251
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Cheng Q, Saul A. Sequence analysis of the apical membrane antigen I (AMA-1) of Plasmodium vivax. Mol Biochem Parasitol 1994; 65:183-7. [PMID: 7935625 DOI: 10.1016/0166-6851(94)90127-9] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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252
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Cheng Q, Cant C, Moll T, Hofer-Warbinek R, Wagner E, Birnstiel M, Bach F, de Martin R. NK-kappa B subunit-specific regulation of the I kappa B alpha promoter. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)36866-7] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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253
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Prescott N, Stowers AW, Cheng Q, Bobogare A, Rzepczyk CM, Saul A. Plasmodium falciparum genetic diversity can be characterised using the polymorphic merozoite surface antigen 2 (MSA-2) gene as a single locus marker. Mol Biochem Parasitol 1994; 63:203-12. [PMID: 8008018 DOI: 10.1016/0166-6851(94)90056-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The genetic diversity of Solomon Island Plasmodium falciparum isolates was examined using MSA-2 as a single locus marker. Amplification of MSA-2 gene fragments showed size polymorphism and the presence of mixed infections. Sequence analysis indicated a global representation of MSA-2 alleles with representatives of 3D7/CAMP allelic subfamilies and the FCQ-27 allelic family being identified. A simplified method of characterisation, utilising PCR-RFLPs of MSA-2 gene fragments, was developed. The RFLPs allowed identification of allelic families and further distinction within the 3D7/CAMP family. The amplification of MSA-2 gene fragments from culture derived lines revealed a loss of diversity for a number of Solomon Island isolates. Genomic diversity was confirmed for Solomon Island lines, along with Papua New Guinean and Thai lines, by the generation of 7H8/6 fingerprints. All lines were distinct and band sharing frequencies and Wagner tree construction failed to identify any geographic clustering.
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254
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Cheng Q, Liu EX, Saul A. Peptides for inducing cross-reactive anti-malarial antibodies. PEPTIDE RESEARCH 1994; 7:13-9. [PMID: 7517231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Immunological cross-reactions between malarial proteins are frequently observed. This paper describes an approach to generate such antibody responses that target many parasite proteins using a limited number of peptides as immunogens. Peptides used contained a known epitope, NKND, that is common to many malarial proteins or combinations of tri-peptides which are commonly present in parasite proteins. One of the two NKND-containing peptides elicited antibodies reacting to six parasite proteins and fusion proteins containing NKND. The antibody specificity was directed to NKND. Two of the four combination peptides were recognized by hyperimmune human sera and mouse immune serum in vitro, and one elicited antibodies recognizing parasites on immunofluorescence assay.
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255
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Sarraf D, Eezzuduemhoi RD, Cheng Q, Wilson MR, Lee DA. Aqueous and vitreous concentration of mitomycin C by topical administration after glaucoma filtration surgery in rabbits. Ophthalmology 1993; 100:1574-9. [PMID: 8414418 DOI: 10.1016/s0161-6420(93)31442-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
PURPOSE The authors investigated the aqueous and vitreous pharmacokinetics of mitomycin after postoperative topical administration in rabbits. METHODS Filtration surgery was performed in one eye of each rabbit. On the first postoperative day, mitomycin solution (0.4 mg/ml) was administered by either topical drop or cellulose sponge in both eyes of each rabbit. Aqueous and vitreous paracenteses were performed at 0.25, 0.5, 1, 2, 3, and 4 hours thereafter. Three rabbits were tested at each time interval for each type of administration. RESULTS After topical drop administration, the peak aqueous concentration was 0.03 +/- 0.02 microgram/ml (mean +/- standard error) in surgical eyes and 0.06 +/- 0.03 microgram/ml in control eyes. After sponge administration, the peak aqueous concentration was 0.10 +/- 0.03 microgram/ml in surgical eyes and 0.08 +/- 0.04 microgram/ml in control eyes. Peak aqueous concentrations from drop and sponge applications were achieved at 1 to 2 hours after administration. Vitreous levels were well below the concentration known to cause retinal toxicity at all time intervals tested. CONCLUSION Postoperative topical administration of mitomycin was successful in delivering mitomycin into the aqueous humor of rabbit eyes. Alternative methods of mitomycin application from the currently popular intraoperative administration may be beneficial in situations in which mitomycin delivery across intact conjunctiva may be desirable.
