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J E Albina

Publications and source records attributed to J E Albina.

At least 19 recordsLinked to original sources
PubMed2000

TA1/LAT-1/CD98 light chain and system L activity, but not 4F2/CD98 heavy chain, respond to arginine availability in rat hepatic cells. Loss Of response in tumor cells.

Tumor associated gene-1/L amino acid transporter-1 (TA1/LAT-1) was recently identified as a light chain of the CD98 amino acid transporter and cellular activation marker. Our previous studies with primary rat hepatocyte cultures demonstrated that TA1 RNA levels were responsive to media amino acid concentrations, suggesting adaptive regulation. High level TA1 expression associated with transformed cells also suggested a role in tumor progression. The present study examined the relationship of TA1/CD98 expression, adaptive response, and associated amino acid transport to neoplastic transformation using a panel of well characterized rat hepatic cell lines. We found 1) increased expression of TA1 in response to amino acid depletion, specific for arginine but not glutamine; 2) loss of TA1 response to arginine in gamma-glutamyl transpeptidase-positive transformed and tumorigenic cells; 3) no appreciable response of 4F2/CD98 heavy chain to arginine levels; and 4) correlation of system L amino acid transport activity in response to arginine with changes in TA1/LAT-1 mRNA but not total immunoreacting protein. Our results suggest this CD98 light chain may act as an environmental sensor, responding to amino acid availability and that its regulation is complex. We hypothesize that altered TA1 expression is an early event in hepatocarcinogenesis giving neoplastic cells a growth or survival advantage, particularly under conditions of limited amino acid availability.

Amino Acid Transport Systems↗
PubMed1999

Acyl phosphatase activity of NO-inhibited glyceraldehyde-3-phosphate dehydrogenase (GAPDH): a potential mechanism for uncoupling glycolysis from ATP generation in NO-producing cells.

Treatment of glyceraldehyde-3-phosphate - dehydrogenase (GA (GAPDH) with the NO donors S-nitrosoglutathione, 3-morpholinosydnonimine or diethylamine NONOate (diethylamine diazeniumdiolate) in vitro, inhibited its dehydrogenase activity and induced its acyl phosphatase activity. NO-producing cells, in turn, exhibited reduced GAPDH activity, increased glycolysis, and decreased ATP content, synthesis and turnover. These cellular alterations could be explained by the uncoupling of glycolytic flux from substrate level phosphorylation by the acyl phosphatase activity of NO-modified GAPDH.

Adenosine Triphosphate↗
PubMed1999

Promotion of neutrophil chemotaxis through differential regulation of beta 1 and beta 2 integrins.

Migration of neutrophils requires sequential adhesive and deadhesive interactions between beta 1 and beta 2 integrins and components of the extracellular matrix. Prompted by reports that describe interaction of soluble beta-glucan with the beta 2 integrin Mac-1, a role for beta-glucan in regulation of integrin-mediated migration was investigated. Neutrophil migration in response to fMLP was assessed using an agarose overlay method with slides precoated with fibronectin (Fn) +/- beta-glucan. On Fn, random migration in excess of directed migration was observed. In contrast, migration on Fn + beta-glucan was directional, with marked diminution of random migration. This conversion of random to directed migration was seen neither when Fn was supplemented with alternative polysaccharides nor when beta-glucan was applied to other components of the extracellular matrix. This effect of beta-glucan was shown to be cation dependent and to be effected by Arg-Gly-Asp-containing peptides consistent with an integrin-mediated event. mAb inhibition studies demonstrate that beta-glucan effects this shift toward directed migration through suppression of migration mediated by Mac-1 and very late Ag 5 and enhancement of very late Ag 3-mediated migration. Adhesion assays suggest that the prochemotactic influence of beta-glucan is due, in part but not entirely, to modulation of PMN adhesion to Fn. In summary, these data support a novel role for beta-glucan in regulation of beta 1- and beta 2-mediated neutrophil migration on Fn.

Antibodies, Monoclonal↗
PubMed1999

Macrophage phagocytosis of wound neutrophils.

