Cpd-A1 alleviates acute kidney injury by inhibiting ferroptosis

Acute kidney injury (AKI) is defined as sudden loss of renal function characterized by increased serum creatinine levels and reduced urinary output with a duration of 7 days. Ferroptosis, an iron-dependent regulated necrotic pathway, has been implicated in the progression of AKI, while ferrostatin-1 (Fer-1), a selective inhibitor of ferroptosis, inhibited renal damage, oxidative stress and tubular cell death in AKI mouse models. However, the clinical translation of Fer-1 is limited due to its lack of efficacy and metabolic instability. In this study we designed and synthesized four Fer-1 analogs (Cpd-A1, Cpd-B1, Cpd-B2, Cpd-B3) with superior plasma stability, and evaluated their therapeutic potential in the treatment of AKI. Compared with Fer-1, all the four analogs displayed a higher distribution in mouse renal tissue in a pharmacokinetic assay and a more effective ferroptosis inhibition in erastin-treated mouse tubular epithelial cells (mTECs) with Cpd-A1 (N-methyl-substituted-tetrazole-Fer-1 analog) being the most efficacious one. In hypoxia/reoxygenation (H/R)- or LPS-treated mTECs, treatment with Cpd-A1 (0.25 μM) effectively attenuated cell damage, reduced inflammatory responses, and inhibited ferroptosis. In ischemia/reperfusion (I/R)- or cecal ligation and puncture (CLP)-induced AKI mouse models, pre-injection of Cpd-A1 (1.25, 2.5, 5 mg·kg-1·d-1, i.p.) dose-dependently improved kidney function, mitigated renal tubular injury, and abrogated inflammation. We conclude that Cpd-A1 may serve as a promising therapeutic agent for the treatment of AKI.

Effects of fermented cottonseed meal inclusions on growth performance, serum biochemical parameters and hepatic lipid metabolism of geese during 28-70 d of age

The aim of this study was to investigate the effects of solid-state fermented cottonseed meal (FCSM) inclusion levels on the growth performance, serum biochemical parameters and hepatic lipid metabolism in geese from 28 to 70 d of age. A total of 288 twenty-eight-d-old male geese were randomly divided into 4 treatments with FCSM levels of 0, 5, 15 and 25% including 0, 22.74, 67.33, 111.27 mg FG/kg diet, respectively. Each treatment contained 6 replicates and 12 birds per replicate. Treatments of FCSM inclusions from 0 to 25% had no effect on growth rate and feed intake in geese during d 28 to 70. The F/G ratio was increased (P < 0.05) in geese fed the diet with 25% FCSM compared with birds fed the diet with 0% FCSM. Treatment with 25% FCSM levels had no effect on the contents of TC, TG, HDL-C, LDL-C, but increased (P < 0.05) AST and ALT activities in serum of geese at d 70. Treatment with 25% FCSM increased the contents of FG, HDL-C, TC, C18:2n6, C20:4n6 and PUFA and decreased (P < 0.05) the contents of NEFA, SFA, MUFA in liver compared with treatment of 0% FCSM inclusion. Additionally, treatment with 25% FCSM decreased (P < 0.05) the PPARα, AMPK, and LXR mRNA expression related to lipid deposition, and increased (P < 0.05) PPARγ and ACC mRNA expression related to lipolysis in liver compared with birds fed the diet with 0% FCSM. Overall, treatment with 0 to 15% FCSM (<=67.33 mg FG/kg diet) had no adverse effects on the growth performance and lipid metabolism of geese. However, treatment fed 25% FCSM (111.27 mg FG/kg diet) decreased feed efficiency and promoted hepatic lipid deposition associated with the alteration of related gene expression in geese at 28 to 70 d of age.

Genetic and pharmacological inhibition of GRPR protects against acute kidney injury via attenuating renal inflammation and necroptosis

Gastrin-releasing peptide (GRP) binds to its receptor (GRP receptor [GRPR]) to regulate multiple biological processes, but the function of GRP/GRPR axis in acute kidney injury (AKI) remains unknown. In the present study, GRPR is highly expressed by tubular epithelial cells (TECs) in patients or mice with AKI, while histone deacetylase 8 may lead to the transcriptional activation of GRPR. Functionally, we uncovered that GRPR was pathogenic in AKI, as genetic deletion of GRPR was able to protect mice from cisplatin- and ischemia-induced AKI. This was further confirmed by specifically deleting the GRPR gene from TECs in GRPRFlox/Flox//KspCre mice. Mechanistically, we uncovered that GRPR was able to interact with Toll-like receptor 4 to activate STAT1 that bound the promoter of MLKL and CCL2 to induce TEC necroptosis, necroinflammation, and macrophages recruitment. This was further confirmed by overexpressing STAT1 to restore renal injury in GRPRFlox/Flox/KspCre mice. Concurrently, STAT1 induced GRP synthesis to enforce the GRP/GRPR/STAT1 positive feedback loop. Importantly, targeting GRPR by lentivirus-packaged small hairpin RNA or by treatment with a novel GRPR antagonist RH-1402 was able to inhibit cisplatin-induced AKI. In conclusion, GRPR is pathogenic in AKI and mediates AKI via the STAT1-dependent mechanism. Thus, targeting GRPR may be a novel therapeutic strategy for AKI.

Cpd-0225 attenuates renal fibrosis via inhibiting ALK5

Chronic kidney disease (CKD) is an increasing public health concern, characterized by a reduced glomerular filtration rate and increased urinary albumin excretion. Renal fibrosis is an important pathological condition in patients with CKD. In this study, we evaluated the anti-fibrotic effect of Cpd-0225, a novel transforming growth factor-β (TGF-β) type I receptor (also known as ALK5) inhibitor, in vitro and in vivo, by comparing its effect with that of SB431542, a classic ALK5 inhibitor, which has not entered the clinical trial stage owing to multiple side effects. Our data showed that Cpd-0225 attenuated fibrotic response in TGF-β1-stimulated human kidney tubular epithelial cells and repeated hypoxia/reoxygenation-treated mouse tubular epithelial cells. We further confirmed that Cpd-0225 improved renal tubular injury and ameliorated collagen deposition in unilateral ureteral obstruction-, ischemia/reperfusion-, and aristolochic acid-induced mouse models of renal fibrosis. In addition, molecular docking and site-directed mutagenesis showed that Cpd-0225 exerted a higher reno-protective effect than SB431542, by physically binding to the key amino acid residues, Lys232 and Lys335 of ALK5, thereby suppressing the phosphorylation of Smad3 and ERK1/2. Taken together, these findings suggest that Cpd-0225 administration attenuates renal fibrosis via ALK5-dependent mechanisms and displays a more effective therapeutic effect than SB431542. Thus, Cpd-0225 may serve as a potential therapeutic agent for the treatment of CKD.

Targeted inhibition of TGF-β type I receptor by AZ12601011 protects against kidney fibrosis

Renal fibrosis, a common feature of chronic kidney disease, causes the progressive loss of renal function, in which TGF-β₁ plays a critical role. In this study, we found that expression levels of TGF-β₁ and its receptor 1 (TGF-βR1) were both significantly increased in obstructive fibrosis kidneys. AZ12601011 is a small molecular inhibitor of TGF-βR1; however, its therapeutic potential for renal fibrosis remains unclear. During the experiments, AZ12601011 was applied to various models of renal fibrosis followed by unilateral ureteral obstruction (UUO) and ischemia/reperfusion (I/R) in vivo, in addition to renal tubular epithelial cells (TECs) challenged by hypoxia/reoxygenation (H/R) and TGF-β₁in vitro. Our results revealed that AZ12601011 ameliorated renal injuries and fibrosis shown by PAS, HE, and Masson staining, which was consistent with the decrease in Col-1 and α-SMA expression in the kidneys from UUO and I/R mice. Similarly, in vitro data showed that AZ12601011 inhibited the induction of Col-1 and α-SMA in both TECs treated with TGF-β₁ and H/R. In addition, the results of cellular thermal shift assay (CETSA), molecular docking, and western bolt indicated that AZ12601011 could directly bind to TGF-βR1 and block activation of the downstream Smad3. Taken together, our findings suggest that AZ12601011 can attenuate renal fibrosis by blocking the TGF-β/Smad3 signaling pathway and it might serve as a promising clinical candidate in the fight against fibrotic kidney diseases.

