Establishment and characterization of human neuroblastoma cell line (HSNB)

We cultured an aspiration fluid of the sternal bone marrow of the patient having adrenal neuroblastoma and established a neuroblastoma cell line (HSNB). The HSNB line has the following biological properties. 1. They are small round in shape and proliferate in flotation while forming cell aggregate, and often they attach the bottom of plastic dish and process the nerve-like fibers. A rough-endoplasmic reticulum are poorly developed, however, a lot of free ribosomes are scattered in the cytoplasm. In the peripheral area of the cells, small spherical secretory granules (60-140 nm in diameter) are existed. One characteristic of this cell is existence of microtubules in the cell-projections. 2. They show a stable growth and the doubling time is about 50 hours. 3. Their chromosome number varied widely and the mode is 46. The double minute chromosomes were present in 50% of cells. 4. When they are transplanted in the cheek pouch of hamster, they produced the neuroblastoma. 5. They produce neuron specific enolase. 6. N-myc gene was amplified ca 250 folds.     

Hyperthermostable endoglucanase from Pyrococcus horikoshii.

An endoglucanase homolog from the hyperthermophilic archaeon Pyrococcus horikoshii was expressed in Escherichia coli, and its enzymatic characteristics were examined. The expressed protein was a hyperthermostable endoglucanase which hydrolyzes celluloses, including Avicel and carboxymethyl cellulose, as well as beta-glucose oligomers. This enzyme is the first endoglucanase belonging to glycosidase family 5 found from Pyrococcus species and is also the first hyperthermostable endoglucanase to which celluloses are the best substrates. This enzyme is expected to be useful for industrial hydrolysis of cellulose at high temperatures, particularly in biopolishing of cotton products.     

Pyrindicin,a New Alkaloid from a Streptomyces Strain

In the course of our examination for the alkaloid productivities of Streptomyces strains, Streptomyces sp. NA–15 was found to produce a new alkaloid, pyrindicin, in the culture medium. The strain NA–15 was found to be a variant of Streptomyces griseoflavus and was designated as S. griseoflavus var. pyr indie us nov. var.

After the culture conditions for pyrindicin production were studied, pyrindicin was obtained as its hydrochloride (mp 145°C, decomp.) from the cultured broth. The compound was shown to possess weak antimicrobial and several pharmacological activities. The LD₅₀ of the hydrochloride (ip, in mice) was 87 mg/kg.     

Expression of normal cellular prion protein (PrP(c)) on T lymphocytes and the effect of copper ion: Analysis by wild-type and prion protein gene-deficient mice

The purpose of this report was to determine the effect of prion protein (PrP) gene disruption on T lymphocyte function. Previous studies have suggested that normal cellular prion protein (PrP(c)) binds to copper and Cu(2+) is essential for interleukin-2 (IL-2) mRNA synthesis. In this study, IL-2 mRNA levels in a copper-deficient condition were investigated using T lymphocytes from prion protein gene-deficient (PrP(0/0)) and wild-type mice. Results showed that Cu(2+) deficiency had no effect on PrP(c) expression in Con A-activated splenocytes. However, a delay in IL-2 gene expression was observed in PrP(0/0) mouse T lymphocyte cultures using Con A and Cu(2+)-chelator. These results suggest that PrP(c) expression may play an important role in rapid Cu(2+) transfer in T lymphocytes. The rapid transfer of Cu(2+) in murine T lymphocytes could be one of the normal functions of PrP(c).     

Establishment and characterization of a new human glioblastoma cells line, NYGM

A cell line designated NYGM was established from a human cerebral glioblastoma multiforme (GBM) obtained from a 75-year-old Japanese woman. The cell line has grown slowly without interruption and has been propagated continuously by serial passages (more than 80 passage) during the past 3 years. The cultured cells were fusiform or polyhedral in shape. The population doubling time was 24 hours. The chromosomal number varied between 77 and 88, with modal chromosomal number of 84. NYGM cells concomitantly expressed MET receptor tyrosine kinase (a product of c-met protooncogene) and its ligand HGF/SF (hepatocyte growth factor/scatter factor), as well as HGF activator and HGF activator inhibitors. The cells might be useful for the study of pericellular regulation of HGF/SF-MET signaling and HGF activation of GBM cells.     

Efficacy of Recombinant Canine Distemper Virus Expressing Leishmania Antigen against Leishmania Challenge in Dogs

Canine distemper virus (CDV) vaccination confers long-term protection against CDV reinfection. To investigate the utility of CDV as a polyvalent vaccine vector for Leishmania, we generated recombinant CDVs, based on an avirulent Yanaka strain, that expressed Leishmania antigens: LACK, TSA, or LmSTI1 (rCDV–LACK, rCDV–TSA, and rCDV–LmSTI1, respectively). Dogs immunized with rCDV-LACK were protected against challenge with lethal doses of virulent CDV, in the same way as the parental Yanaka strain. To evaluate the protective effects of the recombinant CDVs against cutaneous leishmaniasis in dogs, dogs were immunized with one recombinant CDV or a cocktail of three recombinant CDVs, before intradermal challenge (in the ears) with infective-stage promastigotes of Leishmania major. Unvaccinated dogs showed increased nodules with ulcer formation after 3 weeks, whereas dogs immunized with rCDV–LACK showed markedly smaller nodules without ulceration. Although the rCDV–TSA- and rCDV–LmSTI1-immunized dogs showed little protection against L. major, the cocktail of three recombinant CDVs more effectively suppressed the progression of nodule formation than immunization with rCDV–LACK alone. These results indicate that recombinant CDV is suitable for use as a polyvalent live attenuated vaccine for protection against both CDV and L. major infections in dogs.     

Diagnostic Value of the Amplicor PCR Assay for Initial Diagnosis and Assessment of Treatment Response for Pulmonary Tuberculosis

We evaluated the Amplicor PCR assay as an initial diagnostic tool on the basis of clinical diagnosis, and assessed this assay as a follow-up test for patients with pulmonary tuberculosis during chemotherapy. Of the 208 specimens from 155 patients who were bacteriologically and/or clinically diagnosed with active tuberculosis before chemotherapy, 144 were Amplicor PCR-positive (sensitivity, 69.2%), which was equal to the results of culturing. Among 89 specimens which showed positive results by smear and culturing, the Amplicor PCR assay detected 87 (97.8%), whereas among 55 specimens which showed smear-negative but culture-positive results, the Amplicor PCR assay detected 46 (83.6%)(P = 0.003). No false positive results were found in the two systems (specificity, 100%, 120/120). The Amplicor PCR assay was also evaluated as a follow-up test using 926 specimens from 207 patients receiving active tuberculosis chemotherapy. Among 433 specimens which showed Amplicor-PCR positive, 222 (51.3%) were culture-negative. On the other hand, among 233 culture-positive specimens, only 12 (5.2%) were Amplicor PCR-negative. Therefore, this assay is useful for the rapid diagnosis of tuberculosis. The duration of Amplicor PCR-positive after culture-negative conversion was significantly associated with the presence of cavitary lesion, smear-positive specimens before treatment, and smear-positive specimens with negative cultures during chemotherapy.