Resolution of acute inflammation is thought to require the recognition and phagocytosis of apoptotic neutrophils (PMN) through receptor-ligand interactions with macrophages (Mphi). This hypothesis was tested in rat wounds by quantifying apoptosis in freshly harvested and aged-in-culture PMN taken from wounds 1-3 days after injury and by using these wound PMN as phagocytic targets for wound, immune-activated peritoneal, and resident peritoneal Mphi. Less than 6% of freshly harvested PMN exhibited characteristics of apoptosis. On aging in culture, day 1 PMN did not undergo apoptosis, whereas 41+/-1 and 29+/-1% of day 2 and 3 PMN, respectively, developed apoptosis, which corresponded to increased ingestion by Mphi. All three Mphi populations engaged different receptor-ligand pairs for the recognition and phagocytosis of PMN. Results indicate the resistance of early wound PMN to age-induced apoptosis, demonstrate wound-Mphi phagocytosis of wound PMN, and identify distinct receptor utilization by wound and other Mphi to ingest wound PMN.

Animals↗
PubMed1999

Molecular and metabolic evidence for the restricted expression of inducible nitric oxide synthase in healing wounds.

Tissue injury initiates a temporally ordered sequence of local cellular and metabolic responses presumably necessary for successful repair. Previous investigations demonstrated that metabolic evidence for nitric oxide synthase (NOS) activity is detectable in wounds only during the initial 48 to 72 hours of the repair process. Present results identify the cell types contributing inducible NOS (iNOS) to experimental wounds in rats. iNOS antigen was expressed in most macrophages present in wounds 6 to 24 hours after injury, and these cells exhibited NAPDH diaphorase and NOS activity. Polymorphonuclear leukocytes contained little iNOS antigen and no NADPH diaphorase activity and were minimally able to convert L-arginine to L-citrulline. The frequency of iNOS-positive macrophages declined on days 3 and 5 after wounding. By day 10, most macrophages in the wound were negative for iNOS. These cells, however, acquired iNOS antigen and activity in culture. Wound fluids, but not normal rat serum, suppressed the induction of iNOS during culture. Findings indicate that the expression of iNOS in healing wounds is restricted to macrophages present during the early phases of repair and that components of wound fluid suppress the induction of iNOS in macrophages in late wounds. Polymorphonuclear leukocytes contribute little iNOS activity to the healing wound.

Animals↗
PubMed1999

Regulation of arginase isoforms I and II by IL-4 in cultured murine peritoneal macrophages.

Macrophages can express two arginase isoforms with distinct subcellular localization (cytosolic AI and mitochondrial AII). These isoforms are products of different genes and are capable of differential induction. Experiments were performed to identify the specific arginase isoforms induced by interleukin (IL)-4, a Th2 cytokine shown by others to increase arginase activity in macrophages, and serum. Results indicate IL-4, in concert with serum, increases AI, but not AII, mRNA in cultured murine macrophages. Moreover, they show serum to induce both arginase isoforms and to be required for maximal AI induction by IL-4. Together with the enhanced expression of AI, IL-4 induced the expression of the cationic amino acid transporter MCAT-2 and increased L-arginine transport into the cells. Present results confirm, then, specificity in the ability of macrophage arginase isoforms to be induced by different stimuli. Moreover, they suggest that a decrease in intracellular L-arginine concentration resulting from its consumption by arginase may be repaired by concurrent increases in L-arginine influx into the cell.

Amino Acid Transport Systems, Basic↗
PubMed1999

Vestigial respiratory burst activity in wound macrophages.

Macrophages from experimental wounds in rats were tested for their capacity to generate reactive oxygen intermediates. Measurements of superoxide and H2O2 release, O-2-dependent lucigenin chemiluminescence, oxygen consumption, hexose monophosphate shunt flux, and NADPH oxidase activity in cell lysates indicated, at best, the presence of a vestigial respiratory burst response in these cells. The inability of wound cells to release O-2 was not rekindled by priming with endotoxin or interferon-gamma in vivo or in vitro. NADPH oxidase activity in a cell-free system demonstrated that wound macrophage membranes, but not their cytosols, were capable of sustaining maximal rates of O-2 production when mixed with their corresponding counterparts from human neutrophils. Immune detection experiments showed wound macrophages to be particularly deficient in the cytosolic component of the NADPH oxidase p47-phox. Addition of recombinant p47-phox to the human neutrophil-cell membrane/wound macrophage cytosol cell-free oxidase assay, however, failed to support O-2 production. Present findings indicate an unexpected deficit of wound macrophages in their capacity to generate reactive oxygen intermediates.

