13C-NMR spectral analysis of the structures of mouse immunoglobulin G1 carrying allotypes a and j

A novel 13C nuclear magnetic resonance (NMR) method is described for the detection of subtle structural differences between mouse immunoglobulins carrying different allotypes. Fc fragments of mouse IgG1 antibodies carrying allotypes a and j have been selectively labeled with [1-13C]methionine. 13C-NMR spectra have shown that the microenvironment around Met-398 is significantly different for the two kinds of allotypes. Peptide mapping and amino acid sequence analyses have revealed that Val-406 of IgG1 carrying allotype a is substituted for Ile in the case of allotype j. X-ray crystallographic data indicate that Met-398 is in close spatial proximity to Val (Ile)-406. We therefore conclude that the 13C-NMR method can provide us with a novel spectroscopic probe for the structural characterization of allotypic markers.

Binding of monoclonal antibody specific for domain Ia/II of Pseudomonas aeruginosa exotoxin A at pH 4 strongly neutralizes exotoxin A-induced cytotoxicity in cell culture and in vivo

Mouse monoclonal antibodies (MAbs) against Pseudomonas aeruginosa exotoxin A (Ex-A) were established, and 4 of 20 MAbs were extensively studied for analysis of the structure-function relationship of Ex-A. IN vivo experiments demonstrated that MAb Ex-3C7 protected mice either injected with Ex-A or infected with Ex-A-producing P. aeruginosa from death caused by Ex-A at the highest rate, followed by MAbs Ex-4F2 and Ex-8H5, in that order. MAb Ex-2A10 failed to rescue the mice. MAb Ex-3C7 (immunoglobulin G1 [IgG1]) inhibited incorporation of Ex-A into target cells and strongly neutralized cytotoxicity in cell culture but did not inhibit an enzymatic activity of Ex-A, ADP-ribosyltransferase, at all. The MAb also bound Ex-A, even at a low pH of 4, and recognized amino acid residues 241 to 297 (domain Ia/II), suggesting that MAb Ex-3C7 can interfere with the conformational change and/or processing of Ex-A by keeping a complex of Ex-A and antibody stable at low pH in the phagolysosome. MAb Ex-4F2 (IgG1), which recognizes residues 550 to 590 (domain III), strongly inhibited Ex-A incorporation and neutralized cytotoxicity in cell culture but only weakly inhibited ADP-ribosyltransferase. MAb Ex-8H5 (IgG1), which recognizes residues 591 to 613 (domain III), also inhibited cytotoxicity in cell culture, but weakly. In contrast to the above three MAbs, MAb Ex-2A10 (IgG2b) greatly inhibited ADP-ribosyltransferase but showed no inhibition of Ex-A incorporation and no neutralizing activity against cell toxicity. A line of evidence indicates that (i) domain Ia/II plays an important role in the pathogenesis of Ex-A and (ii) MAbs that inhibit an intracellular postbinding process, such as conformational change, processing, and translocation of Ex-A in target cells, can display potent inhibitory activity against cytotoxicity in vivo, as well as in cell culture, and would be a good candidate for therapy of pseudomonal infections.

Functional analysis of mononuclear cells infiltrating into tumors. VI. The effect of lymphocyte chemotactic factors on lymphocyte adhesion to endothelial cells

We have analyzed mechanisms controlling infiltration of T lymphocytes into tumor tissues. A lymphocyte chemotactic factor-b (LMF-b) produced by tumor infiltrating CD4+ T lymphocytes was purified. LMB-b was specifically chemotactic for CD8+ T lymphocyte. Furthermore, LMF-b augmented lymphocyte adhesion to high endothelial venule (HEV) cells. The binding of CD8+ T cells to HEV cells was specifically augmented by LMF-b. The LMF-b primarily acted on T lymphocytes, whereas tumor necrosis factor as well as IFN-gamma acted on HEV cells or fibroblast cells. The binding of lymphocytes to fibroblast cell line was not augmented by LMF-b. The augmentation of lymphocyte adhesion to endothelial cells by LMF-b was mediated by the lymphocyte function associated antigen-1/intercellular adhesion molecule (LFA-1/ICAM) pathway, the CD2/LFA-3 pathway, and the very late antigen-4/culture supernatant-1 (VLA-4/CS-1) pathway.

A new DNA profiling system for cell line identification for use in cell banks in Japan

Using the polymorphic DNA probes, ChdTC-15, ChdTC-114, pYNH24, and lambda TM-18, a DNA profiling system was developed that verified identities of individual cultured cell lines collected in the Japanese cell banks, JCRB, RCB, and IFO. These highly polymorphic DNA probes include both VNTR (Variable Number of Tandem Repeats) sequences and substantial lengths of unique regions. In the mixed probe system, several distinct bands from four to eight can be used for cell line identification. These bands were widely spread in a range of molecular sizes, and were stable and reproducible under stringent conditions of Southern blot hybridization. Because the DNA profile was specific for each individual human cell line, it is useful not only to authenticate many existing cultured cell lines but also to monitor their identity during propagation in a laboratory, and to confirm newly established lines as unique.

