Sustained Tubulointerstitial Inflammation in Kidney with Severe Leptospirosis.

Leptospirosis is frequently associated with acute kidney injury. Some survivors are known to progress to chronic kidney disease due to sustained tubulointerstitial inflammation. We present a case of severe leptospirosis with acute renal failure. Although antibiotic therapy resolved the infection, moderate renal dysfunction remained. A renal biopsy demonstrated marked inflammatory infiltration in the tubules and interstitium. Many of the inflammatory cells were CD68-positive monocytes/macrophages, predominantly M1 phenotype. An intermediate dose of oral corticosteroids normalized the patient's serum creatinine levels. We suggest that corticosteroid therapy may be a therapeutic option for some patients with sustained tubulointerstitial nephritis who survive severe leptospirosis.

The selection of peritoneal mesothelial cells is important for cell therapy to prevent peritoneal fibrosis.

Long-term peritoneal dialysis (PD) causes chronic peritoneal damage. Peritoneal mesothelial cells (PMCs) play an important role in peritoneal function. We investigated the possibility of cell therapy using the PMCs to prevent peritoneal damage in PD patients. We harvested human PMCs from the PD effluent of PD patients. The PMCs were separated based on morphological characteristics into epithelial-like (Epi) cells and fibroblast-like (Fib) cells by the limiting dilution method. We transplanted these cells into nude mice whose parietal and visceral peritoneum were scratched by mechanical scraping. The transplanted cells were detected at the parietal and visceral peritoneum. Compared with the positive control, the Epi cell therapy group showed very few adhesions and exhibited no thickening of the parietal and visceral peritoneum. However, the group with Fib cell therapy could not inhibit peritoneal adhesion and thickening. In addition, hepatocyte growth factor was expressed by the grafted Epi cells but not Fib cells. Fib cells expressed vascular endothelial growth factor stronger than Epi cells. These two types of cells from the same patient showed different characteristics and effects for cell therapy. These findings suggest that the PMCs from the PD patient showed different characteristics, such as Epi cells and Fib cells, and the selection of PMCs is important for cell therapy on the point of not only the direct cellular interactions but also cytokine secretion from the grafted cells. Furthermore, the differences in the morphological cell characteristics may influence their role in peritoneal regeneration.

Suppression of adiponectin by aberrantly glycosylated IgA1 in glomerular mesangial cells in vitro and in vivo.

The pathogenesis of IgA nephropathy (IgAN) may be associated with the mesangial deposition of aberrantly glycosylated IgA1. To identify mediators affected by aberrantly glycosylated IgA1 in cultured human mesangial cells (HMCs), we generated enzymatically modified desialylated and degalactosylated (deSial/deGal) IgA1. The state of deglycosylated IgA1 was confirmed by lectin binding to Helix aspersa (HAA) and Sambucus nigra (SNA). In the cytokine array analysis, 52 proteins were upregulated and 34 were downregulated in HMCs after stimulation with deSial/deGal IgA1. Among them, the secretion of adiponectin was suppressed in HMCs after stimulation with deSial/deGal IgA1. HMCs expressed mRNAs for adiponectin and its type 1 receptor, but not the type 2 receptor. Moreover, we revealed a downregulation of adiponectin expression in the glomeruli of renal biopsy specimens from patients with IgAN compared to those with lupus nephritis. We also demonstrated that aberrantly glycosylated IgA1 was deposited in the mesangium of patients with IgAN by dual staining of HAA and IgA. Moreover, the urinary HAA/SNA ratio of lectin binding was significantly higher in IgAN compared to other kidney diseases. Since adiponectin has anti-inflammatory effects, including the inhibition of adhesion molecules and cytokines, these data suggest that the local suppression of this adipokine by aberrantly glycosylated IgA1 could be involved in the regulation of glomerular inflammation and sclerosis in IgAN.

Abnormalities of glycogenes in tonsillar lymphocytes in IgA nephropathy.

Glycosylation, which represents the most complex post-translational modification, plays a pivotal role during protein maturation, and is orchestrated by numerous glycosyltransferases. Aberrant O-glycosylation of serum and tonsillar IgA1 is presumed to be one of the pathogeneses of IgA nephropathy (IgAN). However, the synthesis of underglycosylated IgA1 in tonsils has not yet been characterized. This study investigated tonsillar B lymphocytes of IgAN using tonsils from patients with chronic tonsillitis and sleep apnea syndrome. Gene expression of ß1,3-galactosyltransferase (ß3GalT), Cosmc, UDP-N-acetyl-α-D-galactosamine: polypeptide N-acetylgalactosaminyl-transferase 2, were significantly down regulated in tonsillar CD19-positive B lymphocytes from IgAN patients compared to control as determined by real-time RT-PCR. In contrast, the level of sialyltransferase was not significantly different among the three groups. Tonsillar B cell ß3GalT gene expression significantly correlated with estimated GFR and negatively correlated with proteinuria and glomerular or interstitial injury score. Double immunofluorescent staining showed that some IgA-positive cells in the intrafollicular area were also positive for ß3GalT staining. Western blotting showed the protein expression of ß3GalT in the tonsils to significantly decrease in IgAN in comparison to the controls. These data suggest the downregulation of ß3GalT in tonsillar B lymphocytes to be closely associated with the clinical characteristics of IgAN.

Differential expression of glycogenes in tonsillar B lymphocytes in association with proteinuria and renal dysfunction in IgA nephropathy.

Aberrant O-glycosylation of serum and tonsillar IgA1 is one of the main pathogeneses of IgA nephropathy (IgAN). However, the synthesis of underglycosylated IgA1 in tonsils has not yet been characterized. This study examined tonsillar B lymphocytes of IgAN (n=34) using tonsils derived from patients with chronic tonsillitis (n=24) and sleep apnea syndrome (n=14) as a control. Gene expression of beta1,3-galactosyltransferase (beta3GalT), and the core 1 beta3GalT-specific molecular chaperone, Cosmc, UDP-N-acetyl-alpha-D-galactosamine: polypeptide N-acetylgalactosaminyl-transferase 2, were significantly decreased in tonsillar CD19-positive B lymphocytes from IgAN patients compared to control tonsillar tissues as determined by real-time RT-PCR. Tonsillar B cell beta3GalT gene expression significantly correlated with estimated GFR and negatively correlated with proteinuria and histological injury score. Western blotting showed the protein expression of beta3GalT in the tonsils to significantly decrease in IgAN in comparison to the controls. These data suggest the downregulation of beta3GalT in tonsillar B lymphocytes to be closely associated with the clinical characteristics of IgAN.