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1.
Summary We compared the ability of murine lymphokine-activated killer (LAK) cells grown in either a serum-supplemented standard medium (MEM plus fetal calf serum) or a serum-free medium (AIM-V) to lyse a range of tumour targets. LAK cells grown in either of the media killed a cultured murine tumour line (YAC-1 lymphoma) well and spared syngeneic self cells (concanavalin-A-stimulated splenocytes). However, a striking difference was noted in the ability of LAK cells grown in MEM plus fetal calf serum (as opposed to AIM-V) to kill modified self cells (trinitrophenol-modified concanavalin A blasts); LAK cells grown in the former always killed modified self cells better than those grown in the latter. This pattern held under a broad range of experimental manipulations and was found to be related to a relative increase in CD3-bearing LAK cells grown in the standard medium. These data suggest that the two media cannot be used interchangeably. This conclusion may have clinical implications for the use of LAK cells, as animal studies have been done using LAK cells generated in serum-containing medium and clinical studies have used LAK cells generated in serum-free medium.  相似文献   

2.
In the present report, we used serological, cellular, and restriction fragment length polymorphism (RFLP) to investigate the DR1 haplotype in the Israeli population. We describe an Israeli homozygous typing cell (HTC), HLA-DwLVA, which defines a new lymphocyte-activating determinant associated with Bw65, DR1 and distinct from Dwl. The parents of this donor, non-Ashkenazi Algerian Jews, are first cousins and share HLA-Cw8, Bw65, BfS, DR1, DQw1, DPw4. No specificity could be assigned to HLA-DwLVA using the 91 Ninth Workshop HTCs. Two families and forty unrelated DR1 individuals were studied with DwLVA and a panel of DR1/Dw1 HTCs. HLA-DwLVA showed segregation as a single determinant within families. This new specificity was present in 24 out of 40 (60%) unrelated DR1 individuals, indicating that in the Israeli population DwLVA is the main lymphocyte-defined determinant associated with the serologically defined DRI specificity, in contrast to non-Jewish Caucasoids where DR1 is significantly associated with Dw1. The vast majority of DwLVA-positive carriers were also Bw65 carriers, indicating that Bw65, DR1, DwLVA may represent a typical allele combination in the Israeli population. The RFLP analysis established the correlation of certain RFLPs with Dw1 and DwLVA. In addition, we describe a cluster of RFLPs that may correspond to a new Dw subtype associated with DR1, for which no serological and cellular reagents have been described so far.  相似文献   

3.
Incubation of synthetic Man\1-4GlcNAc-OMe, GalNAc1-4GlcNAc-OMe, Glc1-4GlcNAc-OMe, and GlcNAc1-4GlcNac-OMe with CMP-Neu5Ac and rat liver Gal1-4GlcNAc (2-6)-sialyltransferase resulted in the formation of Neu5Ac2-6Man1-4GlcNAc-OMe, Neu5Ac2-6GalNAc1-4GlcNAc-OMe, Neu5Ac2-6Glc1-4GlcNAc-OMe and Neu5Ac2-6GlcNAc1-4GlcNAc-OMe, respectively. Under conditions which led to quantitative conversion of Gal1-4GlcNAc-OEt into Neu5Ac2-6Gal1-4GlcNAc-OEt, the aforementioned products were obtained in yields of 4%, 48%, 16% and 8%, respectively. HPLC on Partisil 10 SAX was used to isolate the various sialyltrisaccharides, and identification was carried out using 1- and 2-dimensional 500-MHz1H-NMR spectroscopy.Abbreviations 2D 2-dimensional - CMP cytidine 5-monophosphate - CMP-Neu5Ac cytidine 5-monophospho--N-acetylneuraminic acid - COSY correlation spectroscopy - DQF double quantum filtered - HOHAHA homonuclear Hartmann-Hahn - MLEV composite pulse devised by M. Levitt - Neu5Ac N-acetylneuraminic acid - Neu5Ac2en 2-deoxy-2,3-didehydro-N-acetylneuraminic acid  相似文献   