Mapping of the human gene for the human immunodeficiency virus type 1 enhancer binding protein HIV-EP2 to chromosome 6q23-q24

The human gene encoding the human immunodeficiency virus type 1 enhancer binding protein HIV-EP2 has been isolated. Using Southern analysis of human-rodent somatic cell hybrid DNA with a human HIV-EP2-specific cDNA probe, the HIV-EP2 gene was assigned to chromosome 6. The gene was further localized to the region 6q23-24 by fluorescence in situ hybridization.

Identification of eleven single-strand initiation sequences (ssi) for priming of DNA replication in the F, R6K, R100 and ColE2 plasmids

Based on the ability to complement the poor growth of an M13 phage derivative lacking the complementary strand origin, eleven single-strand initiation sequences (ssi) for DNA replication are identified in the F, R6K, R100 and ColE2 plasmids. Six of them were from F, two from near the gamma and alpha origins (ori) of R6K, two from the vicinity of the basic replicon of R100 and one from near the ori of ColE2. They can be classified into two groups based on the morphology of the plaques and the length of nucleotide (nt) sequences required for ssi activity; one group that gives rise to larger and clearer plaques and can be reduced to nearly 100 nt (seven out of eleven), and another that generates smaller and less clear plaques and requires more than 200 nt for full activity (four out of eleven). Sequence homology is detected among some members from both groups. The possible biological roles of the ssi are discussed.

Severe acute graft-versus-host disease by HLA-DPB1 disparity in recombinant family of bone marrow transplantation between serologically HLA-identical siblings: an application of the polymerase chain reaction-restriction fragment length polymorphism method

It has remained to be established that matching of the HLA-DP antigen plays a key role in bone marrow transplantation (BMT), mainly due to the difficulty of the primed lymphocyte test (PLT) method for DP typing. We previously reported an efficient technique for HLA class II genotyping, by digestion of polymerase chain reaction (PCR)-amplified genes with restriction fragment length polymorphisms (RFLP) endonucleases (PCR-RFLP method). DNAs from 46 recipients and corresponding donors in serologically HLA-identical sibling-BMT cases were DP typed by this PCR-RFLP method. Of the 46 cases, five (10.9%) were genetically DP mismatched (recombinant frequency between the DR-DQ and DP subregions was at least 2.7% per meiosis), providing an important opportunity to look at the effect of the disparity only seen in the DP antigen on BMT. Three of the four DP-mismatched BMT cases that could be evaluated developed severe acute graft-versus-host disease, suggesting that DP disparity played an important role in BMT.

Cloning of an activated human ret gene with a novel 5' sequence fused by DNA rearrangement

By transfecting a high-Mr DNA from human stomach cancer into NIH3T3 cells, a transforming sequence that showed homology with the human ret gene was identified. The transforming sequence was found to be generated by a DNA rearrangement in the human ret proto-oncogene. This rearrangement was suggested to have occurred during the transfection procedure. The nucleotide sequences of cDNAs of the rearranged ret gene and deduced amino acid (aa) sequences revealed that the rearrangement had resulted in recombination of the 3' segment of the ret proto-oncogene with a segment of an unknown human sequence, and that the recombination had generated a novel gene encoding a fusion protein of 435 aa. The rearrangement was presumed to be responsible for activation of the ret gene.

The carboxyl terminal amino acid residues of Pseudomonas aeruginosa exotoxin A involved in cell toxicity and pathogenesis, characterized by a neutralizing human monoclonal antibody

Human monoclonal antibody HI-1A4 (IgG3, lambda) neutralized a toxicity caused by pseudomonal exotoxin A (Ex-A) in cell culture and in vivo, and was effective in experimental Pseudomonas aeruginosa infections in mice. HI-1A4 inhibited an Ex-A catalyzed ADP-ribosylation of elongation factor 2 but did not inhibit an incorporation of toxin into a target cell at all. One molecule of HI-1A4 neutralized at least 2 molecules of Ex-A. HI-1A4 retained its binding activity at pH 4.0. The epitope region for HI-1A4 was demonstrated to be a carboxyl terminal end of amino acid residues 591-613 of Ex-A. HI-1A4 might bind to Ex-A carboxyl terminal region outside a target cell, be incorporated into cells as a complex with Ex-A, and inhibit the intracellular function in which the carboxyl terminal part of Ex-A was involved, resulting in the interruption of intoxication of Ex-A.

Modified PCR-RFLP method for HLA-DPB1 and -DQA1 genotyping

We previously developed a new technique for HLA class II genotyping by digestion of polymerase chain reaction-amplified genes with restriction endonucleases (PCR-RFLP method). This PCR-RFLP method is an efficient and convenient typing technique for class II alleles. However, small fragments or bands located close to each other on polyacrylamide gels sometimes prevent precise analysis of the RFLP bands. Furthermore, the restriction enzymes we have reported in the previous papers are not sufficient to identify the genotypes of all heterozygous individuals. Here, we report an improved PCR-RFLP method using some informative restriction enzymes which have either a single cleavage site or, alternatively, no cleavage site in the amplified DNA region, depending on the HLA alleles, making reading of RFLP band patterns much easier. Each second exon of the HLA-DQA1 or -DPB1 gene was selectively amplified from genomic DNAs of 70 HLA-homozygous B-cell lines and 100 healthy Japanese by PCR. Amplified DNAs were digested with restriction endonucleases and then subjected to electrophoresis assaying simply for cutting, or no cutting, of the DNA. ApaLI, HphI, BsaJI, FokI, MboII and Mn1I can discriminate eight alleles of the DQA1 gene. Similarly 19 alleles of the DPB1 gene can be discriminated with Bsp1286I, FokI, DdeI, BsaJI, BssHII, Cfr13I, RsaI, EcoNI, and AvaII enzymes. This modified PCR-RFLP method can be successfully applied to heterozygotes. Thus, the method is technically simpler and more practical for routine HLA typing work than our previous PCR-RFLP method.

