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Mansoor N. Saleh Albert F. LoBuglio Richard H. Wheeler Kimberly J. Rogers Amy Haynes Jeannette Y. Lee M. B. Khazaeli 《Cancer immunology, immunotherapy : CII》1990,32(3):185-190
Summary A group of 15 patients with metastatic colorectal adenocarcinoma received a combination of interferon (0.1 mg/m2, days 1–15) and the murine monoclonal antibody 17-1A (400 mg, days 5, 7, 9 and 12). The treatment was tolerated with minimal toxicity. Of the 14 evaluable patients, 13 developed human antibody to murine 17-1A, with 11 patients demonstrating antibody to the variable region of 17-1A (anti-idiotype). Antibody to the variable region was inhibited by 17-1A but not by mouse immunoglobulin. Sera from patients with substantial anti-idiotype reactivity were capable of inhibiting the binding of murine 17-1A to antigen expressing LS174-T cells thus indicating the presence of antibody directed against the 17-1A combining site (mirror-image anti-idiotype). The median survival of the whole group was 56 weeks and there was no correlation between clinical response/survival and the development of anti-idiotype antibody.Supported by the Veterans Administration Medical Center and by Public Health Services grant CA 45 232 from the National Cancer Institute, National Institutes of Health, Department of Health and Human Services 相似文献
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Aerial Dispersal and Epiphytic Survival of Pseudomonas syringae during a Pretest for the Release of Genetically Engineered Strains into the Environment 总被引:15,自引:15,他引:0 下载免费PDF全文
Steven E. Lindow Guy R. Knudsen Ramon J. Seidler Michael V. Walter Victor W. Lambou Penny S. Amy David Schmedding Valerie Prince Stephen Hern 《Applied microbiology》1988,54(6):1557-1563
Prospective experimental field evaluation of genetically engineered microorganisms, such as microbial pest control agents, raises issues of how to properly ascertain their fate and survival in the environment. Field trials with recombinant organisms must reflect requirements for sampling and monitoring. Field trials were conducted at Tulelake, Calif., to monitor the numbers of viable cells of a nonrecombinant strain of Pseudomonas syringae that entered the atmosphere and landed on plants and soil during and after an aerosol spray application. An exponential decrease in numbers of viable cells deposited at increasing distances from three sprayed plots was observed. The relative rate of survival of cells sprayed directly on plants was more than 10 times higher than that of cells dispersed through the air to similar adjacent plants. Results are being used to gain experience with the characteristics of a release site that influence containment or dispersal and to develop appropriate sampling methodologies for evaluating survival and dispersal characteristics of genetically engineered bacteria released into the environment. The ability to make predictions about microbial dispersal and survival will reduce the uncertainties associated with environmental releases of recombinant organisms. 相似文献
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Cultured promastigote and isolated amastigote forms of Leishmania mexicana mexicana have been surveyed for the presence of enzymes involved in purine metabolism. Quantitative but not qualitative differences between the enzymes of two forms were discovered. There were found to be significant differences between the enzyme content of L. m. mexicana and that reported for L. donovani. Extracts of both parasite forms of L. m. mexicana were found to have higher levels of adenine deaminase (EC 3.5.4.2) and guanine deaminase (EC 3.5.4.3) than adenosine deaminase (EC 3.5.4.4). There appeared to be two distinct nucleosidases (EC 3.2.2.1), one active on nucleosides, the other on deoxynucleosides. Phosphorylase (EC 2.4.2.1) could be detected only in the catabolic direction. Nucleotidases were present, but were more active on 3' (EC 3.1.3.6)- than 5' (EC 3.1.3.5)-nucleotides. Phosphoribosyltransferase (EC 2.4.2.7,.8 and .22) and nucleoside kinase (EC 2.7.1.20) activities were detected in both forms. Nucleotide-interconverting enzymes were found to be present, with IMP dehydrogenase (EC 1.2.1.14) being the most active. Cell fractionation experiments revealed that, in the promastigote, enzyme separation within the parasite may play an important part in regulating cellular purine metabolism. 相似文献