4.
Summary The ultrastructural localization of nicotinamide adenine dinucleotide phosphatase (NADPase) in bovine Leydig cells has been studied and compared with the pattern of thiamine pyrophosphatase (TPPase) and acid phosphatase distribution in these cells. Using -nicotinamide adenine dinucleotide phosphate (-NADP+) as substrate, a marked staining is observed in the intermediate Golgi saccules with some focal extension to the trans aspect. Cisternae on the cis side and associated vesicles yielded only slightly positive reactions. The pattern of NADPase localization is clearly different from that of TPPase which consistently stains only the trans Golgi elements. The specifity of NADPase for its substrate, -NADP+, was clearly demonstrated by using substrates modified in either the nicotinamide region e.g. -nicotinamide adenine dinucleotide phosphate (-NADP+), -thionicotinamide adenine dinuclcotide phosphate (Thio-NADP+), in the attachment site of the monoester phosphate group to the molecule (e.g. 2 monophospho-adenosine 5-diphosphoribose (ATP-ribose) or adenosine-5-monophosphate (5AMP). With these substrates only weak or negative reactions were obtained in the Golgi apparatus of the bovine Leydig cell.  相似文献   

5.
The mechanisms of lysis of endothelial cells derived from human umbilical vein (HUVEC) by autologous lymphokine-activated killer (LAK) cells, generated from cord blood lymphocytes of the same donor, were investigated. Freshly isolated HUVEC as well as HUVEC cultured for several passages were efficiently lysed by autologous LAK cells, and their susceptibility to the LAK cells was almost the some as that of allogenic HUVEC. Complement-depletion experiments revealed that the lysis was mainly dependent on CD16-natural killer (NK) LAK cells. Pretreatment of HUVEC with recombinant interferon (rIFN) for 24 h made them resistant to lysis by autologous LAK cells, while pretreatment with either rIL-1. rTNF, or acidic or basic fibroblast growth factor did not alter the lytic sensitivity of HUVEC. The resistance of rIFN-treated HUVEC was specific to lysis by CD16+ NK LAK cells, and their lysis by CD3+ T-LAK cells was not significantly altered. Moreover, in comparison with control HUVEC or rIL-1-treated HUVEC, rIFN-treated HUVEC had a significantly less potent inhibitory effect on the lysis of untreated HUVEC, when used as an unlabeled target. This suggests that rIFN treatment may down-regulate the recognition of some molecules on HUVEC by rIL-2-activated NK cells. These data suggest that damage of the endothelium during LAK therapy is mainly dependent on LAK cells with a NK phenotype that can specifically recognize a certain molecule on autologous endothelial cells.  相似文献   

6.
Summary Incubation of human lymphocytes with recombinant interleukin-2 (rIL-2) results in the generation of lymphokine-activated killer (LAK) cells capable of lysing a wide variety of tumor cells. The present study was undertaken to examine the effect of recombinant interferon (rIFN-) on LAK cell cytotoxicity generated from different peripheral blood mononuclear cell (PBMC) subpopulations. When unseparated PBMC were stimulated by rIL-2 and rIFN-, the latter induced a transient enhancement after 2 days followed by a suppression of LAK cell cytotoxicity at day 6. Enhancement of LAK cell cytotoxicity was moderate and inconstant, whereas the inhibition was strong and observed with all the donors tested. This suppression was not associated with a decrease in the [3H]thymidine uptake. PBMC depleted of adherent cells were more sensitive to the stimulation by rIL-2 and the induced cytotoxicity was not modified by rIFN-. Monocyte-enriched plastic-adherent cells, when incubated with rIL-2 and rIFN-, became cytotoxic after 2–3 days of culture and inhibited LAK cell activity after 5–6 days. Collectively, our results suggest that rIFN- affects LAK cell cytotoxicity through the activation of plastic-adherent, monocyte-rich, cells which modulate natural killer cells, first in a positive, then in a negative way.  相似文献   