HLA-DQB1 genotyping by a modified PCR-RFLP method combined with group-specific primers

We previously reported a simple technique for HLA-DQB genotyping by digestion of polymerase chain reaction-amplified genes with restriction endonucleases (PCR-RFLP method). However, this method has some problems in that some heterozygotes cannot be discriminated from each other. Furthermore, concomitantly amplified product derived from the DQB2 gene by the primers used previously also obstructs precise DQB1 genotyping. To resolve these problems, we have developed two different pairs of specific primers for selective amplification of the DQB1 gene and also used restriction endonucleases which have either a single cleavage site or, alternatively, no cleavage site in the amplified DNA region, depending on the HLA-DQB1 alleles, making reading of RFLP band patterns much easier. The second exon of the DQB1 gene was selectively amplified by DQw1 group-specific primers and/or DQw2,3,4 group-specific primers using genomic DNAs from 70 HLA-homozygous B-cell lines and 50 healthy Japanese. Of the seven DQw1-associated DQB1 alleles, six alleles could be defined by digestion of 6 restriction enzymes, although DQB1*0602 and DQB1*0603 could not be discriminated from each other because of unavailability of suitable enzymes. Similarly, all of the six DQw2,3,4-associated DQB1 alleles could be defined by digestion of 5 restriction enzymes. Using this modified PCR-RFLP method, complete DQB1 genotyping of all heterozygotes is possible except for discrimination between DQB1*0602 and 0603. Thus this method is simpler and more practical for a routine DNA typing than the PCR-SSO method or our previous PCR-RFLP method.

Disposition and metabolism of [14C]sparfloxacin after repeated administration in the rat

Disposition and metabolism of [carbonyl-14C]sparfloxacin (SPFX, 5-amino-1-cyclopropyl-7-(cis-3,5-dimethyl-1-piperazinyl)-6,8-difluoro- 1,4-dihydro-4-oxoquinoline-3-carboxylic acid, AT-4140; CAS 110871-86-8), a novel antimicrobial quinolone, were studied in rats during and after 14 consecutive daily oral administrations at 10 mg/kg. Plasma levels after the 1st and 14th administration were similar in terms of tmax (1 h), Cmax (around 1.35 micrograms eq/ml), T1/2 (3-4 h) and AUC (about 7.3 micrograms eq h/ml). Plasma levels at 0.5 h after each administration were virtually constant in the range of 1.25-2.66 micrograms eq/ml for 14 days, but those at 24 h tended to elevate to about 0.06 micrograms eq/ml, which was an apparent steady state level after the 6th administration. Tissue distribution after the repeated administration was also similar to that after single administration: levels in the kidney, liver, pancreas, submaxillary gland, lung and many others were higher than, or similar to those in plasma, and in brain and some others, lower. Composition of radioactive metabolites in urine was not statistically different from that after single administration. About 20 and 73% of dose were excreted in daily urine and feces, respectively, for 14 days and radioactivity was almost completely excreted within 96 h after the last administration.

[A comparison of the endocrine effects of hypotension induced by nicardipine with those by sodium nitroprusside in dogs]

Plasma catecholamines, plasma renin activity, plasma aldosterone and plasma cortisol during hypotension induced by sodium nitroprusside and nicardipine were studied in 27 mongrel dogs under 0.87% halothane in oxygen. They were randomly divided into three groups: sodium nitroprusside (group S: n = 8), nicardipine (group N: n = 8) and controls (group C: n = 9). Group C received no vasodilator therapy and served as a control. Mean arterial pressure was reduced and maintained at 60 mmHg for 60 minutes in hypotensive groups. No changes were noted in plasma catecholamines and plasma cortisol in group C throughout the experiment, but plasma renin activity and plasma aldosterone decreased progressively. During hypotension induced by sodium nitroprusside and nicardipine, plasma epinephrine was significantly higher than the control value. However, after the hypotensive drugs were discontinued, plasma epinephrine decreased slightly. During and after induced hypotension, plasma renin activity of group N and group S were significantly higher than the control values. The highest levels of plasma renin activity 36.7 ng.ml-1.hr-1 in group N and 23.2 ng.ml-1.hr-1 in group S were observed. Plasma aldosterone concentration was significantly higher than the control value in group N. The maximum increase occurred 30 minutes after discontinuation of the nicardipine and the highest concentration of plasma aldosterone was three times control value. In contrast, in group S, plasma aldosterone was unchanged from the control value. Plasma cortisol concentration of group N was significantly increased than the control value. However, in group S, plasma cortisol concentration showed a slight but not significant increase.(ABSTRACT TRUNCATED AT 250 WORDS)