Insulin-like growth factor binding protein 7 promotes acute kidney injury by alleviating poly ADP ribose polymerase 1 degradation

The novel biomarker, insulin-like growth factor binding protein 7 (IGFBP7), is used clinically to predict different types of acute kidney injury (AKI) and has drawn significant attention as a urinary biomarker. However, as a secreted protein in the circulation of patients with AKI, it is unclear whether IGFBP7 acts as a key regulator in AKI progression, and if mechanisms underlying its upregulation still need to be determined. Here we found that IGFBP7 is highly expressed in the blood and urine of patients and mice with AKI possibly via a c-Jun-dependent mechanism, and is positively correlated with kidney dysfunction. Global knockout of IGFBP7 ameliorated kidney dysfunction, inflammatory responses, and programmed cell death in murine models of cisplatin-, kidney ischemia/reperfusion-, and lipopolysaccharide-induced AKI. IGFBP7 mainly originated from kidney tubular epithelial cells. Conditional knockout of IGFBP7 from the kidney protected against AKI. By contrast, rescue of IGFBP7 expression in IGFBP7-knockout mice restored kidney damage and inflammation. IGFBP7 function was determined in vitro using recombinant IGFBP7 protein, IGFBP7 knockdown, or overexpression. Additionally, IGFBP7 was found to bind to poly [ADP-ribose] polymerase 1 (PARP1) and inhibit its degradation by antagonizing the E3 ubiquitin ligase ring finger protein 4 (RNF4). Thus, IGFBP7 in circulation acts as a biomarker and key mediator of AKI by inhibiting RNF4/PARP1-mediated tubular injury and inflammation. Hence, over-activation of the IGFBP7/PARP1 axis represents a promising target for AKI treatment.

[Magnetic resonance imaging findings of intravascular papillary endothelial hyperplasia]

This paper analyzed the imaging data of intravascular papillary endothelial hyperplasia (IPEH) in 5 cases, with 1 male, 4 females, aged 28-61 years. MRI of IPEH revealed well-demarcated masses with central iso-or hypointensity and peripheral hyperintensity on T₂-weighted image(T₂WI), as well as peripheral enhancement or hyperintensity on T₂WI with/without hypointense foci, as well as homogeneous enhancement or heterogeneous enhancement with nonenhanced foci. CT demonstrated iso-or slightly hyperdense, well-circumscribed mass with bone destruction or calcification.

The Programmed Cell Death of Macrophages, Endothelial Cells, and Tubular Epithelial Cells in Sepsis-AKI

Sepsis is a systemic inflammatory response syndrome caused by infection, following with acute injury to multiple organs. Sepsis-induced acute kidney injury (AKI) is currently recognized as one of the most severe complications related to sepsis. The pathophysiology of sepsis-AKI involves multiple cell types, including macrophages, vascular endothelial cells (ECs) and renal tubular epithelial cells (TECs), etc. More significantly, programmed cell death including apoptosis, necroptosis and pyroptosis could be triggered by sepsis in these types of cells, which enhances AKI progress. Moreover, the cross-talk and connections between these cells and cell death are critical for better understanding the pathophysiological basis of sepsis-AKI. Mitochondria dysfunction and oxidative stress are traditionally considered as the leading triggers of programmed cell death. Recent findings also highlight that autophagy, mitochondria quality control and epigenetic modification, which interact with programmed cell death, participate in the damage process in sepsis-AKI. The insightful understanding of the programmed cell death in sepsis-AKI could facilitate the development of effective treatment, as well as preventive methods.

[Effects of vestibular spontaneous nystagmus on visual smooth pursuit function]

Objective: The aim of the study is to analyze the effects of vestibular spontaneous nystagmus(SN) on the smooth pursuit function of visual ocularmotor system. Methods: A total of 46 patients with acute unilateral peripheral vestibular syndrome with SN (26 cases of vestibular neuritis, 6 cases of Ramsay Hunt Syndrome (RHS) with vertigo, 14 cases of sudden deafness with vertigo) were included in this work. In the study group, the results of SPT and SN test with videonystagmography(VNG) were also reviewed. Taking SPT parameters, the influence of SN intensity on SPT gain, asymmetry and waveform and their correlation were analyzed.SPSS19.0 software was used for statistical analysis. Results: Among the 46 patients, there were 36 cases of SN pointing to the healthy side(SN intensity range of 2.68°/s-32.53°/s), and 10 cases of SN pointing to the affected side (SN intensity range of 2.66°/s-16.54°/s). SN intensity was divided into 3 groups, including light(0.50°/s-5.00°/s), medium(5.01°/s-10.00°/s) and strong(>10.01°/s), accounting for 14 cases(30.4%), 18 cases(39.1%) and 14 cases(30.4%), respectively. The differences of the gain of SPT to the fast phase and slow phase direction in the overall groups and light, medium and strong groups of SN intensity respectively were statistically significant(t_total=13.338, t_light=6.184, t_medium=8.436, t_strong=8.477, all of P<0.001). The difference of SPT gain in SN fast phase direction between groups with different SN intensity was statistically significant(F=9.639, P<0.001),there was no statistically significant difference in SPT gain between the groups on the SN slow phase direction(F=1.137, P=0.330).The SN intensity significantly negatively correlated with the SPT gain of the fast phase direction of SN (r=-0.433, P=0.003), that was, the SPT gain on the fast phase direction of SN decreased with the increase of SN intensity. There was no significant correlation between SN intensity and the gain of SPT on the slow phase direction of SN (r=-0.061, P=0.687). SPT waveform analysis showed that type I, type II and type III accounted for 8 cases(17.4%), 21 cases(45.6%) and 17 cases(37.0%), respectively. The corresponding mean values of SN intensity were (3.71±0.69)°/s, (7.44±1.88)°/s, (20.04±5.53)°/s, respectively, without type IV wave. The intensity of SN was positively correlated with the asymmetric value of the gain of SPT left and right(r=0.450,P=0.002). That was, with the increase of SN strength, the asymmetric value also increased, and the worse the asymmetry of the gain of SPT left and right pursuit was, the worse the SPT waveform was. Conclusion: SPT gain, asymmetry and SPT waveforms are all affected by SN, and the greater the intensity of SN, the greater the influence on the three. When SN is strong, type III waves may occur, suggesting that acute peripheral vestibular syndrome can also affect the visual ocularmotor systems.

Accuracy of high-pitch prospectively ECG-triggering CT coronary angiography for assessment of stenosis in 103 patients: comparison with invasive coronary angiography

AIM

To investigate the accuracy of high-pitch prospectively electrocardiogram (ECG)-triggering low-dose, dual-source computed tomography (CT) coronary angiography for assessing coronary artery stenosis compared with conventional coronary angiography.

