Biological control of the grapevine diseases ‘grey mold’ and ‘powdery mildew’ by Bacillus B27 and B29 strains.

Uncinula necator and Botrytis cinerea are the most destructive pathogens of the grapevine in Tunisia and elsewhere. We used two strains of Bacillus subtilis group, B27 and B29 to control powdery mildew and the grey mold disease of the grapevine. Green house experiments showed that B29 and B27 strains of the bacteria efficiently reduced the severity of powdery mildew up to 50% and 60%, respectively. Further, they decreased Botrytis cinerea development on grape leaf by 77% and 99%, respectively. The mode of action has been shown to be chitinolytic. These two bacteria showed significant production of total proteins discharged into the culture medium. Determination of some chitinolytic enzymes revealed the involvement of N-acetyl glucosaminidase (Nagase), the chitin-1,4-chitobiosidase (Biase) and endochitinase in degrading the mycelium of B. cinerea.

S1000A12, Chitotriosidase, and Resolvin D1 as Potential Biomarkers of Familial Mediterranean Fever

Familial Mediterranean fever (FMF) is an auto-inflammatory disease characterised by periodic inflammatory attacks. We investigated changes in monocyte-granulocyte derived S10012A and chitotriosidase in both the attack and silent period of FMF for better estimation of inflammation. Endogenous resolvin was determined for utility to restrict inflammation. This study included 29 FMF patients (15 M/14 F) and 30 healthy controls (15 M/15 F). Serum levels of highly sensitive C-reactive protein, serum amiloid A (SAA), S100A12, chitotriosidase, and resolvin D1 were measured. Age, sex, body mass indexes, and lipids were similar between patients and controls. Biomarkers including hs-CRP, SAA, S100A12, chitotriosidase, and resolvin D1 were higher in the attack period of FMF patients compared to controls (P < 0.001). When FMF patients in the silent period were compared with their attack period, hs-CRP, SAA, and chitotriosidase were found elevated in the attack period (P < 0.001, P < 0.001, and P = 0.02 respectively). Serum levels of SAA, S100A12, chitotriosidase, and resolvin D1 in the silent period of FMF patients were still found elevated compared to healthy controls, indicating subclinical inflammation (P < 0.001, P < 0.001, P = 0.009, and P < 0.001 respectively ). In subgroup analysis, patients with M694V homozygote and heterozygote mutations had higher S10012A and hs-CRP compared to other mutation carriers. Our findings indicate that chitotriosidase and S10012A are useful in diagnosis and detection of subclinical inflammation and/or assessment of disease activity in FMF patients. They could be more informative for inflammation in various disease states compared to hsCRP and SAA. Resolvin D1 is elevated in both the attack and silent periods of FMF. It may be helpful to restrict inflammation.

Streptozotocin-induced diabetes mellitus affects lysosomal enzymes in rat liver

It has been previously shown that dextran sulfate administered to diabetic rats accumulates in the liver and kidney, and this could be due to a malfunction of the lysosomal digestive pathway. The aim of the present study was to evaluate the expression and activities of lysosomal enzymes that act upon proteins and sulfated polysaccharides in the livers of diabetic rats. Diabetes mellitus was induced by streptozotocin in 26 male Wistar rats (12 weeks old), while 26 age-matched controls received only vehicle. The livers were removed on either the 10th or the 30th day of the disease, weighed, and used to evaluate the activity, expression, and localization of lysosomal enzymes. A 50-60% decrease in the specific activities of cysteine proteases, especially cathepsin B, was observed in streptozotocin-induced diabetes mellitus. Expression (mRNA) of cathepsins B and L was also decreased on the 10th, but not on the 30th day. Sulfatase decreased 30% on the 30th day, while glycosidases did not vary (or presented a transitory and slight decrease). There were no apparent changes in liver morphology, and immunohistochemistry revealed the presence of cathepsin B in hepatocyte granules. The decrease in sulfatase could be responsible for the dextran sulfate build-up in the diabetic liver, since the action of sulfatase precedes glycosidases in the digestive pathway of sulfated polysaccharides. Our findings suggest that the decreased activities of cathepsins resulted from decreased expression of their genes, and not from general lysosomal failure, because the levels of glycosidases were normal in the diabetic liver.