HTLV-1 Tax induces expression of various immediate early serum responsive genes

Human T-cell leukemia virus type 1 (HTLV-1) is an etiological agent of adult T-cell leukemia (ATL). We showed here by mobility-shift assay that T-cell lines transformed with the virus contained high levels of AP-1 activities. Consistent with this result, these cell lines expressed increased levels of mRNAs encoding the AP-1 proteins, c-Fos, Fra-1, c-Jun, JunB, and JunD. Previously, transcription of the c-fos gene has been reported to be transactivated by the viral transcription factor, Tax1. By using the human T-cell line (JPX-9), in which expression of the Tax1 is inducible, we showed that expression of mRNAs for Fra-1, c-Jun, and JunD was also transactivated by Tax1. Moreover, Tax1 activated expression of two other transcription factors having zinc finger motifs, Egr-1 and Egr-2, in the same cells. The Tax1-inducible transcription factors identified here are encoded by the members of immediate early genes under the control of growth signals. Thus, Tax1 was suggested to replace growth signals, at least in part, by this mechanism.

HIV-EP2, a new member of the gene family encoding the human immunodeficiency virus type 1 enhancer-binding protein. Comparison with HIV-EP1/PRDII-BF1/MBP-1

At least two different types of proteins, NF-kappa B/KBF1 and HIV-EP1/PRDII-BF1/MBP-1, which are members of a family of rel oncoproteins and metal-finger proteins, respectively, bind to the human immunodeficiency virus type (HIV-1) enhancer. As a new member of a HIV-EP1 family that is expressed at a high level in T cells, we have isolated cDNA clones of HIV-EP2 by cross-hybridization with HIV-EP1 cDNA. HIV-EP2 protein consists of 1,833 amino acids and has a molecular weight of 211,000. HIV-EP2 protein is highly homologous with HIV-EP1/PRDII-BF1/MBP-1 in three regions. These three regions contain the potential nuclear localization signal followed by a Ser/Thr-rich region, the DNA-binding domain consisting of a metal-finger structure, and a cluster of acidic amino acids. The DNA-binding property of HIV-EP2 was similar to that of HIV-EP1. Northern blot analysis of HIV-EP2 mRNA indicated relatively high expression in the T cell line Molt-4 and in some tumor cell lines. Furthermore, like HIV-EP1, expression of HIV-EP2 mRNA was greatly induced by mitogen and phorbol ester treatment of Jurkat T cells, suggesting that HIV-EP2 acts in HIV production from latently infected T cells.

Restriction fragment length polymorphisms detected in N-ras-related sequences of rats and their linkage analyses

Novel restriction fragment length polymorphisms (RFLPs) in inbred rats were revealed with the human N-ras gene as probe. Three fragments hybridizing to the probe were detected by Southern blot hybridization under highly stringent conditions, and one of the fragments showed variation in inbred rat strains. Furthermore, on hybridization under low-stringency conditions, an additional fragment hybridizing to the probe was observed, and this fragment also showed interstrain variation. These two variant fragments showed different distributions in 27 inbred rat strains and segregated in backcross progeny as codominant alleles of independent single autosomal loci. Therefore, the loci for these RFLPs were named Nras-1 and Nras-2, respectively. Analyses of linkages between the RFLPs and 11 other loci revealed that the Nras-2 locus was closely linked to the c locus (3.7 +/- 2.6%), which belongs to rat linkage group I.

Deletion of human JK segments by site-specific recombination recognizing the conserved nonamer and heptamer sequences

Mapping and partial sequencing of the productive K chain genomic DNA of FK-001 demonstrated a 1.8-kb deletion including the JK2, JK3, JK4, and JK5 segments. This deletion occurred between the heptamer recombination signal sequence of the JK2 segment and the heptamer-like sequence located 1.8 kb downstream of the JK2 segment. The recombination reaction kept the reciprocally joined signal sequences on the chromosome and deleted the intervening DNA segment. The cloned FK-001 K chain gene was expressed efficiently in mouse myeloma cells, demonstrating that the 1.8-kb deleted region conferred no functions for gene expression.

Roles of phi X174 type primosome- and G4 type primase-dependent primings in initiation of lagging and leading strand syntheses of DNA replication

Eleven single strand initiation sequences (ssi) were isolated from various plasmid genomes using a plaque-morphology assay. Out of seven ssi that require dnaB and dnaC functions for replication in a crude in vitro system, six use a phi X174 type priming mechanism, and a phi X174 type primosome is assembled at these sequences from the purified proteins, n'(priA), n(priB), n"(priC), dnaT, dnaB, dnaC, and primase. The same ssi potentiate dATPase activity of n' protein, and thus represent new n' protein recognition sequences (n'-pas). Based on sequence homology, two structural groups are evident. Two sequences show a strong homology with the phi X174 site, whereas three share extensive homology with the previously characterized n'-pas of ColE1, ssiA(ColE1). All the n'-pas have a potential to form stem and loop structures, although sequence homology between the two classes is absent. In addition to the phi X174 type priming, three ssi do not require either dnaB or dnaC function for replication, and use a G4 type priming, requiring only SSB and primase. The 5' ends of primer RNA synthesized by primase are localized within the vicinity of one of the three blocks of highly conserved nucleotide sequences. Deletions of parts of these conserved sequences result in loss of priming activity, suggesting that they are important for priming on the G4 type ssi, which are termed G site. The general significance of these two types of priming in initiation of lagging or leading strand synthesis as well as various modes of initiation at origins of replication are proposed.

