Multiparameter spectral CT-based radiomics in predicting the expression of programmed death ligand 1 in non-small-cell lung cancer

AIM

To explore the value of radiomics for predicting the expression of programmed death ligand 1 (PD-L1) in non-small-cell lung cancer (NSCLC) based on multiparameter spectral computed tomography (CT) images.

MATERIALS AND METHODS

A total of 220 patients with NSCLC were enrolled retrospectively and divided into the training (n=176) and testing (n=44) cohorts. The radiomics features were extracted from the conventional CT images, mono-energy 40 keV images, iodine density (ID) maps, Z-effective maps, and electron density maps. The logistic regression (LR) and support vector machine (SVM) algorithms were employed to build models based on radiomics signatures. The prediction abilities were qualified by the area under the curve (AUC) obtained from the receiver operating characteristic (ROC) curve. Internal validation was performed on the independent testing dataset.

RESULTS

The combined model for PD-L1 ≥1%, which consisted of the radiomics score (rad-score; p<0.0001), white blood cell (WBC; p=0.027) counts, and air bronchogram (p=0.003), reached the highest performance with the AUCs of 0.873 and 0.917 in the training and testing dataset, respectively, which was better than the radiomics model with the AUCs of 0.842 and 0.886. The combined model for PD-L1 ≥50%, which consisted of rad-score (p<0.0001) and WBC counts (p=0.027), achieved the highest performance in the training and testing dataset with AUCs of 0.932 and 0.903, respectively, which was better than the radiomics model with AUCs of 0.920 and 0.892, respectively.

CONCLUSION

The radiomics model based on the multiparameter images of spectral CT can predict the expression level of PD-L1 in NSCLC. The combined model can obtain higher prediction efficiency and serves as a promising method for immunotherapy selection.

[Analysis of epidemiological characteristics and risk factors of catheter-associated urinary tract infections in patients with perineal and/or hip burns]

Objective: To explore the epidemiological characteristics and risk factors of catheter-associated urinary tract infections in patients with perineal and/or hip burns. Methods: This study was a retrospective case series study. From January 2018 to December 2022, 260 patients with perineal and/or hip burns and urinary catheters indwelling who met the inclusion criteria were admitted to the Department of Burns and Wound Repair of the Second Affiliated Hospital of Zhejiang University School of Medicine, including 192 males and 68 females, aged 20-93 years. The total incidence of catheter-associated urinary tract infections in patients with perineal and/or hip burns, the detection of pathogenic bacteria, and the resistance of major Gram-negative and Gram-positive bacteria to commonly used antimicrobial drugs in clinic were recorded. According to whether catheter-associated urinary tract infection occurred or not, the patients were divided into infection group (43 cases) and non-infection group (217 cases). The basic conditions including gender, age, total burn area, depth of perineal burn, depth of hip burn, and burn site on admission, complications of diabetes mellitus, inhalation injury, and hypoproteinaemia, invasive operations including tracheotomy and non-perineal/hip debridement/skin transplantation surgery, duration of catheter retention, number of urethral catheterization, and bladder irrigation of patients between the two groups were compared, and the independent risk factors influencing the occurrence of catheter-associated urinary tract infections in patients with perineal and/or hip burns were screened. Results: The total incidence of catheter-associated urinary tract infections in patients with perineal and/or hip burns in this study was 16.5% (43/260). The pathogens detected were predominantly Gram-negative, followed by fungi; the main Gram-negative bacterium was Klebsiella pneumoniae, and the main Gram-positive bacterium was Enterococcus faecalis. The resistance rates of Klebsiella pneumoniae to amoxicillin/clavulanic acid, amitraz, amikacin, ciprofloxacin, ceftriaxone, and levofloxacin were higher than 70.0%, the resistance rates of Klebsiella pneumoniae to cefoxitin, cefoperazone/sulbactam, cefepime, meropenem, imipenem, and piperacillin/tazobactam ranged from 56.3% to 68.8%, and the resistance rates of Klebsiella pneumoniae to ceftazidime and tigecycline were lower than 50.0%. The resistance rates of Enterococcus faecalis to ciprofloxacin and penicillin were both 85.7%, the resistance rates of Enterococcus faecalis to erythromycin, clindamycin, moxifloxacin, and tetracycline ranged from 14.3% to 57.1%, and the resistance rates of Enterococcus faecalis to linezolid, tigecycline, and vancomycin were all 0. The differences were statistically significant between the two groups in terms of gender, status of complication of hypoproteinaemia, depth of perineal burn, status of non-perineal/hip debridement/skin transplantation surgery, status of bladder irrigation, number of urethral catheterization, and duration of catheter retention of patients (with χ2 values of 7.80, 4.85, 10.68, 9.11, and 16.48, respectively, and Z values of -4.88 and -5.42, respectively, P<0.05). There were no statistically significant differences in the age, total burn area, complications of diabetes mellitus and inhalation injury, burn site, depth of hip burns, and status of tracheotomy of patients between the two groups (P>0.05). Multifactorial logistic regression analysis showed that gender, deep partial-thickness perineal burns, non-perineal/hip debridement/skin transplantation surgery, bladder irrigation, and duration of catheter retention were the independent risk factors for catheter-associated urinary tract infections in patients with perineal and/or hip burns (with odds ratios of 2.86, 2.63, 2.79, 2.34, and 1.04, respectively, with 95% confidence intervals of 1.21-6.73, 1.03-6.71, 1.03-7.59, 1.05-5.22, and 1.02-1.06, respectively, P<0.05). Conclusions: The incidence of catheter-associated urinary tract infections is high in patients with perineal and/or hip burns, with Klebsiella pneumoniae as the predominant pathogenic bacteria having a high resistance rate to commonly used antimicrobial drugs in clinic. Gender, deep partial-thickness perineal burns, non-perineal/hip debridement/skin transplantation surgery, bladder irrigation, and duration of catheter retention are the independent risk factors for catheter-associated urinary tract infections in patients with perineal and/or hip burns.

Smilax china L.: A review of its botany, ethnopharmacology, phytochemistry, pharmacological activities, actual and potential applications

ETHNOPHARMACOLOGICAL RELEVANCE

Smilax china L., an extensively used traditional Chinese medicine, is known as Baqia in China. It has been used to treat various inflammatory disorders, particularly pelvic inflammation.

AIM OF THE REVIEW

The present paper aims to provide an up-to-date review at the advancements of the investigations on the ethnopharmacology, phytochemistry, pharmacological effect and actual and potential applications of S. china. Besides, the possible tendency and perspective for future research of this plant are discussed, as well.

MATERIALS AND METHODS

This article uses "Smilax china L." "S. china" as the keyword and collects relevant information on Smilax china L. plants through electronic searches (Elsevier, PubMed, ACS, CNKI, Google Scholar, Baidu Scholar, Web of Science), relevant books, and classic literature about Chinese herb.

RESULTS

134 chemical constituents, among which steroid saponins and flavonoids are the predominant groups, have been isolated and identified from S. china. S. china with its active compounds is possessed of wide-reaching biological activities, including anti-inflammatory, anti-cancer, anti-oxidant, detoxify nicotine, anti-diabetes, anti-obesity, anti-hyperuricaemia, anti-hypertension, promoting skin wound and barrier repair and anti-bacterial activity. Besides, S. china is also applied to other fields, such as food industry and detection technology.

CONCLUSIONS

Based on the review of the existing phytochemical studies on Smilax china L., the structural characterization of Smilax china L. extract can continue to be the focus of future research. Pharmacological studies in vitro and in vivo have demonstrated some of the traditional uses of Smilax china L. extract, while other traditional uses still need to be confirmed by research.

[Current status and research advances on catheter-associated urinary tract infection in burn patients]

Catheter-associated urinary tract infection (CAUTI) is one of the common nosocomial infections in burn patients. It not only extends the length of hospital stay of patients, increases the economic burden on family and society, but also seriously affects the prognosis and quality of life of patients, increases the risk of death of patients. In this paper, the epidemiological characteristics, influencing factors, and prevention measures of CAUTI in burn patients are reviewed to draw high attention of clinical medical staff and to provide some reference for clinical practice.