Modifiers of TGF-beta1 effector function as novel therapeutic targets of pulmonary fibrosis

Pulmonary fibrosis is a fatal progressive disease with no effective therapy. Transforming growth factor (TGF)-beta1 has long been regarded as a central mediator of tissue fibrosis that involves multiple organs including skin, liver, kidney, and lung. Thus, TGF-beta1 and its signaling pathways have been attractive therapeutic targets for the development of antifibrotic drugs. However, the essential biological functions of TGF-beta1 in maintaining normal immune and cellular homeostasis significantly limit the effectiveness of TGF-beta1-directed therapeutic approaches. Thus, targeting downstream mediators or signaling molecules of TGF-beta1 could be an alternative approach that selectively inhibits TGF-beta1-stimulated fibrotic tissue response while preserving major physiological function of TGF-beta1. Recent studies from our laboratory revealed that TGF-beta1 crosstalk with epidermal growth factor receptor (EGFR) signaling by induction of amphiregulin, a ligand of EGFR, plays a critical role in the development or progression of pulmonary fibrosis. In addition, chitotriosidase, a true chitinase in humans, has been identified to have modulating capacity of TGF-beta1 signaling as a new biomarker and therapeutic target of scleroderma-associated pulmonary fibrosis. These newly identified modifiers of TGF-beta1 effector function significantly enhance the effectiveness and flexibility in targeting pulmonary fibrosis in which TGF-beta1 plays a significant role.

Pathophysiology of liver diseases: impact of tumor necrosis factor alpha receptor 1 and hexosaminidase

Liver disease is the main cause of morbidity and mortality worldwide. The spectrum of the disease ranged from fatty liver to hepatic inflammation; necrosis, progressive fibrosis and hepatocellular carcinoma. We evaluated the serum levels of soluble tumor necrosis factor-alpha receptor 1, total B-hexosaminidase and its isoenzymes Hex A and B activities and nitric oxide in patients with liver diseases and their association with aminotransferase level. Seventy patients and 12 healthy subjects were recruited. Patients were divided into 3 groups; chronic hepatitis group [20 patients], liver cirrhosis group [30 patients] and malignant liver group [20 patients]. Serum levels of soluble tumor necrosis factor-alpha receptor 1, total B-hexosaminidase and its isoenzymes Hex A and B activities and nitric oxide were measured. Serum levels of soluble tumor necrosis factor-alpha receptor 1, total B-hexosaminidase activity and nitric oxide were significantly higher in the liver disease patients. Serum levels of isoenzvmes Hex A and B were significantly higher in malignant liver patients. Total Bhexosaminidase and its isoenzyme Hex A activity levels were significantly higher in +ve HBsAg and +ve Anti-HCV patients. Serum levels of soluble tumor necrosis factor-alpha receptor 1 were positively correlated with aminotransferase level. Taken together, these findings suggested that these biochemical indices might reflect ongoing disease activity and played an important role in the pathophysiology of liver diseases

Clinical and genetic characteristics of Gaucher disease according to phenotypic subgroups / 소아과

PURPOSE: Gaucher disease is caused by a beta-glucocerebrosidase (GBA) deficiency. The aim of this study is to investigate the clinical and genetic characteristics according to subtypes of Gaucher disease in the Korean population. METHODS: Clinical findings at diagnosis, GBA mutations, and clinical courses were reviewed in 20 patients diagnosed with Gaucher disease. RESULTS: Eleven patients were diagnosed with non-neuronopathic type, 2 with acute neuronopathic type, and 7 with chronic neuronopathic type. Most patients presented with hepatosplenomegaly, thrombocytopenia, and short stature. In the neuronopathic group, variable neurological features, such as seizure, tremor, gaze palsy, and hypotonia, were noted at age 8.7+/-4.3 years. B cell lymphoma, protein-losing enteropathy, and hydrops fetalis were the atypical manifestations. Biomarkers, including chitotriosidase, acid phosphatase, and angiotensin-converting enzyme, increased at the initial evaluation and subsequently decreased with enzyme replacement treatment (ERT). The clinical findings, including hepatosplenomegaly, thrombocytopenia, and skeletal findings, improved following ERT, except for the neurological manifestations. L444P was the most common mutation in our cohort. One novel mutation, R277C, was found. CONCLUSION: Although the clinical outcome for Gaucher disease improved remarkably following ERT, the outcome differed according to subtype. Considering the high proportion of the neuronopathic form in the Korean population, new therapeutic strategies targeting the central nervous system are needed, with the development of a new scoring system and biomarkers representing clinical courses in a more comprehensive manner.

