The role of tumor necrosis factor-alpha in Henoch-Schonlein purpura

The Immunologic Profiles of Kawasaki Disease Triggered by Mycoplasma pneumoniae Infection

OBJECTIVE

We compared the immunologic characteristics of mycoplasma pneumoniae-triggered Kawasaki disease (MP-KD) with Kawasaki disease (KD) not associated with mycoplasma pneumoniae (MP), with mycoplasma pneumoniae-triggered Henoch-Schönlein purpura (MP-HSP), and with healthy controls.

METHODS

Complement levels, cellular and humoral immunity were assessed in KD, in MP-KD, in MP-HSP, and in healthy children.

RESULTS

Of 622 children with KD, 74 had MP-KD. Complement C3 and CD4/CD8 ratio were significantly increased in MP-KD compared to KD. C3, C4, and the ratio of CD4/CD8 in the MP-KD group were higher than those in the MP-HSP group. IgA and CD56 were lower in the MP-KD group than the MP-HSP group.

CONCLUSIONS

Both C3 and polyclonal CD4+ T lymphocytes may be activated in the patients with MP-KD.

Serum immunoglobulin profiles in Chinese children with Henoch-Schönlein purpura

OBJECTIVE

The present study focuses on the associations of serum immunoglobulin with disease activity, relapse/recurrence and renal involvement in Henoch-Schönlein purpura (HSP) children.

METHODS

1683 Chinese children with HSP were recruited from January 2015 to January 2021. Laboratory data of blood samples and urine tests were collected. Renal biopsy was performed by the percutaneous technique. Patients' histories associated with HSP onset were obtained by interviews and questionnaires.

RESULTS

(1) IgA and IgE were dramatically elevated in HSP patients as compared with their normal values, and subject to a 1.75-3.09 fold and a 1.97-2.61 fold increase, respectively. (2) No significant correlation of the disease activity with IgA and IgE was determined, respectively. (3) The serum IgA levels were significantly lower in patients with relapse/recurrence than that in patients without relapse/recurrence, which may be attributed to the transmission of IgA-mediated immune complexes from blood to vessel walls. (4) No significant correlation was found between serum IgA, IgE levels and the pathological classification.

CONCLUSIONS

HSP children have marked disorders of serum immunoglobulin profiles, characterized by significant increases in IgA and IgE. The detection of serum IgA may be applicable to predict relapse/recurrence of HSP, whereas not associated with disease activity and renal involvement.

IgA vasculitis with nephritis: update of pathogenesis with clinical implications

IgA vasculitis with nephritis (IgAVN) shares many pathogenetic features with IgA nephropathy (IgAN). The purpose of this review is to describe our current understanding of the pathogenesis of pediatric IgAVN, particularly as it relates to the four-hit hypothesis for IgAN. These individual steps, i.e., hits, in the pathogenesis of IgAN are (1) elevated production of IgA1 glycoforms with some O-glycans deficient in galactose (galactose-deficient IgA1; Gd-IgA1), (2) generation of circulating IgG autoantibodies specific for Gd-IgA1, (3) formation of pathogenic circulating Gd-IgA1-containing immune complexes, and (4) kidney deposition of the Gd-IgA1-IgG immune complexes from the circulation and induction of glomerular injury. Evidence supporting the four-hit hypothesis in the pathogenesis of pediatric IgAVN is detailed. The genetics, pediatric outcomes, and kidney histopathologic features and the impact of these findings on future treatment and potential biomarkers are discussed. In summary, the evidence points to the critical roles of Gd-IgA1-IgG immune complexes and complement activation in the pathogenesis of IgAVN. Future studies are needed to characterize the features of the immune and autoimmune responses that enable progression of IgA vasculitis to IgAVN.

Serum TNF-α Level Is Associated with Disease Severity in Adult Patients with Immunoglobulin A Vasculitis Nephritis

Background

Tumor necrosis factor-α (TNF-α) is a proinflammatory factor involved in the pathogenesis of immunoglobulin A vasculitis (IgAV). The association between serum TNF-α and disease severity in adult patients with IgAV nephritis (IgAV-N) has been inadequately evaluated.