[Research progress on moderate and deep sedation during wound dressing change in pediatric burn patients]

Moderate and deep sedation can effectively relieve or eliminate the pain and body discomfort during wound dressing change in pediatric burn patients, relieve anxiety, agitation, and even delirium of the children, reduce the metabolic rate of the children, make them in a quiet, comfortable, and cooperative state, which is conducive to the smooth completion of dressing change. This paper summarized the three aspects of moderate and deep sedation in pediatric burn patients, including the overview, main points of implementation, and effects, and further introduced the moderate and deep sedation medication regimens for different routes of administration, as well as the content of evaluation and monitoring. Suggestions on the prevention and management of related complications and the management of moderate and deep sedation implementation procedures were put forward, in order to provide references for the development of moderate and deep sedation for wound dressing change in pediatric burn patients in China.

[Risk considerations of periodontal tissues reconstructions in the strategies of orthodontic treatment]

With the increase of adult patients seeking for orthodontic treatment, the influence of periodontal tissue on orthodontic treatment has gradually become the focus. For patients with periodontitis, it is essential to controlling the severity of periodontitis prior to orthodontic treatment. Periodontal disease can cause additional bone loss and make the orthodontic treatment complicated. Reducing the risk of orthodontic treatment in this situation is our major concern. In addition to periodontitis, orthodontic treatment may also cause gingival recession. On the other hand, the alveolar bone defects such as bone fenestration and bone dehiscence are common in some patients without periodontitis. For these patients, we should take more care of the interrelationship between bone defects and orthodontic treatment. This article briefly demonstrates the risk considerations of periodontal supporting tissue in orthodontic therapy focusing on the influence of periodontitis, gingival recession and alveolar bone fenestration and dehiscence.

[Efficacy of first generation EGFR-TKIs and chemotherapy as first-line therapy in advanced lung adenocarcinoma patients with uncommon EGFR mutations]

Objective: To investigate the clinical effects of first generation epithelial growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) compared with platinum-based chemotherapy as first-line therapy in advanced lung adenocarcinoma patients with uncommon EGFR mutations. Methods: Clinical data of 4 276 patients diagnosed as advanced lung adenocarcinoma (ⅢB/Ⅳ) underwent EGFR gene detection at the Affiliated Cancer Hospital of Zhengzhou University from January 2012 to February 2018 were collected and 99 cases with uncommon EGFR mutations were selected. The clinical pathological features, treatment outcomes, treatment options and prognosis after first-line treatment of the 99 cases were analysed and compared with other patients with common EGFR mutations. Results: The objective response rates of patients with uncommon EGFR mutations receiving EGFR-TKIs or platinum-based chemotherapy were 33.0% and 27.1%, respectively. The disease control rates were 76.5% and 87.5%, respectively. The progression-free survival (PFS) of patients treated with EGFR-TKIs was 7.2 months, significantly superior than 4.9 months of patients receiving chemotherapy (P=0.009). The overall survival of patients treated with EGFR-TKIs was 14.3 months, significantly worse than 20.7 months of patients receiving chemotherapy (P=0.034). Multivariate analysis showed that distant metastases (P=0.001) and smoking history (P=0.013) were independent prognostic factors for OS of lung adenocarcinoma patients with EGFR uncommon mutations. Conclusions: Compared with chemotherapy, the usage of first generation of EGFR-TKIs as first-line therapy can improve the short-term efficacy of advanced lung adenocarcinoma patients with EGFR uncommon mutations. However, platinum-based chemotherapy shows a longer overall survival.

[Association between maternal body height and risk of preterm birth]

Objective: To investigate the association between maternal body height and risk of preterm birth. Methods: A total of 11 311 pregnant women who gave birth of live singletons were recruited from the Healthy Baby Cohort Study in Hubei province, China from September 2012 to October 2014. Finally 11 070 pregnant women were selected as study subjects. Data were collected by using questionnaires, their prenatal care records and medical records. The women were divided into 4 groups according to the quartiles distribution (<158 cm, 158- cm, 160- cm, and >164 cm). Gestational age was estimated according to maternal last menstrual time. Preterm birth was defined as delivering a live singleton infant at 28-37 weeks' gestational age. Logistic regression was used to calculate the odds ratios (OR) and 95% confidence intervals (CI) for the association between body height and preterm birth. Results: Among the 11 070 pregnant women, the incidence of preterm birth was 5.9%. Logistic regression analysis indicated that women in group with body height <158 cm had 46% (OR=1.46, 95%CI: 1.16-1.83) higher risk of giving preterm birth than those in group with body height >164 cm after adjustment for potential confounders. Every 1- cm increase in body height was associated with 3% lower risk of preterm birth (OR=0.97, 95%CI: 0.95-0.99). Conclusion: Shorter body height was a risk factor for preterm birth. It is necessary to strengthen the monitoring in pregnant women with short body height to reduce the risk of preterm birth.

[Analysis of the related factors of attention deficit/hyperactivity disorder and allergic rhinitis in children]

Objective:To investigate the association between symptom of attention deficit/hyperactivity disorder (ADHD) and allergic rhinitis (AR) in children with AR at different sexes and different ages. Method:A total of 439 AR children aged 6 to 12 years were enrolled in this study. Basic information (age, gender, medical history, family history and comorbidities) of children with AR was collected. Results of prick tests on children skin were recorded. (TNSS) and Chinese version of the SNAP-Ⅳ scale, children under the guidance of independent completion of children's quality of life of children with nasal conjunctivitis scale (PRQLQ). According to the results of SNAP-Ⅳ, children were divided into AR with ADHD group ［attention deficit and hyperactivity symptom score (IHS) >1.25］ and AR without ADHD group (IHS≤1.25). The differences between the two groups of children were analyzed using group t-test and χ² test, and the relationship between each parameter and IHS >1.25 was analyzed by binary logistic regression. Result:Using SPSS 22.0 software, among all the included AR children, IHS >1.25 children accounted for 26.4%, IHS >1.25 group AR symptom scores were significantly higher than HIS ≤1.25 groups. Univariate analysis showed that children with age, gender, duration of AR symptoms, skin index and PRQLQ subscales had a correlation with IHS >1.25. After controlling for age and gender, duration of AR symptoms and skin index correlated with IHS >1.25 The estimated OR values are 1.807 (95%CI: 1.350-2.419) and 1.912 (95%CI: 1.320-2.772), respectively. The estimated OR values of PRQLQ subscale and IHS >1.25 were 1.657 (nasal symptom score), 1.324 (eye symptom score), 2.48 (non-eye-nasal symptom score), 1.418 (Behavior problem score) and 2.045 (activity and sleep score). The correlation between IHS>1.25 and the skin index and PRQLQ subscales was mainly found in males with stratification of age and gender, and the association between duration of AR symptoms and HIS >1.25 was statistically significant among all groups reflected. Conclusion:The association between attention deficits and hyperactivity symptoms in AR children was correlated with the severity of AR symptoms, duration, and skin index, and this association was more pronounced in males. In children with AR and ADHD, early management of AR symptoms may improve their ADHD symptoms.

