Ultrasound assisted hot water extraction of polysaccharides from Taraxacum mongolicum: Optimization, purification, structure characterization, and antioxidant activity.

Ultrasound assisted hot water extraction (UAHWE) was applied to extraction of polysaccharides from Taraxacum mongolicum with hot water as extract solvent. Experimental factors in UAHWE process were optimized by response surface methodology. The optimal extraction parameters to achieve the highest Taraxacum mongolicum polysaccharides (TMPs) yield (12.08 ± 0.14)% by UAHWE were obtained under the ultrasound power of 200 W, extraction temperature of 62°C, solid-to-liquid ratio of 1:20 g/mL, and extraction time of 40 min, and then the crude TMPs were further purified by DEAE-52 and Sephadex G-100 chromatography to obtain a homogenous polysaccharide fraction (TMPs-1-SG). Subsequently, the structure of TMPs-1-SG was characterized by UV-vis, Fourier transform infrared spectroscopy (FT-IR), high performance gel permeation chromatography (HPGPC), high performance liquid chromatography (HPLC), scanning electron microscope (SEM), transmission electron microscopy (TEM), and Congo red test. The results display that TMPs-1-SG with an average molecular weight of 5.49 × 104 Da was comprised of mannose (Man), galactose (Gal), xylose (Xyl), and arabinose (Ara) with a molar ratio of 39.85:52.61:27.14:6.30. Moreover, TMPs-1-SG did not contain a triple helix structure. Furthermore, TMPs-1-SG and TEM presented a sheet-like, rod-shaped, and irregular structure. Finally, the antioxidant activity of TMPs-1-SG was evaluated by in vitro experiment. The IC50 values of scavenging DPPH and OH radicals for TMPs-1-SG achieved 0.71 mg/mL and 0.75 mg/mL, respectively. The findings can provide an effective method for extracting polysaccharides from natural resources.

Enhancement of Macrophage Immunity against Chlamydial Infection by Natural Killer T Cells.

Lung macrophage (LM) is vital in host defence against bacterial infections. However, the influence of other innate immune cells on its function, including the polarisation of different subpopulations, remains poorly understood. This study examined the polarisation of LM subpopulations (monocytes/undifferentiated macrophages (Mo/Mφ), interstitial macrophages (IM), and alveolar macrophages (AM)). We further assessed the effect of invariant natural killer T cells (iNKT) on LM polarisation in a protective function against Chlamydia muridarum, an obligate intracellular bacterium, and respiratory tract infection. We found a preferentially increased local Mo/Mφ and IMs with a significant shift to a type-1 macrophage (M1) phenotype and higher expression of iNOS and TNF-α. Interestingly, during the same infection, the alteration of macrophage subpopulations and the shift towards M1 was much less in iNKT KO mice. More importantly, functional testing by adoptively transferring LMs isolated from iNKT KO mice (iNKT KO-Mφ) conferred less protection than those isolated from wild-type mice (WT-Mφ). Further analyses showed significantly reduced gene expression of the JAK/STAT signalling pathway molecules in iNKT KO-Mφ. The data show an important role of iNKT in promoting LM polarisation to the M1 direction, which is functionally relevant to host defence against a human intracellular bacterial infection. The alteration of JAK/STAT signalling molecule gene expression in iNKT KO-Mφ suggests the modulating effect of iNKT is likely through the JAK/STAT pathway.

Development and validation of a prognostic nomogram model incorporating routine laboratory biomarkers for preoperative patients with endometrial cancer.