Methods

Serum TNF-α was measured by chemiluminescence immunoassay in 53 renal biopsy-proved IgAV-N patients, 53 healthy controls, and 53 IgA nephropathy (IgAN) patients. The correlations of clinicopathologic parameters of IgAV-N patients with serum TNF-α were analyzed.

Results

In this cross-sectional study, the median age of IgAV-N patients was 29 (25-37) years, and 67.9% were female. Serum TNF-α was significantly higher in the IgAV-N group than in the healthy group [7.4 (5.7-9.4) pg/mL vs. 5.9 (5.0, 7.1) pg/mL, P = 0.001], but comparable with sex, age, and estimated glomerular filtration rate (eGFR) grade-matched IgAN patients. Serum creatinine (P = 0.006) and serum cystatin C (P = 0.001) were positively correlated with serum TNF-α level, while albumin (P = 0.014) and eGFR (P = 0.021) were negatively correlated with serum TNF-α level. Multivariate linear regression analysis revealed that eGFR (P = 0.007) was an independent clinical predictor of serum TNF-α. Patients with higher pathological classification grade also had higher serum TNF-α.

Conclusions

Serum TNF-α is associated with renal function and the pathological classification of adult patients with IgAV-N. TNF-α is a potential biomarker for the assessment of IgAV-N severity.

Changes of inflammatory mediators and oxidative stress indicators in children with Henoch-Schönlein purpura and clinical effects of hemoperfusion in the treatment of severe Henoch-Schönlein purpura with gastrointestinal involvement in children

BACKGROUND

To explore the changes of inflammatory and oxidative stress responses in Henoch-Schönlein purpura (HSP) children, and further analyzed the therapeutic effects and mechanisms of hemoperfusion (HP) on HSP with severe gastrointestinal (GI) involvement.

METHODS

There were 200 children with HSP were divided into three groups according to their clinical manifestations: 60 in HSP without GI and renal involvement group, 60 in HSP with GI involvement group, and 80 in HSPN group. The HSP with GI involvement group was subdivided into conventional treatment (n = 30) and HP (n = 30) groups. Thirty children who visited the department of children healthcare for healthy physical examinations from January to December 2017 were set as healthy control group. The IL-6 and TNF-α levels were detected by chemoluminescence method. The MDA, SOD and T-AOC levels were determined by thiobarbituric acid colorimetric method, hydroxylamine method and chemical colorimetry.

RESULTS

Compared with healthy group, IL-6, TNF-α and MDA levels in HSP were increased in each group, while SOD and T-AOC were decreased (P = 0.000). IL-6, TNF-α and MDA levels in the HSPN group were the highest, SOD and T-AOC levels were the lowest (P = 0.000). Compared with those before treatment, IL-6, TNF-α and MDA levels in the conventional and HP groups were decreased and SOD and T-AOC levels were increased (P = 0.000). The changes in HP group were more significant than those in conventional group (P < 0.047). Compared with conventional group, glucocorticoid dosage and the occurrence rate of hematuria and/or proteinuria within 3 months were lower in HP group. (P = 0.000, 0.004).

CONCLUSIONS

Inflammatory and oxidative stress may be involved in the acute phase of HSP children. The intensity of inflammatory and oxidative stress responses were related to the degree of renal involvement. HP can reduce glucocorticoid dosage and the rate of renal involvement in children with severe HSP with GI involvement. The mechanism may be related to the fact that HP can effectively remove IL-6, TNF-α, MDA in HSP children.

[Clinical effect and mechanism of hemoperfusion in treatment of children with severe abdominal Henoch-Schönlein purpura]

OBJECTIVE

To study the clinical effect and mechanism of hemoperfusion (HP) in the treatment of children with severe abdominal Henoch-Schönlein purpura (HSP).