MATERIALS AND METHODS

One hundred and three patients undergoing high-pitch CT coronary angiography (CTCA) and conventional coronary angiography (CCA) within 30 days were enrolled. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of high-pitch CTCA for detecting >50 and >70% stenosis were evaluated using CCA as the reference standard on a per-segment, per-vessel, and per-patient basis. Two experienced radiologists independently rated high-pitch CTCA images for quality using a four-point scale (1 = excellent, 4 = non-diagnostic) on a per-segment basis. The effective dose was calculated by multiplying the conversion coefficient of 0.028 by the dose-length product.

RESULTS

The mean heart rate of patients was 57 ± 6 beats/min. For detecting >50% stenosis, the sensitivity, specificity, PPV, and NPV of high-pitch CTCA were 89, 97, 87, and 97% on a per-segment basis; 91, 92, 92, and 91% on a per-vessel basis; and 99, 85, 96, and 94% on a per-patient basis. For detecting >70% stenosis, the sensitivity, specificity, PPV, and NPV of high-pitch CTCA were 96, 98, 90, and 99% on a per-segment basis. Coronary segments were rated as diagnostic in 98.6% (1355/1375) of cases (score 1, 72.5%; score 2, 23.1%; score 3, 3%; score 4, 1.4%). The effective dose of high-pitch CTCA was 1.51 ± 0.31 mSv.

CONCLUSION

High-pitch prospectively ECG-triggering dual-source CTCA provides good image quality and high diagnostic accuracy with a 1.51 mSv radiation dose.

Pharmacokinetics of verapamil in diabetic rats induced by combination of high-fat diet and streptozotocin injection

The aim of this study was to investigate effects of type 2 diabetes on the pharmacokinetics of verapamil after intravenous administration. Diabetes mellitus (DM) rats were induced by combination of high-fat diet (HFD) and streptozotocin. Plasma concentrations of verapamil in DM rats, rats fed with HFD, and control (CON) rats were measured after intravenous administration of 1 mg/kg verapamil and corresponding pharmacokinetic parameters were estimated. Area under the plasma concentration in DM rats was significantly smaller than that in CON rats. In vitro microsomal study showed that intrinsic clearance of verapamil in DM rats was significantly higher than those in CON rats. Compared to CON rats, higher intrinsic clearance was also observed in HFD rats. Western blot results demonstrated higher levels of CYP3A2 in DM and HFD rats, which was in line to activity of CYP3A. All the results gave a conclusion that diabetes may enhance metabolism of verapamil in rat, and the enhancement may partly result from induction of CYP3A.

Site-specific multi-stage CVD of large-scale arrays of ultrafine ZnO nanorods

Multi-stage growth of ZnO nanorod arrays has been carried out by Au-assisted chemical vapor deposition (CVD) in order to better understand and more precisely control the growth behaviors. It is evidenced that Au-catalyzed vapor-liquid-solid (VLS) growth only dominates the initial site-specific nucleation of the nanorods, while the subsequent growth is governed by a vapor-solid (VS) epitaxy mechanism. The sequential VLS and VS behaviors permit the fabrication of large-scale highly ordered arrays of ZnO nanorods with precisely tunable diameters and embedded junctions by controlling reactant concentration and nanorod top morphology. Based on the above results, two routes to fabricate ultrafine ZnO nanorod arrays are proposed and stepwise nanorod arrays with ultrafine top segment (~10 nm in diameter) have been achieved. Temperature-dependent photoluminescence (PL) and spatial resolved PL were carried out on the nanorod arrays and on individual nanorods, indicating high quality optical properties and tunable light emission along the length of the stepwise nanorods.

Concentration control of carbon nanotubes in aqueous solution and its influence on the growth behavior of fibroblasts

This work investigated the biological influence of water-soluble multiwalled carbon nanotubes (wsMWCNTs) on fibroblast cell growth as a function of concentration control in an aqueous solution. The wsMWCNTs were prepared by an optimal procedure of ultrasonication/concentrated acids oxidation. The concentration of wsMWCNT in the solution was quantified by an established calibration line. A stable concentration of 0.3mg/ml was obtained in the surfactant-free water. The physicochemical properties of wsMWCNTs were characterized using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), UV/VIS/NIR spectroscopy, and dynamic light scattering (DLS). Cell proliferation and the cell cycle were examined by MTS assay, flow cytometry and TEM respectively. Experimental results showed that the oxidation degree was a key factor that determined the concentration and stability of wsMWCNTs in the aqueous solution. The wsMWCNTs were able to enter into the cells and mainly accumulated in the cytoplasm. The wsMWCNTs-induced variations in cell proliferation and the cell cycle were concentration dependent. Cells cultivated with wsMWCNTs of 0.3mg/ml underwent a dramatic apoptosis. The proliferation was clearly suppressed when the cells were cultivated with wsMWCNTs of 0.03 mg/ml. There were no obvious influences on cell proliferation and the cell cycle when the concentration of wsMWNTs decreased to 0.01 mg/ml.

Long-term survival of cardiac allografts induced by cyclophosphamide combined with CTLA4Ig-gene transfer mediated by adenoviral vector

There is a need to achieve donor-specific tolerance in clinical organ transplantation, where potential benefits remain overshadowed by chronic rejection and the side-effects of long-term immunosuppressive therapy. It is known that the mature immune system in mice can be reprogrammed to accept a foreign graft as if it was "self". The AdCTLA4Ig-mediated gene transfer (SC) + cyclophosphamide (CP) treatment alone prolongs allograft survival but does not induce tolerance. However, in our study, the AdCTLA4Ig-mediated gene transfer combined with SC + CP treatment yielded significantly prolonged mean survival times (149.7 +/- 18.0 days), while those in the untreated or AdLacZ treated mice were rejected in normal fashion (5.3 +/- 0.5 and 5.2 +/- 0.4 days, respectively), and survival in the AdCTLA4Ig or SC + CP treated groups were 45.7 +/- 9.6 or 50.2 +/- 5.3 days, respectively. In conclusion, a protocol of AdCTLA4Ig + SC + CP improved the survival of DA-->LEW cardiac allografts.

Tomonaga-Luttinger liquid and Coulomb blockade in multiwall carbon nanotubes under pressure

We report that the conductance of macroscopic multiwall nanotube (MWNT) bundles under pressure shows power laws in temperature and voltage, as corresponding to a network of bulk-bulk connected Tomonaga-Luttinger liquids (LLs). Contrary to individual MWNTs, where the observed power laws are attributed to Coulomb blockade, the measured ratio for the end and bulk obtained exponents, approximately 2.4, can be accounted for only by LL theory. At temperatures characteristic of interband separation, it increases due to thermal population of the conducting sheets unoccupied bands.

Periodic ZnO nanorod arrays defined by polystyrene microsphere self-assembled monolayers

We demonstrate a low-cost and effective method to fabricate hexagonally patterned, vertically aligned ZnO nanorod arrays. Selective wet-etching is used to develop the catalyzing gold particle hexagonal pattern with the aid of a polystyrene microsphere self-assembled monolayer. The gold particles have tunable sizes independent of the polystyrene microsphere's diameter and are inherently round in shape. Each ZnO rod is grown individually from a catalyzing site via catalyst-initiated epitaxy, and the original hexagonal periodicity is well-preserved. The rods have flat ends, and the diameters of the rods can be controlled well by the amount of source materials. This method provides a promising way to create ZnO one-dimensional nanostructures for applications as two-dimensional photonic crystal, sensor arrays, nanolaser arrays, and optoelectronic devices.