7.
Summary Nocardia rubra cell wall skeleton (N-CWS) was found to synergistically augment lymphokine-activated killer (LAK) cell generation from human peripheral blood mononuclear cells (PBMC) in the presence of a suboptimal dose of recombinant interleukin-2 (rIL-2). N-CWS increased the number of PBMC expressing IL-2 receptor on their surfaces, and the presence of N-CWS at the early stage of the culture period was essential for the exertion of its augmentative activity on the LAK induction. The predominant phenotype of LAK precursor cells responding to N-CWS and rIL-2 was CD3 CD16+. Culture supernatant from N-CWS-stimulated PBMC was found to act as a substitute for N-CWS in the induction of LAK generation in the presence of rIL-2, suggesting that these cells produced a factor capable of augmenting LAK cell induction (LAK helper factor, LHF). LHF was found to have a molecular mass of 29 kDa by gel filtration, and could also function as a killer helper factor to augment allo-antigen-specific cytotoxic T lymphocyte generation from human peripheral blood T cells as well as murine thymocytes. LHF showed no species specificity, indicating that it is different from IL-4. The enhancing activity of LHF was not neutralized with anti-TNF, anti-IL-1, or anti-IL-1 antibodies. Furthermore, no tumor necrosis factor- (TNF), TNF, IL-1, , IL-2, IL-5, IL-6 or interferon activity was detected in semi-purified LHF during enzyme-linked immunosorbant assay and biological assays. The present findings indicate that LHF produced from N-CWS-stimulated PBMC is a molecule distinct from TNF, TNF, interferon, IL-1, -2, -4, -5, and -6, and suggest that LHF might be a novel lymphokine involved in LAK generation.This work was supported by a Grant-in-aid for Cancer Research from the Ministry of Education, Science, and Culture of Japan  相似文献   

8.
The insulin-producing pancreatic islet -cell, characterized by low proliferative potential, is normally not responsive to the polypeptide epidermal growth factor (EGF) or its homolog transforming growth factor (TGF-). Since EGF receptors in other tissues can be up-regulated by other growth factors and by cytokines, we have in this paper investigated whether such a -cell responsiveness to TGF-, or EGF, can be conferred by co-culture with interferon (IFN-), tumor necrosis factor (TNF-) or transforming growth factor (TGF-) in various combinations. To this end, fetal rat pancreatic islets enriched in -cells were isolated and cultured for 3 days with or without 200 pM or 20 nM TGF-. It was found that neither of these TGF- concentrations affected -cell mitogenesis, insulin content or insulin secretion. However, IFN- (1000 U/ml) evoked a modest stimulation of -cell replication, while suppressing insulin secretion and leaving the islet insulin content unaltered. TNF- (1000 U/ml), on the other hand, affected none of these parameters either alone or in any combination with TGF- or IFN-. However, when TNF- or IFN-, either alone or in combination, were combined with the cytokine interleukin-1, this resulted in islet disintegration, whereas the latter cytokine alone did not exert any gross necrotic changes evident by light microscopy. TGF- (500 pM) stimulated insulin secretion but did not influence islet insulin content or -cell mitogenesis either alone or in combination with TGF- (200 pM or 20 nM). In no instance could any mitogenic or secretory response to low or high concentrations of TGF- be conferred by IFN-, TNF- or TGF- whether used alone or in combinations. Hence, responsiveness to TGF- or EGF in the -cell obviously cannot be achieved by any of these peptides.Abbreviations EGF epidermal growth factor - IFN- interferon - TGF- transforming growth factor - TGF- transforming growth factor - TNF- tumor necrosis factor   相似文献   

9.
Summary A mutant strain of Rhodococcus equi accumulates three metabolites from the androst-4-ene-3,17-dione or from its degradation intermediate, 3a-H-4(3'-propionic acid)-7a-methylhexahydro-1,5-indanedione (MEPHIP). These three metabolites are: 3a-H-4a(3'-propionic acid)-5-hydroxy-7a-methylhexahydro-1-indanone--lactone (HIL); 3a-H-4(3'-trans acrylic acid)-5-hydroxy-7a-methylhexahydro-1-indanone (2'-5-hydroxy-MEPHIP); and 3a-H-4(3'-hydroxy-3'-propionic acid)-5-hydroxy-7a-methylhexahydro-1-indanone (3'-hydroxy-HIL). The behaviour of this mutant allows us to propose a pathway for degradation of the intermediates, methylperhydroindanone propionates. However, during this degradation, the side-chain propionate was eliminated by a-oxidation mechanism. Offprint requests to: A. Miclo  相似文献   