Animals↗
PubMed1999

Trauma-hemorrhage delays wound healing potentially by increasing pro-inflammatory cytokines at the wound site.

BACKGROUND: Studies indicate impaired wound healing after trauma. The underlying mechanism remains unknown. METHODS: Mice were subjected to midline laparotomy, and polyvinyl alcohol sponges were implanted subcutaneously before hemorrhage (35 +/- 5 mmHg for 90 minutes, resuscitated) or sham operation. Wound exudate cells from the sponges were harvested on the first, third, and fifth postoperative day and cultured for 24 hours. Interleukin (IL)-1 beta, IL-6, monocyte chemotactic protein-1 (MCP-1), macrophage inflammatory protein-2 (MIP-2), and transforming growth factor (TGF)-beta were determined in the supernatants. IL-1 beta and IL-6 were measured in the wound fluid. RESULTS: Hemorrhage decreased collagen deposition in the wound. TGF-beta release was significantly decreased on the first and third postoperative days after hemorrhage, whereas IL-1 beta and IL-6 release was increased at 3 and 5 days after hemorrhage. Similarly, IL-1 beta and IL-6 in the wound fluid were significantly increased at 3 days after hemorrhage. CONCLUSIONS: Because increased levels of pro-inflammatory cytokines and decreased amounts of TGF-beta have been reported to impair the process of wound healing, the increased release of IL-1 beta and IL-6 and the decreased release of TGF-beta after hemorrhage might contribute to the decreased collagen production in those animals. Thus, attempts to locally change the ratio of those cytokines in trauma victims might be useful for improving wound healing in those patients.

Animals↗
PubMed1998

Role of nitric oxide in mediation of macrophage cytotoxicity and apoptosis.

Macrophages can recognize and eliminate tumor cells. To this effect, these cells use a variety of cytotoxic effectors. Recent work has paid particular attention to nitric oxide (NO) and its metabolic by-products in mediating macrophage tumor cytotoxicity. Moreover, work from this and other laboratories have indicated that macrophage-dependent, NO mediated tumor cell death meets the morphologic and molecular criteria that define apoptotic cell death. This review will initially discuss the characteristics of macrophage tumor cytotoxicity and the potential mechanisms by which NO can induce apoptosis in tumor cells. In addition, observations of spontaneous and acquired resistance to NO will be analyzed. Lastly, the relevance of results obtained using animal cells to the biology of the human macrophage will be considered.

Animals↗
PubMed1998

Distinct arginase isoforms expressed in primary and transformed macrophages: regulation by oxygen tension.

Experiments were performed to identify arginase isoforms expressed in primary and transformed rodent macrophages and to determine the molecular mechanisms for the previously observed increase in arginase activity in macrophages cultured in hypoxia or anoxia. Results demonstrate the following: 1) mRNA and protein for hepatic-type AI arginase are expressed in primary cultures of rat and mouse peritoneal macrophages and are enhanced seven- and nine-fold, respectively, by lipopolysaccharide (LPS). 2) mRNA for extrahepatic-type AII arginase is constitutively expressed in mouse, but not rat, peritoneal macrophages and is detected in RAW264.7 cells after LPS treatment; neither J774A.1 nor P388D1 cells contain arginase mRNA. 3) AI arginase mRNA, arginase activity in cell lysates, and L-arginine flux through arginase in intact cells are all increased in rat wound-derived and mouse peritoneal macrophages by hypoxic or anoxic culture; AII arginase mRNA is, in contrast, suppressed > 50% by O2 deprivation. 4) Expression of the L-arginine transporter mCAT-2 is increased greater than twofold by reduced O2 culture. These results demonstrate substantial variability in arginase isoform expression among primary and transformed rodent macrophages. They also identify AI and AII arginase and the mCAT-2 L-arginine transporter as O2-regulated genes.

