Establishment of large cell lung cancer cell lines secreting hematopoietic factors inducing leukocytosis and thrombocytosis

We have established cell lines from a large cell carcinoma of the lung accompanied by marked granulocytosis and thrombocytosis, and have analyzed the factors with colony stimulating factor (CSF) activity produced by them. Analysis of the CSF activity present in the culture medium of the established cell lines demonstrated growth-stimulating activity on CMK cells, a human megakaryoblastic cell line and mouse bone marrow cells. A neutralization test with antibodies against G-, M- and GM-CSF indicated the stimulation for the proliferation of CMK and mouse bone marrow cells to be mediated partially by the CSFs. Furthermore, the measurement of GM-CSF and interleukin(IL)6 by enzyme-linked immunosorbent assay (ELISA) and northern blotting analysis indicated productions of G-, GM- and M-CSF and of IL6 from the cell lines but failed to exhibit IL3 gene expression. It is suggested that the cell lines could be of use in the study of CSFs and, also, that lymphokines act on leukocyte and platelet progenitor cells.

Study of mechanisms of electric field-induced DNA transfection. IV. Effects of DNA topology on cell uptake and transfection efficiency

Electric parameters and solvent conditions are known to influence the efficiency of DNA transfection of cells by a pulsed electric field (PEF). A previous study (Neumann, E., M. Schaefer-Ridder, Y. Wang, and P. H. Hofschneider. 1982. EMBO (Eur. Mol. Biol. Organ.) J. 1:841-845) has indicated that DNA topology is also an important determinant. We report an investigation of the PEF induced uptake, stability, and expression of three different topological isomers, circular supercoiled (scDNA), circular relaxed (crDNA), and linearized (lnDNA) forms of the plasmid pBR322, by Escherichia coli strain JM105. Monomeric pBR322 prepared by the electroelution from an agarose gel was in the supercoiled form. Treatment of the scDNA with wheat germ topoisomerase I removed the superhelicity and the DNA assumed the relaxed circular form. Treatment of scDNA by a restriction endonuclease, EcoRI or Hind III, linearized the DNA. The MgCl2-dependent bindings of all three forms of DNA to the cell surface were indistinguishable. So was the PEF induced cell uptake. In contrast, the transfection efficiency (TE) for the scDNA and the crDNA were high (approximately 2 x 10(8) micrograms-1 DNA at neutral pH), whereas that for the lnDNA was approximately five orders of magnitude lower (less than 1 x 10(3) micrograms-1 DNA). Analysis by agarose gel electrophoresis indicated that the PEF loaded ln DNA was degraded by the host cell within 3 h. However, the loaded scDNA and the crDNA were stable and expressed in the cytoplasm. We conclude that first, the PEF induced DNA entry into E. coli did not depend on the topology of the DNA. As cellular uptake of DNA also correlated with the surface binding, these data support electrophoresis of surface bound DNA as the dominating mechanism for the DNA entry. Second, the variations of TE for different topological forms of DNA reflected their relative stability in the host cells. Third, since the loaded DNA could be either rapidly degraded by the host enzyme or expressed, they were unlikely coated with a layer of protective lipid membrane. Thus, PEF induced cellular uptake of DNA is unlikely by the endocytotic mechanisms as was reported previously for the liposomes (Chernomordik, L. V., A. V. Sokolov, and V. G. Budker. 1990.Biochim. Biophys. Acta. 1024:179-183).