METHODS

A total of 24 children with severe abdominal HSP were divided into two groups: conventional treatment and HP (n=12 each). Ten healthy children who underwent physical examination were enrolled as the control group. Before and after treatment, chemiluminescence was used to measure the serum levels of interleukin-6 (IL-6) and tumor necrosis factor-&alpha; (TNF-&alpha;); thiobarbituric acid colorimetry was used to measure the plasma level of malondialdehyde (MDA); the hydroxylamine method was used to measure the plasma level of superoxide dismutase (SOD); chemical colorimetry was used to measure the plasma level of total anti-oxidant capability (T-AOC).

RESULTS

Compared with the control group, the conventional treatment and HP groups had significantly higher IL-6, TNF-&alpha;, and MDA levels and significantly lower SOD and T-AOC levels before treatment (P&lt;0.05), but there were no significant differences between the conventional treatment and HP groups (P&gt;0.05). After treatment, the conventional treatment and HP groups had significant reductions in IL-6, TNF-&alpha;, and MDA levels and significant increases in SOD and T-AOC levels (P&lt;0.05). The HP group had significantly greater changes than the conventional treatment group; however, there were still significant differences in these indices between the HP and control groups (P&lt;0.05). Compared with the HP group, the conventional treatment group had a significantly lower percentage of children with disappearance of digestive tract symptoms at 4 days after treatment and significantly longer time to disappearance of rash and digestive tract symptoms (P&lt;0.05). Compared with the conventional treatment group, the HP group had a significantly lower amount of glucocorticoid used during treatment and a significantly lower percentage of children who experienced hematuria and/or proteinuria within 6 months of the disease course (P&lt;0.05). There were no significant differences between the two groups in length of hospital stay and recurrence rates of rash and abdominal pain within 6 months of the disease course.

CONCLUSIONS

HP can reduce the amount of glucocorticoid used during treatment and the incidence rate of kidney injury in children with severe abdominal HSP, possibly by eliminating IL-6, TNF-&alpha;, and MDA.

Altered mean platelet volume in children with Henoch-Schonlein purpura and its association with disease activity

Background

Henoch-Schonlein purpura is a systemic small-vessel vasculitis that occurs mainly in children. A review of the literature has suggested a correlation between mean platelet volume and several inflammatory disorders. However, to the best of our knowledge, any potential correlation between mean platelet volume and Henoch-Schonlein purpura has not been reported in the literature. Therefore, our study aimed to evaluate the role of mean platelet volume concentrations in patients with Henoch-Schonlein purpura.

Methods

This study included 97 children with Henoch-Schonlein purpura and 120 healthy individuals as controls.

Results

Mean platelet volume concentrations were found to be significantly lower in Henoch-Schonlein purpura patients compared with healthy controls (8.1 ± 0.86 vs. 9.4 ± 0.81, P < 0.001). Similarly, significant negative correlations were observed between mean platelet volume and neutrophil count, platelet count and erythrocyte sedimentation rate in patients with Henoch-Schonlein purpura (r=−0.327, P = 0.001; r=−0.419, P < 0.001; r=−0.255, P = 0.012). Interestingly, mean platelet volume was significantly lower in the acute phase compared with the convalescent phase of Henoch-Schonlein purpura patients (7.8 ± 0.86 vs. 8.3 ± 0.77, P = 0.002). A cut-off value for mean platelet volume was 7.85 with area under the curve of 0.726 to identify acute phase vs. convalescent phase in patients with Henoch-Schonlein purpura. Mean platelet volume was independently associated with Henoch-Schonlein purpura in logistic regression analysis (odds ratio = 0.114, 95% confidence interval = 0.053–0.243, P < 0.001).

Conclusions

Our results suggest that mean platelet volume is inversely associated with disease in patients with Henoch-Schonlein purpura, and mean platelet volume may be a useful marker to identify active disease in Henoch-Schonlein purpura patients.

The Relationship of Neutrophil-Lymphocyte Ratio and Platelet-Lymphocyte Ratio with Gastrointestinal Bleeding in Henoch-Schonlein Purpura

Objectives

Henoch-Schonlein Purpura (HSP) is the most widespread systemic vasculitis during childhood. Gastrointestinal tract retention and gastrointestinal bleeding are among its major complications. Neutrophil-Lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) are indicators related to inflammatory diseases. This study evaluated the relationship between NLR or PLR and gastrointestinal bleeding in HSP.