BACKGROUND: Some biomarkers collected from routine laboratory tests have shown important value in cancer prognosis. The study aimed to evaluate the prognostic significance of routine laboratory biomarkers in patients with endometrial cancer (EC) and to develop credible prognostic nomogram models for clinical application. METHODS: A total of 727 patients were randomly divided into a training set and a validation set. Cox proportional hazards models were used to evaluate each biomarker's prognostic value, and independent prognostic factors were used to generate overall survival (OS) and progression-free survival (PFS) nomgrams. The efficacy of the nomograms were evaluated by Harrell's concordance index (C-index), receiver operating characteristic (ROC) curves, decision curve analysis (DCA), calibration curves, X-tile analysis and Kaplan‒Meier curves. RESULTS: Ten significant biomarkers in multivariate Cox analysis were integrated to develop OS and PFS nomograms. The C-indices of the OS- nomogram in the training and validation sets were 0.885 (95% confidence interval (CI), 0.810-0.960) and 0.850 (95% CI, 0.761-0.939), respectively; those of the PFS- nomogram in the training and validation sets were 0.903 (95% CI, 0.866-0.940) and 0.825 (95% CI, 0.711-0.939), respectively. ROC, DCA and calibration curves showed better clinical application value for the nomograms incorporating routine laboratory biomarkers. X-tile analysis and Kaplan‒Meier curves showed that the nomograms were stable and credible in evaluating patients at different risks. CONCLUSIONS: Nomogram models incorporating routine laboratory biomarkers, including NLR, MLR, fibrinogen, albumin and AB blood type, were demonstrated to be simple, reliable and favourable in predicting the outcomes of patients with EC.

Circadian rhythm-related factors of PER and CRY family genes function as novel therapeutic targets and prognostic biomarkers in lung adenocarcinoma.

The period (PER) and cryptochrome (CRY) families play critical roles in circadian rhythms. The imbalance of circadian factors may lead to the occurrence of cancer. Expressions of PER and CRY family members decrease in various cancers. Nevertheless, expression levels, genetic variations, and molecular mechanisms of PER and CRY family members in lung adenocarcinoma (LUAD) and their correlations with prognoses and immune infiltration in LUAD patients are still unclear. In this study, to identify their biological functions in LUAD development, comprehensive high-throughput techniques were applied to analyze the relationships of expressions of PER and CRY family members with genetic variations, molecular mechanisms, and immune infiltration. The present results showed that transcription levels of PER1 and CRY2 in LUAD were significantly downregulated. High expression levels of PER2, PER3, CRY1, and CRY2 indicated longer overall survival. Some cancer signaling pathways were related to PER and CRY family members, such as cell-cycle, histidine metabolism, and progesterone-mediated oocyte maturation pathways. Expressions of PER and CRY family members significantly affected the infiltration of different immune cells. In conclusion, our findings may help better understand the molecular basis of LUAD, and provide new perspectives of PER and CRY family members as novel biomarkers for LUAD.

Selective Anti-melanoma Effect of Phosphothioated Aptamer Encapsulated by Neutral Cytidinyl/Cationic Lipids.

BC15-31 is a DNA aptamer that targets heterogeneous nuclear ribonucleoprotein A1 (hnRNP A1), which plays a crucial role in the process of pre-RNA maturation and is also essential for the rapid proliferation of tumor cells. In this research, we modified BC15-31 with a phosphorothioate (PS) backbone, LNA, and 2-O-MOE to enhance its stability and target affinity. In addition, a neutral cytidinyl lipid (DNCA) and a cationic lipid (CLD) were mixed to encapsulate modified aptamers with the aim of improving their cell permeability with low toxicity. Under the DNCA/CLD package, aptamers are mainly distributed in the nucleus. A modified sequence WW-24 showed an excellent selective anti-melanoma (A375 cells, ∼25 nM, 80%) activity, targeted to both hnRNP A1 and hnRNP A2/B1 found by the BLI experiment, and induced more early and late apoptosis in vitro, which also showed stronger antitumor effect and longer accumulation time in vivo. These results provide a new strategy for further clinical applications.

Overcoming the delivery barrier of oligonucleotide drugs and enhancing nucleoside drug efficiency: The use of nucleolipids.

With the rapid development of synthetic technology and biological technology, many nucleic acid-based drugs have entered the clinical trials. However, their inherent disabilities in actively and efficiently penetrating cell membranes still severely restrict their further application. The main drawback of cationic lipids, which have been widely used as nonviral vectors of nucleic acids, is their high cytotoxicity. A series of nucleoside-based or nucleotide-based nucleolipids have been reported in recent years, due to their oligonucleotide delivery capacity and low toxicity in comparison with cationic lipids. Lipophilic prodrugs of nucleoside analogs have extremely similar structures with nucleolipid vectors and are thus helpful for improving the transmembrane ability. This review introduces the progress of nucleolipids and provides new strategies for improving the delivery efficiency of nucleic acid-based drugs, as well as lipophilic prodrugs of nucleosides or nucleotides for antiviral or anticancer therapies.