Clinical and genetic characteristics of Gaucher disease according to phenotypic subgroups / 소아과

PURPOSE: Gaucher disease is caused by a beta-glucocerebrosidase (GBA) deficiency. The aim of this study is to investigate the clinical and genetic characteristics according to subtypes of Gaucher disease in the Korean population. METHODS: Clinical findings at diagnosis, GBA mutations, and clinical courses were reviewed in 20 patients diagnosed with Gaucher disease. RESULTS: Eleven patients were diagnosed with non-neuronopathic type, 2 with acute neuronopathic type, and 7 with chronic neuronopathic type. Most patients presented with hepatosplenomegaly, thrombocytopenia, and short stature. In the neuronopathic group, variable neurological features, such as seizure, tremor, gaze palsy, and hypotonia, were noted at age 8.7+/-4.3 years. B cell lymphoma, protein-losing enteropathy, and hydrops fetalis were the atypical manifestations. Biomarkers, including chitotriosidase, acid phosphatase, and angiotensin-converting enzyme, increased at the initial evaluation and subsequently decreased with enzyme replacement treatment (ERT). The clinical findings, including hepatosplenomegaly, thrombocytopenia, and skeletal findings, improved following ERT, except for the neurological manifestations. L444P was the most common mutation in our cohort. One novel mutation, R277C, was found. CONCLUSION: Although the clinical outcome for Gaucher disease improved remarkably following ERT, the outcome differed according to subtype. Considering the high proportion of the neuronopathic form in the Korean population, new therapeutic strategies targeting the central nervous system are needed, with the development of a new scoring system and biomarkers representing clinical courses in a more comprehensive manner.

Correlation between glomerular filtration rate and urinary N acetyl-beta-D glucosaminidase in children with persistent proteinuria in chronic glomerular disease / 소아과

PURPOSE: Urinary excretion of N acetyl-beta-D glucosaminidase (NAG) and beta2-microglobulin (beta2-M) was increased in the presence of proximal tubular damage. Based on these urinary materials, we investigated the ability of expecting renal function in chronic glomerular diseases. In this study, we evaluated the relationship between glomerular filtration rate (GFR) urinary NAG, and urinary beta2-M. METHODS: We evaluated 52 children with chronic kidney disease at the Chung-Ang University Hospital between January 2003 and August 2009. We investigated the 24-hour urinalysis and hematologic values in all 52 patients. Serum creatinine, creatinine clearance (Ccr), serum cystatin C, urinary beta2-M and urinary NAG were measured. RESULTS: Out of 52 patients, there were 13 children with minimal change in disease, 3 children with focal segmental glomerulosclerosis, 17 children with immunoglobulin A nephropathy, 15 children with Henoch-Schonlein purpua nephritis, 3 children with poststreptococcal glomerulonephritis, and 1 child with thin glomerular basement membrane disease. In these patients, there were significant correlation between the Ccr and urinary NAG (r=-0.817; P<0.01), and between the GFR (as determined by Schwartz method) and urinary NAG (r=-0.821; P<0.01). In addition, there was a significant correlation between the GFR (as determined by Bokencamp method) and urinary NAG (r=-0.858; P<0.01). CONCLUSION: In our study, there was a significant correlation between the GFR and urinary NAG, but there was no correlation between the GFR and urinary beta2-M, suggesting that the GFR can be predicted by urinary NAG in patients with chronic glomerular disease.