[Analysis on clinical characteristics and prognosis of patients with mitral valve prolapse]

Objective: To evaluate the clinical characteristics and prognosis of patients with mitral valve prolapse (MVP). Methods: We retrospectively analyzed the clinical characteristics and prognosis of 148 MVP patients who underwent mitral valve surgery in Fuwai hospital from January 2012 to December 2015.The patients were divided into mucoid degeneration group (52 cases) and without mucoid degeneration group(19 cases) according to pathological examination of leaflets and chordate. Results: The clinical symptoms of MVP patients included dyspnea (59.5%(88/148)), chest distress and pain (52.7%(78/148)), and palpitations (36.5% (54/148)). Mitral valve repair was performed in 144 cases (97.3%), and mitral valve replacement was performed in 4 cases (2.7%). Posterior leaflet prolapse was the most common form of MVP (68.9%, 102/148). Pathological examination revealed myxomatous degeneration in 73.2% patients (52/71), fibrosis in 8.5% patients (6/71), and fibrinoid necrosis in 8.5% patients (6/71). Patients with mucoid degeneration had less atrial fibrillation before surgery (5.8%(3/52) vs. 42.1%(8/19), P<0.01), smaller preoperative left atrium diameter ((43.2±6.5) mm vs. (48.2±8.9) mm, P<0.05), more posterior leaflet prolapse (94.2%(49/52) vs. 63.2%(12/19), P<0.01), redundant chordae (26.9%(14/52) vs. 0, P<0.05) and leaflet thickening (76.9%(40/52) vs. 52.6%(10/19), P<0.05) when compared with patients without mucoid degeneration.Echocardiography examination at the postoperative follow-up of 39.0(22.3, 57.0) months revealed smaller left atrium diameter((38.5±7.1) mm vs. (45.3±8.3) mm, P<0.01), left ventricular end-diastolic diameter ((48.9±6.2) mm vs. (57.5±7.6) mm, P<0.01), reduced left ventricular ejection fraction ((61.2±7.1)% vs. (65.1±6.2)%, P<0.01) and less moderate or severe mitral regurgitation (1.4%(2/148) vs. 100.0%(148/148), P<0.01) compared with the corresponding preoperative values. Conclusions: Dyspnea is the main symptom, and mucoid degeneration characterized by redundant chordae and leaflet thickening are the main pathological features of MVP patients.The surgical treatment of MVP patients is related with satisfactory outcome results.

[Comparison of two quantitative methods of endobronchial ultrasound real-time elastography for evaluating intrathoracic lymph nodes]

Objective: To compare the clinical value of two quantitative methods in analyzing endobronchial ultrasound real-time elastography (EBUS-RTE) images for evaluating intrathoracic lymph nodes. Methods: From January 2014 to April 2014, EBUS-RTE examination was performed in patients who received EBUS-TBNA examination in Shanghai Chest Hospital. Each intrathoracic lymph node had a selected EBUS-RTE image. Stiff area ratio and mean hue value of region of interest (ROI) in each image were calculated respectively. The final diagnosis of lymph node was based on the pathologic/microbiologic results of EBUS-TBNA, pathologic/microbiologic results of other examinations and clinical following-up. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy were evaluated for distinguishing malignant and benign lesions. Results: Fifty-six patients and 68 lymph nodes were enrolled in this study, of which 35 lymph nodes were malignant and 33 lymph nodes were benign. The stiff area ratio and mean hue value of benign and malignant lesions were 0.32±0.29, 0.62±0.20 and 109.99±28.13, 141.62±17.52, respectively, and statistical differences were found in both of those two methods (t=-5.14, P<0.01; t=-5.53, P<0.01). The area under curves was 0.813, 0.814 in stiff area ratio and mean hue value, respectively. The optimal diagnostic cut-off value of stiff area ratio was 0.48, and the sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 82.86%, 81.82%, 82.86%, 81.82% and 82.35%, respectively. The optimal diagnostic cut-off value of mean hue value was 126.28, and the sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 85.71%, 75.76%, 78.95%, 83.33% and 80.88%, respectively. Conclusion: Both the stiff area ratio and mean hue value methods can be used for analyzing EBUS-RTE images quantitatively, having the value of differentiating benign and malignant intrathoracic lymph nodes, and the stiff area ratio is better than the mean hue value between the two methods.

Geniposide improves insulin production and reduces apoptosis in high glucose-induced glucotoxic insulinoma cells

Our previous work revealed that in the pancreatic β cell line, geniposide modulated ATP production and glucose-stimulated insulin secretion (GSIS) induced by the acute stimulation of high glucose concentration. However, the effects of geniposide on functional impairment and the mass of β-cells exposed to elevated levels of glucose remains unknown. In the present study, impaired GSIS and restrained proliferation were observed in the prolonged culture of insulinoma INS-1 cells with 33mM of glucose (high glucose). Our results indicate that the glucose-induced impairment of insulin release was significantly reverted by the inclusion of 1 or 10μM of geniposide. Moreover, induction of the phosphorylation of AMP-activated protein kinase (AMPK) was observed, which promoted the utilization of nutrient stores for energy production. AMPK phosphorylation was enhanced by an increased number of INS-1 cells, and the increased expression of AMPK downstream target heme oxygenase 1 (HO-1), under high glucose concentration. Furthermore, geniposide protected rat insulinoma cells from apoptosis in high-glucose concentrations. We have shown that these effects were associated with an increased apoptosis-related Bcl-2/BAX protein ratio. In conclusion, geniposide dose dependently improves β-cell function and increases the proliferation of β-cells exposed to prolonged hyperglycemia.

[Atrial fibrillation in patients with obstructive hypertrophic cardiomyopathy: clinical characteristics and risk factors]

Objective: To evaluate the clinical characteristics and risk factors for atrial fibrillation(AF)in patients with obstructive hypertrophic cardiomyopathy(OHCM). Methods: Patients with OHCM hospitalized in Fuwai Hospital from March 2011 to January 2016 were enrolled in the present study. Each patient underwent examinations including transthoracic echocardiography, body surface electrocardiograph or dynamic electrocardiogram (Holter). Cardiac troponin I (cTNI) and N-terminal pro-brain natriuretic peptide (NT-pro-BNP)levels were tested and clinical profiles were collected.The subjects were divided into two groups (the AF group and non-AF group). Risk factors for AF in patients with OHCM were assessed by multivariate logistic regression analysis. Results: A total of 309 patients were evaluated in the study. Among them, 17.5%( 54/309) patients were with AF.Age[(51.2±10.1)years vs (43.1 ± 14.4)years], New York Heart Association class(NYHA class)(2.8±0.5 vs 2.6±0.6), disease duration[6.0(4.0, 10.0)years vs 3.0(1.0, 6.0)years], left atrial (LA) dimension[(45.1±7.0)mm vs(42.6 ± 7.4)mm]and NT-pro-BNP levels[2 007(1 565, 3 199)pmol/L vs 1 509(729, 2 921)pmol/L]in the AF group were significantly higher than those in the non-AF group (all P<0.05). Multivariate logistic regression analysis indicated that advanced age(OR=1.04, 95% CI 1.01-1.08, P<0.01), higher NYHA class(OR=2.00, 95% CI 1.08-3.70, P<0.05)and longer disease duration(OR=1.08, 95% CI 1.01-1.15, P<0.05)were independent risk factors for AF in patients with OHCM, in which advanced age(OR=1.05, 95% CI 1.02-1.09, P<0.01), higher NYHA class(OR=3.39, 95% CI 1.53-7.54, P<0.01), LA dimension(OR=1.06, 95% CI 1.01-1.12, P<0.05)and longer clinical course(OR=1.12, 95% CI 1.04-1.20, P<0.01)were associated with AF in male patients, and advanced age (OR=1.05, 95% CI 1.01-1.09, P<0.05)and longer disease duration(OR=1.14, 95% CI 1.01-1.28, P<0.01)were associated with AF in female patients when stratified by gender. Conclusion: Advanced age , higher NYHA class and longer clinical duration are independent risk factors for AF in OHCM patients.

Combined Anti-CD154/CTLA4Ig Costimulation Blockade-Based Therapy Induces Donor-Specific Tolerance to Vascularized Osteomyocutaneous Allografts

Tolerance induction by means of costimulation blockade has been successfully applied in solid organ transplantation; however, its efficacy in vascularized composite allotransplantation, containing a vascularized bone marrow component and thus a constant source of donor-derived stem cells, remains poorly explored. In this study, osteomyocutaneous allografts (alloOMCs) from Balb/c (H2(d) ) mice were transplanted into C57BL/6 (H2(b) ) recipients. Immunosuppression consisted of 1 mg anti-CD154 on day 0, 0.5 mg CTLA4Ig on day 2 and rapamycin (RPM; 3 mg/kg per day from days 0-7, then every other day for 3 weeks). Long-term allograft survival, donor-specific tolerance and donor-recipient cell trafficking were evaluated. Treatment with costimulation blockade plus RPM resulted in long-term graft survival (>120 days) of alloOMC in 12 of 15 recipients compared with untreated controls (median survival time [MST] ≈10.2 ± 0.8 days), RPM alone (MST ≈33 ± 5.5 days) and costimulation blockade alone (MST ≈45.8 ± 7.1 days). Donor-specific hyporesponsiveness in recipients with viable grafts was demonstrated in vitro. Evidence of donor-specific tolerance was further assessed in vivo by secondary donor-specific skin graft survival and third-party graft rejection. A significant increase of Foxp3(+) regulatory T cells was evident in tolerant animals. Donor cells populated peripheral blood, thymus, and both donor and recipient bone marrow. Consequently, combined anti-CD154/CTLA4Ig costimulation blockade-based therapy induces donor-specific tolerance in a stringent murine alloOMC transplant model.