Blockade of Both CD28/B7 and OX40/OX40L Co-Stimulatory Signal Pathways Prolongs the Survival of Islet Xenografts

CTLA4Ig, a recombinant fusion protein composed of the extracellular domain of human CTLA4 and the constant region of human IgG1, inhibits the interaction of CD28/B7 pathway by binding the B7 molecule. OX40Ig, a recombinant fusion protein composed of the extracellular domain of human OX40 and the constant region of human IgG1, abrogates the interaction of OX40/OX40L pathway by binding the OX40L on APCs. So blockade of CD28/B7 or OX40/OX40L co-stimulatory pathways alone in mice with CTLA4Ig or OX40Ig can result in finitely prolonging the survival of islet grafts (43.2 +/- 4.81 and 67.7 +/- 7.74 days, respectively). In this study, a novel replication-defective adenovirus containing both of the CTLA4Ig and OX40Ig genes, AdCTLA4Ig-IRES-OX40Ig, was constructed by homologous recombination and injected into the streptozocin-rendered diabetic BalB/c mouse recipients (H-2d) through the tail vein, at the same day, the freshly isolated islets from Lewis rats (RT-1) were transplanted under the left kidney capsule of the recipients. The results showed that the mean survival time of the islet xenografts in the AdCTLA4Ig-IRES-OX40Ig-treated diabetic mice was significantly prolonged (100.3 +/- 14.94 days), while those in the untreated or AdEGFP-treated mice were rejected in normal fashion (6.7 +/- 0.94 and 7.0 +/- 1.0 days, respectively). In conclusion, utilizing AdCTLA4Ig-IRES-OX40Ig in vivo which can simultaneously express CTLA4Ig and OX40Ig proteins can improve the survival of Lewis-->BalB/c islet xenografts.

Antileukemic Effect of Interleukin-7-Transduced Bone Marrow Stromal Cells in Mice Following Allogeneic T-Cell-Depleted Bone Marrow Transplantation

Impaired immune reconstitution following allogeneic bone marrow transplantation (BMT) remains a major obstacle to its clinical application. In this study, interleukin (IL)-7-transduced bone marrow stromal cells (MSC-IL7, 1 x 10(6)/mouse) were transfused into lethally irradiated C57BL/6 recipient mice. By day 40 after transplantation, the recipient mice were challenged with the lymphoma cell line EL4. MSC-IL7 co-transplantation protected recipient mice from leukemic mortality (MST >120 days after BMT vs mean survival time (MST) 70 days in the PBS group) It enhance the PFC count and DTH responses of recipients after transplantation. In conclusion, MSC mediated IL-7 gene therapy and may be a more feasible strategy to restore immune function following allo-TCD-BMT.

CTLA4-Fas Ligand Gene Transfer Mediated by Adenovirus Induce Long-Time Survival of Murine Cardiac Allografts

BACKGROUND

Fas ligand gene transfer to induce peripheral allograft tolerance in animal models has shown controversial results. The immunosuppression effects mediated by engineered FasL depend on whether alloreactive T cells are selectively deleted. In the present study, we tested the feasibility of a strategy to induce long-time survival by fusing CTLA4-FasL gene transfer in vivo.

METHODS

Cardiac allografts from DA(RT-1(a)) rats were transplanted heterotopically into the abdomens of LEW(RT-1(1)) rats. Plaque units (5x10(9)) of either AdCTLA4-FasL, AdCTLA4Ig, or AdEGFP were administered via the portal vein immediately after cardiac transplantation. The frequencies of helper T lymphocyte precursors (HTLp) and cytotoxic T lymphocyte precursors (CTLp) were determined by a combined single limiting dilution assay on days 5 and 20 after transplantation.

RESULTS

Cardiac allograft survival was significantly prolonged by either AdCTLA4-FasL or AdCTLA4Ig treatment(mean survival times [MST] of 71.0 +/- 3.7 and 45.7 +/- 2.4, respectively, n = 6) compared with untreated hosts or animals treated with AdEGFP(MST of 5.7 +/- 0.5 and 5.2 +/- 0.4, respectively, n = 6). In addition, treatment with AdCTLA4-FasL led to significantly prolonged allograft survival compared with AdCTLA4Ig treatment. Furthermore, the frequencies of HTLp and CTLp on day 20 among rats treated with AdCTLA4-FasL was lower than those on day 5, whereas frequencies of HTLp and CTLp on day 20 were similar with those on day 5 in the other groups.

CONCLUSION

These results suggest that administration of an adenovirus encoding fusion CTLA4-FasL gene to rat recipients effectively decreased the size of alloreactive T cells and induced long-term survival of cardiac allografts.

Improving the blood compatibility of polyurethane using carbon nanotubes as fillers and its implications to cardiovascular surgery

Blood compatibility has been an occlusion for biomaterials used in the cardiovascular system. In this work, a multiwalled carbon nanotubes-polyurethane composite (MWNT-PU) was prepared through a controlled co-precipitation. The surface chemical composition of treated carbon nanotubes was analyzed with XPS and the thermal behaviors of composite were characterized by DSC. The platelet adhesion and activation caused by the composite were evaluated by using SEM and flow cytometric analysis, respectively, and the disruption of red blood cells was analyzed through measuring the absorbance of free hemoglobin. The experimental results demonstrated that: (1) Multiwalled carbon nanotubes (MWNTs) with oxygen-containing functional groups could be well dispersed in polyurethane matrix through a controlled coprecipitation; (2) the composite surface displayed a significantly improved anticoagulant function, which can be indicative of the promising potentials of carbon nanotube-based materials in the implants and medical devices applied in blood-contacting environments.

Tunneling into multiwalled carbon nanotubes: coulomb blockade and the Fano resonance

Tunneling spectroscopy measurements of single tunnel junctions formed between multiwalled carbon nanotubes (MWNTs) and a normal metal are reported. Intrinsic Coulomb interactions in the MWNTs give rise to a strong zero-bias suppression of a tunneling density of states that can be fitted numerically to the environmental quantum-fluctuation theory. An asymmetric conductance anomaly near zero bias is found at low temperatures and interpreted as Fano resonance in the strong tunneling regime.

[Study on third-type immunoliposomes loaded drugs and the targeting in vitro and in vivo]

AIM

To study the preparation, targeting and pharmacodynamics of third-type immunoliposome loaded anticancer drugs.

METHODS

The monoclonal antibody of human bladder cancer was combined with the terminal of PEG-COOH (polyethyleneglycol carboxylic acid) that make the liposomes not only prolong circulation by the membrane protection of PEG, but also target by spreading the antibody on the liposomes surface. That was the third type immunoliposomes. According to this scheme, the IML-ADM (immunoliposome carried adriamycin) wes prepared in which ADM entrapment was efficient and stability was high and the antibody activity was kept.

RESULTS

The % survival of the targeting EJ cells treated with IML-ADM (ADM = 45.45 micrograms.mL-1) was 4.3% +/- 1.0%, but 72% +/- 6% for non-targeting LOVO cells in vitro; the tumor weight in nude mice which were implanted by EJ cells after 27 days were (39 +/- 25) mg, (135 +/- 32) mg, (598 +/- 240) mg treated by IML-ADM, SSL-ADM (steric stable lipsomes carried Adriamycin) and normal saline, respectively, in vivo.

CONCLUSION

The results confirmed that the immunoliposme-mediated targeting anticancer drug is a feasible way.

[Study on preparation and biodistribution of PEG-immunoliposomes with active carboxylic terminals]

AIM

In order to accumulate into its target specifically, the immunoliposomes must possess two characteristics: specific target efficiency to its target cells and prolonged circulation in blood. A new type of polyethylene glycol (PEG)-immunoliposomes carrying monoclonal antibodies at the distal end of PEG chains should be developed.