10.
Pseudomonas maltophilia is an uncommon cause of hospital-acquired infection and is resistant to most of the antimicrobial agents used in the treatment of gram-negative infections. Susceptibility of 108 isolates ofP. maltophilia to ceftazidime, aztreonam, defpirome, gentamicin, imipenem, enoxacin, and ticarcillin plus clavulanic acid was determined by an agar dilution method. The isolates were in general resistant to the antibiotics. Imipenem and cefpirome were not active at clinically achievable levels. Of the isolates, 20% were susceptible to 16 g/ml ceftazidime, 53% were susceptible to 4 g/ml enoxacin, 10% were susceptible to 4 g/ml gentamicin, and 25% were susceptible to 64 g/ml ticarcillin plus 2 g/ml clavulanic acid.  相似文献   

11.
Summary We recently reported that interleukin-2(IL-2)-activated peripheral blood lymphocytes and CD3+, lymphokine-activated killer (LAK) cell clones release tumor necrosis factor (TNF) and interferon (IFN) when stimulated with K562 erythroleukemia cells. We examined the phenotype of IL-2-activated peripheral blood leukocytes that secrete TNF and IFN when stimulated with K562 cells and demonstrated that TNF secretion is not due to the presence of contaminating mononuclear phagocytes. Further, we demonstrate that IL-2-activated natural killer (NK) cells release only IFN when stimulated with K562 cells while T lymphocytes exposed to monoclonal anti-CD3 and K562 cells secrete both TNF and IFN. However, T cells stimulated only with K562 cells did not release IFN or TNF while the admixture of these T cells with NK cells, when stimulated with K562 cells, released levels of TNF comparable to those produced by the unseparated cells. At present it is unclear whether only one or both effector cell types respond to K562 by releasing TNF or why the presence both cell types is needed.This work was supported by grants from the national Institutes of Health (CA 23074 and CA 17094) and the Arizona Disease Commission (8277-000000-1-0-YR-9301)  相似文献   

12.
    
In this investigation, an overlapping set of synthetic peptides spanning the entire primary structures of the -subunit of bovine and human thyrotropin, bTSH and hTSH respectively, have been prepared to aid the delineation of the amino acid sequence regions involved in two spatially related epitopes of bTSH. These peptides were then evaluated for their ability to inhibit the binding of two anti-hTSH monoclonal antibodies, designated mAb279 and mAb299, to radiolabeled I125-bTSH using competitive radioimmunoassay procedures. Synthetic peptides related to the sequence region b/hTSH[56–68] were found to specifically inhibit the binding of I125-bTSH to mAb299, whilst having no effect on the binding of mAb279. In previous studies we have shown that mAb279 and mAb299 recognise epitopic sites located within the receptor-binding site of the TSH -subunit. This investigation has therefore permitted identification of a contribution to the receptor binding site from the TSH[56–68] sequence, which forms part of the L3 loop region of the TSH -subunit that is held in close proximity to the L1 loop region and the C-terminus of the TSH - subunit by the disulphide bonds TSH[Cys16- Cys67] and TSH[Cys19-Cys105]. This finding is in agreement with previous investigations which have shown that TSH[Tyr59] and TSH[Tyr74] are also associated with the mAb299 epitope site, as well as contributing to the receptor binding region of the TSH -subunit.  相似文献   

13.
Summary Cytokinesis in the unicellular chlorococcalean alga Eremosphaera viridis de Bary has been investigated by electron microscopy of thin sections. The new plasmalemmata of the daughter cells in this organism form centrifugally within a phycoplast. Unlike other cell division systems each new plasmalemma is formed, not by the fusion of vesicles, but rather by the fusion of open membranes which are characteristically heavily stained. Measurements of these open membranes reveal that they are 11 nm thick with a central 4,5 nm unstained portion. The possible origin of these open membranes as burst-open vesicles has been suggested from the presence of intensely straining vesicles in the vicinity of the cell equator. Calculations of vesicle and open membrane surface areas support this contention.  相似文献   