Methods

The study consisted of 119 patients and 40 healthy children in the same age group. White Blood Cell (WBC) count, hemoglobin level, platelet count, mean platelet volume (MPV), neutrophil count and lymphocyte count were recorded. The NLR and PLR were calculated based on the results of complete blood count tests performed during the first visit to the hospital.

Results

The average neutrophil count and NLR of the patients with HSP were found to be significantly increased compared to the control group (P = 0.0001). No significant difference was observed between the PLR average of HSP and control groups (P = 0.053). Platelet count average (P = 0.0001) and PLR (P = 0.001) of the patients with gastrointestinal system (GIS) bleeding were found to be statistically significantly increased compared to those who did not have gastrointestinal bleeding. No significant difference was found in the NLR of the patients with and without gastrointestinal bleeding (P = 0.060).

Conclusions

While the NLR was significantly increased in patients with HSP in this study, the PLR was found to be more significant in patients with gastrointestinal bleeding. Similar to NLR, PLR may also be used as an inflammatory indicator among children with HSP, who have gastrointestinal bleeding.

Increased serum HMGB1 levels in patients with Henoch-Schönlein purpura

High-mobility group box-1 (HMGB1) has been implicated as a pro-inflammatory cytokine in the pathogenesis of various inflammatory and autoimmune diseases. However, information about HMGB1 in Henoch-Schönlein purpura (HSP) is still unclear. Herein, we investigated the role of HMGB1 in patients with HSP and the pro-inflammatory effects of HMGB1 on human dermal microvascular endothelial cell line (HMEC-1). Serum HMGB1 levels in patients with HSP together with patients with allergic vasculitis (AV) and urticarial vasculitis (UV) were detected by enzyme-linked immunosorbent assay (ELISA). HMEC-1 cells were treated with HMGB1 at concentrations ranging from 4 ng/ml to 100 ng/ml. Serum HMGB1 levels were significantly increased in patients with HSP, AV and UV, when compared with those in control group. Moreover, abundant cytoplasmic expression of HMGB1 was observed in endothelial cells in lesional skin of HSP patients. Using membrane cytokine antibody array, we indicate that HMGB1 markedly induced TNF-α and IL-6 release in cultured supernatant. Furthermore, by real-time quantitative PCR and ELISA, the effects of HMGB1 on these cytokines production in HMEC-1 cells were established. Finally, Western blot data revealed that HMGB1 can induce phosphorylation of inhibitor of κB-α (IκBα) and the nuclear translocation of nuclear factor-κB (NF-κB) p65 in HMEC-1 cells. In conclusion, this study provides first observations on the association of HMGB1 with HSP. We suggest that HMGB1 may be an important mediator of endothelial inflammation through the induction of TNF-α and IL-6 production and may play a crucial role in the pathogenesis of HSP.

An analysis of the levels of the soluble form of the endothelial protein C receptor in children with Henoch-Schönlein Purpura

The pathogenesis of Henoch-Schönlein Purpura (HSP) has not been clearly defined. Inflammatory cytokines have been associated with HSP but there are only a few reports that have focused on coagulation. The endothelial protein C receptor (EPCR), which has anticoagulant and antiinflammatory activity, is the key component of the protein C pathway. Recent studies have implicated the soluble form of EPCR (sEPCR) in Wegener's granulomatosis, Behçet's disease, and systemic lupus erythematosus. The aim of this study was to evaluate the levels of sEPCR in HSP children. Twenty-two children with HSP and 17 healthy children were included. We found no significant differences (P > .05) between patient and control groups in the levels of von Willebrand factor and thrombomodulin. The median sEPCR values in the HSP group were lower than the control group (79 vs. 102 ng/mL, respectively) (P > .05). The mean sEPCR value in HSP patients with severe abdominal pain was lower than without (88.8 ± 54.9 vs. 108.2 ± 66.3 ng/mL, respectively) (P > .05). In addition, the mean IL-6 serum levels were significantly elevated in HSP patients during the acute stage of HSP (2.1 ± 1.7 vs. 1.5 ± 1.2 pg/mL, P = .038). We also observed a slight negative correlation between the levels of sEPCR and IL-6 (R = -.135, P > .05). To our knowledge, this was the first study to analyze sEPCR levels in HSP. Our results did not conclusively identify a direct role of sEPCR in HSP, but our findings warrant further investigations, especially in severe HSP cases characterized by gastrointestinal bleeding or renal involvement.

