function associated antigen-1 (LFA1)alpha (CD11a) and C3bi receptors (CR3/CD11b, CR4/CD11c) were examined by the indirect immunoperoxidase method on 43 sets of repeated renal biopsy specimens from patients with immunoglobulin A nephropathy. Twenty-four-hour urine protein at the time of renal biopsy was also evaluated. Glomerular infiltration of LFA1alpha+ cells was significantly correlated with glomerular expression of ICAM1 (r = 0.494, P < 0.0001). Glomerular complement receptor type 4 (CR4)+ cells were significantly correlated with glomerular expression of MCP (r = 0.405, P < 0.0001). The glomerular expressions of ICAM1 and MCP were significantly correlated with each other (r = 0.700, P < 0.00001). The glomerular infiltrations of LFA1alpha+ and CR4+ cells were highly correlated with each other (r = 0.884, P < 0.00001), and both cell types were significantly correlated with urine protein (respectively, r = 0.426 and 0.478, P < 0.001 and 0.0001). When the change in these parameters between the time of the initial and follow-up biopsies was evaluated, there was a significant correlation between the change in glomerular expression of ICAM1 (DeltaICAM1) and MCP (DeltaMCP) as well as between the change in glomerular infiltration of LFA1alpha+ cells (DeltaLFA1alpha+) and CR4+ cells (DeltaCR4+). Both DeltaLFA1alpha+ and DeltaCR4+ were significantly correlated with the change in urine protein. These findings suggest that ICAM1/LFA1 interaction and MCP-mediated C3bi/C3biR interaction cooperate and participate in persistent glomerular infiltration of immune cells in immunoglobulin A nephropathy, and that these LFA1alpha+ and C3biR+ cells contribute to the induction of proteinuria.