METHODS

A dipalmitoylphosphatidylethanolamine (DPPE) derivative of PEG with carboxyl group (DPPE-PEG3000-COOH) was newly synthesized. Small unilamellar liposomes were prepared from egg phosphatidyl choline and cholesterol (5:4, mol/mol) containing 6 mol% DPPE-PEG3000-COOH using reverse-phase evaporation method followed with bath sonication. Monoclonal antibody of human bladder cancer cell (BDI-1), which is highly specific to human bladder cancer cell, was conjugated to PEG-liposomes as well as mouse IgG at the distal end of polyethylene glycol chain. Doxorubicin was entrapped into these immunoliposomes by remote (NH4)2SO4 gradient loading method. The specific targeting efficiency of these immnoliposomes was tested by cytotoxicity test in vitro, enzyme-linked immune sorbent assay (ELISA) and indirect fluorescent immunoassay. Its biodistribution was carried out in mice.

RESULTS

The specific targeting efficiency of BDI-1 immunoliposomes (BDI-1-IML) to EJ cells has been demonstrated, in contrast to the nonspecific human colon carcinoma cells (LOVO). PEG-liposomes linked with mouse IgG (mouse-IgG-immunoliposomes, IgG-IML) displayed lower reticulo-endothelial systems (RES) uptake and longer circulation time than liposomes without PEG after intravenous injection.

CONCLUSION

The long circulation of these PEG-immunoliposomes in vivo, combined with its specific targeting efficiency demonstrated in vitro, guarantees the positive targeting efficiency of these immunoliposomes to its target carcinoma in vivo.

[Cloning and analysis of different regions of SRY promoter]

The luciferase systems were used to assay the promoter activity of SRY gene with clones of different parts of the 5' flanking region within 544 bp which has basal promoter activity. The results were that the 179 bp region from nt. -353 to nt. -174 upstream of the first ATG included a silent element; the 49 bp region from nt. -112 to nt. -63 included an enhanced element and the 63 bp region from nt. -174 to nt. -112 included an essential promoter sequency for gene transcription. These results give some important clues to elucidate the expression and regulation mechanisms of SRY gene.

Targeted diagnosis of bladder and ureteral carcinoma using radiolabelled BDI-1

The aim of this study is to investigate the possibility of radioimmunoimaging (RII) by radiolabelled anti-bladder carcinoma monoclonal antibody BDI-1 applied to diagnosis of bladder cancer and ureteral cancer. BDI-1 was labelled with 131I and 99mTc. The immunoreactivity, pharmacokinetics and biodistribution in mice were studied. RII was performed in 46 patients. The results showed that 131I, 99mTc-BDI-1 have satisfactory immunoreactivity and excellent tumor-locating properties. The blood clearance half-life T1/2alpha and T1/2beta were 35 h in the first phase and 151 h in the second phase, respectively. Thirty-nine patients were studied by an intravesical administration method; the sensitivity was 90.5%. Seven patients were studied by an intravenous administration method. The RII results of three cases with primary or recurrent bladder cancer and three cases with ureteral cancer were confirmed histologically. RII was negative in one patient with suspected lung metastasis that was shown on radiography. The investigation revealed that RII can be used as an auxiliary method for the detection of bladder cancer and may be valuable for the diagnosis of ureteral cancer.

Effect of berbamine on T-cell mediated immunity and the prevention of rejection on skin transplants in mice

Berbamine, an ingredient of Berberis, which itself is widely utilized in Chinese folk-medicine has been used as a source of leukogenics, anti-arrhythmics and anti-hypertensives. In recent years, the immunosuppressive effects of berbamine has been demonstrated. In order to further investigate the value of berbamine as an immunosuppressive agent, the delayed type hypersensitivity reaction (DTH) response with sheep red blood cells (SRBC), the mixed lymphocyte reaction (MLR) and a skin model of allograft rejection on mice were studied. Berbamine showed suppressive effects on DTH and MLR and significantly prolonged allograft survival compared with untreated transplanted mice. The results indicate that berbamine may be a potential agent in clinical transplantation.

In situ DNA fragmentation assay for detection of apoptosis in paraffin-embedded tissue sections. Technical considerations

Detection, by light microscopy, of cells in situ undergoing apoptosis has been improved by use of an in situ apoptosis (DNA fragmentation) assay on formalin-fixed and paraffin-embedded tissue sections. We studied conditions of tissue preparation and fixation that may affect the test results. In this study, we intended to determine whether archival tissues prepared under unknown conditions can be used for the in situ apoptosis assay. All tissue sections were pretreated with Proteinase K, followed by incubation with biotinylated 11-deoxyuridine triphosphate in terminal deoxynucleotidyl transferase and then avidin-biotin-peroxidase complex. The following formalin-fixed and paraffin-embedded histologic sections were tested: (1) normal tissues from surgically resected specimens fixed immediately or stored at 4 degrees C and then fixed after 1, 2, 4, 6, or 24 hours; (2) archival autopsy material from histologically normal tissues; and (3) freshly prepared normal tissues from C57 mice. We observed that fixation- and prefixation-elapsed times do not adversely affect the results of the assay. Similar, if not identical results were seen in archival human tissues stored for up to 25 years, the normal tissues freshly prepared from surgical specimens, and the tissues from C57 mice. We conclude that the in situ assay of DNA fragmentation is rapid, sensitive, and reproducible. The use of formalin-fixed and paraffin-embedded archival material as old as 25 years opens the way for a variety of studies of apoptosis in diverse pathologic states.

The glycophorin A gene family in gorillas: structure, expression, and comparison with the human and chimpanzee homologues

Homologues of MN blood group antigens, encoded by members of the glycophorin A (GPA) gene family, are expressed in man, anthropoid apes, and some species of Old World monkeys. Previous studies had shown that a three-gene framework, most closely related to that in man, is present in the chimpanzee. Here we report the genomic structure, transcript map, and protein expression of the GYPA locus in gorillas. Compared to the corresponding human and chimpanzee homologues, gorilla GPA, GPB, and GPB/E genes each showed a high degree of sequence identity, with the same exon-intron organization. However, the expression of exons III, IV or V encoding the extracellular or membrane domains of homologous glycophorins varied among the three species. Gorilla GPA and GPB/E genes were unique in that the former occurred in two allelic forms with or without the expression of exon III, whereas the latter contained one (psi exon III) instead of two silenced exons (psi exons III and IV). Differences from human but not chimpanzee GPA also included the presence of a hybrid M/N epitope and the absence of the sequon for N-glycosylation. Owing to the retention of a functional exon III, gorilla GPB was more similar to chimpanzee GPB than human GPB. A transspecies allele was identified in the gorilla that gave rise to the Henshaw (He)-like antigen similar to that found in man. These results provide further insight into the model for evolution of the GPA gene family, indicating that the mechanisms underlying inter- and intraspecific polymorphism of glycophorins could predate the divergence of gorillas as the consequence of gene duplication and diversification.

Large-Scale Synthesis of Aligned Carbon Nanotubes

Large-scale synthesis of aligned carbon nanotubes was achieved by using a method based on chemical vapor deposition catalyzed by iron nanoparticles embedded in mesoporous silica. Scanning electron microscope images show that the nanotubes are approximately perpendicular to the surface of the silica and form an aligned array of isolated tubes with spacings between the tubes of about 100 nanometers. The tubes are up to about 50 micrometers long and well graphitized. The growth direction of the nanotubes may be controlled by the pores from which the nanotubes grow.