Escherichia coli ribonucleotide reductase expression is cell cycle regulated

The expression of the genes encoding ribonucleotide reductase in Escherichia coli was investigated in cultures synchronized by obtaining the smallest cells in a population after sucrose gradient centrifugation. Specific activity of ribonucleotide reductase and DNA initiation were found to increase in parallel, periodically as a function of the cell cycle. The expression of nrd was also determined in cells synchronized by periodic repeated doubling in a phosphate limited medium. Antibodies directed against the B2 subunit of ribonucleotide reductase were raised in a rabbit and purified. Immunoprecipitation of the B2 subunit and RNA-DNA dot blot hybridization assays were developed and employed to determine the expression of ribonucleotide reductase translational and transcriptional products during the cell cycle. Both of nrd-mRNA and B2 subunit expression were found to increase each generation at approximately the same time DNA synthesis was initiated and then to decrease back to the basal level shortly after DNA initiation. These results provided evidence of cell cycle dependent regulation of ribonucleotide reductase in E. coli. When the upstream regulatory region of nrd was fused to a promoterless lacZ gene on a single copy plasmid, lac-mRNA and beta-galactosidase were found to be synthesized in parallel to nrd expression from the chromosomal operon. When nrd sequences surrounding the promoter were removed from this construct, lac-mRNA and beta-galactosidase synthesis were no longer cell cycle regulated.

The frequency of alpha 2-adrenoceptor restriction fragment length polymorphisms in normotensive and hypertensive humans

OBJECTIVE

To examine the frequency of distribution of allelic polymorphisms of the alpha 2-adrenoceptor gene in normotensive and hypertensive humans.

DESIGN

The frequency of alpha 2-adrenoceptor genotypes was compared in the two groups using the chi 2-test.

SETTING

The Midwest Hypertension Research Center Outpatient Clinic of Creighton University School of Medicine.

STUDY PARTICIPANTS

History was taken from and physical examination performed on each of the 60 hypertensive and 47 normotensive adults.

METHODS

DNA was extracted from leukocytes from each participants. Twenty restriction endonucleases were used and one restriction fragment length polymorphism (RFLP) was found using a 950-bp restriction fragment from the coding region of the human platelet alpha 2-adrenoceptor gene (ADRA2R) and Bsu36I restriction endonuclease. This probe and Bsu36I restriction endonuclease, in addition to another restriction endonuclease (Dra I), were then used in the study.

RESULTS

Three genotype patterns were found. Homozygotes for the Bsu36I RFLP have either a unique 12-kb or a unique 5.8-kb band. Heterozygotes have both bands. The frequency of this alpha 2-adrenoceptor RFLP was calculated. In hypertensives the frequencies of the 12- and 5.8-kb alleles were 0.52 and 0.48, compared with 0.45 and 0.55, respectively, in normotensive, a difference that was not statistically significant.

CONCLUSIONS

The frequency of the Bsu36I RFLP involving an alpha 2-adrenoceptor gene in hypertensives did not differ significantly from that in normotensives. A genetic linkage study is now under way to test for an association of the Bsu36I RFLP of the alpha 2-adrenoceptor gene with essential hypertension in families.

Northern blot and ribonuclease protection study of alpha 2-adrenoceptor subtypes in cultured cell lines

Northern blot and ribonuclease protection assay were used to identify alpha 2-adrenoceptor subtypes in human colonic adenocarcinoma (HT29), neuroblastoma x glioma rat-mouse hybrid NG108-15 (NG108) and opossum kidney (OK) cell lines. Radioligand binding studies showed that the alpha 2-adrenoceptor expressed in HT29, NG108 and OK cells represent the pharmacological alpha 2A, alpha 2B and alpha 2C subtypes respectively. In our Northern blot analysis, hybridization of poly(A)+ RNA from HT29, NG108 and OK cells with human kidney alpha 2-adrenoceptor cDNA probe (alpha 2-C4) identified a single band of 4.4, 4.2 and 4.4 kb respectively in each cell line. Hybridization with a human platelet alpha 2-adrenoceptor genomic probe (alpha 2-C10) resulted in two bands for HT29 cells with the size of 4.4 kb and 3.9 kb. No bands were seen for HT29, NG108 and OK cells when hybridized with a third alpha 2-adrenoceptor human genomic DNA probe which is localized in chromosome 2 (alpha 2-C2). For the HT29 cells, the 3.9 kb band was seen only when using the alpha 2-C10 probe. Thus, this band probably represents alpha 2-C10 mRNA. To further characterize the alpha 2-adrenoceptor mRNA expressed in HT29, NG108 and OK cells, the sensitive ribonuclease protection assay was performed. A single band about 900 bp was protected when the poly(A)+ RNA from NG108 and OK cells was hybridized with an alpha 2-C4 RNA probe and digested with RNAases. Hybridization of mRNA from HT29 cells with alpha 2-C10 RNA probe and digestion with RNAases protected a 500 bp fragment.(ABSTRACT TRUNCATED AT 250 WORDS)