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de Martin R, Vanhove B, Cheng Q, Hofer E, Csizmadia V, Winkler H, Bach FH. Cytokine-inducible expression in endothelial cells of an I kappa B alpha-like gene is regulated by NF kappa B. EMBO J 1993; 12:2773-9. [PMID: 8334993 PMCID: PMC413527 DOI: 10.1002/j.1460-2075.1993.tb05938.x] [Citation(s) in RCA: 250] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The transient expression of many different genes is mediated by the inducible transcription factor p50-p65 NF kappa B, which in turn is regulated by complex formation with its inhibitor I kappa B alpha. We describe here that in porcine aortic endothelial cells, either IL-1 alpha, TNF alpha or LPS upregulates an inhibitor of NF kappa B which we refer to as ECI-6. ECI-6 is by structural and functional criteria an I kappa B alpha protein, the porcine homologue of MAD-3, pp40 and RL/IF-1. We have studied the promoter of the ECI-6/I kappa B alpha gene and provide three lines of evidence that its expression is directly regulated by NF kappa B. First, the 5' regulatory region of ECI-6/I kappa B alpha contains two sites that bind NF kappa B in electrophoretic mobility shift assays. Second, expression following transfection of an ECI-6/I kappa B alpha promoter-luciferase reporter construct is dependent on a co-transfected NF kappa B-p65 subunit. Third, pretreatment of endothelial cells with antioxidants, agents that inhibit activation of NF kappa B, inhibit the expression of ECI-6/I kappa B alpha. We conclude that the regulated expression of ECI-6/I kappa B alpha could represent a novel feedback mechanism by which NF kappa B downregulates its own activity after transient activation of target genes has been achieved.
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257
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Cheng Q, Stowers A, Huang TY, Bustos D, Huang YM, Rzepczyk C, Saul A. Polymorphism in Plasmodium vivax MSA1 gene--the result of intragenic recombinations? Parasitology 1993; 106 ( Pt 4):335-45. [PMID: 8100358 DOI: 10.1017/s003118200006707x] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The diversity in a 925 bp portion of the Plasmodium vivax MSA1 gene in isolates from the Philippines, China, the Solomon Islands and Papua New Guinea was investigated. A total of 74 base pair changes was found in the amplified fragment from 18 isolates. Most of these changes were single or double base pair substitutions. In several regions, these point changes were tightly linked with one set always present or always absent in the different isolates. Seven such blocks were identified. These blocks were present in different combinations in the different isolates indicating that extensive intragenic recombination has occurred.
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258
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Cheng Q, Hwa V, Salyers AA. A locus that contributes to colonization of the intestinal tract by Bacteroides thetaiotaomicron contains a single regulatory gene (chuR) that links two polysaccharide utilization pathways. J Bacteriol 1992; 174:7185-93. [PMID: 1429442 PMCID: PMC207410 DOI: 10.1128/jb.174.22.7185-7193.1992] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Previously, we isolated two Tn4351-generated mutants of Bacteroides thetaiotaomicron (46-1 and CS3) that were unable to grow either on heparin or on chondroitin sulfate. This phenotype was unexpected, since the heparin and chondroitin sulfate utilization pathways had appeared from earlier studies to be independent of each other. Mutants 46-1 and CS3 were also of interest because both were unable to compete successfully with wild-type B. thetaiotaomicron in the intestinal tracts of germfree mice. Thus, both appeared to have a colonization defect. We have now cloned the chromosomal locus in which the transposon insertions in 46-1 and CS3 occurred. Southern blot analysis showed that the Tn4351 insertions in 46-1 and CS3 were about 100 bp apart. Using complementation and insertional mutagenesis, we localized the region affected by the 46-1 and CS3 insertions to within 2.5 kbp. This DNA segment was sequenced and found to contain a 401-codon open reading frame (ORF1) and the N-terminal segment of a second open reading frame (ORF2), which was downstream of ORF1 and transcribed in the same direction. The deduced amino acid sequence of ORF1 showed significant homology to that of a putative positive regulator of an arylsulfatase gene in Klebsiella aerogenes. ORF2 was at least 381 amino acids long and did not exhibit homology to any proteins in the data bases searched. Transposon insertions in both mutants 46-1 and CS3 disrupted ORF1. The results of insertional mutagenesis and complementation experiments indicated that ORF2 was not essential for growth on chondroitin sulfate or heparin. Thus, the chondroitin sulfate-negative and heparin-negative phenotypes of 46-1 and CS3 appear to be due to the interruption of a regulatory gene encoded by ORF1 and not to a polar effect of the insertions on a downstream gene(s). The gene encoding ORF1 has been designated chuR, for regulation of chondroitin sulfate and heparin utilization. Transcriptional fusion studies showed that the expression of chuR occurred at the same level under inducing and noninducing conditions, in contrast to the regulated expression of structural genes of the chondroitin sulfate utilization system. chuR was not autoregulated, nor was its expression affected by a mutation (46-4) that eliminated the expression of all chondroitin sulfate utilization genes but did not affect the utilization of heparin.