Combined PCR and Q-RT-PCR technique for detecting chimerism in a non-human Primate vascularized osteomyocutaneous allografts model

Face transplantation and other composite tissue transplantation (CTA) are permissive to transplantation tolerance. The real reason, that composite tissue containing bone achieves transplantation immune tolerance more easily than the composite tissue without the bone is not clear. The chimerism may be the main mechanism in the progress of inducing the transplantation tolerance by CTA. We currently have established a non-human Primate Vascularized Osteomyocutaneous Allografts Model. To test the chimerism which comes from donor after the transplantation, we developed a method which combined reverse transcription polymerase chain reaction (RT-PCR) and real-time quantitative PCR (qRT-PCR) technique using primers specific for Macaca fascicularis sex determination region on the Y chromosome (SRY) gene. With the method, we estimated the level of the chimerism.

Development and characterization of Rift Valley fever virus-like particles

Rift Valley fever (RVF) is an acute, febrile zoonotic disease that is caused by the RVF virus (RVFV) and spread by arthropod vectors. RVF is currently prevalent in Africa and the Arabian Peninsula, and causes substantial economic losses. Furthermore, this disease poses a serious threat to animal and human health in regions worldwide, making it a serious public health concern. However, RVFV vaccines for human use are still unavailable, and hence there is an urgent need for novel efficient vaccines against RVFV. Vaccine preparation techniques have become a crucial factor in developing new vaccines. In the current study, the N and G protein genes of RVFV were inserted into the pFastBacDual baculovirus expression vector downstream of the pP10 and pPH promoters. The resultant recombinant vector, pFastBacDual-S-M, was transfected into Sf9 insect cells by lipofection. The recombinant baculovirus, named rBac-N-G, was retrieved and infected into Sf9 insect cells to generate RVFV virus-like particles (VLPs). Using polyclonal antibodies against RVFV proteins in immunofluorescence and western blot analyses, we positively identified the presence of the RVFV proteins in VLP preparations. Sucrose density gradient centrifugation and transmission electron microscopy revealed that the morphology of the RVFV VLPs was consistent with previous reports of RVFV virions. This study describes a technique for efficient production of RVFV VLPs, and has laid the foundation for future VLP-based RVFV vaccines.

Spontaneous resolution of acute rejection and tolerance induction with IL-2 fusion protein in vascularized composite allotransplantation

Vascularized composite allotransplantation (VCA) has emerged as a treatment option for treating nonlife-threatening conditions. Therefore, in order to make VCA a safe reconstruction option, there is a need to minimize immunosuppression, develop tolerance-inducing strategies and elucidate the mechanisms of VCA rejection and tolerance. In this study we explored the effects of hIL-2/Fc (a long-lasting human IL-2 fusion protein), in combination with antilymphocyte serum (ALS) and short-term cyclosporine A (CsA), on graft survival, regulatory T cell (Treg) proliferation and tolerance induction in a rat hind-limb transplant model. We demonstrate that hIL-2/Fc therapy tips the immune balance, increasing Treg proliferation and suppressing effector T cells, and permits VCA tolerance as demonstrated by long-term allograft survival and donor-antigen acceptance. Moreover, we observe two distinct types of acute rejection (AR), progressive and reversible, within hIL-2/Fc plus ALS and CsA treated recipients. Our study shows differential gene expression profiles of FoxP3 versus GzmB, Prf1 or interferon-γ in these two types of AR, with reversible rejection demonstrating higher Treg to Teff gene expression. This correlation of gene expression profile at the first clinical sign of AR with VCA outcomes can provide the basis for further inquiry into the mechanistic aspects of VCA rejection and future drug targets.

Biologics and donor bone marrow cells for targeted immunomodulation in vascularized composite allotransplantation: a translational trial in swine

INTRODUCTION

Bone marrow (BM) infusion following organ transplantation is a prerequisite for potential donor-antigen-specific tolerance induction. We developed a preclinical swine model to determine the optimal dose of BM cells to achieve microchimerism. Furthermore, induction therapy was optimized by augmenting the BM infusion with biologics in the form of costimulatory blockade: cytotoxic T-lymphocyte antigen 4 immunoglobulin (CTLA4-Ig).

MATERIALS AND METHODS

Yucatan miniature swine (n = 12) underwent total body and thymic irradiation for cytodepletion. Animal groups received 15, 30, or 60 million cells per kilogram of whole unmodified BM. The optimal dose of BM cell infusion (BMT) was then applied to subsequent experiments evaluating the addition of CTLA4lg. Group 1 (control) received no treatment. Group 2 received FK506 only; group 3 received irradiation, BMT, and FK506; group 4 received FK506 and CTLA4-lg.

RESULTS

Microchimerism was established in all animals after BM cell infusion; at postoperative day 9, it was significantly increased for 60 million cells per kilogram (P = .0001). Transplanted animals in group 1 rejected the allograft 5 to 8 days after transplantation. Group 2 rejected the allograft (skin and muscle) 30 to 32 days after transplantation (2 days after cessation of immunosuppression). Group 3 rejected the skin portion of the allograft at 50, 52, and 53 days posttransplant. Remaining allograft components (muscle, bone, nerve, vessel) survived indefinitely. Group 4 animals demonstrated significantly prolonged muscle survival beyond 150 days posttransplant; the skin component survived past 150 days in two of three animals. Skin and muscle histology in all long-term surviving animals were normal.

CONCLUSIONS

BM cell infusion with 60 million cells per kilogram results in stable levels of microchimerism. The addition of costimulatory blockade (CTLA4lg) prolonged allograft skin survival and overall graft survival. Such targeted immunomodulatory protocols might facilitate immune tolerance and eliminate the need for multidrug immunosuppression to maintain graft survival after vascularized composite allotransplantation.

Potential role of high-mobility group box 1 protein in the pathogenesis of influenza H5N1 virus infection

During influenza A virus (IAV) (H5N1) infection, the levels of inflammatory cytokines are markedly elevated in the lungs of infected hosts. One of them, high-mobility group box 1 protein (HMGB1) functions in regulation of cellular transcription and activation of proinflammatory responses, but little is known about its role in viral infection. In this study, we attempted to address this question. Using an IAV (H5N1) - mouse model, lung tissues were analyzed for virus titer, expression of HMGB1 and other inflammatory cytokines and histopathological changes. Moreover, the effect of administration of HMGB1-specific antibody to the infected mice on these parameters was investigated. The results showed that the HMGB1 expression was induced on days 3-7 post infection (p.i.) and primarily localized to epithelial cells of alveoli and bronchioles. The HMGB1-specific antibody reduced the levels of inflammatory cytokines and chemokines and the survival rate, but did not influence the virus titer. Summing up, these data suggest that HMGB1 contributes to the pathogenesis of IAV (H5N1) infection in mice by inducing extensive inflammatory responses and severe pneumonia.

Phytosterols elevation in bamboo shoot residue through laboratorial scale solid-state fermentation using isolated Aspergillus niger CTBU

Aspergillus niger CTBU isolated from local decayed bamboo shoot residue was employed to solid-state fermentation (SSF) of bamboo shoot residue to elevate the content of phytosterols. Strain acclimatization was carried out under the fermentation condition using bamboo shoot as substrate for fermentation performance improvement. The optimal fermentation temperature and nitrogen level were investigated using acclimatized strain, and SSF was carried out in a 500-ml Erlenmeyer flask feeding 300-mg bamboo shoot residue chips under the optimal condition (33 °C and feeding 4 % urea), and 1,186 mg (100 g)(-1) of total phytosterol was attained after 5-day fermentation, in comparison, only 523 mg (100 g)(-1) of phytosterol was assayed in fresh shoots residue. HPLC analysis of the main composition of total phytosterols displays that the types of phytosterols and composition ratio of main sterols keep steady. This laboratorial scale SSF unit could be scaled up for raw phytosterols production from discarded bamboo shoot residue and could reduce its cost.