Stimulation of prostaglandin production in rat thymic epithelial cells by protein kinase C mediated activation of phospholipase A2

Tumor promoter (phorbol-12-myristate-13-acetate:PMA) stimulates the production of prostaglandin E2 (PGE2) in a dose- and time-dependent manner in cloned rat thymic epithelial cells, TEA3A1. This stimulation of PGE2 production by PMA was blocked by pretreatment of cells with protein kinase C (PKC) inhibitor staurosporin and was abolished in PKC down modulated cells. PMA treatment significantly stimulated the release of arachidonic acid from the cells, but had no effect on arachidonic acid incorporation and on cyclooxygenase enzymatic activity of the cells. These results indicate that PMA stimulates PGE2 production through PKC mediated activation of phospholipase A2 (PLA2) in thymic epithelial cells.

Chromosome analysis in spontaneous pregnancy loss: use of placental villus mesodermal core cell cultures

Culture of placental villus mesodermal core cells, a method developed for chorionic villus sampling, was used for cytogenetic analysis in 168 spontaneous pregnancy losses. Successful karyotype results were obtained in 72% of cases and 87.5% of cases in which placental tissue was available. Culture of placental villus mesodermal core cells is useful in the evaluation of spontaneous pregnancy loss, particularly when tissues of direct fetal origin are unavailable or unsuitable for culture. Details of culture and specimen handling techniques are provided.

Induction of cytochrome P450 isozymes in human amnion FL cells and its application to the biological detection of mutagens

Using AHH, EROD, ECOD and APND as marker enzymes and 3-MC, beta-NF, NE and PB as inducers, inducible cytP450 IA and IIB gene expression was demonstrated in the human amnion FL cell line; these cells possess a broad spectrum of drug-metabolizing enzymes. Maximum induction was observed following co-treatment with 3-MC and NE. Both constitutive and induced AHH were proved to have the characteristics of cytP448-dependent mixed-function oxygenases. Induced cytP450 isozyme activity remained at a high level for 24-36 h after removal of the inducer. The induced FL cells were demonstrated to activate common promutagens/procarcinogens in UDS and ADPRT-mediated decrease of NAD content assay systems. This new design can be used as a simplified mutagen screening system: no supplemental liver microsomal activation system is needed.

Characterization of prazosin-sensitive alpha 2 B-adrenoceptors expressed by cultured rat IMCD cells

alpha 2-Adrenoceptor subtype expression was investigated in cultured rat inner medullary collecting duct (IMCD) cells using radioligand binding studies, Northern blot analysis, and adenosine 3',5'-cyclic monophosphate (cAMP) assays. [3H]rauwolscine bound to a single class of alpha 2-adrenoceptors with high affinity [Kd = 1.7 +/- 0.3 nM, maximum binding (Bmax) = 45.2 +/- 10.8 fmol/mg protein]. alpha 2-Adrenoceptor ligands inhibited [3H]rauwolscine binding with a rank order of potency characteristic of interaction with the alpha 2B-adrenoceptor [inhibitory constant (Ki) values (in nM) rauwolscine (1.95) greater than ARC-239 (8.52) greater than prazosin (237) greater than oxymetazoline (30,000)]. Northern blot analysis was performed using poly(A)+ RNA isolated from 90% confluent rat IMCD cells and probes derived from alpha 2-adrenoceptor DNA sequences from the rat nonglycosylated alpha 2B-adrenoceptor and the human alpha 2A-adrenoceptor. The alpha 2B probe hybridized to a 4.2-kb band under high stringency conditions, but the alpha 2A-adrenoceptor probe did not hybridize to this band. In functional studies, the full alpha 2-adrenoceptor agonists epinephrine and UK-14,304 potently inhibited vasopressin-stimulated cAMP accumulation by 50 to 70% [half-maximal response (EC50) (in nM) epinephrine = 11.2, UK-14,304 = 6.4]. Guanabenz and clonidine were partial agonists, inhibiting cAMP accumulation by 30 to 40% and were less potent than the full agonists [EC50 (in nM) 56.0 guanabenz and 94.5 clonidine]. Epinephrine-induced inhibition of cAMP accumulation was blocked by rauwolscine, prazosin, and ARC-239 but not by the alpha 1-adrenoceptor antagonist corynanthine. We conclude that rat IMCD cells in primary culture express functional alpha 2-adrenoceptors of the alpha 2B-subtype.