Comparison and clinical application of two methods for determination of plasma chitotriosidase activity / 中华儿科杂志

<p><b>OBJECTIVE</b>Chitotriosidase (CT) is a plasma biomarker for Gaucher disease (GD), the enzyme activity is usually markedly elevated in plasma of Gaucher patients, and it was reported that levels of plasma chitotriosidase activity was mildly-moderately increased in patients with Niemann-Pick disease (NPD). The aim of this study was to compare chitotriosidase activity using 4-methylumbelliferyl-β-D-N, N', N″-triacetyl-chitotrioside (4MU-C3) with 4-methylumbelliferyl 4-deoxy-β-D-chitobiose (4MU-4dC2) as substrates, and apply chitotriosidase activity measurement to help clinical determination of GD and NPD, and to monitor therapy in GD patients.</p><p><b>METHOD</b>Plasma of 45 healthy individuals, 31 patients with GD and 9 patients with NPD type A/B was collected from outpatient clinics of the Department of Pediatric Endocrinologic, Genetic and Metabolic Diseases, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine. Plasma chitotriosidase activity was measured with the substrates 4MU-C3 and 4MU-4dC2 respectively. Determinations were based on the methods described by Hollak et al and Rodrigues et al. Meanwhile, common mutation dup24 of the human chitotriosidase gene was detected.</p><p><b>RESULT</b>(1) Chitotriosidase activity when measured with 4MU-4dC2 gave higher values than 4MU-C3. In the healthy controls chitotriosidase activity was increased 3.7-fold when the 4MU-dC2 was used as substrate as compared with the 4MU-C3 (Z = -4.703, P < 0.001). In the untreated GD patients, the median value was increased 794-fold and 610-fold of the control subjects (Z = -3.823, P < 0.001) when the enzyme was measured with two substrates respectively. In the GD patients during therapy, chitotriosidase activity was increased 134-fold and 79-fold, and after changing therapeutic dose chitotriosidase activity was increased 215-fold and 118-fold of the controls (Z = -2.521, P < 0.05). In the NPD patients chitotriosidase activity was increased 8-fold and 14-fold of the controls (Z = -1.604, P = 0.109). (2) Consistent with the results of chitotriosidase activity, 30 of 85 (35.3%) individuals were homozygotes of dup24 mutation, which are completely chitotriosidase enzyme deficiency. Among GD patients with wild-type and heterozygotes for the dup24 mutation, chitotriosidase activity highly increased in the plasma compared with the controls.</p><p><b>CONCLUSION</b>The use of 4MU-4dC2 as substrate makes chitotriosidase activity measurement more sensitive. The determination of plasma chitotriosidase activity is a useful tool to assist the clinical identification of Gaucher disease, and to monitor enzyme replacement therapy (ERT) of non-chitotriosidase deficient GD patients. Chitotriosidase activity determination has no value in the clinical identification of NPD.</p>

The mechanism of the anticancer function of M1 macrophages and their use in the clinic / 癌症

M1-type macrophages are capable of inducing lysis in various types of cancer cells, but the mechanism of action is unclear. It has been noted that an "unknown protein" produced together with protease by activated macrophages is responsible for this action. Activated M1 macrophages have been recently reported to produce family 18 chitinases, all of which have been named chitotriosidase. Our experiments have demonstrated that family 18 chitinases work together with proteases and can damage various cancer cells both in vitro and in vivo. Thus, in this article, we suggest that the 50-kDa chitotriosidase is the reported "unknown protein". In addition, we discuss how to properly stimulate activated M1 macrophages to produce 50-kDa chitotriosidases and proteases for destroying cancer cells. Because family 19 chitinase has recently been reported to kill cancer cells, we also discuss the possibility of directly using human family 18 chitotriosidase and the humanized plant family 19 chitinase for cancer treatment.