Vascularized osteomyocutaneous allografts are permissive to tolerance by induction-based immunomodulatory therapy

Vascularized composite allografts (VCAs) are unique among transplanted organs in that they are composed of multiple tissues with disparate antigenic and immunologic properties. As the predominant indications for VCAs are non-life-threatening conditions, there is an immediate need to develop tolerance induction strategies and to elucidate the mechanisms of VCA rejection and tolerance using VCA-specific animal models. In this study, we explore the effects of in vitro induced donor antigen-specific CD4(-) CD8(-) double negative (DN) Treg-based therapy, in a fully MHC mismatched mouse VCA such as a vascularized osteomyocutaneous as compared to a non-VCA such as a full thickness skin (FTS) transplantation model to elucidate the unique features of VCA rejection and tolerance. We demonstrate that combined therapy with antigen-induced CD4 derived DN Tregs and a short course of anti-lymphocyte serum, rapamycin and IL-2/Fc fusion protein results in donor-specific tolerance to VCA, but not FTS allografts. Macrochimerism was detected in VCA but not FTS allograft recipients up to >60 days after transplantation. Moreover, a significant increase of CD4(+) Foxp3(+) Tregs was found in the peripheral blood of tolerant VCA recipients. These data suggest that VCA are permissive to tolerance induced by DN Treg-based induction therapy.

Adoptive cell therapy using antigen-specific CD4⁻CD8⁻T regulatory cells to prevent autoimmune diabetes and promote islet allograft survival in NOD mice

AIMS/HYPOTHESIS

A new differentiation pathway for CD4(-)CD8(-) (DN) T cells has recently been identified that exhibits the potent function of peripheral converted DN T cells in suppressing immune responses and provides the potential to treat autoimmune diseases. The aim of this study was to determine if the DN T cells converted from CD4(+) T cells of NOD mice retain the antigen-specific regulatory capacity and prevent autoimmune diabetes in vivo. We also sought to determine if the combination of DN T cells with rapamycin promotes islet allograft survival in autoimmune diabetic NOD recipients.

METHODS

NOD CD4(+) T cells were converted to DN T cells in an in vitro mixed-lymphocyte reaction, with or without GAD65 peptide, as previously reported. The antigen-specific DN T cells were adoptively transferred to NOD/SCID mice, new-onset diabetic NOD mice or islet-allograft-recipient NOD mice as the part of cell-based therapy. The development of diabetes and allograft survival was assessed by monitoring blood glucose levels.

RESULTS

NOD CD4(+) T cells were converted in vitro to DN T cells at a rate of 50% and expressed unique cell features. The DN T cells from NOD donors blocked autoimmunity and prevented diabetes in NOD models, and these effects were even greater for GAD65-peptide-primed DN T cells. DN T cells acted in conjunction with rapamycin to suppress alloantigen-triggered T cell proliferation, promoted apoptosis and prolonged islet allograft survival in NOD recipients.

CONCLUSIONS/INTERPRETATION

Administration of the islet beta cell antigen-specific DN T cells can prevent the development of autoimmune diabetes and promote islet allograft survival in NOD mice.

A foot drop correcting FES envelope design method using tibialis anterior EMG during healthy gait with a new walking speed control strategy

Restoring walking functions will greatly improve the foot-drop patients' life quality. In this work, we sampled 10 healthy subjects' gait data when walking in 4 different stride frequency overground and developed a dynamic Functional Electrical Stimulation (dFES) system for foot-drop patients' walk training, using the processed tibialis anterior (TA) muscle EMG signal. The data sampled under the new strategy can be used by FES system directly. And the dFES system can provide dynamic Pulse Width Modulation (PWM) FES serial according to the healthy subjects' TA EMG intensity features.

New insights into mechanisms of spontaneous liver transplant tolerance: the role of Foxp3-expressing CD25+CD4+ regulatory T cells

Liver allografts in mice are accepted across MHC barriers without requirement for immunosuppressive therapy. The mechanisms underlying this phenomenon remain largely undefined. In this study, we investigated the role of Foxp3-expressing CD25(+)CD4(+) regulatory T cells (Treg) in the induction of murine liver transplant tolerance. Foxp3(+)CD25(+)CD4(+) T cells were increased in liver grafts and recipient spleens from day 5 to day 100 posttransplantation, associated with enhanced CTLA4 and TGF-beta expression and IL-4 production. Depletion of recipient CD25(+)CD4(+) T cells using anti-CD25 mAb (250 microg/day) induced acute liver allograft rejection. This was associated with a decreased ratio of Foxp3(+) Treg: T effector cells, decreased IL-4 and elevated IL-10 and IL-2 production by graft-infiltrating T cells, and reduced apoptotic activity of graft-infiltrating CD4(+) and CD8(+) T cells in anti-CD25-mAb-treated recipients. Thus, the data suggest that Foxp3(+)CD25(+)CD4(+)Treg are involved in spontaneous acceptance of liver allografts in mice. The ratio of Treg to T effector cells appears to determine liver transplant outcome. CTLA4, IL-4, TGF-beta and apoptosis of graft-infiltrating T cells are also associated with liver transplant tolerance and may contribute, at least in part, to the mechanisms of Treg-mediated immune regulation in this model.

Locally produced survival cytokines IL-15 and IL-7 may be associated to the predominance of CD8+ T cells at heart lesions of human chronic Chagas disease cardiomyopathy

Human chronic Chagas disease cardiomyopathy (CCC) is an inflammatory-dilated cardiomyopathy occurring years after infection by the protozoan Trypanosoma cruzi. The heart inflammatory infiltrate in CCC shows a 2:1 predominance of CD8(+) in relation to CD4(+) T cells, with a typical Th1-type cytokine profile. However, in vitro expansion of infiltrating T cells from heart biopsy-derived fragments with interleukin-2 (IL-2) and phytohaemagglutinin leads to the outgrowth of CD4(+) over CD8(+) T cells. We hypothesized that survival cytokines, such as IL-2, IL-7 and IL-15 might be differentially involved in the growth and maintenance of heart-infiltrating and peripheral CD8(+) T cells from CCC patients. We found that IL-7 and IL-15 were superior to IL-2 in the expansion and viability of CD8(+) T cells from both PBMC and heart-infiltrating T-cell lines from CCC patients, and the combination of the three cytokines showed synergic effects. Heart-infiltrating CD8(+) T cells showed higher expression of both IL-15R alpha and gamma(c) chain than CD4(+) T cells, which may explain the improvement of CD8(+) T-cell growth in the presence of IL-2 + IL-7 + IL-15. Immunohistochemical identification of IL-15 and the higher mRNA expression of IL-15R alpha, IL-7 and gamma(c) chain in CCC heart tissues compared with control individuals indicate in situ production of survival cytokines and their receptors in CCC hearts. Together, our results suggest that local production of IL-7 and IL-15 may be associated with the maintenance and predominance of CD8(+) T cells, the cells effecting tissue damage in CCC hearts.

Effects of cyclosporine on transplant tolerance: the role of IL-2

Allograft(dagger) transplant outcome, rejection or tolerance, depends upon striking a balance between the pertinent cytopathic and regulatory T cells. The drug cyclosporine is a widely used immunosuppressive agent among transplant recipients. Previous studies have demonstrated that cyclosporine blocks apoptosis of activated T cells and the ability of costimulation blockade based regimens to create peripheral transplant tolerance. We now test the hypothesis that the mechanism by which cyclosporine blocks tolerance induction is IL-2 dependent, and linked to a detrimental effect upon T(reg) function. Our study demonstrates that cyclosporine blocks IL-2 gene expression and activation induced cell death (AICD) of alloreactive T effector cells. We also show that cyclosporine abolishes the beneficial effects of a donor specific transfusion (DST) plus anti-CD154 monoclonal antibody (alpha CD154) regimen on enhanced T(regs) function and allograft tolerance induction. Interestingly, provision of IL-2/Fc, a long-lived form of IL-2, completely reverses the detrimental effects of this adjunctive cyclosporine treatment on AICD of alloreactive T effectors, T(regs) function and tolerance induction. Furthermore, in a MHC mismatched islet allograft model, the combination of cyclosporine with IL-2/Fc permitted long-term allograft survival and induced alloantigen specific allograft tolerance. The combination of IL-2/Fc and cyclosporine treatment may provide a new clinical strategy to promote transplant tolerance.

