c-Jun N-terminal kinase (JNK)-interacting protein-1b/islet-brain-1 scaffolds Alzheimer's amyloid precursor protein with JNK.

Using a yeast two-hybrid method, we searched for amyloid precursor protein (APP)-interacting molecules by screening mouse and human brain libraries. In addition to known interacting proteins containing a phosphotyrosine-interaction-domain (PID)-Fe65, Fe65L, Fe65L2, X11, and mDab1, we identified, as a novel APP-interacting molecule, a PID-containing isoform of mouse JNK-interacting protein-1 (JIP-1b) and its human homolog IB1, the established scaffold proteins for JNK. The APP amino acids Tyr(682), Asn(684), and Tyr(687) in the G(681)YENPTY(687) region were all essential for APP/JIP-1b interaction, but neither Tyr(653) nor Thr(668) was necessary. APP-interacting ability was specific for this additional isoform containing PID and was shared by both human and mouse homologs. JIP-1b expressed by mammalian cells was efficiently precipitated by the cytoplasmic domain of APP in the extreme Gly(681)-Asn(695) domain-dependent manner. Reciprocally, both full-length wild-type and familial Alzheimer's disease mutant APPs were precipitated by PID-containing JIP constructs. Antibodies raised against the N and C termini of JIP-1b coprecipitated JIP-1b and wild-type or mutant APP in non-neuronal and neuronal cells. Moreover, human JNK1beta1 formed a complex with APP in a JIP-1b-dependent manner. Confocal microscopic examination demonstrated that APP and JIP-1b share similar subcellular localization in transfected cells. These data indicate that JIP-1b/IB1 scaffolds APP with JNK, providing a novel insight into the role of the JNK scaffold protein as an interface of APP with intracellular functional molecules.

Secreted Abeta does not mediate neurotoxicity by antibody-stimulated amyloid precursor protein.

Antibodies against APP, a precursor of Abeta deposited in Alzheimer's disease brain, have been shown to cause neuronal death. Therefore, it is important to determine whether Abeta mediates antibody-induced neurotoxicity. When primary neurons were treated with anti-APP antibodies, Abeta40 and Abeta42 in the cultured media were undetectable by an assay capable of detecting 100 nM Abeta peptides. However, exogenously treated Abeta1-42 or Abeta1-43 required >3 microM to exert neurotoxicity, and 25 microM Abeta1-40 was not neurotoxic. Glutathione-ethyl-ester inhibited neuronal death by anti-APP antibody, but not death by Abeta1-42, whereas serum attenuated toxicity by Abeta1-42, but not by anti-APP antibody. Using immortalized neuronal cells, we specified the domain responsible for toxicity to be cytoplasmic His(657)-Lys(676), but not the Abeta1-42 region, of APP. This indicates that neuronal cell death by anti-APP antibody is not mediated by secreted Abeta.

A rescue factor abolishing neuronal cell death by a wide spectrum of familial Alzheimer's disease genes and Abeta.

Through functional expression screening, we identified a gene, designated Humanin (HN) cDNA, which encodes a short polypeptide and abolishes death of neuronal cells caused by multiple different types of familial Alzheimer's disease genes and by Abeta amyloid, without effect on death by Q79 or superoxide dismutase-1 mutants. Transfected HN cDNA was transcribed to the corresponding polypeptide and then was secreted into the cultured medium. The rescue action clearly depended on the primary structure of HN. This polypeptide would serve as a molecular clue for the development of new therapeutics for Alzheimer's disease targeting neuroprotection.

Insulin-like growth factor I (IGF-I) protects cells from apoptosis by Alzheimer's V642I mutant amyloid precursor protein through IGF-I receptor in an IGF-binding protein-sensitive manner.

It has been found that insulin-like growth factor I (IGF-I) exerts cytoprotection against Abeta amyloid-induced neuronal cell death. Deposits of Abeta amyloid are one of the pathological hallmarks of Alzheimer's disease (AD). Here, we examined whether IGF-I exerts protective activity against cell death induced by a familial AD (FAD)-linked mutant of amyloid precursor protein (APP), and we found that IGF-I protected cells from toxicity of FAD-associated V642I mutant of APP in multiple cell systems. IGFBP-3 blocked this action of IGF-I, but not of des(1-3)IGF-I, which was as active as IGF-I in the presence of IGFBP-3. The data also demonstrated that the IGF-I receptor (IGF-IR) mediates the protective activity of IGF-I. The antagonizing function of the IGF-I/IGF-IR system against V642I-APP, which is further antagonized by IGFBP-3, provides a molecular clue to the understanding of AD pathophysiology and to the establishment of potential therapy for AD.

Safety and biological efficacy of an adeno-associated virus vector-cystic fibrosis transmembrane regulator (AAV-CFTR) in the cystic fibrosis maxillary sinus.