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259
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Cheng Q. [Effect of cordyceps sinensis on cellular immunity in rats with chronic renal insufficiency]. ZHONGHUA YI XUE ZA ZHI 1992; 72:27-9, 63. [PMID: 1315612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Animal model of chronic renal failure (CRF) was induced in wistar rats by 5/6 nephrectomy. Half of the rats were treated with Cordyceps sinensis (CS) in form of decoction. It was found that CS has mitogenic effect on spleen lymphocytes, and is capable of increasing the production of IL-2 from splenocytes of the CRF rats. IL-2 absorbency of the splenocytes was promoted by CS. CS also exhibited such therapeutic effects on CRF animal as to decrease the level of BUN and serum creatinine and to increase the level of hemoglobin. These results indicate that CS has a regulative effect on cellular immunity in CRF rats.
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260
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Saul A, Cooper J, Hauquitz D, Irving D, Cheng Q, Stowers A, Limpaiboon T. The 42-kilodalton rhoptry-associated protein of Plasmodium falciparum. Mol Biochem Parasitol 1992; 50:139-49. [PMID: 1542308 DOI: 10.1016/0166-6851(92)90251-e] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The gene coding for a 42-kDa rhoptry protein of Plasmodium falciparum has been cloned. On the basis of prior monkey vaccination studies, this protein is regarded as an important vaccine candidate, but its identity has been the subject of considerable uncertainty. Analysis of the cloned sequence shows that it is a basic, hydrophobic protein, without repetitive elements, unrelated to any of the previously postulated gene products and shows minimal sequence diversity. The availability of the corresponding recombinant protein will enable studies of its efficacy in human vaccine trials to be undertaken.
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261
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Cheng Q, Jones G, Liu EX, Kidson C, Saul A. Identification of a common Plasmodium epitope (CPE) recognised by a pan-specific inhibitory monoclonal antibody. Mol Biochem Parasitol 1991; 49:73-82. [PMID: 1723149 DOI: 10.1016/0166-6851(91)90131-o] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
A Plasmodium falciparum genomic expression library was screened with a monoclonal antibody produced from mice infected with Plasmodium yoelii. Eleven unique clones were isolated all of which contained the sequence NKND, IKND or KKND. This sequence was confirmed as the epitope of M26-32 by testing a series of overlapping peptides and the allowable substitutions determined by testing the binding of M26-32 to peptides containing all possible single amino acid replacements of NKND. Potential epitopes of M26-32 occur in many plasmodial proteins and this is consistent with the large number of proteins recognised in these parasites by Western blotting. Since this monoclonal antibody shows marked in vitro inhibition of P. falciparum growth, these data suggest that an anti-malarial vaccine may be produced by targeting such common plasmodial epitopes without necessarily identifying the corresponding antigens.
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262
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Feldhaus MJ, Hwa V, Cheng Q, Salyers AA. Use of an Escherichia coli beta-glucuronidase gene as a reporter gene for investigation of Bacteroides promoters. J Bacteriol 1991; 173:4540-3. [PMID: 2066346 PMCID: PMC208121 DOI: 10.1128/jb.173.14.4540-4543.1991] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
We have constructed transcriptional fusion vectors for use in Bacteroides spp., a genus of gram-negative obligate anaerobes found in high numbers in the human colon. The reporter group in these vectors is a promoterless beta-glucuronidase gene from Escherichia coli (uidA). Two of the vectors (pMJF-2 and pMJF-3) replicate in Bacteroides spp. The third, pCQW-1, does not replicate in Bacteroides spp. and can be used to introduce E. coli beta-glucuroindase fusions into the Bacteroides chromosome.