Vergence control of central and peripheral disparities

The results of previous studies using either small or large target configurations suggest that open-loop (OL) vergence response dynamics may depend on the peripheral extent of the target. To investigate systemically the effect of peripheral target extent on dynamic vergence control, OL vergence responses to central, peripheral, and central-plus-peripheral targets were recorded. Open-loop disparity stimuli included steps, ramps, and sinusoids. It was found that the OL step and ramp responses to the central target were more rapid and exhibited significantly more step and multiple-step movements than those for either the peripheral or the central-plus-peripheral targets. During OL ramp stimulation, the maximum disparity for which tracking could be maintained was largest for the peripheral target. Sinusoidal responses showed the greatest gain for the central target. For all three types of stimuli, responses to the central-plus-peripheral target showed characteristics that were somewhat between those for the central and the peripheral targets. These results resolve some previously conflicting findings about open-loop vergence dynamics and suggest that large peripheral disparity stimulation initiates slow fusion of a visual scene, whereas small central disparity stimulation produces more rapid movements for precise binocular tracking of targets moving in depth.

Effects of IL-5, granulocyte/macrophage colony-stimulating factor (GM-CSF) and IL-3 on the survival of human blood eosinophils in vitro

The mechanisms that could affect the lifespan of eosinophils after they have left the bone marrow, and their capacity to respond to activation factors were studied by examining the effects of IL-5, GM-CSF and IL-3 on purified human blood eosinophils in culture. All three cytokines prolonged the lifespan of the majority of blood eosinophils. This effect was dose-dependent: IL-5 greater than GM-CSF greater than IL-3. Light density eosinophils from most patients had a longer lifespan in culture than did normal density eosinophils, with or without the three cytokines. Eosinophil death in the absence of these cytokines occurred by apoptosis. Eosinophils from two patients did not survive when cultured with IL-5, although they survived in the presence of IL-3 or GM-CSF. IL-5, GM-CSF and IL-3 induced the expression of the activation epitope on the eosinophil ribonucleases recognized by monoclonal antibody EG2. We conclude that small amounts of IL-5, GM-CSF and IL-3 prevented programmed cell death in human blood eosinophils and induced the expression of the activation forms of eosinophil ribonucleases. We suggest that differences in the capacity of normal and light density eosinophils to survive in culture, and in the ability of eosinophils from some patients to respond to IL-5 could account for variations in the severity of disease seen in patients with persistent eosinophilia.

Sex chromosome marker: clinical significance and DNA characterization

Two patients are described with a virtually identical marker sex chromosome that was so small as to defy classification by conventional cytogenetic studies. DNA hybridization with Y probes allows classification into Y or non-Y, and in situ hybridization with X centromere specific sequences, into X or non-X. One patient was proven to have a Y fragment, and the second, an X fragment. DNA characterization is important since prognosis and clinical management depends on proper identification of the small marker sex chromosome.

Suppression of sensitivity to change in target disparity during vergence eye movements

It has been demonstrated recently in human psychophysical experiments that sensitivity to surround displacement is suppressed during convergence eye movements. To determine whether sensitivity to changes in target disparity is also reduced, responses to test disparities that were superimposed on standard 4 degrees step disparities were investigated. The test disparities consisted of brief (20 ms) positive and negative pulses as well as steps (in the range of +/- 0.6 degrees). A two-alternative forced-choice procedure was used in which the test disparity was presented in either the first or the second portion of a trial. The results showed that suppression of both test pulse and step disparities began before the start of the convergence movement and continued during the movement. Maximum suppression was about 0.50 to 0.85 log units and occurred between 150 ms before to 50 ms after convergence onset. The differences in sensitivity curves for pulse and step stimuli suggest the presence of different central and peripheral neural factors during vergence eye movements.