14.
Biology cannot accommodate all aspects of culture. Aspects of culture that a biological approach can take into account can be covered by the biological categories of phenotype and environment. There is no need to treat culture as a separate category. Attempts to elaborate biological explanations of cultural variation will meet with success only if biologists expand theories of development, and integrate them in evolutionary biology. The alternative — elaborating the idea of so-called cultural inheritance — makes little sense from a biological point of view.  相似文献   

15.
Summary Electron-microscopic studies of plastids in cortical cells of poplar (Populus euramericana cv. gelrica) were carried out to examine whether any structural changes were initiated after breaking of dormancy in midwinter under non-growing conditions. After the breaking of dormancy, ultrastructural changes became evident and the profiles of plastids became heterogeneous. Organelles resembling the plastid initials proposed by Mühlenthaler and Frey-Wyssling in 1965 were frequently observed concomitant with changes in the plastid envelope. The formation of plastid initials appeared to be initiated by the formation of septa in pre-existing plastids. After this stage, narrow connections appeared between the initials and the parent plastids. Approximately 50 days after the breaking of dormancy in late March, further heterogeneity in the profiles of plastids was observed. At this stage, young plastids (plastids without starch granules) were frequently observed and the formation of plastid initials was hardly ever observed. These observations suggest that the plastid initials may be present for only a limited period in the cortical cells of the poplar and may be the precursors of the proplastids. Similar ultrastructural profiles were found in cortical cells of mulberry and in leaf buds of apple trees, suggesting that such changes in the ultrastructure of plastids are a general feature of perennials.  相似文献   

16.
    
Summary As has been shown previously, RNA polymerase subunit ts-mutation rpoC1 results in an overproduction of RNA polymerase subunits at nonpermissive temperature. The mutant enzyme shows low activity in vitro and a sedimentation coefficient 9S which is characteristic of immature core polymerase. In this paper we describe a mutation designated opr1 which suppresses RNA polymerase subunit overproduction. The mutation was found among Ts+ revertants of the Ts double mutant carrying a rpoC1 mutation and a rif-r rpo B251 mutation. Opr1 is closely linked to the original rpo mutations and shows complete trans-dominance. Although opr1 seems to affect RNA polymerase, it does not suppress the accumulation of immature 9S RNA polymerase and does not restore the activity of the RpoC1 mutant enzyme. This and other results of a comparison of strains carrying different combinations of rpoC1, rpoB251 and opr1 mutations suggest that neither inhibition of total RNA and protein synthesis, nor the low RNA polymerase activity in vitro, nor the apparent defects in enzyme maturation, nor the enzyme degradation observed at 42°C are responsible for the overproduction in RpoC1 strains.  相似文献   

17.
Summary Most cell wall components are carbohydrate including the major matrix polysaccharides, pectins and hemicelluloses, and the arabinogalactan-protein proteoglycans. Both types of molecules are assembled in the Golgi apparatus and transported in secretory vesicles to the cell surface. We have employed antibodies specific to -(16) and -(14)-D-galactans, present in plant cell wall polysaccharides, in conjunction with immunofluorescence and electron microscopy to determine the location of the galactan-containing components in the cell wall and Golgi stacks of flax root tip tissues. Immunofluorescence data show that -(14)-D-galactan epitopes are restricted to peripheral cells of the root cap. These epitopes are not expressed in meristematic and columella cells. In contrast, -(16)-D-galactan epitopes are found in all cell types of flax roots. Immunogold labeling experiments show that both epitopes are specifically located within the wall immediately adjacent to the plasma membrane. They are also detected in Golgi cisternae and secretory vesicles, which indicates the involvement of the Golgi apparatus in their synthesis and transport. These findings demonstrate that the synthesis and localization of -(14)-D-galactan epitopes are highly regulated in developing flax roots and that different -linked D-galactans associated with cell wall polysaccharides are expressed in a cell type-specific manner.  相似文献   