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263
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Cheng Q, Blackett PR, Wang CS, Fesmire JD, Corder CN. Use of plasma lipoprotein lipase activity without heparin injection for detection of homozygous and heterozygous lipoprotein lipase deficiency. Ann N Y Acad Sci 1991; 623:410-2. [PMID: 2042850 DOI: 10.1111/j.1749-6632.1991.tb43751.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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264
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Ontko JA, Cheng Q, Yamamoto M. Metabolic factors underlying high serum triglycerides in the normal hamster. J Lipid Res 1990; 31:1983-92. [PMID: 2086697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Comparative lipid metabolism of rats and hamsters was investigated to determine the metabolic basis for the relatively high concentrations of serum triglycerides in the hamster. It was found that serum free fatty acids (FFA) in the hamster are higher than in the rat in the fed condition. In addition, a higher percentage of the fatty acids esterified in the liver of the hamster is utilized for triglyceride synthesis. These factors combine to elevate hepatic triglyceride synthesis in the hamster. However, triglyceride does not accumulate in the liver in these animals in the fed state. In fact, liver triglycerides are lower in the fed hamster than in the fed rat, and the hamster stores much less triglyceride in liver lipid droplets than does the rat in this nutritional state. Most of the liver triglyceride in fed hamsters is present in dense particles corresponding to vesicular lipoprotein triglyceride in the secretory pool. In isolated organ perfusion experiments hamsters livers exhibited greater net triglyceride secretion than did rat livers. Serum triglycerides in the hamster remain elevated in the fasting state. In this condition the high proportion of free fatty acids utilized for liver triglyceride synthesis, relative to that incorporated into hepatic phospholipids, persists in the hamster and marked liver triglyceride accumulation occurs. Lipid droplets are extremely abundant in these livers. The present study implicates increased conversion of free fatty acids to triglyceride in the liver and increased hepatic production of very low density lipoproteins (VLDL) in the hamster in the genesis of the hyperglyceridemia characteristic of this species.
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265
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Ontko JA, Cheng Q, Yamamoto M. Metabolic factors underlying high serum triglycerides in the normal hamster. J Lipid Res 1990. [DOI: 10.1016/s0022-2275(20)42262-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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266
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Cheng Q, Blackett P, Jackson KW, McConathy WJ, Wang CS. C-terminal domain of apolipoprotein CII as both activator and competitive inhibitor of lipoprotein lipase. Biochem J 1990; 269:403-7. [PMID: 2386483 PMCID: PMC1131591 DOI: 10.1042/bj2690403] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
In this study we have prepared peptides of the C-terminal domain of apolipoprotein CII (ApoCII) by a solid-peptide-synthesis technique and demonstrated that the C-terminal tetrapeptide, Lys-Gly-Glu-Glu, represents an inhibitor of lipoprotein lipase. The tetrapeptide not only inhibits the basal activity of lipoprotein lipase, but also blocks the activation effect of native ApoCII. The lengthening of this tetrapeptide resulted in a corresponding increase in affinity for lipoprotein lipase. This suggested that amino acids other than those of the C-terminal tetrapeptide also contribute to the binding affinity of ApoCII for lipoprotein lipase. On the basis of an essential requirement of the ApoCII terminal domain for binding to lipoprotein lipase, we suggest that the initial interaction of ApoCII, mediated via the C-terminal tetrapeptide, promotes the proper alignment of ApoCII with lipoprotein lipase, followed by the weak interaction of the ApoCII activator domain with the lipoprotein lipase activator site, enhancing the lipolysis process.