Serum Chitotriosidase Activity in Pulmonary Tuberculosis: Response to Treatment and Correlations with Clinical Parameters

BACKGROUND: Chitotriosidase is an accepted marker of macrophage activation. In this study, we investigated serum chitotriosidase levels in pulmonary tuberculosis (PTB). METHODS: Forth-two patients with PTB and 30 healthy subjects were enrolled in the study. The radiological extent of PTB, radiological sequela after treatment, and the degree of smear positivity were assessed. Chitotriosidase levels were measured by a fluorometric method. RESULTS: The serum chitotriosidase levels of the PTB patients were significantly higher than those of the control subjects (39.73+/-24.97 vs. 9.63+/-4.55 nmol/mL/h, P<0.001). After completion of the standard 6-month antituberculous treatment, chitotriosidase levels in PTB patients significantly decreased (10.47+/-4.54 nmol/mL/h, P<0.001). Chitotriosidase levels correlated significantly with the radiological extent of PTB, degree of smear positivity, and post-treatment radiological sequela score (r=0.439, r=0.449, and r=0.337, respectively). CONCLUSIONS: This study demonstrated that serum chitotriosidase levels increase in PTB; therefore, chitotriosidase can be used as a marker of disease activity, severity, and response to treatment.

Association of Blood and Bone Lead with a Decrease in Renal Function Indices in Patients with Chronic Kidney Disease / 대한신장학회지

PURPOSE: This study assessed the environmental lead exposure in patients with chronic kidney disease (CKD) and the relationship between lead exposure and renal function indices. METHODS: Seventy-one patients with CKD and 40 control subjects without known renal disease were included. Blood lead was measured by atomic absorption spectrophotometry and tibial lead was measured via 109Cd-based K-shell X-ray fluorescence. Blood urea nitrogen (BUN), serum creatinine, urine creatinine and urine N-acetyl-beta glucosaminidase (NAG) were also measured. Blood lead was corrected with hematocrit (female: 35%, male: 42%) to adjust for differences in anemic status of patients compared with control subjects. RESULTS: The mean level of hematocrit-adjusted blood lead was significantly higher in patients with CKD (4.18+/-1.74 microg/dL) compared with that in control subjects (3.00+/-0.92 microg/dL); the mean tibial lead level tended to be higher in patients with CKD (3.38+/-9.93 microg/g) than that in control subjects (1.28+/-7.92 microg/g), but no statistical significance was observed. In a multivariate regression analysis after adjusting for gender, age, and drinking and smoking status, adjusted blood lead was a significant predictor of increases in BUN and serum creatinine, but not of the level of urine NAG or creatinine. In contrast, no significant association between tibial lead and renal indices was observed in the multivariate regression analysis. CONCLUSION: These results suggest that environmental lead exposure may compromise renal function.

Effect of Qingkailing injection (QKLI) on complement and RBL-2 H3 cells in virto / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the effect of Qingkailing injection (QKLI) on complement and RBL-2 H3 cells in virto.</p><p><b>METHOD</b>The mixture of human serums and QKLI were incubated for 30 min in vitro and then the content of SC5 b-9 in the mixture was determined by ELISA. RBL-2 H3 cells were cultured and treated by QKLI. Beta-heosaminidase release rate was measured by coloration method. The content of histamine in supernatant was tested by ELISA.</p><p><b>RESULT</b>The QKLI can reduce the content of SC5 b-9 (P<0.05) and promote the release of beta-heosaminidase and histamine significantly (P<0.05).</p><p><b>CONCLUSION</b>QKLI didn't induce the complement activation, but induced the release of beta-heosaminidase and histamine directly. Therefore, the clinical adverse reactions of QKLI in clinic may be pseudoallergy which had no relation with the activation of complement system.</p>

Plasma chitotriosidase activity in children with lysosomal storage disorders.

Chitotriosidase (ChT) is an enzyme that is selectively activated in tissue macrophage. This property of ChT makes it a potential marker for many disease process and prognostication. Present study has been carried out to know the significance of ChT as a screening marker in lysosomal storage disorders (LSDs) where tissue macrophage activation is commonly observed due to accumulation of substrate in various organs of the body. Study comprises of 20 healthy children in the age range of 10 days to 5 yrs and 56 children in the age range of 2.5 months to 13 yrs with regression of milestones, skeletal dysplasia, neuroregression and hepatosplenomegaly were selected for plasma ChT who had confirmed LSDs as carried out by specific lysosomal enzyme study from the leukocytes or fibroblasts. Plasma ChT was 55.21 ± 20.81 nmol/ml /hr in twenty healthy age matched controls. Plamsa ChT level was 42.88 to 79.78 nmol/ml/hr in thirteen of 56 (23.21%) children with LSDs like Morquio- B, Pompe, Metachromatic leucodystrophy (MLD), Sandhoff and Niemann-Pick disease type C (NPD-C). While in 43 (76.78%) children it was in the range of 213.74 to 23,511.40 nmol/ml/hr. who had LSDs like Morquio-B, Sly syndrome, MLD, GM2 Gangliosidosis, NPD-A/B and Gaucher disease (GD). Marked elevated ChT (4,000 to 23,511 nmol/ml/hr) was observed in all cases of GD (n=7) and NDP-A/B. It can be concluded from the present study that moderately raised activity of ChT can be utilized as a positive predictive test for certain LSD’s. Those with marked elevated ChT have confirmed GD or NPD-A/B making it a strong screening marker for this group of diseases.