Henoch-Schönlein purpura nephritis in children

Henoch-Schönlein purpura (HSP) is the most common vasculitis in children, in whom prognosis is mostly dependent upon the severity of renal involvement. Nephritis is observed in about 30% of children with HSP. Renal damage eventually leads to chronic kidney disease in up to 20% of children with HSP nephritis in tertiary care centres, but in less than 5% of unselected patients with HSP, by 20 years after diagnosis. HSP nephritis and IgA nephropathy are related diseases resulting from glomerular deposition of aberrantly glycosylated IgA1. Although both nephritides present with similar histological findings and IgA abnormalities, they display pathophysiological differences with important therapeutic implications. HSP nephritis is mainly characterized by acute episodes of glomerular inflammation with endocapillary and mesangial proliferation, fibrin deposits and epithelial crescents that can heal spontaneously or lead to chronic lesions. By contrast, IgA nephropathy normally presents with slowly progressive mesangial lesions resulting from continuous low-grade deposition of macromolecular IgA1. This Review highlights the variable evolution of similar clinical and histological presentations among paediatric patients with HSP nephritis, which constitutes a challenge for their management, and discusses the treatment of these patients in light of current guidelines based on clinical evidence from adults with IgA nephropathy.

Pentraxin 3 as a novel early biomarker for the prediction of Henoch-Schönlein purpura nephritis in children

We investigated the potential role of pentraxin 3 (PTX3) in Henoch-Schönlein purpura (HSP), a common multisystemic vasculitis affecting children, as a predictor of Henoch-Schönlein purpura nephritis (HSPN). A total of 108 cases consisting of 34 children with HSP, 37 children with HSPN, and 37 healthy control children were enrolled in this prospective study from March 2010 to February 2013. Blood and urine samples were collected to measure plasma PTX3, C-reactive protein (CRP), serum creatinine, blood urea nitrogen (BUN), urine microalbumin (MALB), and β2-microglobulin (β2-MG). Median plasma PTX3 concentrations were significantly higher in children with HSPN and HSP than in control subjects before treatment (6.99, 4.18-9.78 ng/ml; 3.19, 1.13-4.27 ng/ml; 1.24, 0.87-2.08 ng/ml, respectively; all p < 0.05). Median plasma PTX3 concentrations were also significantly higher in children with HSPN than in children with HSP before treatment (6.99, 4.18-9.78 vs. 3.19, 1.13-4.27 ng/ml; p < 0.05). After treatment, median plasma PTX3 concentrations significantly decreased in children with HSP (from 3.19, 1.13-4.27 to 1.08, 0.65-2.19 ng/ml; p < 0.05) and HSPN (from 6.99, 4.18-9.78 to 1.29, 1.01-2.26 ng/ml; p < 0.05). Plasma PTX3 concentration was positively correlated with CRP (rho = 0.532, p = 0.001), MALB (rho = 0.606, p < 0.001), β2-MG (rho = 0.490, p = 0.002), and 24-h urinary protein quantity (rho = 0.650, p < 0.001) in children with HSPN. Considering vasculitis, we found that PTX3 could be used as a more efficient potential predictor of HSPN than CRP as indicated by the area under the receiver operating characteristic (ROC) curve (AUCROC) of PTX3 (AUCROC = 0.837; p < 0.001) and CRP (AUCROC = 0.514; p = 0.845). The threshold PTX3 concentration with optimal sensitivity and specificity was 4.30 ng/ml (sensitivity 73.0 %, specificity 79.6 %).