Apoptosis is a major pathway responsible for the resolution of type II pneumocytes in acute lung injury

Proliferation of type II pneumocytes has been linked to a repair process during the early phase of acute lung injury, and it persists for a variable period. The mechanisms responsible for their dissolution and/or disappearance are not known, but we speculate that it may be partly due to apoptosis. Sections of lung tissue from patients with acute lung injury (n = 7) and chronic interstitial pneumonia (n = 14) were stained for detection of apoptotic cells via specific labeling of nuclear DNA fragmentation. Results were correlated with those of proliferating cell nuclear antigen (PCNA) staining for cell proliferation. Marked apoptosis of CD68-negative type II pneumocytes (30 to 80%) was detected in four of the seven (57%) cases of acute lung injury. In these cases, representing the resolution phase of acute lung injury, PCNA positivity in pneumocytes was extremely rare. In the 3 other cases in the acute/proliferative phase, apoptotic type II pneumocytes were rare whereas PCNA expression was quite evident in these cells. In chronic interstitial pneumonia, only rare type II pneumocytes (< 5%) exhibited apoptosis, and they showed variable staining for PCNA (up to 70%). We conclude that proliferation of type II pneumocytes occurs during the early phase of acute lung injury and is of variable extent and duration. In the resolution phase of acute lung injury, extensive apoptosis of type II pneumocytes is largely responsible for the disappearance of these cells. The time frame within which the apoptotic response occurs is variable and is likely to be dependent upon the specific etiology and extent of the injury. In chronic interstitial pneumonia, type II pneumocytes proliferate continuously, although to a much lesser degree than in the early phase of acute lung injury, and are minimally apoptotic.

In situ apoptosis assay for the detection of early acute myocardial infarction

Detection and age determination of myocardial infarction (MI) is often necessary in both clinical and pathological settings. Conventional histopathological techniques are of limited utility in the demonstration of myocardial ischemic cell death (MICD) within the first 6 hours of MI. In this study, an in situ apoptosis assay was evaluated for the determination of early MICD or early MI. Sections of formalin-fixed, paraffin-embedded archival tissue blocks from 80 hearts were stained for the presence of apoptotic cells by specific labeling of nuclear DNA fragmentation. Conventional hematoxylin and eosin stain showed acute MI (group A, n = 32), equivocal evidence for MICD or early infarction (group B, n = 35), or no abnormal findings (group C, n = 13). The sensitivity and specificity of the in situ apoptosis assay for MICD were confirmed in groups A and C patients. We showed that apoptosis of myocardial cells can occur after ischemic myocardial cell injury. Virtually all documented cases of acute MI (group A) revealed a sizeable distribution of apoptotic cells visible on gross examination of glass slides. Special attention was given to patients in group B, who were at high risk for MI and for suspected but not proved cardiac death. In this group, 34/35 cases (97%) showed focal or diffuse nuclear positivity of varying degrees for apoptosis, confirming the presence of MICD. A sizeable distribution of apoptotic cells, similar to that observed in group A, was noted in 13/35 cases (37%) of group B, suggesting acute MI in these cases. The in situ assay of DNA fragmentation can detect MICD while the histological diagnosis is still inconclusive. It is estimated that with this assay one can detect MICD as early as 2 to 4 hours.

Human red blood cell Wright antigens: a genetic and evolutionary perspective on glycophorin A-band 3 interaction

The Wright (Wra/Wrb) blood group polymorphism is defined by an allelic change (Lys658Glu) in the band 3 protein; nevertheless, the Wrb antigen apparently requires glycophorin A (GPA) for surface presentation. To gain insight into the structural basis for this protein-protein interaction and delineate its relationship with Wrb antigen expression, we investigated GPA and band 3 sequence polymorphisms occurring in rare humans and nonhuman primates. The lack of GPA or amino acid residues 59 through 71 of GPA results in the absence of Wrb from human red blood cells (RBCs) exhibiting the MkMk, En(a-), or MiV phenotype. However, the SAT homozygous cells carried a Glu658 form of band 3 and a hybrid glycophorin with the entire GPA extramembrane domain from residues 1 through 71, yet expressed no Wrb antigen. This finding suggests that formation of the Wrb antigenic structure is dependent on protein folding and that the transmembrane junction of GPA is important in maintaining the required conformation. Comparative analyses of GPA and band 3 homologues led to the identification in the interacting regions of conserved and dispensable amino acid residues that correlated with the Wrb positive or negative status on nonhuman primates. In particular, the chimpanzee RBCs cells expressed Wrb and the Glu658 form of band 3, which is identical to humans, but their GPA contained the Gly rather than Arg residue at position 61. Taken together, the results suggest that (1) Arg61 of GPA and the proposed Arg61-Glu658 charge pair are not crucial for Wrb antigen exhibition and (2) the role of GPA for interaction with band 3, including Glu658, probably involves a number of amino acid residues located in the alpha-helical region and transmembrane junction.

Absence of T-cell- and B-cell-specific transcription factors TCF-1, GATA-3, and BSAP in Hodgkin's Reed-Sternberg cells

Based on the presence of T cell receptor-beta (TcR-beta) gene rearrangements in L428 and HDLM-1 cells, the expression of CD2 in HDLM-1 cells, and the presence of immunoglobulin heavy-chain (IgH) gene rearrangement in KM-H2 cells, some researchers have concluded that these long-term cell lines derived from patients with Hodgkin's disease are lymphoid in nature. The information obtained from these cell lines has also been used in arguments for a lymphoid origin of H-RS cells in tissue despite the frequent absence of lymphoid markers and Ig/TcR gene rearrangements in these cells. We questioned whether one can use the limited expression of lymphoid markers or the limited gene rearrangement to conclude that H-RS cells have a lymphoid origin, because these markers may be aberrant in tumor cells. In this study, we examined the expression of two T-cell-specific transcription factors (TCF-1 and GATA-3) and one B-cell-specific transcription factor (BSAP) in cultured H-RS cells by using a gel mobility shift assay. The sensitivity and specificity of this assay for determination of cell lineage have been established in a large number of cultured human and murine cell lines. All three types of H-RS cell lines were consistently negative for BSAP, TCF-1, and GATA-3. The absence of GATA-3 was confirmed in H-RS cells in tissues by an in situ hybridization technique. Virtually all B-cell lines, with the exception of some myeloma cell lines, are positive for BSAP, which is the transcription factor for promoters for several B-cell markers, including VpreB1, lambda 5, CD19, and CD20. All T-cell lines tested were positive for TCF-1 and GATA-3, which are the transcription factors for promoters for several T-cell-restricted markers, including CD2, CD3, TcR, and lck. The absence of BSAP, TCF-1, and GATA-3 clearly indicates an underlying difference between H-RS cells and lymphoid cells.

Sequence diversification and exon inactivation in the glycophorin A gene family from chimpanzee to human

In humans, the allelic diversity of MNSs glycophorins (GP) occurs mainly through the recombinational modulation of silent exons (pseudoexons) in duplicated genes. To address the origin of such a mechanism, structures of GPA, GPB, and GPE were determined in chimpanzee, the only higher primate known to have achieved a three-gene framework as in humans. Pairwise comparison of the chimpanzee and human genes revealed a high degree of sequence identity and similar exon-intron organization. However, the chimpanzee GPA gene lacks a completely formed M- or N-defining sequence as well as a consensus sequence for the Asn-linked glycosylation. In the case of the GPB gene, exon III is expressed in the chimpanzee but silenced, as a pseudoexon, in the human. Therefore, the protein product in the chimpanzee bears a larger extracellular domain than in the human. For the GPE genes, exon III and exon IV have been inactivated by identical donor splice-site mutations in the two species. Nevertheless, the chimpanzee GPE-like mRNA appeared to be transcribed from a GPB/E composite gene containing no 24-bp insertion sequence in exon V for the transmembrane domain. These results suggest a divergent processing of exonic units from chimpanzee to human in which the inactivation of GPB exon III preserved a limited sequence repertoire for diversification of human glycophorins.