The role of Foxp3+ regulatory T cells in liver transplant tolerance

The liver has long been considered a tolerogenic organ that favors the induction of peripheral tolerance. The mechanisms underlying liver tolerogenicity remain largely undefined. In this study, we characterized Foxp3-expressing CD4+ CD25+ regulatory T cells (Treg) in liver allograft recipients and examined the role of Treg in inherent liver tolerogenicity by employing the mouse spontaneous liver transplant tolerance model. Orthotopic liver transplantation was performed from C57BL/10 (H2b) to C3H/HeJ (H2k) mice. The percentage of CD4+ CD25+ Treg was expanded in the liver grafts and recipient spleens from day 5 up to day 100 posttransplantation, associated with high intracellular Foxp3 and CTLA4 expression. Immunohistochemistry further demonstrated significant numbers of Foxp3+ cells in the liver grafts and recipient spleens and increased transforming growth factor beta expression in the recipient spleens throughout the time courses. Adoptive transfer of spleen cells from the long-term liver allograft survivors significantly prolonged donor heart graft survival. Depletion of recipient CD4+ CD25+ Treg using anti-CD25 monoclonal antibody (250 microg/d) induced acute liver allograft rejection, associated with elevated anti-donor T-cell proliferative responses, CTL and natural killer activities, enhanced interleukin (IL)-2, interferon-gamma, IL-10, and decreased IL-4 production, and decreased T-cell apoptotic activity in anti-CD25-treated recipients. Moreover, CTLA4 blockade by anti-CTLA4 monoclonal antibody administration exacerbated liver graft rejection when combined with anti-CD25 monoclonal antibody. Thus, Foxp3+ CD4+ CD25+ Treg appear to underpin spontaneous acceptance of major histocompatability complex- mismatched liver allografts in mice. CTLA4, IL-4, and apoptosis of alloreactive T cells appear to contribute to the function of Treg and regulation of graft outcome.

Anti-CD25 mAb Administration Prevents Spontaneous Liver Transplant Tolerance

Liver allografts are accepted spontaneously in all mouse strain combinations without immunosuppressive therapy. The mechanisms underlying this phenomenon remain largely undefined. In this study, we examined the effect of CD4+ CD25+ T regulatory cells (Treg) on the induction of mouse liver transplant tolerance. Orthotopic liver transplantation was performed from B10 (H2b) to C3H (H2k) mice. Depleting rat anti-mouse CD25 mAb (PC61) was given to the donors or recipients (250 microg/d IP) pretransplant or to the recipients postoperatively. At day 5 posttransplantation, both effector T cells (mainly CD8) and CD4+ CD25+ Treg were increased in the liver allografts and host spleens compared to naïve mice. Anti-CD25 mAb administration, either pretransplantation or posttransplantation, reduced the ratio of CD4+ CD25+ Treg to the CD3 T cells of liver grafts and recipient spleens and induced liver allograft acute rejection compared to IgG treatment. Anti-CD25 mAb administration elevated anti-donor T-cell proliferative responses and CTL and NK activities of graft infiltrates and host splenocytes; reduced CTLA4, Foxp3, and IDO mRNA levels; increased IL-10 and IFN-gamma; and decreased IL-4 mRNA levels in the livers or host spleens. The number of apoptotic T cells was reduced significantly in the liver grafts and treated host spleens. Therefore, anti-CD25 mAb administration changed the balance of CD4+ CD25+ Treg to activated T cells of liver graft recipients, preventing liver transplant tolerance. This was associated with enhanced anti-donor immune reactivity, downregulated Treg gene expression, and reduced T cell apoptosis in the grafts and host spleens.

Intragraft activation of genes encoding cytotoxic T lymphocyte effector molecules precedes the histological evidence of rejection in human cardiac transplantation

BACKGROUND

The purpose of the present study was to investigate transcripts of perforin, granzyme B, and Fas ligand (FasL) in heart transplants undergoing rejection.

METHODS

Quantitative reverse transcriptase-polymerase chain reaction was applied for mRNA detection in 29 endomyocardial biopsy specimens from 11 cardiac allograft recipients.

RESULTS

The mRNA levels of granzyme B, perforin, and FasL were higher (P<0.05) in biopsy specimens with rejection than in biopsy specimens without rejection (granzyme B, 0.53 vs. 0.09; perforin, 0.34 vs. 0; FasL, 0.57 vs. 0.36). In prerejection biopsy specimens, granzyme B and FasL levels were significantly higher than in biopsy specimens without rejection. Any two of the three transcripts were increased in 100% of prerejection, in 92% of rejection, and in 36% of no rejection biopsy specimens (P<0.04).

CONCLUSIONS

The assessment of intragraft levels of cytotoxic T lymphocyte effector molecule mRNA represents a valuable tool in the monitoring of cardiac allograft rejection, especially considering the predictive value for warning of impending acute rejection.

Inhibitory effect of jujuboside A on penicillin sodium induced hyperactivity in rat hippocampal CA1 area in vitro

AIM

To study the effect of jujuboside A (JuA), one constituent of Chinese herbal medicine Ziziphus jujuba Mill Var spinosa (Bunge) Hu,on the penicillin sodium induced hyperactivity in rat CA1 neurons in vitro.

METHODS

Hippocampal slices were obtained from the Sprague-Dawley rat brain and populational signals were measured from CA1 neurons of hippocampal slices using the extracellular recording technique.

RESULTS

Penicillin sodium of 500, 1000, and 2000 kU/L were found to excite hippocampal CA1 neurons in a concentration-dependent manner in vitro. This excitatory effect of penicillin sodium could be inhibited by phenobarbital sodium of 0.02 - 0.05 g/L and JuA of 0.05 - 0.10 g/L.

CONCLUSION

A high dose of JuA can inhibit the hyperactivity of hippocampal CA1 area induced by penicillin sodium. The inhibition of the amplitude of the first population spike (PS) and the latency of PS are more pronounced than the slope of the field excitatory post-synaptic potential.

Critical role of Kupffer cell-derived IL-10 for host defense in septic peritonitis

Intra-abdominal infection in patients following major visceral surgery is associated with high mortality. Using a macrophage depletion technique, we demonstrate that in murine septic peritonitis, Kupffer cells are a major source of systemic IL-10 levels. Kupffer cell-depleted mice were highly susceptible to the lethal effects of septic peritonitis and exhibited an increased bacterial load. Kupffer cell-depleted mice were protected by the administration of an IL-10-Fc fusion protein. Loss of Kupffer cell-derived IL-10 was associated with a weak increase in serum IL-12 levels, whereas TNF, IL-1alpha, and IL-18 levels were not significantly elevated, suggesting that the loss of Kupffer cell-derived IL-10 did not result in a toxic cytokine release syndrome. Instead, loss of Kupffer cell-derived IL-10 was associated with a reduced splenocyte production of IFN-gamma that is required for immune protection in murine septic peritonitis. Therefore, the results suggest that the protective function of IL-10 in septic peritonitis may not be restricted to the anti-inflammatory activities of IL-10.

[Hippocampal slice - a model in vitro for screening antiepileptic drugs]

AIM

To establish a model in vitro for screening antiepileptic drugs.

METHODS

Perfusing guinea pig hippocampal slice with penicillin offers a stable epileptiform discharge which was tested by two commonly clinically used antiepileptic drugs, phenytoin sodium and phenobarbital sodium at different concentration.

RESULTS

The experimental result showed that penicillin induced epileptiform discharge in the hippocampal slice and two antiepileptic drugs, phenytoin sodium and phenobarbital sodium inhibition of this discharge induced by penicillin.