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Evidence is presented of the ability of H-2 class I antigens to function as teratocarcinoma transplantation (Gt) antigens. Coisogenic immunization against H-2 class I antigens expressed on transfected L cells is shown to induce resistance to embryonic carcinoma (EC) cell allografts. The Kb, Db, Dd, and, in appropriate recipients, Ld antigens can function as Gt antigens. The protocol presented may be useful for the molecular identification of other genes encoding histocompatibility antigens. 相似文献
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J M Frazier S S George J Overnell T L Coombs J Kagi 《Comp. Biochem. Physiol. C, Comp. Pharmacol. Toxicol.》1985,80(2):257-262
Inducible cadmium binding proteins (Cd-BP) in the mussel, Mytilus edulis, were resolved into two molecular weight components by gel permeation chromatography on Sephadex G-75. Each of these two molecular weight components was further resolved into four subcomponents by DEAE ion exchange chromatography. All eight subcomponents bound cadmium and exhibited significant u.v. absorption at 254 and little absorption at 280 nm. Based on amino acid composition analysis two classes of proteins were identified, one having higher cysteine (approximately 25 mole %) and lower serine and glutamic acid contents compared to the other class. 相似文献
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We have reconstituted pigment-protein complexes isolated from Rhodopseudomonas palustris photosynthetic membranes into phospholipid liposomes. The various complexes were tested for their ability to promote adhesion of the liposome membrane in the presence and absence of Mg2+ ions. Samples containing a reaction center (RC)/light-harvesting I (LHI) complex appeared to stack in a manner resembling control thylakoids in 2 and 5 mM Mg2+. We also tested for the effects of Mg2+ on detergent extractablity of pigment-protein complexes from intact membranes. Mg2+ sharply reduced the amount of LHI solubilized from membranes, while having little effect on the extractability of the light harvesting II complex (LHII) and the RC. Based on these results we suggest that LHI is the principal adhesion factor of R. palustris thylakoids.Abbreviations LHC
light harvesting complex
- OG
octyl glucoside
- RC
reaction center
This paper is dedicated to Professor G. Drews on the occasion of his 60th birthday 相似文献
30.
Role of protein synthesis in the survival of carbon-starved Escherichia coli K-12. 总被引:27,自引:11,他引:16 下载免费PDF全文
In a typical Escherichia coli K-12 culture starved for glucose, 50% of the cells lose viability in ca. 6 days (Reeve et al., J. Bacteriol. 157:758-763, 1984). Inhibition of protein synthesis by chloramphenicol resulted in a more rapid loss of viability in glucose-starved E. coli K-12 cultures. The more chloramphenicol added (i.e., the more protein synthesis was inhibited) and the earlier during starvation it was added, the greater was its effect on culture viability. Chloramphenicol was found to have the same effect on a relA strain as on an isogenic relA+ strain of E. coli. Addition of the amino acid analogs S-2-aminoethylcysteine, 7-azatryptophan, and p-fluorophenylalanine to carbon-starved cultures to induce synthesis of abnormal proteins had an effect on viability similar to that observed when 50 micrograms of chloramphenicol per ml was added at zero time for starvation. Both chloramphenicol and the amino acid analogs had delayed effects on viability, compared with their effects on synthesis of normal proteins. The need for protein synthesis did not arise from cryptic growth, since no cryptic growth of the starving cells was observed under the conditions used. From these and previous results obtained from work with peptidase-deficient mutants of E. coli K-12 and Salmonella typhimurium LT2 (Reeve et al., J. Bacteriol. 157:758-763, 1984), we concluded that a number of survival-related proteins are synthesized by E. coli K-12 cells as a response to carbon starvation. These proteins are largely synthesized during the early hours of starvation, but their continued activity is required for long-term survival. 相似文献