The Important Role of Dendritic Cell (DC) in iNKT-Mediated Modulation of NK Cell Function in Chlamydia pneumoniae Lung Infection.

Chlamydia pneumoniae (Cpn) infection causes multiple acute and chronic human diseases. The role of DCs in host defense against Cpn infection has been well documented. The same is true for invariant natural killer T (iNKT) cells and NK cells, but the interaction among cells is largely unknown. In this study, we investigated the influence and mechanism of iNKT cell on the differentiation and function of NK cell in Cpn lung infection and the role played by DCs in this process. We found that expansion of IFN-γ-producing NK cells quickly happened after the infection, but this response was altered in iNKT knockout (KO) mice. The expression of activation markers and the production of IFN-γ by different NK subsets were significantly lower in KO mice than wild-type (WT) mice. Using in vitro DC-NK coculture and in vivo adoptive transfer approaches, we further examined the role of DCs in iNKT-mediated modulation of NK cell function. We found that NK cells expressed lower levels of activation markers and produced less IFN-γ when they were cocultured with DCs from KO mice than WT mice. More importantly, we found that the adoptive transfer of DCs from the KO mice induced less NK cell activation and IFN-γ production. The results provided evidence on the modulating effect of iNKT cell on NK cell function, particularly the critical role of DCs in this modulation process. The finding suggests the complexity of cellular interactions in Cpn lung infection, which should be considered in designing preventive and therapeutic approaches for diseases and infections.

Structural optimization and additional targets identification of antisense oligonucleotide G3139 encapsulated in a neutral cytidinyl-lipid combined with a cationic lipid in vitro and in vivo.

Antisense oligonucleotides (ASOs) usually contain a fully phosphorothioate (PS) backbone, which possibly interact with many genes and proteins under intracellular conditions. G3139 is an ASO that targets Bcl-2 mRNA and induces cell apoptosis. Here, we report a kind of cytidinyl-lipid combined with a cationic lipid (DNCA/CLD, molar ration, 28:3, named mix), which may interact with oligonucleotides via H-bond formation, pi-stacking and electrostatic interaction, accompanied by low zeta potentials. The IC50 value of G3139 delivered by mix-lipid reduced from above 20 µM to 0.158 µM for MCF-7/ADR, and exhibited stronger antiproliferation upon other cancer cell lines. In addition, PS modification in the 3'-half of G3139 (especially at positions 13-16) enhanced serum stability, target specificity and anticancer activity. Also, a locked nucleic acid (LNA) gapmer G3139 (LNA-G3139) showed superior antiproliferation (78.5%) and Bcl-2 mRNA suppression effects (85.5%) at 200 nM, mainly due to its high complementary RNA affinity. More apoptosis-associated targets were identified, and a lower level of non-specific protein binding (HSA) revealed that both antisense and aptamer mechanisms might simultaneously exist. A combination of a new delivery system and chemical modifications, such as in LNA-G3139, may have potential clinical application prospects in the future.

Annealing novel nucleobase-lipids with oligonucleotides or plasmid DNA based on H-bonding or π-π interaction: Assemblies and transfections.

Lipid derivatives of nucleoside analogs have been highlighted for their potential for effective gene delivery. A novel class of nucleobase-lipids are rationally designed and readily synthesized, comprising thymine/cytosine, an ester/amide linker and an oleyl lipid. The diversity of four nucleobase-lipids termed DXBAs (DOTA, DNTA, DOCA and DNCA) is investigated. Besides, DNCA is demonstrated to be an effective neutral transfection material for nucleic acid delivery, which enbles to bind to oligonucleotides via H-bonding and π-π stacking with reduced toxicity in vitro and in vivo. Several kinds of nucleic acid drugs including aptamer, ssRNA, antisense oligonucleotide, and plasmid DNAs can be delivered by DXBAs, especially DNCA. In particular, G4-aptamer AS1411 encapsulated by DNCA exhibits cellular uptake enhancement, lysosome degradation reduction, cell apoptosis promotion, cell cycle phase alteration in vitro and duration prolongation in vivo, resulting in significant anti-proliferative activity. Our results demonstrate that DNCA is a promising transfection agent for G4-aptamers and exhibites bright application prospects in the permeation improvement of single-stranded oligonucleotides or plasmid DNAs.