OBJECTIVE: The host immune response and low vector efficiency have been key impediments to effective cystic fibrosis transmembrane regulator (CFTR) gene transfer for cystic fibrosis (CF). An adeno-associated virus vector (AAV-CFTR) was used in a phase I dose-escalation study to transfer CFTR cDNA into respiratory epithelial cells of the maxillary sinus of 10 CF patients. STUDY DESIGN: A prospective, randomized, unblinded, dose-escalation, within-subjects, phase I clinical trial of AAV-CFTR was conducted. PATIENTS: Ten patients with previous bilateral maxillary antrostomies were treated. MAIN OUTCOME MEASURES: Safety, gene transfer as measured by semiquantitative polymerase chain reaction (PCR), and sinus transepithelial potential difference (TEPD) were measured. RESULTS: The highest level of gene transfer was observed in the range of 0.1-1 AAV-CFTR vector copy per cell in biopsy specimens obtained 2 weeks after treatment. When tested, persistence was observed in one patient for 41 days and in another for 10 weeks. Dose-dependent changes in TEPD responses to pharmacologic intervention were observed following treatments. Little or no inflammatory or immune responses were observed. CONCLUSION: AAV-CFTR administration to the maxillary sinus results in successful, dose-dependent gene transfer to the maxillary sinus and alterations in sinus TEPD suggestive of a functional effect, with little or no cytopathic or host immune response. Further study is warranted for AAV vectors as they may prove useful for CFTR gene transfer and other in vivo gene transfer therapies. A prospective, randomized, double-blind, placebo-controlled, within-subjects, phase II clinical trial of the effect AAV-CFTR on clinical recurrence of sinusitis will determine the clinical efficacy of AAV gene therapy for CF.

[Evaluation of intramyocardial coronary flow velocity pattern before and after surgical repair of Bland-White-Garland syndrome by pulsed Doppler echocardiography].

Anomalous origin of the left main coronary artery from the pulmonary artery (Bland-White-Garland syndrome) is a rare congenital anomaly. Intramyocardial coronary flow dynamics by pulsed Doppler echocardiography were studied in three patients with this syndrome who underwent surgical repair by Hamilton's method. Before surgery, the intramyocardial flow at the ventricular septum showed a retrograde velocity pattern which had two peaks in systole and diastole in all patients. After surgery, two patients with successful repair showed a biphasic intramyocardial flow pattern which consisted of retrograde and antegrade flows in systole and diastole, respectively. In contrast, one patient who had a residual shunt between the left coronary artery and the pulmonary artery showed a biphasic pattern which had antegrade flow in systole and retrograde flow in diastole. These results may suggest that the evaluation of postoperative intramyocardial coronary flow velocity pattern by pulsed Doppler echocardiography is useful for detecting a residual shunt after surgical repair of Bland-White-Garland syndrome.

Calcium- and CaMKII-dependent chloride secretion induced by the microsomal Ca(2+)-ATPase inhibitor 2,5-di-(tert-butyl)-1,4-hydroquinone in cystic fibrosis pancreatic epithelial cells.

Microsomal Ca(2+)-ATPase inhibitors such as thapsigargin (THG), cyclopiazonic acid (CPA) and 2,5-di-(tert-butyl)-1,4-hydroquinone (DBHQ) have been shown to inhibit Ca2+ reuptake by the intracellular stores and increase cytosolic free Ca2+ ([Ca2+]i). DBHQ is a commercially available non-toxic synthetic compound chemically unrelated to THG and CPA. In this study, we tested the feasibility of utilizing DBHQ to improve Cl- secretion via the Ca(2+)-dependent pathway, in the cystic fibrosis (CF)-derived pancreatic epithelial cell line CFPAC-1. DBHQ stimulated 125I efflux and mobilized intracellular free Ca2+ in a dose-dependent manner. The maximal effects were seen at concentrations of 25-50 microM. DBHQ (25 microM) caused a short-term rise in [Ca2+]i in the absence of ambient Ca2+, and a sustained elevation of [Ca2+]i in cell monolayers bathed in the efflux solution (1.2 mM Ca2+), which was largely attenuated by Ni2+ (5 mM). Bath-application of DBHQ induced an outwardly-rectifying whole-cell Cl- current, which was abolished by pipette addition of BAPTA (5 mM) or CaMK [273-302] (20 microM), an inhibitory peptide of multifunctional Ca2+/calmodulin-dependent protein kinase (CaMKII). Pretreatment of monolayers of CFPAC-1 cells with DBHQ for 4-5 min significantly increased the Ca(2+)-independent or autonomous activity of CaMKII assayed in the cell homogenates. Thus, DBHQ appears to enhance Cl- channel activity via a Ca(2+)-dependent mechanism involving CaMKII. Pretreatment of CFPAC-1 cells with up to 50 microM DBHQ for 6 h did not cause any detectable change in cell viability and did not significantly affect the cell proliferation rate. These results suggest that appropriate selective microsomal Ca(2+)-ATPase inhibitors may be therapeutically useful in improving Cl- secretion in CF epithelial cells.