The ABC-primosome. A novel priming system employing dnaA, dnaB, dnaC, and primase on a hairpin containing a dnaA box sequence

A priming mechanism requiring dnaA, dnaB, and dnaC proteins operates on a single-stranded DNA coated with single-stranded DNA-binding protein. This novel priming, referred to as "ABC-priming," requires a specific hairpin structure whose stem carries a dnaA protein recognition sequence (dnaA box). In conjunction with primase and DNA polymerase III holoenzyme, ABC-priming can efficiently convert single-stranded DNA into the duplex replicative form. dnaA protein specifically recognizes and binds the single-stranded hairpin and permits the loading of dnaB protein to form a prepriming protein complex containing dnaA and dnaB proteins which can be physically isolated. ABC-priming can replace phi X174 type priming on the lagging strand template of pBR322 in vitro, suggesting a possible function of ABC-priming for the lagging strand synthesis and duplex unwinding. Similar to the phi X174 type priming, a mobile nature of ABC-priming was indicated by helicase activity in the presence of ATP of a prepriming protein complex formed at the hairpin. The implications of this novel priming in initiation of replication at the chromosomal origin, oriC, and in its contribution to the replication fork are discussed.

DNA binding activity and transcriptional activator function of the human B-myb protein compared with c-MYB

Three members of the myb gene family have been identified in human cDNA libraries c-myb, A-myb, and B-myb. We compared the DNA binding properties of the B-myb and c-myb proteins (B-MYB and c-MYB) using bacterially synthesized B-MYB and c-MYB in DNase I footprinting. B-MYB bound to most of the c-MYB binding sites examined, including the c-MYB binding site, MBS-I, in the simian virus (SV) 40 enhancer, in which the most frequent sequence was CCTAACTG. The MBS-I site was an enhancer element dependent on B-MYB and c-MYB in a co-transfection assay that used the B-myb or c-myb expression plasmid. Some sites in the SV40 genome, including the MBS-BI site, had high affinity with B-MYB but little or no affinity with c-MYB, in which the most frequent sequence was AGAAANPyrG. The MBS-BI site was an enhancer element dependent on B-MYB and a very weakly dependent on c-MYB. Our results showed that B-MYB is a transcriptional activator, like c-MYB, and that although B-MYB and c-MYB have similar sequence specificity for DNA binding some sequences were recognized by B-MYB preferentially.

Polymorphisms detected in actin-related sequences of rats (Rattus norvegicus)

Southern blot hybridization of EcoRI digests of DNAs from 13 rat strains using human cardiac actin gene as a probe revealed polymorphisms in actin-related sequences of rats. EcoRI fragments of 11 kb, 7 kb, 6 kb, 5 kb, 4.5 kb and 4 kb detected in several strains were absent in the remaining strains. The presence of these fragments was suggested to be due to presence of extra sequences homologous to the actin genes, such as processed pseudogenes, in the particular strains. The 13 strains were assigned to each of 7 specific patterns of the polymorphic EcoRI fragments. It was concluded that the polymorphisms of actin-related sequences should be useful for genetic monitoring of laboratory rats.

Transcriptional regulation of early growth response genes in FOS-expressing PC-12 cells

Deregulated c-fos expression in the rat pheochromocytoma cell line, PC-12, causes pronounced downregulation of nerve growth factor (NGF)-induced c-fos and c-jun activation, accompanied by a block in NGF-induced differentiation of PC-12 cells. The FOS-expressing PC-12 cells were exposed to diverse agents such as NGF, epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6), dibutyryl cyclic adenosine 3',5' monophosphate (db cAMP), and Ca-ionophore; and the expression of egr-1, c-fos, c-jun, jun-B, and jun-D was analyzed. Pronounced downregulation of c-fos, c-jun, and--to a lesser extent--jun-B was observed on treatment with NGF, bFGF, db cAMP, and Ca-ionophore, whereas EGF-induced activation of these early response genes was not inhibited in FOS-expressing PC-12 cells. Ca-ionophore- and db cAMP-induced egr-1 activation in PC-12 fos cells was completely inhibited. Both parent and PC-12 fos cells expressed similar high basal levels of jun-D, whose expression was the least regulatable by all of these agents. Transfection of fos promoter-chloramphenicol acetyltransferase (promoter-CAT) plasmid into these stable FOS-expressing PC-12 cells revealed that these effects are exerted at the fos promoter level.