Contribution of PGR genetic polymorphisms to the pathogenesis of endometrial cancer: A meta-analysis.

OBJECTIVE: The aim of this meta-analysis is to identify whether two common genetic polymorphisms (rs1042838 G > T and rs10895068 C > T) in the PGR gene may contribute to the pathogenesis of endometrial cancer. MATERIALS AND METHODS: The MEDLINE (1966 ~ 2013), the Cochrane Library Database (Issue 12, 2013), EMBASE (1980 ~ 2013), CINAHL (1982 ~ 2013), Web of Science (1945 ~ 2013) and the Chinese Biomedical Database (CBM) (1982 ~ 2013) were searched without language restrictions. Meta-analyses were conducted using the STATA software (Version 12.0, Stata Corporation, College Station, Texas, USA). We calculated odds ratio (OR) and its 95% confidence interval (95% CI) to estimate the relationships between PGR genetic polymorphisms and the pathogenesis of endometrial cancer. RESULTS: Six studies with a total of 6,285 patients with endometrial cancer and 12,120 control subjects met the inclusion criteria for the meta-analysis. Our findings suggested that PGR rs1042838 polymorphism was significantly correlated with an increased risk of endometrial cancer (T allele vs. G allele: OR = 1.23, 95% CI: 1.07 ~ 1.42, P = 0.005; GT + TT vs. GG: OR = 1.21, 95% CI: 1.06 ~ 1.40, P = 0.006; TT vs. GG + GT: OR = 1.65, 95% CI: 1.09 ~ 2.49, P = 0.017; TT vs. GG: OR = 1.72, 95% CI: 1.12 ~ 2.65, P = 0.013; TT vs. GT: OR = 1.42, 95% CI: 1.01 ~ 2.00, P = 0.044, respectively). We also observed positive associations between PGR rs10895068 polymorphism and the pathogenesis of endometrial cancer (T allele vs. C allele: OR = 1.15, 95% CI: 1.02 ~ 1.29, P = 0.027; CT + TT vs. CC: OR = 1.14, 95% CI: 1.00 ~ 1.29, P = 0.045, respectively). CONCLUSION: Ethnicity-stratified analysis indicated that rs1042838 and rs10895068 polymorphisms in the PGR gene might be strongly related to the pathogenesis of endometrial cancer among Caucasians and mixed populations (all P < 0.05). In conclusion, our findings provide empirical evidence that PGR rs1042838 and rs10895068 polymorphisms may be involved in the pathogenesis of endometrial cancer.

Correlation of the expression of vascular endothelial growth factor and its receptors with microvessel density in ovarian cancer.

The present study aimed to investigate the correlation between the expression of vascular endothelial growth factor (VEGF) and its receptors, the Flt-1 and KDR proteins, with clinical pathology and microvessel density (MVD) in ovarian cancer tissue. The protein expression levels of VEGF and its receptors, Flt-1 and KDR/Flk-1, were detected in 48 cases of ovarian cancer using the streptavidin-biotin complex (SABC) immunohistochemical method, and tumor MVD was evaluated using F8 factor (FVIII-RA). The expression of the VEGF, Flt-1 and KDR proteins was not significantly associated with the pathological type, extent of differentiation or clinical stage of ovarian cancer. However, the co-expression of VEGF and Flt-1 was markedly correlated with differentiation and clinical stage (P<0.01). The co-expression levels of VEGF and receptor Flt-1 in malignant neoplasms with lymph node metastasis was significantly higher compared with malignant neoplasms without lymph node metastasis (P<0.05). The expression level of KDR in patients with hepatic metastasis was significantly higher compared with patients without hepatic metastasis (P<0.05). The co-expression level of VEGF and KDR in patients with hepatic metastasis was significantly higher compared with patients without hepatic metastasis (P<0.05) and the Flt-1 expression level in patients with ascites <1,000 ml was significantly lower than that in patients with ascites ≥1000 ml (P<0.05). The mean MVD of VEGF- and KDR-positive patients was significantly higher compared with VEGF- and KDR-negative patients (P<0.05). The expression of VEGF and its receptors is involved in the malignant transformation of ovarian tumors, tumor progression and metastasis, as well as ascites formation and angiogenesis.