CONCLUSION

PTX3 seems to have an important role in multisystemic vasculitis of HSP, may be involved in the development of HSPN, and used as an early biomarker to predict HSPN.

Effects of hemoperfusion in the treatment of childhood Henoch-Schönlein purpura nephritis

PURPOSE

Immune mediators play a role in the pathogenesis of Henoch-Schönlein purpura (HSP) nephritis. Since hemoperfusion (HP) is able to eliminate the immune mediators in many diseases, we investigated the effects of HP in the treatment of HSP nephritis.

METHODS

90 children with HSP nephritis were enrolled and followed up for 12 months. They were assigned to the HP group or the control group, respectively. Both groups were treated with corticosteroids and other supportive therapy. Patients in the HP group received HP for 3 consecutive days. The major outcomes included the percentage of patients with HSP nephritis, extrarenal symptoms, and recurrences and changes in serum levels of immune mediators.

RESULTS

The percentage of patients with nephritis in the HP group was less than that in the control group at each visit; the differences for prortions at 1, 3, 6, 12 months were 16.7% (p = 0.133), 31.3% (p = 0.004), 10.8% (p = 0.283), and 20.6% (p = 0.003), respectively. The severity and duration of abdominal and joint pains in the acute phase were significantly improved in the HP group compared to those in the control group. Hemoperfusion also significantly reduced patients' serum levels of immune mediators including IgA, TNF-α, IL-6, and LTB4. However, recurrences between the two groups were not significantly different.

CONCLUSIONS

Hemoperfusion in combination with corticosteroid was more effective than corticosteroid alone in treating HSP nephritis. The effects may be achieved by eliminating immune mediators.

Imbalance of interleukin-18 and interleukin-18 binding protein in children with Henoch-Schönlein purpura

The balance between interleukin-18 (IL-18) and its endogenous antagonist, IL-18 binding protein (IL-18BP), was evaluated in children with Henoch-Schönlein purpura (HSP). Plasma IL-18 and IL-18BP levels and peripheral blood mononuclear cell IL-18 mRNA expression were significantly higher in patients with active HSP (n = 30) than in healthy controls (n = 20); IL-18BP mRNA expression was similar in active HSP and controls. Plasma levels and mRNA expression of IL-18 and IL-18BP in patients in remission (n = 19) were similar to those in controls. The ratios of IL-18 / IL-18BP plasma levels and IL-18 / IL-18BP mRNA levels in active HSP were significantly higher than in patients in remission and healthy controls. Thus, adequate IL-18BP to block the proinflammatory activity of IL-18 may not be present in active HSP and regulation of the IL-18 / IL-18BP balance might provide a potential therapeutic strategy.

Urinary angiotensinogen levels in relation to renal involvement of Henoch-Schonlein purpura in children

AIM

To investigate whether urinary angiotensinogen (UAGT) levels are correlated with renal involvement of Henoch-Schonlein purpura (HSP) in children, and to explore whether UAGT has any relation to the severity of HSP.

METHODS

The study sample consisted of 107 patients (50 boys and 57 girls, 6.68±2.41 years) with clinical diagnosis of HSP. A 24 h urine sample was collected before treatment. UAGT levels were measured in patients with HSP in the acute and convalescent phases by enzyme linked immunosorbent assay.

RESULTS

Urinary angiotensinogen/urinary concentration of creatinine levels were significantly higher in proteinuric HSP in the acute phase and the convalescent phase (32.02±3.95 and 25.31±4.11 µg/g) compared with those with HSP without renal involvement (17.26±2.60 and 15.14±3.81 µg/g) and those with hematuric HSP (19.70±2.21 and 17.28±3.62 µg/g) (P<0.0001 and P<0.01, respectively). Using matched urine samples from the same patients, UAGT/urinary concentration of creatinine (UCr) levels of proteinuric HSP patients were significantly lower in the convalescent phase (25.31 ± 4.11 µg/g, P<0.01) than in the acute phase (32.02±3.95 µg/g). UAGT/UCr levels showed positive correlation with 24 h urine protein or serum creatinine in both hematuric HSP and proteinuric HSP groups during the acute phase (P<0.05).