Isolation of human fos-related genes and their expression during monocyte-macrophage differentiation

cDNA clones of human fos-related genes fra-1 and fra-2 were isolated by screening human c-DNA libraries with human fos DNA as a probe. We obtained human fra-1 cDNA clones that can code for a protein of 271 amino acid residues with a calculated molecular weight of 29,413 and showed 90% similarity with rat fra-1 protein. A new fos-related gene, fra-2, has one long open reading frame of 326 amino acids, and can code for a protein with a calculated molecular weight of 35,193. Two regions, a leucine zipper domain and C-terminal region, are conserved in the fos gene family. The fra-2 gene also harbors these two regions. Transcription of the fos, fra-1 and fra-2 genes was induced by phorbol ester (TPA) stimulation of U937 human monocytic cells. On TPA stimulation, the transcriptions of fos, fra-1 and fra-2 were detectable after 30, 60 and 120 min and maximum after 60, 90 and 240 min, respectively. These findings suggest that expression of the fos gene family is regulated by an orderly mechanism.

Requirement of protein co-factor for the DNA-binding function of the human ski proto-oncogene product

We identified the human c-ski gene product (c-Ski) as a protein with the apparent molecular weight of 100,000, p100c-ski, by using a c-Ski-specific polyclonal antibody. p100c-ski was a nuclear protein and p100c-ski in nuclear extracts of Molt4 cells bound to calf thymus DNA cellulose, but the bacterially synthesized c-Ski did not, suggesting that Ski was associated with another protein(s) and that the Ski complex had DNA-binding activity. This hypothesis was supported by the finding that the bacterially synthesized Ski bounds to DNA cellulose after being mixed with a nuclear extract of Molt4 cells. By use of a series of deletion mutants of Ski synthesized in an in vitro translation system, two portions in Ski were found to be necessary for the DNA binding of the Ski complex: the N-proximal portion containing a cystein/histidine-rich domain and the C-terminal portion including a region rich in basic amino acids.

Dependence of cellular energy metabolism on the intracellular pH of isolated rabbit parietal cells

The cellular energy metabolism under various extracellular pH (pHe) was investigated in parietal cells isolated from rabbit gastric mucosae. Activity of parietal cells was checked by measuring effects of histamine and db-cAMP on the accumulation of aminopyrine in the intracellular canaliculi. The relationship between the intracellular pH (pHi) and pHe was determined by using a fluorescence probe 2',7'-bis(carboxyethyl)-5(6)-carboxyfluorescein (BCECF) in suspensions of isolated parietal cell. The pHi was a linear function of pHe and it changed by 0.63 pH unit per 1.0 unit change in pHe. The internal [H+] was equal to the external [H+] at approximately pH 7.0. The respiratory rate of the cell depended on pHi. Values of [ATP] + [ADP] and intracellular inorganic phosphoric acid [Pi] were almost independent of pHi, whereas the [ATP]/[ADP] ratio decreased with increase in pHi. In addition, the standard free energy of ATP(delta Go'ATP) decreases as pHi increases. The calculated available free energy of ATP, which is the sum of delta Go'ATP and -RTlog[ATP]/([ADP] [Pi]), was independent of pHi in the range from pHi 6.2 to 7.6 and its value was about -11.7 kcal/mol. Furthermore, [ATP], [ADP], and [Pi] in the intracellular space were not affected by the presence of histamine or dibutyryl cAMP in media. It was indicated that the available free energy of ATP did not change in the transformation from resting to acid-secreting states, and the phosphorylation potential might have an important role in control of homeostasis in energy metabolism.

Functional analysis of mononuclear cells infiltrating into tumors: establishment of a new system to obtain functionally active tumor-infiltrating cells

We have demonstrated that tumor-infiltrating T cells play a crucial role in tumor growth. In order to investigate the precise function of tumor-infiltrating cells, we avoided the use of any enzyme for separation of tumor-infiltrating cells from the solid tumor mass and established a new system in which we could easily obtain functionally active tumor-infiltrating cells in large amounts from the peritoneal cavity of T-9 gliosarcoma-sensitized rats. In this system, viable T-9 cells were intraperitoneally administered and peritoneal exudate cells were recovered. Importantly, cells obtained from the intraperitoneal cavity are phenotypically and functionally indistinguishable from those obtained from subcutaneous tumor masses. Furthermore, injection of purified lymphocyte migration factor-b resulted in the accumulation of CD8 (+) cytotoxic T cells in the peritoneal cavity. Therefore, this system also provides a means by which the in vivo function of chemotactic factor can be tested.

[Specific cytoplasmic crystalline inclusions in multiple myeloma with amyloidosis]

It is widely known that multiple myeloma is sometimes followed by amyloidosis. It is also not particularly rare that inclusions exist in myeloma cells. However, there has been no previous report of a case of myeloma with both inclusions and amyloidosis. A 60-year-old female initially complained of a tendency to bleed, which was caused by fibrinolysis. Amyloid deposition in bone marrow stroma and the gastric submucosa was recognized, in addition to crystalline inclusion in the cytoplasm of myeloma cells. An immunoelectron microscopic study demonstrated the amyloid fibrils and the crystals to react positively to anti-lambda serum. No crystals were found in macrophages, and no relationship was recognized between lysosomes and crystalline inclusions in the cytoplasm of myeloma cells. This case had disturbed transportation or secretion of the lambda type L chain and it was considered that crystals derived from the lambda type L chain were formed in the cytoplasm of myeloma cells.