Enhancement of interleukin-2 production and its mRNA expression by dihydroartemisinin

Immunoregulatory properties of a novel antimalarial drug dihydroartemisinin (DHA) were investigated in vitro. DHA 0.5-5 mumol.L-1 enhanced the lymphocyte proliferation induced by Con A. Interleukin 2 (IL-2) production and its mRNA expression by both Con A-stimulated mouse splenocytes and a T cell line LBRM-33-1A5 were also augmented by DHA. In contrast, DHA 0.5-5 mumol.L-1 did not show any effect on the lipopolysaccharides (LPS)-induced lymphocyte proliferation and the spontaneous and mitogen-induced proliferation of transformed T cells. These results indicated that DHA might regulate lymphocyte responses through the induction of IL-2 production and that the enhanced T cell proliferation and IL-2 production might be mediated through different pathways.

Triptolide suppresses T-lymphocyte proliferation by inhibiting interleukin-2 receptor expression, but spares interleukin-2 production and mRNA expression

The purpose of this study was to elucidate the mechanism of action of triptolide on the T-lymphocyte-mediated immune response. Lymphocytes were incubated with a suboptimal dose of Con A or PHA in the presence or absence of varying doses of triptolide to assess the effect of triptolide on lymphocyte proliferation, interleukin-2 (IL-2) production and IL-2 receptor expression. Then, Con A or PHA induced T-blast cells were cultured with a sufficient dose of recombinant human IL-2 in the presence or absence of triptolide to evaluate the effect of triptolide on the interaction of IL-2 and IL-2 receptors. The effect of triptolide on the immune response in vivo was also investigated. The results of these studies clearly demonstrated that triptolide selectively inhibited the T-lymphocyte proliferative response to Con A and PHA, but had less effect on LPS-induced B-lymphocyte proliferation. Triptolide also suppressed the expression of IL-2 receptors on PHA induced T-blast cells, but did not alter the production of IL-2 by mouse splenic cells and human tonsil lymphocytes. Furthermore, the results also showed that triptolide at higher concentration had a slight inhibitory effect on the interaction of IL-2 and IL-2 receptors, and addition of exogenous IL-2 did not reverse the inhibiting action of triptolide on T-cell proliferation. Taken together, these results suggest that triptolide inhibits T-lymphocyte proliferation mainly by affecting IL-2 receptor expression rather than IL-2 production.

Artemisinin and its derivatives enhance T lymphocyte-mediated immune responses in normal mice and accelerate immunoreconstitution of mice with syngeneic bone marrow transplantation

Artemisinin and its derivatives, dihydroartemisinin and sodium artesunate, enhanced DNA synthesis of mouse spleen cells that had been activated with alloantigens or T cell mitogen Con A, but not B cell mitogen LPS, both in vitro and ex vivo. In vivo experiments showed that DTH response and antibody response against sheep erythrocytes were augmented in sodium artesunate-treated animals. In addition, sodium artesunate, a representative of these compounds, increased IL-2 production from mouse splenocytes stimulated with Con A. Because of the long-term T cell function deficiency in mice after bone marrow transplantation, the effect of sodium artesunate on the immune reconstitution was assessed. The results demonstrated that 10 mg/kg sodium artesunate significantly accelerated the immune reconstitution in mice after syngeneic bone marrow transplantation. These data suggested that artemisinin and its derivatives appeared to promote T cell function selectively, and these compounds had a potential application for the recovery of immune function.

Expression of interleukin-6 in Castleman's disease

Although mixed forms of Castleman's disease (CD) may occur, two classically recognized forms are the angiofollicular (hyaline vascular [V]) variant and the plasma cell (P) variant. The two forms of CD differ greatly in their clinical and histopathologic manifestations. Plasma cell CD is characterized by the presence of hyperplastic germinal centers (GCs) and sheets of plasma cells in the interfollicular areas. In this study we demonstrated an abundant expression of interleukin-6 (IL-6) in most GC B cells and in the numerous immunoblastoid B cells in the mantle zone and interfollicular areas in CD-P. Patients with CD-P also have an elevated serum IL-6 level. The increased IL-6 production is responsible for the marked plasma cell infiltration in lymph nodes and bone marrow as well as for the elevated gammaglobulin level in serum. In contrast, CD-V is distinguished by the presence of atrophic GCs, which often are populated by cytologically atypical follicular dendritic reticulum (FDR) cells, as well as by sheets of T-zone plasmacytoid histiocytes and increased numbers of capillaries in the interfollicular areas. In contrast to the findings in CD-P, we did not observe significant expression of IL-6 in GC cells or in immunoblastoid cells in CD-V; this may account for the paucity of plasma cells in this form of CD. The reason for the atypical changes in FDR cells as well as the increases in T-zone plasmacytoid histiocytes and capillaries seen in CD-V are not known inasmuch as no cytokines, such as IL-1, IL-4, IL-6, IL-7, IL-8, IL-9, tumor necrosis factor-alpha, granulocyte-macrophage colony-stimulating factor, or granulocyte colony-stimulating factor, were detectable in tissues. It is possible that in CD-V the atypical change in FDR cells could lead to a disturbance of B-lymphocyte/FDR cell interaction and subsequently to poor development of GCs. The study clearly indicates that the histopathologic and clinical features of CD vary greatly depending on the capacity of activated B cells to produce IL-6. However, lack of IL-6 secretion by GC cells alone cannot explain the histopathologic alterations in CD-V.

Abundant expression of transforming growth factor-beta 1 and -beta 2 by Hodgkin's Reed-Sternberg cells and by reactive T lymphocytes in Hodgkin's disease

The depressed cellular immunity observed in patients with Hodgkin's disease (HD) has been attributed to production of transforming growth factor (TGF)-beta or TGF-beta-like substances by Hodgkin's Reed-Sternberg (H-RS) cells. The TGF-beta produced by L-428 cells (an H-RS cell line) is a 130-kd molecular weight glycoprotein that apparently differs from the TGF-beta (molecular weight, 25 kd) produced by most lymphoid and hematopoietic cells. Among several distinct types of TGF-beta that have been purified, only TGF-beta 1 and TGF-beta 2 have thus far been identified in hematopoietic cells. By using monoclonal antibodies (1D11 and 3C7) and oligonucleotide probes specific for TGF-beta 1 and TGF-beta 2, were confirmed that a cultured H-RS cell line, KM-H2, can produce both TGF-beta types, whereas another line, HDLM-1, produces only TGF-beta 1. Despite the abundance of mRNA in both of these cells, only small amounts of TGF-beta activity were detected, probably because of rapid degradation of TGF-beta 1 mRNA by specific nuclease. No degraded TGF-beta 2 RNA products were observed in KM-H2 cells. The TGF-beta produced by both types of H-RS cells had a molecular weight of approximately 25 kd. In tissues expression of TGF-beta was observed in a small portion (30%) of H-RS cells in 16 of 20 cases examined. A large number of small to medium-sized lymphoid cells (T lymphocytes) in tissues involved by HD also were positive for TGF-beta. These results indicate that there is functional heterogeneity among H-RS cells, and that H-RS cells are not the only source of TGF-beta in tissues involved by HD. Hodgkin's Reed-Sternberg cells are known to secrete several other cytokines, including interleukin (IL)-1, IL-6, and tumor necrosis factor-alpha. These cytokines could be responsible for the increased number of T lymphocytes in tissues involved by HD. Furthermore, T lymphocytes can respond to IL-1 and IL-6 secreted by H-RS cells by increasing their production of TGF-beta. Abundant expression of TGF-beta by T lymphocytes was not observed in lymphoid tissues other than those involved by HD.

