Cell surface expression of nucleolin mediates the antiangiogenic and antitumor activities of kallistatin.

Kallistatin is a unique serine proteinase inhibitor and heparin-binding protein. A previous study conducted by our group indicated that kallistatin has antiangiogenic and antitumoral activities. In the present study, we report that kallistatin specifically binds to membrane surface-expressed nucleolin with high affinity. Antibody-mediated neutralization or siRNA-induced nucleolin knockdown results in loss of kallistatin suppression of endothelial cell proliferation and migration in vitro and tumor angiogenesis and growth in vivo. In addition, we show that kallistatin is internalized and transported into cell nuclei of endothelial cells via nucleolin. Within the nucleus, kallistatin inhibits the phosphorylation of nucleolin, which is a critical step required for cell proliferation. Thus, we demonstrate that nucleolin is a novel functional receptor of kallistatin that mediates its antiangiogenic and antitumor activities. These findings provide mechanistic insights into the inhibitory effects of kallistatin on endothelial cell growth, tumor cell proliferation, and tumor-related angiogenesis.

[Effects of sublingual immunotherapy on serum IL-17 and IL-35 levels in children with allergic rhinitis or asthma].

OBJECTIVE: To study the clinical effect and mechanisms of specific sublingual immunotherapy (SLIT) for the treatment of allergic rhinitis or asthma in children. METHODS: Thirty children suffering from Dermatophagoides farinae-allergic rhinitis or asthma (case group) and 30 healthy children (control group) were enrolled in this study. The case group accepted SLIT between January and December 2011. The ratio of forced expiratory volume in one second (FEV1) and its expected value, the ratio of airway resistance and its expected value, peripheral blood eosinophil (Eos) count and serum levels of IL-17 and IL-35 were measured before treatment and one and two years after treatment. The rhinitis or asthma symptom scores were rated and the level of asthma control was monitored. RESULTS: Serum IL-17 level in the case group was significantly higher than in the control group before treatment and one year after treatment (P<0.01). Furthermore, serum IL-17 level in the case group gradually decreased from before treatment to 1 year to 2 years after treatment (P<0.01). By two years of treatment, there was no significant difference in serum IL-17 level between the case and control groups (P>0.05). The changes of serum IL-35 level after treatment were opposite to serum IL-17 in the case group. The ratio of FEV1 and its expected value gradually increased from before treatment to 1 year to 2 years after treatment (P<0.01) in the case group. In contrast, the change of the ratio of airway resistance and its expected value and Eos count gradually decreased from before treatment to 1 year to 2 years after treatment (P<0.01) in the case group. More patients achieved improved rhinitis or asthma symptom scores two years after treatment than one year after treatment in the case group (P<0.01). SLIT was effective in 85% of children with allergic rhinitis one after treatment vs 100% two years after treatment. Asthma control was observed in 76% of the asthmatic patients one after treatment vs 92% two years after treatment. CONCLUSIONS: SLIT is effective for allergic rhinitis and asthma in children, and the treatment period of two years seems to be superior to one year. The mechanism of action of SLIT for the treatment of allergic rhinitis and asthma may be associated with inhibition of IL-17 expression and promotion of IL-35 expression.

[Application of bacterial cultures of bronchoalveolar lavage fluids in children with pulmonary infection].

OBJECTIVE: To study the value of bacterial cultures of bronchoalveolar lavage fluids (BALF) in children with pulmonary infection. METHODS: Bacterial cultures sampled from both sputum and BALF were performed on 80 hospitalized children with pulmonary infection between June 2008 and February 2011.Culture results between the two samples were compared. RESULTS: In the 80 children with pulmonary infection, bacterial cultures of BALF showed that Viridans Streptococci were found in 72 cases (90%), Neisseria in 41 cases (51%), Streptococcus pneumoniae in 11 cases (14%), Staphylococcus Aureus in 3 cases (4%) and Escherichia coli in 3 cases (4%). The positive rates of Viridans Streptococci in the bacterial cultures of BALF was not significantly different from the bacterial cultures of sputum, but the positive rate of Streptococcus pneumoniae in the bacterial cultures of BALF was significantly higher than in the bacterial cultures of sputum (4%). Moreover, Escherichia coli were found only by bacterial cultures of BALF. CONCLUSIONS: Bacterial cultures of BALF are useful in the identification of pathogenic bacteria for pulmonary infection in children. Due to the samples taken from the lesion regions in bacterial cultures of BALF, the results of may be more reliable.

[Role of mast cells in the development of renal interstitial fibrosis in children with Henoch-Schonlein purpura nephritis].

OBJECTIVE: To investigate the role of mast cells in the development of renal interstitial fibrosis in children with Henoch-Schonlein purpura nephritis (HSPN) and possible mechanisms. METHODS: Paraffin-embedded renal biopsy tissue sections from 20 children with HSPN were examined for the levels of tryptase-beta and transforming growth factor-beta1 (TGF-beta1) by immunohistochemical staining. Mast cells were counted by toluidine blue staining. Masson staining was used to assess the level of renal interstitial fibrosis and renal histopathological scores. Normal renal tissue sections from 5 nephrectomized children for nephroma were used as control group. RESULTS: The percentages of positive tryptase-beta cellsand mast cells and the TGF-beta1 expression in the HSPN group were significantly higher than those in the control group (P < 0.05). The percentages of positive tryptase-beta cells and mast cells and the TGF-beta1 expression in renal tissue were positively correlated with the glomeruli histopathological score (r =0.940, 0.920, 0.937, respectively; P < 0.05) and were also positively correlated with the histopathological score of renal interstitium (r=0.903, 0.859, 0.948, respectively; P < 0.05). The level of renal interstitial fibrosis was positively correlated with the percentages of positive tryptase-beta cells and mast cells and the expression of TGF-beta1 (r =0.790, 0.766, 0.858, respectively; P < 0.05). There was a positive correlation between the percentages of positive tryptase-beta cells and mast cells (r =0.941, P < 0.05), between the percentage of positive tryptase-beta cells and the TGF-beta1 expression (r =0.897, P < 0.05) and between the percentage of positive mast cells and the TGF-beta1 expression (r=0.942, P < 0.05). CONCLUSIONS: Tubulointerstitial mast cell infiltration is associated with the development of renal interstitial fibrosis in children with HSPN. Mast cells together with TGF-beta1 and mast cell-derived tryptase-beta may be involved in the development of the renal interstitial fibrosis in HSPN.