Amino Acid Transport Systems, Basic↗
PubMed1996

B cell lymphoma-2 transfected P815 cells resist reactive nitrogen intermediate-mediated macrophage-dependent cytotoxicity.

Activated murine peritoneal macrophage cytotoxicity against P815 tumor cells has been shown to be mediated by the reactive nitrogen intermediates (RNI) produced by macrophages from L-arginine through nitric oxide (NO) synthase. Previous results from this laboratory indicated that NO-dependent killing of P815 fulfilled the criteria for apoptotic death. Work by others, in turn, demonstrated that the product of the bcl-2 gene confers protection against various inducers of apoptosis, including reactive oxygen intermediates. Experiments were performed to determine whether Bcl-2 could equally protect sensitive cells from RNI-dependent apoptosis within the context of a relevant biologic system such as the delivery of such RNI by activated macrophages. Results demonstrated that transfection of P815 cells with the human bcl-2 gene confers immunity from RNI-dependent, macrophage-mediated cytotoxicity. In contrast with wild-type or mock-transfected P815 cells, which do not contain detectable Bcl-2, bcl-2-transfected cells showed minimal DNA fragmentation and cell membrane failure when cocultured with activated macrophages. Additional findings indicate that Bcl-2 affords the transfected cells almost complete resistance to the DNA-fragmenting effects of chemically generated NO or H202 and partial protection from their cytolytic effects. These findings are consistent with the hypothesis that tumor cells expressing bcl-2 may escape destruction by macrophage-dependent immune surveillance mechanisms.

Animals↗
PubMed1996

Interleukin-6 production by rat hepatocellular carcinoma cells is associated with metastatic potential but not with tumorigenicity.

BACKGROUND: The phenotypic characteristics that allow some tumor cells to metastasize have not been fully identified. The production and/or response of tumor cells to various growth factors have been shown to distinguish cells of differing metastatic potentials. OBJECTIVES: To determine (1) whether rat hepatocellular carcinoma cell lines produce interleukin-6 (IL-6) and (2) whether production of IL-6 correlates with either metastatic potential or tumorigenicity. METHODS: The clonal cell lines 1682.C.2.9.L0 (poorly metastatic) and 1682.C.2.9.L10 (highly metastatic) were selected from a parental hepatocellular carcinoma induced in ACI rats by feeding an ethionine-containing diet and adapted to growth in vitro. RESULTS: Both cell lines resulted in primary tumors with equal frequency and developed a 40-mm nodule in a similar period time, when an inoculum of 5 X 10(6) cells was injected subcutaneously; however, only L10 cells metastasized to the lung. These cell lines did not demonstrate differential expression of several antigens noted to correlate with metastatic potential, including CD44 variant glycoprotein, p53, transferrin receptor, and E-cadherin. In contrast, L0 cells produced less than 10 U of IL-6 per milliliter in culture (as determined by bioassay using 7TD1 cells), whereas L10 cells released more than 95 U of this cytokine per milliliter under identical culture conditions (P<.01, Student's t test). In addition, serum concentrations of IL-6 were elevated in animals bearing L10-induced primary tumors but not in those with L0-induced tumors of comparable mass. Exogenous addition of IL-6 to both tumor cell lines had no effect on the rate of growth in vitro, supporting the similar the tumorigenic potentials observed in vivo. CONCLUSION: Excess IL-6 production appears to identify cells with metastatic potential and does not appear to be essential to the establishment of a primary tumor.

Animals↗
PubMed1996

NO is not sufficient to explain maximal cytotoxicity of tumoricidal macrophages against an NO-sensitive cell line.