CONCLUSION

This electrophysiological model has the advantage of simplicity, flexibility and ease of quantitation and has potential value for screen antiepileptic drugs and epilepsy research.

An IL-2/Ig fusion protein influences CD4+ T lymphocytes in naive and simian immunodeficiency virus-infected Rhesus monkeys

The T cell-stimulatory cytokine interleukin 2 (IL-2) is being evaluated as a therapeutic in the clinical settings of HIV infection and cancer. However, the clinical utility of IL-2 may be mitigated by its short in vivo half-life, toxic effects, and high production costs. We show here that an IL-2/Ig fusion protein possesses IL-2 immunostimulatory activity in vitro and a long in vivo half-life. IL-2/Ig treatment of healthy rhesus monkeys induced significant increases in CD4(+) T lymphocyte counts and expression of CD25 by these cells. Short courses of IL-2/Ig treatment of simian immunodeficiency virus (SIV)-infected rhesus monkeys in conjunction with antiretroviral drugs resulted in increased CD25 expression on T lymphocytes, and transient increases in CD4(+) T lymphocyte counts. Plasma viremia did not increase in these treated animals. Treatment of healthy or SIV-infected rhesus monkeys with a plasmid encoding the IL-2/Ig protein did not affect CD4(+) T lymphocytes. These results demonstrate that IL-2/Ig has potential utility as an immunostimulatory therapeutic.

Uncoupling protein-2 negatively regulates insulin secretion and is a major link between obesity, beta cell dysfunction, and type 2 diabetes

beta cells sense glucose through its metabolism and the resulting increase in ATP, which subsequently stimulates insulin secretion. Uncoupling protein-2 (UCP2) mediates mitochondrial proton leak, decreasing ATP production. In the present study, we assessed UCP2's role in regulating insulin secretion. UCP2-deficient mice had higher islet ATP levels and increased glucose-stimulated insulin secretion, establishing that UCP2 negatively regulates insulin secretion. Of pathophysiologic significance, UCP2 was markedly upregulated in islets of ob/ob mice, a model of obesity-induced diabetes. Importantly, ob/ob mice lacking UCP2 had restored first-phase insulin secretion, increased serum insulin levels, and greatly decreased levels of glycemia. These results establish UCP2 as a key component of beta cell glucose sensing, and as a critical link between obesity, beta cell dysfunction, and type 2 diabetes.

Building international partnerships

Health is a global concern. Although nursing is a global profession, most schools of nursing concentrate on teaching health exclusively within the context of their own nation. Sister-school partnerships that cross national boundaries are one way of extending the learning opportunities of faculties and students. An example of a 5-year partnership is described and analysed.

ADJUNCTIVE RAPAMYCIN AND CsA TREATMENT INHIBITS MONOCYTE/MACROPHAGE ASSOCIATED CYTOKINES/CHEMOKINES IN SENSITIZED CARDIAC GRAFT RECIPIENTS1

BACKGROUND

Although treatment of LEW rats with Rapamycin (RPM) prolongs the survival of LBNF1 cardiac allografts to ca. 50 days, it fails to prevent late activation of macrophage/monocyte-associated chemokines.

METHODS

A 7-day course with RPM or CsA was introduced at 1-week posttransplant in RPM-pretreated hosts. At day 35, intragraft mRNA expression of IL-2, IFN-gamma, TGF-beta, IL-12 (p40), MCP-1, and RANTES was evaluated.

RESULTS

RPM as a sequential treatment markedly inhibited mRNA levels coding for IL-2/IFN-gamma, and MCP-1. However, RPM monotherapy failed to prevent the expression of IL-12 (p40) and RANTES. Adjunctive treatment with CsA markedly depressed IL-12 (p40) and RANTES, and to a lesser extent MCP-1 mRNA, as compared with RPM-treated groups. Significant increase of TGF-beta mRNA expression was revealed after sequential RPM and adjunctive CsA treatment.

CONCLUSIONS

A combination of RPM and CsA is more effective in restraining mRNA expression than RPM alone; however, either therapy is associated with TGF-beta hyperexpression.

Targeting signal 1 through CD45RB synergizes with CD40 ligand blockade and promotes long term engraftment and tolerance in stringent transplant models

The induction and maintenance of allograft tolerance is a daunting challenge. Although combined blockade of CD28 and CD40 ligand (CD40L)-costimulatory pathways prevents allograft rejection in some murine models, this strategy is unable to sustain engraftment in the most immunogenic allograft and strain combinations. By targeting T cell activation signals 1 and 2 with the novel combination of anti-CD45RB and anti-CD40L, we now demonstrate potent enhancement of engraftment in C57BL/6 recipients that are relatively resistant to costimulatory blockade. This combination significantly augments the induction of tolerance to islet allografts and dramatically prolongs primary skin allograft survival. Compared with either agent alone, anti-CD45RB plus anti-CD40L inhibits periislet infiltration by CD8 cells, B cells, and monocytes; inhibits Th1 cytokines; and increases Th2 cytokine expression within the graft. These data indicate that interference with activation signals one and two may provide synergy essential for prolonged engraftment in situations where costimulatory blockade is only partially effective.

Interleukin-2 and interferon-gamma double knockout mice reject heterotopic cardiac allografts

BACKGROUND

Several studies suggest that MHC-mismatched allografts reject with a Th1 or Th2 immune response, but these models all have low-level expression of the Th1 cytokines interleukin (IL)-2 and interferon-gamma (IFN-gamma).

METHODS

We interbred mice with single targeted gene disruptions for IL-2 and IFN-gamma to establish IL-2 + IFN-gamma double knockout (DKO) mice. Heterotopic cardiac allografts from DBA/2j (H2d) donors were transplanted WT, IL-2 knockout (KO), IFN-gamma KO, and DKO recipients (C57BL/6x129; H2b). Cytokine transcripts from allografts and DKO splenocytes were analyzed by reverse transcription polymerase chain reaction.

RESULTS

DKO mice had a cytokine profile and IgG1/ IgG2a isotype ratio characteristic of Th2 deviation. DKO recipients rejected heterotopic cardiac allografts faster than IL-2 KO mice, but significantly slower than WT and IFN-gamma KO mice (P<0.01). Analysis of the rejecting DKO recipients showed intragraft Th2 cytokine expression.

CONCLUSION

The combined absence of IL-2 and IFN-gamma in the setting of Th2 deviation does not prevent allograft rejection.

[An computerized fundus atlas system]

This paper presented an computerized fundus atlas system for WINDOWS. The classical normal and abnormal fundus photoes were digitalized and saved in real color image format. The graphics technology was used to label the area and the feature of the abnormal section with WINDOWS atom functions. When these functions run, the graphics and the texts, which label the area of the selected section and describe their features, were displayed in a carton mode background funds image.

Heritable susceptibility for colitis in mice induced by IL-10 deficiency

Severity of inflammatory bowel disease in IL-10 gene-targeted mice is in part determined by genetic background. In the current study, a targeted IL-10 gene was transferred into the C3H/HeJBir substrain, known to exhibit high T-cell and B-cell responses to enteric flora, and to be highly sensitive to colitigenic stress. IL-10-deficient C3H/HeJBir mice developed early onset colitis in contrast to IL-10-deficient C57BL/6J congenic mice. Histopathologic analysis of disease in C3H/HeJBir.Il10-/- and C57BL/6J.Il10-/- mice showed significant differences at all ages studied. Hybrids of these congenic strains (F1.Il10-/-) were produced to study the mode of inheritance as well as subphenotypes that correlated with histopathology. Lesions in F1 mice were intermediate between parental strains. C3H-contributed subphenotypes that correlated best with histopathology were peripheral blood granulocyte percentage, serum amyloid A concentration, spleen weight/body weight ratio, and mesenteric lymph node weight/ body weight ratio. Neither enhanced humoral immunity (secretory IgA, anti-Escherichia coli cellular membrane Ig) characteristic of C3H/HeJBir, nor T-cell percentages in peripheral blood correlated as well. This study represents a necessary step in elucidating murine genetic modifiers controlling colitis sensitivity.