Activation of CFTR chloride current by nitric oxide in human T lymphocytes.

Nitric oxide, which is produced by cytokine-activated mononuclear cells, is thought to play an important role in inflammation and immunity. While the function of nitric oxide as a direct cytotoxic effector molecule is well established, its function as a transducer molecule in immune cells is not. By use of whole-cell patch clamp recordings, we show that nitric oxide activates cystic fibrosis transmembrane conductance regulator CI- currents in normal human cloned T cells by a cGMP-dependent mechanism. This pathway is defective in cystic fibrosis-derived human cloned T cells. These findings not only delineate a novel transduction mechanism for nitric oxide but also support the hypothesis that an intrinsic immune defect may exist in cystic fibrosis.

Volume-activated chloride current is not related to P-glycoprotein overexpression.

It has been suggested that P-glycoprotein (P-gp), an ATP-dependent transporter responsible for classical multidrug resistance, is also a volume-regulated chloride channel. We reexamined this hypothesis by use of whole-cell patch clamp recordings of three matched pairs of cell lines, which were either drug-sensitive or drug-resistant due to P-gp overexpression. We demonstrate here that volume-regulated chloride-selective currents can be induced in cells with or without P-gp expression. Overexpression of either P-gp or cystic fibrosis transmembrane conductance regulator, the protein product of the CF gene and another member of the ATP-dependent transporters, is associated with a hypotonicity-induced, rapid onset, transient current prior to onset of the volume-sensitive chloride-selective current, an apparent nonspecific effect related to the overexpression of an integral membrane protein. These results suggest that there is no relationship between P-gp and the chloride channel activated by cell swelling.

A case of myelodysplastic syndrome progressing to acute myelocytic leukemia in which adult-onset Still's disease had occurred 6 years before.

A patient with adult-onset Still's disease who presented with myelodysplastic syndrome (MDS) after a course of 6 years is reported. To our knowledge, this is the first such reported case. The patient died of acute myelocytic leukemia. The possibility that cyclosporine contributed to the onset of MDS is discussed.

[Reverse passive hemagglutination assay for human chorionic gonadotropin in urine using monoclonal antibody].

Aiming to find a urinary hCG immuno-assay which is specific, sensitive and easy to perform, a reverse passive hemagglutination reaction was studied by using sheep red blood cells (SRBC) coupled with monoclonal antibodies (Mab) to hCG. Three Mabs (5D4, 6E4, 2F8) with different specialty were used for the study. Mab 5D4 reacted to hCG, hCG-beta, and LH but not to hCG-alpha. Mab 6E4 reacted to hCG, hCG-alpha and LH, but not to hCG-beta. Mab 2F8 reacted to hCG but not to hCG-alpha, hCG-beta, or LH. All three Mabs were IgG1. SRBC were treated with glutaraldehyde and then with tannic acid. These treated SRBC were coupled with IgG(2mg/ml) of each anti hCG-Mab. For assays, 30 microliters of 1:1 mixtures of two different Mab-coupled SRBC and 30 microliters of standard hCG or urine samples were mixed in wells of microtiter plates and reacted for 60 min at room temperature. Among three different combinations, the couple 5D4-SRBC and 2F8-SRBC were most sensitive and specific for hCG assays and the minimum amount of hCG and LH detected in this combination assays was 12.5 mIU/ml and 800 mIU/ml, respectively. Some clinical data obtained by applying this assay were presented.

[Bactericidal activity of aspoxicillin in an in vitro model simulating human serum levels].

Bactericidal activities of aspoxicillin (ASPC) against E. coli (2 strains) and K. pneumoniae (1 strain) were compared with those of piperacillin (PIPC) using in vitro kinetic models simulating human serum levels. In the model of intravenous injection, both drugs exhibited bactericidal action against the strains of E. coli. The activity of ASPC was found to superior to PIPC and ASPC could decrease viable cell counts from 10(7) cells/ml to 10(8) cells/ml. On the other hand, the bactericidal activity of ASPC against K. pneumoniae was weaker than that of PIPC. In the model of intravenous drip infusion, ASPC showed a high level of bactericidal activity comparable to that observed in the intravenous model against E. coli. Interestingly, the bactericidal activity of ASPC against K. pneumoniae in this model was similar to that of PIPC, though the MIC value of ASPC was higher than that of PIPC. In the intravenous model, the effects of ASPC and PIPC on the morphology of E. coli KC-14 were examined with a phase contrast microscope. Exposure to PIPC caused only an elongation of the cells, but the treatment with ASPC resulted in the formation of spheroplast-like structure of the cells, which were finally subjected to bacteriolysis.