CONCLUSIONS

Urinary angiotensinogen levels were remarkably high in the acute phase in the patients with proteinuric HSP, suggesting increased UAGT may indicate a series of functional changes in the kidney and it may be used as a potential biomarker of severity of HSP to monitor the progression of HSP with renal involvement.

Serum Interleukin-18 in Children with Henoch-Schönlein Purpura: A Promising Marker of Disease Activity?

Henoch-Schönlein purpura (HSp) is the most common systemic vasculitis of childhood with typical skin involvement and concurrent signs involving joints, gastrointestinal tract, and kidney. HSp pathogenesis is still far from being completely understood, though a knotty cytokine complex is believed to contribute to its intimate processes. The aim of our evaluation is to establish the relationship between serum levels of interleukin (IL)-18 and disease outcome and establish its feasibility to provide a marker of disease activity or even a prognostic tool in clinical practice. We examined clinical/laboratory variables and serum IL-18 in 17 children hospitalized during a year for HSp, diagnosed by EULAR/PRINTO/PRES criteria; the same patients were re-evaluated after 6 months. All results were compared with 25 age-matched healthy controls. IL-12 and IL-6 were also evaluated in a cohort of the same patients and compared with controls. General and clinical variables (sex, edema of the extremities, gastrointestinal or renal complications, relapses and renal involvement at 6 months) had no relationship with cytokine levels. Serum IL-18 and IL-6 levels were found significantly increased at diagnosis in HSp patients when compared with healthy controls. After 6 months, serum IL-18 and IL-12 levels were significantly decreased in patients, while IL-12 and IL-6 levels were significantly increased compared to healthy controls. Though preliminary and expecting further confirmation on a larger sample, our data support the conclusion that serum IL-18 levels reflect HSp activity.

Involvement of a disintegrin and metalloproteinase 10 and 17 in shedding of tumor necrosis factor-alpha

Tumor necrosis factor-alpha (TNF-alpha) is initially synthesized as a membrane-bound protein and converted into a soluble form by proteolytic cleavage. Although a disintegrin and metalloproteinase 17 (ADAM17) is considered to be the primary sheddase for TNF-alpha, it is not known whether ADAM17 is solely responsible for that process in any type of cells. To identify the TNF-alpha sheddase(s) in varieties of cells, we performed experiments using a unique screening system and observed that ADAM9, ADAM10, ADAM17, and ADAM19 were capable of cleaving TNF-alpha. We then performed RNA interference experiments and confirmed that ADAM10 and ADAM17 were in fact involved in TNF-alpha shedding in 293A cells. In mouse macrophages, ADAM17 was confirmed to be the primary sheddase, but the involvement of ADAM10 was also demonstrated. In NIH3T3 cells, ADAM10 could be more important in the shedding than ADAM17. In mouse vascular endothelial cell line UVfemale2, ADAM10 and ADAM17 were equally involved in TNF-alpha shedding, whereas ADAM17 was a major sheddase in human osteoarthritic chondrocytes. From these observations and others, we concluded that both ADAM10 and ADAM17 can be a TNF-alpha sheddase and that their significance could be determined by their expression levels and the abundance of tissue inhibitor of metalloproteinases.

Scrotal involvement in childhood Henoch-Schönlein purpura

AIM

Henoch-Schönlein purpura (HSP) is a common childhood systemic vasculitis involving the skin, gastrointestinal tract, joint, kidneys and even scrotum.

METHODS

We retrospectively reviewed the clinical and laboratory data of 120 male patients with HSP and also evaluated the risk factors for scrotal involvement and the relation between scrotal involvement and other clinical features. Twenty-six out of 120 boys (21.7%) diagnosed with HSP had scrotal involvement.