Control of viremia and prevention of clinical AIDS in rhesus monkeys by cytokine-augmented DNA vaccination

With accumulating evidence indicating the importance of cytotoxic T lymphocytes (CTLs) in containing human immunodeficiency virus-1 (HIV-1) replication in infected individuals, strategies are being pursued to elicit virus-specific CTLs with prototype HIV-1 vaccines. Here, we report the protective efficacy of vaccine-elicited immune responses against a pathogenic SHIV-89.6P challenge in rhesus monkeys. Immune responses were elicited by DNA vaccines expressing SIVmac239 Gag and HIV-1 89.6P Env, augmented by the administration of the purified fusion protein IL-2/Ig, consisting of interleukin-2 (IL-2) and the Fc portion of immunoglobulin G (IgG), or a plasmid encoding IL-2/Ig. After SHIV-89.6P infection, sham-vaccinated monkeys developed weak CTL responses, rapid loss of CD4+ T cells, no virus-specific CD4+ T cell responses, high setpoint viral loads, significant clinical disease progression, and death in half of the animals by day 140 after challenge. In contrast, all monkeys that received the DNA vaccines augmented with IL-2/Ig were infected, but demonstrated potent secondary CTL responses, stable CD4+ T cell counts, preserved virus-specific CD4+ T cell responses, low to undetectable setpoint viral loads, and no evidence of clinical disease or mortality by day 140 after challenge.

Increased nuclear factor-kappaB and angiotensinogen gene expression in posttransplant recurrent focal segmental glomerulosclerosis

In an attempt to identify potential markers of steroid-resistance in focal segmental glomerulosclerosis (FSGS) we evaluated intra-graft gene expression of IkappaBalpha, nuclear factor-kappaB (NF-kappaB), and angiotensinogen in 60 biopsies from 27 pediatric renal transplant recipients. Intra-graft NF-kappaB expression was significantly elevated in recurrent FSGS (R-FSGS) (218.3 + 55.6 ag/fg versus NON-FSGS 121.1 + 19.9, P=0.04) but not in acute rejection. NF-kappaB:IkappaBalpha ratios were higher in cadaveric donor versus living related donor recipients (15.7 + 2.8 vs. 8.8 + 1.3, respectively, P=0.015), and in African-American versus Caucasian recipients (15.6 + 2.9 vs. 9.1 + 1.3, respectively, P=0.03). Intra-graft angiotensinogen gene expression was significantly elevated in R-FSGS (30.5 + 8.8 ag/fg R-FSGS vs. 16.0 + 4.7 NON-FSGS, P=0.009). We conclude that increased NF-kappaB and angiotensinogen gene expression are associated with R-FSGS. Increased NF-kappaB:IkappaBalpha ratios are associated with cadaveric donor recipients and African-American race.

Augmentation of immune responses to HIV-1 and simian immunodeficiency virus DNA vaccines by IL-2/Ig plasmid administration in rhesus monkeys

The potential utility of plasmid DNA as an HIV-1 vaccination modality currently is an area of active investigation. However, recent studies have raised doubts as to whether plasmid DNA alone will elicit immune responses of sufficient magnitude to protect against pathogenic AIDS virus challenges. We therefore investigated whether DNA vaccine-elicited immune responses in rhesus monkeys could be augmented by using either an IL-2/Ig fusion protein or a plasmid expressing IL-2/Ig. Sixteen monkeys, divided into four experimental groups, were immunized with (i) sham plasmid, (ii) HIV-1 Env 89.6P and simian immunodeficiency virus mac239 Gag DNA vaccines alone, (iii) these DNA vaccines and IL-2/Ig protein, or (iv) these DNA vaccines and IL-2/Ig plasmid. The administration of both IL-2/Ig protein and IL-2/Ig plasmid induced a significant and sustained in vivo activation of peripheral T cells in the vaccinated monkeys. The monkeys that received IL-2/Ig plasmid generated 30-fold higher Env-specific antibody titers and 5-fold higher Gag-specific, tetramer-positive CD8+ T cell levels than the monkeys receiving the DNA vaccines alone. IL-2/Ig protein also augmented the vaccine-elicited immune responses, but less effectively than IL-2/Ig plasmid. Augmentation of the immune responses by IL-2/Ig was evident after the primary immunization and increased with subsequent boost immunizations. These results demonstrate that the administration of IL-2/Ig plasmid can substantially augment vaccine-elicited humoral and cellular immune responses in higher primates.

Blocking the common gamma-chain of cytokine receptors induces T cell apoptosis and long-term islet allograft survival

The common gammac-chain is an essential signaling component shared by all known T cell growth factor (TCGF) receptors (i.e., IL-2, IL-4, IL-7, IL-9, and IL-15). In the present study, we have studied the effect of gammac-chain blockade on T cell activation and allograft rejection. Treatment of B6AF1 (H-2b/d.k) recipient mice with anti-gammac mAbs induced long-term survival of DBA/2 (H-2d) islet allografts (>150 days, n = 8), whereas control Ab-treated mice rejected the islet allografts within 17 days (n = 6). The state of engraftment induced by the anti-gammac mAbs was remarkably stable, as recipient mice bearing the primary islet allografts accepted a second DBA/2 islet allograft without further immunosuppression and systemic administration of high doses of IL-2Ig fusion protein failed to provoke rejection. Blocking the gammac-chain inhibited T cell proliferation and induced T cell apoptosis by repressing expression of Bcl-2. Our data suggest that one means of inducing T cell apoptosis and stable allograft survival can be achieved via gammac-chain blockade.

IL-10/Fc inhibits macrophage function and prolongs pancreatic islet xenograft survival

BACKGROUND

Xenograft rejection is a complex response in which macrophages and other effector cells are activated by CD4+ T cells. Initiation and regulation of this response is in part mediated by cytokines. In this study we test the hypothesis that xenograft destruction is an interleukin- (IL) 10 responsive, macrophage-mediated event.

METHODS

To study the effect of the systemic administration of IL-10 on pancreatic islet xenograft rejection, a fusion protein of IL-10/Fc was used. This immunoligand possesses the bioavailability of IL-10 and the long circulating t1/2 in vivo, characteristic of Ig. Wistar rat islets were transplanted into C57BL6 mice. IL-10/Fc was administered either immediately before transplantation or in the posttransplant period.

RESULTS

Both therapeutic protocols prolonged xenograft survival. Macrophage effector function was reduced in IL-10/Fc-treated mice, with a reduced macrophage infiltrate, reduced IL-12 and tumor necrosis factor-alpha gene expression and reduced serum NO2- levels. Although the number of T cells infiltrating islet grafts was not reduced, T cell effector function was inhibited in IL-10/Fc-treated animals with reduced interferon-gamma and IL-4 gene expression, reduced anti-donor cytotoxicity by recipient splenocytes and reduced anti-donor IgG1 antibody production. Ultimate rejection of the xenografts appears to be mediated by a CD4+ T cell dependent mechanism probably as a result of inadequate inhibition of IL-12 production by macrophages.

CONCLUSION

IL-10/Fc prolonged rat pancreatic islet xenograft survival by inhibiting macrophage mediated immune responses. The effectiveness of this agent when administered pretransplant suggests it may have a role as an induction agent with potential clinical application.

Requirement for T-cell apoptosis in the induction of peripheral transplantation tolerance

The mechanisms of allograft tolerance have been classified as deletion, anergy, ignorance and suppression/regulation. Deletion has been implicated in central tolerance, whereas peripheral tolerance has generally been ascribed to clonal anergy and/or active immunoregulatory states. Here, we used two distinct systems to assess the requirement for T-cell deletion in peripheral tolerance induction. In mice transgenic for Bcl-xL, T cells were resistant to passive cell death through cytokine withdrawal, whereas T cells from interleukin-2-deficient mice did not undergo activation-induced cell death. Using either agents that block co-stimulatory pathways or the immunosuppressive drug rapamycin, which we have shown here blocks the proliferative component of interleukin-2 signaling but does not inhibit priming for activation-induced cell death, we found that mice with defective passive or active T-cell apoptotic pathways were resistant to induction of transplantation tolerance. Thus, deletion of activated T cells through activation-induced cell death or growth factor withdrawal seems necessary to achieve peripheral tolerance across major histocompatibility complex barriers.