Novel restriction fragment length polymorphism of the growth hormone gene in inbred rats

A novel restriction fragment length polymorphism in inbred rats was detected by Southern blot analysis with rat growth hormone cDNA as a probe. Four alleles, characterized by PstI fragments of 1.2, 1.1, 0.9, and 0.7 kb, respectively, were detected in 27 strains examined. The same distribution of polymorphisms was observed on digestion of DNAs of these strains with three other enzymes, PvuII, HindIII, and BamHI. Moreover, the same differences in length of allelic restriction fragments were obtained with these restriction enzymes as with PstI. These findings suggested that the polymorphism was caused by insertion or deletion of variable DNA segments in the second intron of the growth hormone gene. Linkage analyses using backcross progeny provided no evidence for close linkage between the restriction fragment length polymorphism locus and 10 other loci examined.

Restriction fragment length polymorphism of cardiac myosin heavy chain gene in rats and its strain distribution

The distribution of an RFLP in EcoRI fragments of the cardiac myosin heavy chain gene among 29 strains of laboratory rats was examined. Southern blot hybridization of rat genomic DNAs with rat cardiac myosin heavy chain cDNA as a probe demonstrated an interstrain variation in one of eight EcoRI fragments. Of the 28 inbred strains examined, 10 had a fragment of 10 kbp, whereas 18 had a fragment of 7.5 kbp. The 15 samples of the remaining strain (Iar: WI outbred stock) had fragments of either 7.5 kbp or 10 and 7.5 kbp, indicating that this strain has maintained heterogeneity of these fragments.

[Effects of propiverine hydrochloride (P-4) and its metabolites on urinary bladder function in anesthetized rats]

The effects of P-4 and its active metabolites, 1-methyl-4-piperidyl diphenylpropoxyacetate N-oxide[P-4(N----O)], 1-methyl-4-piperidyl benzilate N-oxide [DPr-P-4 (N----O)] and 1-methyl-4-piperidyl benzilate hydrochloride (DPr-P-4), on urinary bladder function were investigated in urethane anesthetized rats. By cystometrography, P-4 (2, 4 mg/kg, i.v.) and P-4 (N----O) (4 mg/kg, i.v.), which have direct action on smooth muscles, significantly increased the maximum vesical volume. As for rhythmic bladder contractions, P-4 (1,2,4 mg/kg, i.v.) and P-4 (N----O) (2, 4 mg/kg, i.v.) significantly decreased the frequency with a slight decrease in the amplitude. On the other hand, DPr-P-4 (N----O) (0.1, 0.5 mg/kg, i.v.) and DPr-P-4 (0.01, 0.05 mg/kg, i.v.), which have anticholinergic effects, significantly inhibited the maximum vesical pressure on the cystometrograms, and DPr-P-4 (N----O) (0.1, 0.5 mg/kg, i.v.) and DPr-P-4 (0.005, 0.05 mg/kg, i.v.) significantly inhibited the amplitude of the rhythmic bladder contractions. The effects of flavoxate and papaverine were similar to those of P-4 and P-4 (N----O), but the effects of propantheline and atropine were similar to those of DPr-P-4 (N----O) and DPr-P-4 in these two experimental methods. These results suggest that the clinical effects of P-4 are based not only on the actions of P-4 itself but also on those of its active metabolites.

Isolation of human cDNA clones of ski and the ski-related gene, sno

cDNA clones of ski and the ski-related gene, sno, were obtained by screening human cDNA libraries. The predicted open reading frame of h-ski could encode a protein of 728 amino acid residues. The h-ski protein is highly homologous with the v-ski protein. The overall homology between h-ski and v-ski is 91% at the amino acid level. DNA sequencing analysis revealed two types of cDNA clones from the sno (ski-related novel gene) gene, possibly due to alternative splicing. The first type, named snoN (non Alu-containing), encoded a protein of 684 amino acid residues. The second type, named snoA (Alu-containing), encoded a protein of 415 amino acid residues. The first 366 amino acid residues of snoN and snoA are the same, but subsequent amino acids show divergence. Several transcripts of h-ski (6.0, 4.7, 3.8, 3.0, 2.1 and 1.8 kb) were detected. The mRNAs of h-sno were 6.2, 4.4 and 3.2kb.

[Randomized-controlled study of treatment with UFT-MMC or UFT-ACR in advanced gastric cancer. Tohoku Study Group of Cancer Treatment for the Digestive Organs]

The effect of UFT-MMC- or UFT-ACR-therapy on the unresectable or recurrent gastric cancer was studied by a multicenter, randomized-controlled trial. All the patients who were randomly divided into the two groups were administered orally with 400 or 600 mg/day of UFT everyday. In addition, the UFT-MMC group was intravenously injected weekly for three weeks and then triweekly after six weeks with 6 or 8 mg/body of MMC, while the UFT-ACR group was intravenously injected with 20 mg/body of ACR for 5 serial-days every three weeks. Out of 88 cases registered, 75 (85.2%) were evaluable, consisting of 40 (31 complete cases) in UFT-MMC and 35 (27 complete cases) in UFT-ACR. There was no difference in various background factors between the two groups. PR, NC and PD was 10/31, 15/31 and 6/31 in the UFT-MMC group, whereas 0/27, 22/27 and 5/27 in the UFT-ACR group, respectively. The efficacy in the former group was higher, though not significant (U-test, p = 0.052), than that in the latter group. However, there was no difference in the 50% survival time (4.9 months in UFT-MMC vs. 5.4 months in UFT-ACR) of the either group.