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267
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Gimble JM, Dorheim MA, Cheng Q, Medina K, Wang CS, Jones R, Koren E, Pietrangeli C, Kincade PW. Adipogenesis in a murine bone marrow stromal cell line capable of supporting B lineage lymphocyte growth and proliferation: biochemical and molecular characterization. Eur J Immunol 1990; 20:379-87. [PMID: 2178944 DOI: 10.1002/eji.1830200222] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Recent advances in long-term bone marrow (BM) culture techniques have allowed investigators to dissect cellular components responsible for lympho hematopoiesis. Consequently, a number of "stromal" cell clones have been developed which are capable of supporting B lineage lymphocyte growth and proliferation in vitro by direct cell-cell interactions and the release of cytokines. While much work has focused on the support function of these cells, questions remain regarding their own differentiation potential. We have examined adipogenesis in the cloned BM stromal cell, BMS2. The presence of hydrocortisone, methylisobutylxanthine, or 30% fetal calf serum each accelerated adipocyte differentiation. This process was accompanied by the accumulation of triglycerides and cholesterol esters along with the induction of adipocyte-specific enzymes. Likewise, the steady-state level of mRNA transcripts increased for genes related to lipid metabolism. However, the pattern of mRNA expression in BMS2 adipocytes differed from that of a well-established, pre-adipocyte cell line, 3T3-L1, with respect to the following genes: glycerol phosphate dehydrogenase, CAAT/enhancer binding protein and angiotensinogen. Adipocyte BMS2 cells retailed the ability to support stromal cell-dependent B lineage lymphocytes in methylcellulose assays. The adipocytes continued to express macrophage-colony-stimulating factor mRNA constitutively and interleukin 6 mRNA in an inducible manner, similar to the BMS2 pre-adipocytes. Together, these data document a close developmental relationship between a specialized fibroblasts and adipocytes in the BM and suggest that adipocyte stromal cells may play an active role in lympho-hematopoiesis.
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268
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Cheng Q, Michels CA. The maltose permease encoded by the MAL61 gene of Saccharomyces cerevisiae exhibits both sequence and structural homology to other sugar transporters. Genetics 1989; 123:477-84. [PMID: 2689282 PMCID: PMC1203819 DOI: 10.1093/genetics/123.3.477] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The MAL61 gene of Saccharomyces cerevisiae encodes maltose permease, a protein required for the transport of maltose across the plasma membrane. Here we report the nucleotide sequence of the cloned MAL61 gene. A single 1842 bp open reading frame is present within this region encoding the 614 residue putative MAL61 protein. Hydropathy analysis suggests that the secondary structure consists of two blocks of six transmembrane domains separated by an approximately 71 residue intracellular region. The N-terminal and C-terminal domains of 100 and 67 residues in length, respectively, also appear to be intracellular. Significant sequence and structural homology is seen between the MAL61 protein and the Saccharomyces high-affinity glucose transporter encoded by the SNF3 gene, the Kluyveromyces lactis lactose permease encoded by the LAC12 gene, the human HepG2 glucose transporter and the Escherichia coli xylose and arabinose transporters encoded by the xylE and araE genes, indicating that all are members of a family of sugar transporters and are related either functionally or evolutionarily. A mechanism for glucose-induced inactivation of maltose transport activity is discussed.
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269
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Gimble JM, Dorheim MA, Cheng Q, Pekala P, Enerback S, Ellingsworth L, Kincade PW, Wang CS. Response of bone marrow stromal cells to adipogenic antagonists. Mol Cell Biol 1989; 9:4587-95. [PMID: 2601690 PMCID: PMC363604 DOI: 10.1128/mcb.9.11.4587-4595.1989] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Adipocytes constitute a major part of the bone marrow stroma in vivo and may play an active role in lymphohematopoiesis. Earlier studies had shown that the bone marrow stromal cell clone BMS2 was capable of adipocyte differentiation in vitro, in addition to its well-defined ability to support B lymphopoiesis. We now demonstrate that the process of adipogenesis in this functional bone marrow stromal cell clone can be inhibited by the cytokines interleukin-1 alpha, tumor necrosis factor, and transforming growth factor beta. Exposure of preadipocyte BMS2 cells to these agents blocked the induction of adipocyte differentiation as assessed by morphologic criteria and analysis of the neutral lipid content. Both interleukin-1 alpha and tumor necrosis factor elicited a rapid transient elevation in the steady-state mRNA levels of c-fos, c-jun, and JE. When added to differentiated adipocytes, the three cytokines continued to act as adipogenic antagonists. This was indicated by concentration- and time-dependent decreases in the activity of an adipocyte-specific enzyme, lipoprotein lipase. These changes in enzyme activity correlated directly with a decrease in steady-state levels of lipoprotein lipase mRNA. Another RNA marker of adipocyte differentiation (adipsin) was less influenced by the adipogenic antagonists. This may reflect the longer half-life of this mRNA transcript compared with those of lipoprotein lipase. Our results dramatically demonstrate that the differentiation state of bone marrow stromal cells can be modulated by exogenous factors in vitro. It is also the first report that transformation growth factor beta regulates the activity of lipoprotein lipase. These data suggest potential physiologic actions for these cytokines in vivo within the overall context of lymphohematopoiesis.