18.
Summary We have investigated the endogenous production of a serum cytotoxic factor when recombinant interferon- (rIFN-) is combined with synthetic lipid A subunit analogs of low toxicity (GLA compounds). The cytotoxic activity of the serum was measured by the crystal violet staining method with L929 cells as a target. Intravenous administration of rIFN- followed by intravenous administration of lipopolysaccharide induced the endogenous production of a cytotoxic factor in the serum. The priming effect of rIFN- appeared immediately and persisted for approximately 20 h after the injection. Administration of lipopolysaccharide as a trigger enhanced the production of the cytotoxic factor in the serum maximally 2 h after the injection. The cytotoxic activity in the serum was completely inhibited by anti-(mouse tumor necrosis factor) (TNF) antibody. A synthetic lipid A subunit analog (GLA-60), which is much less toxic in its endotoxin activities than lipopolysaccharide or synthetic lipid A (compound 506), induced the endogenous production of serum TNF in rIFN--primed mice. GLA-60 entrapped within liposomes induced the production of serum TNF in rIFN--primed mice more effectively than GLA-60 solubilized in phosphate-buffered saline. Intravenous or intranasal administrations of rIFN- followed by intranasal administration of GLA-60 produced TNF in the lung washing fluid but not in the serum, indicating that TNF production can be induced locally rather than systemically by the alteration of the administration route of the primer and trigger. These results indicate that GLA-60, a lipid A subunit analog of low toxicity, is a beneficial triggering agent in the production of endogenous TNF, as well as having other immunopharmacological properties, and may provide a basis for cancer (metastases) treatment as a result of its ability to induce endogenous TNF.  相似文献   

19.
We investigated the influence of the combined use of sizofiran, a-1,3-glucan and a recombinant interferon- (rIFN-) upon biological activities of peritoneal macrophages (M). The number of peritoneal M and the production of cytokines (interleukin-1, interferon- and tumor necrosis factor) was increased by the combined treatment. Fully activated peritoneal M based on the increased number of elongated pseudopods were observed by electromicroscope. Sizofiran seems to assure a sufficient supply of M to kill tumor cells in the peritoneal cavity and co-administered rIFN- seems to directly stimulate the accumulated M in addition to its direct cytotoxicity against tumor cells. This combination therapy may be a step to the prevention of the recurrence of gynecological malignancies including ovarian cancer, after a negative second-look laparotomy.Abbreviations rIFN- recombinant interferon- - IL-1 interleukin-1 - TNF tumor necrosis factor - SLL second look laparotomy  相似文献   

20.
Summary The specificity analysis of a CD3+, WT31+, CD8+ cytotoxic T lymphocyte (CTL) clone (CTL 49), isolated from peripheral blood lymphocytes of a melanoma patient (no. 665) after mixed lymphocyte culture with an HLA-A2+ allogeneic lymphoblastoid cell line (VSKB-LCL), revealed that CTL 49 could lyse, in addition to HLA-A2+ lines, autologous HLA-A2 melanoma (Me665/2) and K562 targets. Killing of VSKB-LCL, but not of Me665/2, could be inhibited by anti-CD3 and by anti-HLA-A2 antibodies or by modulation of the CD3 complex. Cold-target competition studies showed that K562, but not VSKB-LCL, could compete with Me665/2 for lysis by CTL 49. However, unlike K562, Me665/2 could be lysed by CTL 49 in a Ca2+-independent fashion in 4 h and 18 h assays. CTL 49 expressed mRNA specific for tumor necrosis factor (TNF) and, to a lesser extent, for lymphotoxin (TNF). Exposure of the clone to anti-CD3 antibodies induced the expression of interferon(IFN)--specific and the up-regulation of TNF- and TNF-specific mRNA. Antibodies to TNF, TNF and IFN reduced the lysis of Me665/2, but not of K562, by CTL 49 in 18-h cytotoxic assays. Antibodies to TNF and to IFN almost completely inhibited the lysis seen on Me665/2 (but not on K562), in 96-h assays, by supernatants isolated from VSKB-LCL- or anti-CD3-stimulated CTL 49 cells. Taken together, these data indicate that major-histocompatibility-complex-independent lysis of autologous tumor cells and of natural killer reference targets by the same alloreactive T cell clone are activities related at the level of target recognition but distinct at the level of the lytic hit. Thus, efficient lysis of autologous tumor cells results from a complex mechanism based upon direct effector-target interaction as well as on cytokine-mediated cytolytic effects.  相似文献   

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