Cloning of ara, a putative Arabidopsis thaliana gene homologous to the ras-related gene family

A putative Arabidopsis thaliana gene, ara, homologous to the ras-related gene family was isolated from a genomic library by low-stringency hybridization with a v-Ha-ras probe. The putative gene has a coding frame for a 218-residue protein (Mr 24,210), which is interrupted by one intron. The amino acid residues conserved in proteins of the ras gene family, which are important for GTP binding, GTP hydrolysis and membrane attachment, are also present in the ara protein. An unusually long homopyrimidine-homopurine tract was found about 100 bp upstream from the methionine start codon. A unique sequence, 5'-AACAAAACCAAAGTGATATGC-3', was found three times in the 5'-noncoding region and once in the intron.

Isolation of human cDNA clones of myb-related genes, A-myb and B-myb

cDNA clones of the myb-related genes A-myb and B-myb were obtained by screening human cDNA libraries. The predicted open reading frame of B-myb could encode a protein of 700 amino acid residues. Although the C-terminal end has not been cloned yet, an almost entire coding region of A-myb, which is 745 amino acid long, was determined. The A-myb and B-myb proteins are highly homologous with the myb protein in three regions. Domain I, which is 161 amino acid long, is well conserved in the myb gene family. The homology between human-myb and A-myb in domain I is 90% at the amino acid level. Domain II, which is about 85 amino acid long, is less well conserved. Although it is a short stretch, domain III is found in the C-terminal region. The mRNAs of A-myb and B-myb were 5.0 and 2.6 kb, respectively. The mRNA expression pattern of the myb gene family in various tumors is presented.

Endobronchial changes in chronic pulmonary venous hypertension

The bronchial venous system closely communicates with the pulmonary circulation. To assess the changes in the bronchial circulation in chronic pulmonary venous hypertension, fiberoptic bronchoscopy and right heart catheterization were performed in 31 patients with mitral stenosis. Nonpulsatile submucosal vessel dilatation, consistently seen in all patients and called the vessel dilatation score, was assessed visually by three independent bronchoscopists. The vessel dilatation score was correlated more closely with pulmonary artery wedge pressure (r = 0.687) (p less than 0.001) than to mean pulmonary artery pressure (r = 0.531) (p less than 0.01) and right atrial pressure (r = 0.178) (NS). The vessel dilatation score decreased after reduction of the left atrial load by surgery. These results suggest that the dilated vessels observed in patients with mitral stenosis are bronchial veins that are engorged secondary to increased blood flow via bronchopulmonary anastomoses.

Giant pigmented tumour of the scalp--a diffuse neurofibroma or a congenital naevus showing neurofibromatous changes? Immunohistochemical and electron microscopic studies

A case of giant pigmented tumour of the scalp which developed in a 47-year-old woman is reported. Macroscopically, the tumour showed a peculiar two-layered structure, consisting of an upper non-pigmented and a lower pigmented portion. Histologically, it was composed of elongated neurofibromatous tumour cells with abundant collagen fibres in the non-pigmented portion and round naevus-like cells with abundant melanin pigment in the pigmented portion. S-100 protein and neurone-specific enolase were demonstrated in most of the tumour cells, but neurofilament and myelin basic protein were not detected. Electron microscopy revealed melanosomes in the tumour cells of the pigmented portion. These findings might support a melanocytic origin for the tumour, but the lack of superficial pigmentation and the associated hair loss were against this. The tumour may represent an example of duality of neural crest differentiation.

Genetic alterations of the c-erbB-2 oncogene occur frequently in tubular adenocarcinoma of the stomach and are often accompanied by amplification of the v-erbA homologue

We analyzed for alterations of the c-erbB-2 oncogene in 35 human stomach cancers and 8 cell lines derived from human stomach cancer. Amplification of c-erbB-2 was found in approximately 40% (5/13) of the tubular adenocarcinomas of the stomach examined, including 4 of 10 fresh tumors and one of 3 cell lines, but not in other histological types of stomach cancer examined (0/30), including 25 fresh tumors and 5 cell lines. This result strongly suggests that amplification of c-erbB-2 occurs frequently in tubular carcinomas in stomach cancer. Rearrangement of c-erbB-2 was also detected in one tubular adenocarcinoma. The rearranged fragment carried the 3' half, but not the 5' sequence, of the c-erbB-2 gene. Furthermore, one of the cellular homologues of v-erbA was amplified in 3 of 4 fresh tumors carrying the amplified c-erbB-2 gene. Both c-erbB-2 and the v-erbA homologue were expressed in all the stomach cancer cell lines tested.