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270
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Del Giudice G, Cheng Q, Mazier D, Meuwissen JH, Grau GE, Corradin G, Pessi A, Verdini AS, Lambert PH. Primary and secondary responses to (NANP) peptides by Plasmodium falciparum sporozoites in various strains of mice. Scand J Immunol 1989; 29:555-62. [PMID: 2471257 DOI: 10.1111/j.1365-3083.1989.tb01158.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The repetitive epitope (Asn-Ala-Asn-Pro = NANP) of the Plasmodium falciparum circumsporozoite protein is considered as the basis for the development of a recombinant or synthetic subunit vaccine against malaria. Vaccines consisting of (NANP)n molecules coupled to carrier proteins have already been tested in trials in human volunteers with partial success. In this paper we show that C57BL/6 mice, genetically responsive to carrier-free (NANP)n molecules, exhibit a secondary antibody response to (NANP) if they are primed with carrier-free (NANP)40 synthetic peptide, and then challenged with P. falciparum sporozoites. However, such a sporozoite-mediated boosting effect is not observed if C57BL/6 and BALB/c mice were previously primed with (NANP)40 peptide conjugated to carrier proteins. The genetic restriction of the murine antibody response to (NANP)n is overcome when mice bearing seven different H-2 haplotypes are immunized with entire P. falciparum sporozoites. These results may have implications for the understanding of natural or induced anti-sporozoite immunity, and show that the use of T-cell epitopes from the plasmodial antigenic repertoire would be very likely to represent an efficient approach for the development of a subunit malaria vaccine.
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271
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Zhu SM, Cheng Q, Hu XZ, Peng CZ. [Comparison of several methods for determination of nitrendipine]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 1988; 23:527-31. [PMID: 3218524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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272
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Del Giudice G, Cheng Q, Mazier D, Berbiguier N, Cooper JA, Engers HD, Chizzolini C, Verdini AS, Bonelli F, Pessi A. Immunogenicity of a non-repetitive sequence of Plasmodium falciparum circumsporozoite protein in man and mice. Immunol Suppl 1988; 63:187-91. [PMID: 2450833 PMCID: PMC1454514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
In the present work, the hypothesis that individuals naturally exposed to Plasmodium falciparum malaria infection in endemic areas produce antibodies directed against non-repetitive epitopes of the circumsporozoite protein was investigated. Using a synthetic peptide reproducing the non-repetitive group-conserved region I sequence, we have shown that specific anti-region I antibodies are detectable in sera from endemic countries. Of these sera, 87% also had antibodies against the immunodominant repetitive epitope (Asn-Ala-Asn-Pro, NANP) of P. falciparum. In order to study the immunogenicity of this non-repetitive epitope, a synthetic peptide consisting of both region I and three (NANP) repeats [RI-(NANP)3] was used to immunize inbred strains of mice. H-2b mice produced antibodies against both the repetitive and the non-repetitive epitope. These antibodies were specific for each epitope, recognized P. falciparum sporozoites in immunofluorescence, and inhibited sporozoite penetration into human liver cells in vitro. Non-H-2b mice were completely unresponsive. Lymph node cells from H-2b mice immunized with RI-(NANP)3 peptide proliferated in the presence of RI-(NANP)3 and of (NANP)4 peptide, but never in the presence of RI peptide alone. These findings demonstrate that in the configuration used (i) the non-repetitive epitope region I does not carry T-helper epitopes; (ii) the (NANP) repetitive epitope may act as a carrier for the immune response to region I in mice; and (iii) therefore, immune response to region I in man probably depends on the recognition of T-cell epitopes similar to those involved in the anti-NANP response: i.e. such a T epitope may be NANP itself in responding individuals or another, not yet recognized, sporozoite T-cell epitope.
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