Thrombomodulin activity and localization

An overview on the properties, actions and localization of thrombomodulin (TM) in situations of tissue injury and in selected tumors is presented. The localization and activity of TM after injury to vascular endothelium shows that following balloon catheter denudation of the endothelium of the rabbit aorta, the activity and immunohistochemical staining is markedly reduced. The functional and antigenic levels approach the control levels approximately one week after the initial injury. The results suggest that the neointimal smooth muscle cells express TM. This phenotypic plasticity of the neointimal smooth muscle cells may be important in conferring thrombo-resistance to the lumenal lining cells of vessels after injury. Studies are also reviewed on the use of soluble recombinant TM to prevent thrombosis after ligature of vessels in an experimental model. Further characterization on the immunohistochemical distribution of TM in normal tissues and tumors shows that staining with a monoclonal anti TM antibody can be very useful in separating mesotheliomas from pulmonary adenocarcinomas. These studies may lead to insights concerning the role of TM in tissue-injury-repair and tissue differentiation.

Pathogenic significance of interleukin-6 in angioimmunoblastic lymphadenopathy-type T-cell lymphoma

Patients with angioimmunoblastic lymphadenopathy (AILD)-type T-cell lymphoma may develop hypergammaglobulinemia. Among four cases of AILD-type T-cell lymphoma that we have studied, we detected a correlation between the number of plasma cells in tissue and the extent of interleukin-6 (IL-6) expression in lymphoma cells. We did not detect IL-6 in three patients who had no hypergammaglobulinemia and whose tissues showed only minimal plasma cell infiltration. In the fourth patient we observed an abundant IL-6 production by lymphoma cells, which accounted for a B-cell plasmacytic tissue response and for hypergammaglobulinemia. The pathogenic significance of IL-6 was substantiated by a concomitant decrease in the serum IL-6 level, measurable tumor mass, and immunoglobulin levels, as well as by a decline in the proportion of plasmacytoid cells in peripheral blood promptly on administration of chemotherapy. Plasmacytoid B cells could be maintained in culture in the presence of IL-6, but viability was lost on co-incubation with anti-IL-6. Interleukin-1 and tumor necrosis factor were not produced by T lymphoma cells and were incapable of sustaining plasmacytoid B-cell viability in vitro. Small amounts of IL-4 were noted in T lymphoma cells. Thus, in this case of AILD-type T-cell lymphoma, tumor cells with a T-cell phenotype produced IL-6 in large quantities, explaining the accompanying B-cell and plasmacytic histologic changes and humoral disease manifestations, including marked hypergammaglobulinemia. Although not all cases of AILD-type T-cell lymphoma have an accompanying plasma cell proliferation and hypergammaglobulinemia, and although the cytokine network in these patients may be more complex than has been recognized, this case with IL-6 expression serves to illustrate the utility of cytokine assays in the analysis of the histopathologic and clinical heterogeneities of peripheral T-cell lymphomas.

Thrombomodulin expression in malignant pleural mesothelioma and pulmonary adenocarcinoma

Thrombomodulin (TM) is a glycoprotein of molecular weight 75,000 kd that is normally present in restricted numbers of cells, including endothelial and mesothelial cells. In this study, the authors tested the possibility of using anti-TM to facilitate the diagnosis of mesothelioma. All of the 31 mesotheliomas and the two mesothelioma cell lines (MS-1 and MS-2) tested were stained positively with anti-TM. The specificity of anti-TM staining in mesothelioma cells was further confirmed by in situ hybridization of MS-1 cells with a TM-specific probe. The expression of TM in MS-1 cells was increased markedly when these cells were induced by 12-0-tetradecanyl phorbol 13-acetate (TPA) to differentiate. The expression of TM in mesothelioma cells, however, did not correlate with any particular phase of the cell cycle. In an attempt to differentiate pleural mesothelioma from pulmonary adenocarcinoma, the authors compared the expression of TM, carcinoembryonic antigen (CEA), and Leu M1 in these two types of tumors. Only four of 48 (8%) pulmonary adenocarcinomas were stained positively by antibodies to TM. Therefore, immunohistochemical staining with antibodies to TM yielded 100% sensitivity and 92% specificity for diagnosis of mesothelioma. All of the mesotheliomas stained negatively for CEA and Leu M1, except for one, which showed minimal focal positivity for Leu M1. In contrast, 79% and 60% of adenocarcinomas stained positively for CEA and Leu M1, respectively. These findings suggest that immunocytochemical staining with anti-TM should be added to the battery of tests to increase the diagnostic sensitivity and specificity for differentiating mesothelioma from pulmonary adenocarcinoma.

Functional heterogeneity and pathogenic significance of interleukin-6 in B-cell lymphomas

A possible autocrine effect of interleukin-6 (IL-6) on the growth and differentiation of the tumor cells of 55 B-cell lymphomas was examined. Interleukin-6 was detected in a few types of B-cell lymphomas, including polymorphic immunocytoma (PI), small lymphocytic lymphoma (SLL), and immunoblastic lymphoma (IBL) with or without plasmacytoid differentiation. In PI and in IBL with plasmacytoid differentiation (IBL-P), IL-6 was detected only in immunoglobulin-containing plasmacytoid cells, and it was absent from most proliferating (Ki-67/PCNA-positive) lymphoma cells. In SLL, IL-6 was not observed in lymphoplasmacytoid cells; instead, IL-6 was observed in transformed (Ki-67/PCNA-positive) tumor cells in proliferation centers. The lymphoplasmacytoid cells in SLL exhibited a phenotype (IL-6/glutathione-S-transferase-pi [GST-pi]-negative), different from that of normal plasma cells (IL-6-negative/GST-pi-positive) and from the plasmacytoid cells (IL-6/GST-pi-positive) in PI and IBL-P. In IBL without obvious plasmacytoid differentiation, IL-6 was detected in most tumor cells that were highly proliferative (Ki-67/PCNA-positive). In this study, IL-6 was undetectable in most lymphomas related to follicular centers, in lymphoblastic lymphoma, in small noncleaved cell lymphomas of the Burkitt and non-Burkitt types, and in diffuse large cell lymphoma. This finding is compatible with a previous finding that IL-6 mRNA was absent from follicular center cells in reactive lymphoid tissues. The functions of IL-6 in these lymphomas may be quite diverse. It appears that IL-6, as an autocrine factor, is responsible for the plasmacytoid differentiation of lymphoma cells in IP and some IBL (IBL-P). The differentiation of lymphoplasmacytoid lymphoma cells in SLL, however, may not be mediated by an autocrine IL-6 mechanism. Interleukin-6 may provide a growth signal, rather than acting as a differentiation factor, for some IBL cells and for some transformed tumor cells in proliferation centers in SLL.

Immunosuppression of triptolide and its effect on skin allograft survival

In this study the immunosuppressive properties of triptolide were evaluated. Triptolide was found to inhibit skin allograft rejection in a dose-dependent manner. This inhibitory effect was time dependent. Triptolide at 0.1 mg/kg/day significantly prolonged the graft survival when triptolide was given for 9 days after transplantation, but not before transplantation. In vitro studies showed that triptolide markedly suppressed cytotoxic T-lymphocyte (CTL) induction and mixed lymphocyte reaction (MLR) at concentrations ranging from 0.08 to 10 ng/ml. The inhibition on MLR was also significant when triptolide was added to the cultures at 36 h after initial incubation. Furthermore, exogenous IL-2 did not reverse this inhibitory effect of triptolide. Our results suggest that triptolide inhibits lymphocyte activation at a relatively late stage, and its effect on immune response is not exerted through altering IL-2 production.