An Anesthetic Experience in a Patient with Tay-Sachs Disease : A case report / 대한마취과학회지

Tay-Sachs Disease (TSD), the most common form of GM(2) gangliosidosis, is an autosomal recessive inborn lysosomal glycosphingolipid storage disease which is resulted from the mutations that affect the alpha-subunit locus on chromosome 15 and cause a severe deficiency of hexosaminidase A. It is characterized by normal motor development in the first few months of life, followed by progressive weakness and loss of motor skills beginning around 6 months of life. Neurodegeneration is relentless and manifested as relentless motor and mental deterioration, beginning with motor incoordination, mental obtundation leading to muscular flaccidity, blindness, and increasing dementia, with death occurring by the age of 4 or 5 years. We report a successful anesthetic management in a patient with Tay-Sachs Diseases for tracheostomy and feeding gastrostomy.

Urinary tubular enzyme excretion in children with nephrolithiasis and urolithiasis with hydronephrosis

Objective: Nephrolithiasis and urolithiasis are recurrent conditions associated with significant morbidity and economilc impact. Previous studies have suggested that cell- crystal interactions lead to tubular damage and/or dysfunction. To find further proof for these observations, a metabolic evaluation [including serum and urine biochemistry and urinary enzyme excretion] was done in children with nephrolithiasis and urolithiasis with hydronephrosis

Patients and Methods: This study included two groups: 10 normal children [controls] and 32 children with calcium oxalate urinary tract stones. The latter group was further subdivided into those with nephrolithiasis [n=12] and urolithiasis with hydronephrosis [n=20]. Levels of uric acid, oxalate, calcium, magnesium and inorganic phosphorus in 24-hour urine and serum were determined. Urinary N-acetyl-beta-D-glucosaminidase [NAG], beta-galactosidase [beta-GAL], beta-hexosaminidase [beta-Hex], angiotensin converting enzyme [ACE] and gamma glutamyl transferase [y-GT] levels were also determined colorimetrically

Results: Increases in urinary excretion of oxalate, calcium, magnesium and inorganic phosphorus were the major abnormalities found in stone forming patients. Elevated urinary NAG, beta-GAL, beta-Hex and ACE levels were also noted in patients compared with controls. Urinary excretion of oxalate, NAG, beta-GAL and ACE was significantly elevated in children with nephrolithiasis compared to those with urolithiasis and hydronephrosis

Conclusion: Abnormal urine biochemistry seems to have a role in the risk for urinary-tract stone formation in children. Hyperoxaluria can induce tubular cell injury mainly in proximal tubules, which is more pronounced in children with nephrolithiasis. The tubular injury manifested by enzymuria occurs before alteration of renal functions and blood biochemistry. Urinary tubular enzymes should be screened in children with urinary tract stones