Differential modulating effect of natural killer (NK) T cells on interferon-γ production and cytotoxic function of NK cells and its relationship with NK subsets in Chlamydia muridarum infection.

Natural killer T (NKT) cells are a newly identified T-cell population with potential immunomodulatory functions. Several studies have shown modulating effects of NKT cells activated by α-galactosylceramide, a model antigen, on NK cell function. We here report a differential modulating effect of NKT cells on the interferon-γ (IFN-γ) production and cytolytic function of NK cells in a chlamydial infection model, using NKT-cell-deficient mice and antibody blocking (anti-CD1d monoclonal antibody) approaches. Our results showed that both NKT and NK cells became activated and produced IFN-γ following Chlamydia muridarum infection in vitro and in vivo. The NK cells in NKT-cell-deficient mice and CD1d-blocked mice showed decreased CD69 expression, cellular expansion and IFN-γ production but surprisingly showed increased cytolytic activity (degranulation) of immature and more mature NK cell subsets, suggesting an inhibitory role of NKT cells on NK cell killing activity. The results suggest that NKT cells preferentially promote IFN-γ production but are inhibitory for the cytotoxic function of NK cells in this infection model. Furthermore, the differential modulating effect of NKT cells on the IFN-γ production and cytotoxicity of NK cells was observed in immature and mature NK cell subsets, although it was more dramatic in the relatively mature CD11b(high) CD27(high) NK cell subset. This finding demonstrates the complexity of innate cell interactions in infection and the possible differential impact of NKT cells on the variable functional aspects of other cell(s) even in one infection setting.

Autophagy modification augmented the treatment effects initiated by arsenic trioxide in NB4 cells.

Autophagy is a survival pathway required for cellular viability during starvation through catabolic self-digestion of damaged proteins and organelles; however, autophagy may result in cell death if it proceeds to completion. Although the exact mechanism of this process is not clear, it seems that proper regulation of autophagy can potentially contribute to the therapeutics of cancers. This study was designed to examine the role of autophagy in the death of human acute promyelocytic leukemia NB4 cells initiated by arsenic trioxide. Furthermore, the effects of autophagy inhibition and augmentation on cell viability were also compared. Our data suggested that both augmentation and suppression of autophagy could enhance the treatment effects while the latter was preferable. This study indicated that autophagy regulation augmented the treatment effects initiated by arsenic trioxide in NB4 cells, and that the selection of regulator should be precisely considered.

Relationship of adiponectin and resistin levels in umbilical serum, maternal serum and placenta with neonatal birth weight.

OBJECTIVE: Adiponectin and resistin have been postulated to play a role in the regulation of energy metabolism during pregnancy. However, relationship of adiponectin and resistin levels in umbilical serum, maternal serum and placenta with neonatal birth weight remains to be poorly understood. The purpose of the study was to clarify the correlations between adiponectin and resistin levels and neonatal birth weight. METHODS: Enzyme immunoassay was used to measure the adiponectin and resistin levels in maternal and umbilical serum from 40 normal pregnant women (control group), 30 women with macrosomia (macrosomia group) and 30 women with fetal growth restriction (FGR group). Immunohistochemistry was used to measure adiponectin and resistin levels in placenta. RESULTS: Serum adiponectin and resistin levels were significantly increased in control women compared with that in macrosomia mothers, but significantly decreased compared with that in FGR mothers. The levels of adiponectin and resistin in control babies were significantly higher than that in macrosomic babies, whereas significantly lower than that in FGR babies. The placental expressions of adiponectin and resistin in macrosomia, control and FGR group were gradually elevated, and there was a significant difference between them. Umbilical serum adiponectin levels and placental adiponectin expression were inversely correlated with birth weight. Umbilical serum levels and placental expression of resistin had positive correlation with maternal serum resistin and negative correlation with birth weight. In addition, maternal serum resistin levels were inversely correlated with birth weight. CONCLUSION: It is suggested that adiponectin and resistin play an important role in controlling body weight and may be related to the occurrence of fetal macrosomia and FGR.

Relationship of adiponectin and resistin levels in umbilical and maternal serum with fetal macrosomia.