RESULTS

Scrotal symptoms manifested as swelling in 88.5% and pain (or tenderness) in 69.2% of HSP patients with scrotal involvement. Neurologic symptoms, mainly headache and localized edema among various manifestations and high serum C3 level of laboratory profiles were more frequently observed in scrotal-involved group than in those of non-involved group. However, there was no difference in the outcomes of scrotal symptoms according to therapeutic modalities and the occurrence of scrotal involvement had no correlation with renal involvement from acute to chronic phase.

CONCLUSIONS

We found that neurologic symptoms, localized edema and high serum C3 level show a significant relation with scrotal involvement in male HSP patients. Because scrotal involvement in male HSP patients is not rare, the accurate early diagnosis of HSP is mandatory by the early notification of purpura and imaging evaluations in order to avoid unnecessary procedures.

Henoch-Schonlein purpura: polymorphisms in thrombophilia genes

Henoch-Schonlein purpura (HSP) is a small-sized vasculitis affecting mainly children. Based on the hypothesis that an inherited predilection to hypercoagulability may predispose to HSP or may mark those who develop acute clinical manifestations, we evaluated the possible roles of methylenetetrahydrofolate reductase (MTHFR) gene C677T, factor V (FV) gene G1691A (Leiden), and prothrombin gene G20210A polymorphisms in patients with HSP. Fifty-two HSP patients (32 boys and 20 girls) from different ethnic groups (22 Jews and 30 Arabs) and 104 ethnically matched controls were studied for these three polymorphisms. The frequencies of these mutations for each group, separately and in combinations, are described. The mutation frequencies in the MTHFR, prothrombin and FV genes in HSP patients did not differ from those in controls. In a small number of individuals (n=5) homozygosity for the 677T thermolabile variant of MTHFR was associated with hematuria. To summarise, hypercoagulability does not seem to play a role in HSP. Studies in larger cohorts and possibly inclusion of additional factors may be needed to ascertain whether homozygoty for MTHFR 677T polymorphism can influence disease severity.

Changes in angiopoietin expression in glomeruli involved in glomerulosclerosis in rats with daunorubicin-induced nephrosis

AIM

To study the potential pathological role of endogenous angiopoietins in daunorubicin-induced progressive glomerulosclerosis in rats.

METHODS

Seventy male Wistar rats were allocated randomly into a daunorubicin group (DRB; n=40) or a control group (n=30). The rats in the DRB group were injected with DRB (15 mg/kg), in their tails. Subsequently, at intervals of 1, 2, 4, 6, 8, and 12 weeks, 5 male Wistar rats in each group were chosen randomly for 24 h urinary protein quantitative measurements (24 h UPQM), and determination of plasma tumor necrosis factor alpha (TNF-alpha), angiopoietin-1 (Ang1), and angiopoietin-2 (Ang2) levels. Kidney sections were examined by electron microscopy, Periodic Acid Schiff (PAS) staining, immunohistochemical staining and in situ hybridization histochemistry.

RESULTS

As glomerulosclerosis progressed in the DRB group, expression of Ang1 mRNA and protein in glomeruli decreased and expression of TNF-alpha protein, Ang2 mRNA and protein in glomeruli increased. Expression of Ang1 mRNA and protein in glomeruli were negatively correlated with 24 h UPQM, Fn protein expression, and mean area of extracellular matrix (MAECM). In comparison, expression of Ang2 mRNA and protein in glomeruli were positively correlated with 24 h UPQM, Fn protein expression and MAECM; furthermore, there was a positive correlation between plasma Ang2 and 24 h UPQM. Plasma TNF-alpha and expression of TNF-alpha in glomeruli were positively correlated with expression of Ang2 mRNA and protein in glomeruli. There was a negative correlation between Ang1 protein expression and Ang2 protein expression in glomeruli.

CONCLUSION

During DRB-induced glomerulosclerosis, podocyte injury led to a shift in the balance of Ang1 and Ang2 in glomeruli. Increased TNF-alpha in plasma and glomeruli may upregulate Ang2 expression in glomeruli. Elevated Ang2 in both plasma and glomeruli may mediate protein permeability through the glomerular filtration barrier. Moreover, local expression of Ang2 may facilitate the progress of glomerulosclerosis by upregulating a component expression of extracellular matrix.