Functions of Siglecs in Allergic Inflammation / 소아알레르기및호흡기학회지

Siglecs are sialic acid binding Ig-like lectins, subset of the immunoglobulin superfamily. They are characterized by a homologous N-terminal V-set Ig-like domain and C2 set Ig-like domains. N-terminal domains have sialic acid binding activity. In humans, 11 Siglecs have been described sialoadhesin(Siglec-1), CD22(Siglec-2), CD33(Siglec-3), MAG(Siglec-4), more recently described CD33-related Siglecs(Siglec 5-11). Siglecs express most signal via immunoreceptor tyrosine-based inhibition motif(ITIM) cytoplasmic domains. The cytoplasmic tails of all Siglecs except sialoadhesin have one or more tyrosine residues within potential signaling motifs. Inhibitory function of other Siglecs such as Siglec-7 or Siglec-9 was shown in RBL-2H3 cells. Co-crosslinking of Siglec-7 or Siglec-9 and Fc epsilon R1 substantially reduced the serotonin release of RBL-7 and RBL-9 cells. Siglec-8 is expressed on human eosinophils, mast cells and basophils. Siglec-8 has two tyrosine motifs, a proximal motif and a distal motif. They have some inhibitory functions in immune system. We have observed that Siglec-8 is able to inhibit the IgE receptor-mediated beta-hexosaminidase release of RBL-2H3 cells following co-crosslinking. Co-crosslinking of Siglec-8 and Fc epsilon R1 reduced the hexosaminidase release of RBL-2H3 cells. These results show that Siglec-8 is as potent as Siglec-7 and Siglec-9 in delivering inhibitory signals to RBL-2H3 cells. Siglec-8 should be a new member of the inhibitory receptor superfamily and the membrane-proximal ITIM is essential for the inhibitory function of Siglec-8 molecules. Although these molecules present specific marker for the allergic cell types, more work is needed to understand the signaling mechanism and the role in various disease processes.

Role of Urinary N-acetyl-beta-D- glucosaminidase Level in Prediction of Pathological Tubular Lesion and Prognosis in Subclinical Asymptomatic IgA Nephropathy / 대한신장학회잡지

PURPOSE: Urinary N-acetyl-beta-D-glucosaminidase (NAG) has been known to reflect the damage of proximal tubular cells in the early stages of renal disease. Recent studies have demonstrated that tubular grade predicted renal outcome better than did other histological parameters in IgA nephropathy. We evaluated the meaning of urinary NAG in relation with initial histological features and renal outcomes in early subclinical IgA nephropathy. METHODS: Among the firstly diagnosed IgA nephropathy patients from Jan 2001 to Dec 2002, 43 subjects were selected with the criteria of normal renal function and 24-h urinary protein excretion <3.5 g/day. The subjects were followed for 2 years. Pathologic lesion was graded according to HASS classification and semiquantitative scorings, from 0 to 3, were carried out for glomerular (GG), interstitial (IG), tubular (TG), and vascular (VG) lesion. RESULTS: The subjects consisted of 20 male and 23 female with mean age of 30+/-13 years, baseline blood pressure 116+/-15/74+/-10 mmHg, Cr 1.03+/-0.24 mg/dL, Ccr 88+/-19 mL/min, 24-h urinary protein excretion (UPER) 1, 790+/-1, 610 mg/24-h, urinary NAG 11.8+/-11.0 U/g cr at the time of biopsy. Hass subclass was correlated significantly with glomerular, tubular, and interstitial grades (all p<0.05). In comparison with clinical parameters, glomerular grade was significantly related with 24-h UPER (p<0.05) and tubular grade was significantly related with systolic blood pressure (p<0.05). Urinary NAG level at the time of biopsy show significant correlation with tubular grade (p<0.05). Progression of renal disease occurred in nine patients (20.9%). The patients with renal disease progression showed significantly low baseline Ccr, high 24-h UPER, and high NAG (all p<0.05). In pathological findings, tubular grade was significantly related with renal prognosis (p<0.05). In regression analysis, tubular grade was a independent predictor of renal prognosis among above four parameters showing significant differences. In survival analysis, tubular grade 0, 1 and grade 2, 3 showed significant difference in renal survival as compared to each other. The patients with baseline NAG urinary NAG above 10 U/g Cr showed significantly worse renal survival as compared with those below 10 U/g Cr (p<0.05). CONCLUSION: Tubular lesion is an independent factor associated with renal progression in these patients. Urinary NAG reflects well the degree of tubular lesion at the time of biopsy. We carefully suggest, therefore, that the measurement of urinary NAG level is helpful to estimate tubular lesion and predict renal prognosis in subclinical asymptomatic IgA nephropathy patients before they undergo renal biopsy.