[Toxic effects of moniliformin on heart function in rats]

The present study was carried out on intact heart of rat to determine the myocardial toxicity of moniliformin (MLFN) in vitro and in vivo Perfusion of MLFN 0.1 mumol/L in isolated heart decreased myocardial contractile force by 52 +/- 17%, and the effect was not reversible after the infusion of MLFN had stopped. The intravenous LD50 of MLFN in mice was found to be 17.51 +/- 1.64 mg/kg. Intravenous injection of MLFN at 1/4 LD50 markedly inhibited cardiac hemodynamic variables relative to myocardial contractile function. Particularly, it decreased left ventricular pressure development (dP/dt max) by 52 +/- 6%, and induced ventricular arrhythmia. The results showed that MLFN severely damaged the heart function of healthy rats.

[Effects of 2-[p-(dimethylamino)styryl] pyridine methiodide on conduction and refractory period of atrioventricular node in rat]

The effects of 2-[p-(dimethylamino)styryl] pyridine methiodide (DSPM) on rat ECG and HBE were studied. The P-R and R-R intervals of ECG were lengthened 40.3% and 115.4% respectively, after iv injection of DSPM 2 mg/kg. DSPM (1.5 and 2 mg/kg) affected the A-H interval in a dose-dependent manner with no change in the H-V interval of HBE. DSPM 0.5 mumol/L lengthened the A-H interval of isolated perfused hearts in frequency-dependent manner, with greater prolongation at higher frequency. The effect of verapamil on the A-H interval was less than that of DSPM. Propranolol had no effect on the frequency-dependent delay of atrioventricular node. DSPM 0.5 mumol/L lengthened the functional and effective refractory periods of atrioventricular node by 26.8% and 31% respectively. These phenomena support that DSPM may be a calcium antagonist.

Thymocytes stimulate metabolism of arachidonic acid in rat thymic epithelial cells

Arachidonic acid metabolites play an important role in the development of T cells in the thymus. In the normal animal, prostaglandin levels in the thymus are significantly higher than in plasma. Herein, we have studied the regulation of arachidonic acid metabolism using the thymic endocrine epithelial cell line, TEA3A1, and thymocytes. We have found that TEA3A1 cells, but not thymocytes, produced prostaglandins and thromboxanes. We have also found that thymocytes could stimulate the production of arachidonic acid metabolites in TEA3A1 cells when both cells were cocultured. The strongest stimulation was observed when TEA3A1 cells were cocultured with thymocyte subpopulations either negative for OX8 or W3/25 functional surface markers (either double-negative or single-positive thymocytes). Furthermore, cell-cell contact seems to be absolutely required for the activation of arachidonic acid metabolism in TEA3A1 cells. The study presented here describes the existence of a novel regulatory mechanism of arachidonic acid metabolism which may play an important role in the development of T cells in the thymus.

[An experimental study of basement membrane of the muscle grafts in the peripheral nerves]

The suitability of muscle basement membrane tubes as alternative to autogenous nerve grafting was appraised by comparing the nerve regeneration process in muscle basement membrane tube grafts used to bridge gaps in peripheral nerves with that in nerve grafts. The results revealed that nerve fibres grew through the muscle basement membrane tubes spanning a 2 cm gap and reinnervated end organ, at 20 weeks after operation, the nerve function recovered satisfactorily. However, the toe-spreading function, MCV and the amplitude of MAP on the muscle basement membrane tube grafting sides were not as good as on the nerve grafting sides, the axon diameter and degree of remyelination for the former also inferior to the latter. As time elapsed postoperatively, the difference between two kinds of grafts showed a tendency to diminish by all criteria used in this study. It imply that muscle basement membrane tube graft is a promising alternative to nerve grafting.