AIM: Adiponectin and resistin are novel hormones secreted by human adipocytes and mononuclear cells, which have been postulated to play roles in the regulation of energy metabolism during pregnancy. However, correlations between adiponectin and resistin levels in umbilical and maternal serum and fetal macrosomia remain poorly understood. The purpose of this study was to clarify the relationship of adiponectin and resistin levels in umbilical and maternal serum with fetal macrosomia. METHODS: Serum adiponectin and resistin levels were prospectively measured by enzyme immunoassay in 70 mothers and their 70 neonates. The study group included 30 neonates with macrosomia and the control group included 40 neonates that were appropriate for gestational age. The correlations of cord serum adiponectin and resistin with maternal serum adiponectin and resistin, birth weight, body mass index (BMI), and placental weight were analyzed. RESULTS: Serum adiponectin and resistin levels were significantly decreased in macrosomic mothers compared with those in control women. The levels of adiponectin and resistin were diminished in macrosomic babies in comparison with control newborns. Umbilical serum adiponectin levels were inversely correlated with birth weight, newborn BMI, and placental weight, but not with maternal serum adiponectin levels. Umbilical serum resistin levels had a positive correlation with maternal serum resistin and a negative correlation with birth weight, newborn BMI, and placental weight. In addition, maternal serum resistin levels were inversely correlated with newborn birth weight. CONCLUSION: It is suggested that adiponectin and resistin play important roles in controlling body weight and may be related to the occurrence of fetal macrosomia.

Effect of phthalate esters on the secretion of prostaglandins (F2alpha and E2) and oxytocin in cultured bovine ovarian and endometrial cells.

The influence of phthalate esters di-2-ethylhexyl phthalate (DEHP) and mono-2-ethylhexyl phthalate (MEHP) on uterine prostaglandin (PGF2alpha and PGE2) and ovarian oxytocin secretion was investigated. Endometrial, granulosa, and luteal cells from cows on days 8-12 of the estrous cycle were treated with DEHP or MEHP (0.1, 1, or 10 ng/mL). We found that DEHP and MEHP stimulated (P < 0.05) secretion of PGF2alpha and inhibited (P < 0.001) secretion of PGE2 from endometrial cells. The ratio of PGF2alpha to PGE2 was markedly altered. The endocrine disrupting chemicals also enhanced secretion of oxytocin (P < 0.05) from ovarian cells. Our results indicated that DEHP and its metabolite MEHP could affect the process of the estrous cycle by impairing secretion of prostaglandin from the uterus and oxytocin from the ovary.

Type I IFNs enhance susceptibility to Chlamydia muridarum lung infection by enhancing apoptosis of local macrophages.

Type I IFNs (IFNIs) have pleiotropic functions in regulating host innate and adaptive immune responses to pathogens. To elucidate the role of IFNIs in host resistance to chlamydial infection in vivo, we compared IFN-alpha/beta receptor knockout (IFNAR(-/-)) and wild-type control mice in susceptibility to Chlamydia trachomatis mouse pneumonitis (Chlamydia muridarum) lung infection. We found that the IFNAR(-/-) mice were significantly more resistant to C. muridarum infection showing less bacterial burden and bodyweight loss, and milder pathological changes. However, IFN-gamma response, which is believed to be critical in host defense against chlamydial infection, was similar between the wild-type and IFNAR(-/-) mice. More importantly, TUNEL analysis showed less macrophage apoptosis in IFNAR(-/-) mice, which was consistent with lower expressions of IFNI-induced apoptotic factors, TRAIL, Daxx, and PKR. Furthermore, depletion of lung macrophages with dichloromethylene diphosphonate-liposome significantly increased the susceptibility of the IFNAR(-/-) mice to C. muridarum, confirming the importance of macrophages. Overall, the data indicate that IFNIs play a promoting role in C. muridarum lung infection, largely through increase of local macrophage apoptosis.

Intranasal inoculation of Chlamydia trachomatis mouse pneumonitis agent induces significant neutrophil infiltration which is not efficient in controlling the infection in mice.

Previous studies have shown that chlamydial infection is accompanied by significant infiltration of neutrophils at the site of infection. However, the role of neutrophils in host defence against chlamydial infection is not clearly understood. Using genetically different inbred mouse strains and CXCR-2 gene knockout (KO) mice, we examined the mechanism for neutrophil recruitment and the role of neutrophils during chlamydial lung infection. Our data showed that C3H mice exhibited significantly higher and more persistent neutrophil infiltration in the lung than did C57BL/6 mice following Chlamydia trachomatis mouse pneumonitis infection. The massive neutrophil infiltration in C3H mice was paralleled by high-level expression of CXCR-2 and its ligands, CXC chemokines (macrophage inflammatory protein 2, cytokine-induced neutrophil attractant (KC) and lipopolysaccharide-induced CXC chemokine), and proinflammatory cytokines (tumour necrosis factor-alpha, interleukin-1 and interleukin-6) in the lung. Although much greater infiltration of neutrophils was observed in C3H mice than in C57BL/6 mice, the former mice had more severe disease and higher in vivo chlamydial growth than the latter. Moreover, CXCR-2 KO mice, which revealed a dramatic reduction in neutrophil activity, showed comparable chlamydial infection to wild-type mice. These results suggest that neutrophils are not efficient for controlling chlamydial lung infection.

Less inhibition of interferon-gamma to organism growth in host cells may contribute to the high susceptibility of C3H mice to Chlamydia trachomatis lung infection.

T-helper-1-like cytokine response and cell-mediated immunity have been shown to be critical in host resistance to Chlamydia trachomatis infection. Using a murine pneumonia model, we compared the susceptibility of C3H/HeN (C3H) and C57BL/6 mice to C. trachomatis mouse pneumonitis (MoPn) infection. C3H mice exhibited significantly higher mortality, greater organism growth and much more severe pathological changes in the lung compared with C57BL/6 mice. However, the pattern of adaptive immune responses including organism-specific delayed-type hypersensitivity, antibody responses and cytokine [interferon-gamma (IFN-gamma), interleukin-12 (IL-12), IL-4, IL-10 and tumour necrosis factor alpha] production by spleen and local draining lymph node cells in these two strains of mice appeared comparable during the process of infection. Interestingly, MoPn growth in the cultured ex vivo macrophages from C3H mice was found to be significantly less inhibited by the exogenous IFN-gamma present in the culture compared to C57BL/6 mice. The lower inhibition of MoPn growth in C3H mice was associated with significantly lower nitric oxide production by the infected macrophages following IFN-gamma stimulation. The data suggest that the cellular events downstream of cytokine production in chlamydia host cells may be important in determining the different susceptibility of hosts to chlamydial infection.

[The clinicopathological features of early renal amyloidosis].

OBJECTIVE: To investigate the clinicopathological manifestations of early renal amyloidosis (AL) and its diagnostic criteria. METHODS: Fifteen cases with early renal amyloidosis admitted from 1994 to 2001 were collected from the hospital, and their clinical and pathological features were reviewed. Of them, the initial diagnoses were not made by depending findings from the light microscopy (LM) and immunofluorescense (IF), but confirmed by electron microscopy (EM) afterwards. Immuno-electron microscopy (IEM) were applied for amyloidosis typing. RESULTS: Most patients of early renal AL were in the middle to old age. Nephrotic syndrome was the most prominent symptoms and signs accompanying with rare microscopic hematuria and hypertension. Most of them had a normal renal function. Pathological examinations of renal biopsies using LM and IF showed mild mesangial proliferation and mild thickening of glomerular basement membrane (GBM). Immunoglobulins and complements were negative or only scanty in certain cases, but in all cases there was a light chain protein deposition homogeously. There were 4 cases of minimal change glomerulopathy, 5 cases of mild mesangial proliferative glomerulonephritis, 5 cases of stage I membranous nephropathy, and 1 case of cast nephropathy diagnosed with LM. The amyloid fibrils (diameter 8 - 10 nm) were randomly distributed in the mesangium, along GBM and at the arteriolar wall under EM. Additionally, Congo red staining was positive. IEM demonstrated that amyloid fibrils labeled with colloid gold was combined with a kind of light chain protein which was confirmed as the light chain type of AL. CONCLUSIONS: The diagnosis of early renal AL was occasionally neglected by depending only findings of LM and LF. However, special amyloid fibrils can be detected using EM. EM observation is an indispensable technique for the diagnosis of early renal AL and the typing of AL may further be determined by using IEM.