Nitric oxide (NO) is a macrophage cytotoxic effector. Results presented here, however, demonstrate that NO does not fully explain macrophage cytotoxicity against NO-sensitive cells because (1) inhibition of NO production by activated macrophages reduces, not eliminates, cytotoxicity; (2) NO produced chemically in amounts equimolar to those released from macrophages fails to lyse P815 cells; and (3) macrophages isolated from wounds 10 days after injury generate NO just as tumoricidal activated macrophages but are not tumor cytotoxic. The noncytotoxic nature of these wound-derived macrophages is not explained by the release of inactive forms of NO, because they suppress lymphocyte proliferation in an NO-dependent manner, nor by the production of cytoprotective molecules, because their addition to activated macrophage-tumor cell cocultures does not quench cytotoxicity. Interestingly, cytotoxicity can be aroused in day 10 wound-derived macrophages by culture with lipopolysaccharide, and macrophages harvested earlier in the development of the wound are cytotoxic. By generating NO but not killing an NO-sensitive cell, day 10 wound-derived macrophages demonstrate that NO production is not sufficient to account for the killing of an NO-sensitive tumor by macrophages.

Animals↗
PubMed1995

Macrophage activation by culture in an anoxic environment.

The extracellular amino acid composition of experimental wounds in rats during peak macrophage infiltration bears the imprint of the elevated arginase activity present in wound fluid: L-arginine is found in this space in concentrations markedly lower, and L-ornithine in concentrations markedly higher, than those that are detectable in plasma. No evidence, in the form of L-citrulline or NO2- accumulation, can be found at this time for nitric oxide synthase (NOS) activity. Wound-derived macrophages, however, metabolize L-arginine through both arginase and NOS in culture. Given the requirements of NOS for O2 and the reduced O2 tension in wounds, experiments were performed to determine the role of O2 availability on the metabolism of L-arginine by wound-derived macrophages. Results demonstrated that, beyond inhibiting NOS, culture of wound-derived macrophages in an anoxic environment provided an activation signal, markedly increasing total L-arginine metabolism, arginase activity, NOS protein content, and the release of TNF-alpha and IL-6. Neither resident nor Corynebacterium parvum-elicited peritoneal macrophages responded to anoxic culture with increases in L-arginine utilization, arginase activity or, in the case of resident macrophages, in NOS protein content. The enhanced TNF-alpha and IL-6 release induced by anoxia in wound-derived macrophages was also found in resident peritoneal macrophages. Anoxia appears to act, then, as an inducer of activation-associated traits in macrophages obtained from different sites.

Animals↗
PubMed1995

On the expression of nitric oxide synthase by human macrophages. Why no NO?

The production of nitric oxide (NO) and its role in the anti-tumor and anti-microbial effects of rodent macrophages appears well established. In contrast, the circumstances required for its release from human monocytes/macrophages and its potential role in human pathology remain controversial. Evidence to be discussed suggests that NO is a redundant, autotoxic, immunosuppressive, and inefficient mediator of macrophage function. For these reasons, the expression of nitric oxide synthase as a rapid-response, high-output effector pathway may have been evolved out of the human monocyte/macrophage response repertoire or severely restricted in its expression. Hypothetical roles for a modest and circumscribed production of NO by human macrophages are proposed.

Arginine↗
PubMed1995

Impact of nitric oxide on macrophage glucose metabolism and glyceraldehyde-3-phosphate dehydrogenase activity.

Conflicting evidence has been presented regarding the role of nitric oxide (NO) in the regulation of cellular glucose metabolism. While it enhances glucose uptake and utilization through glycolysis and the hexose monophosphate shunt in macrophages and other cells, NO also inhibits glyceraldehyde-3-phosphate dehydrogenase, an enzyme catalyzing the metabolism of intermediates generated by both pathways. Indeed, it has been proposed that NO modulates glycolytic flux by suppressing glyceraldehyde-3-phosphate dehydrogenase activity. To establish the relative impact of these apparently incompatible actions, the effects of exogenous or endogenous NO on different aspects of glucose metabolism in macrophages were investigated. Cell activation increased NO production, maximal glyceraldehyde-3-phosphate dehydrogenase activity, and glucose metabolism through glycolysis and the hexose monophosphate shunt. NO generated endogenously or from S-nitroso-N-acetylpenicillamine (> 500 microM) reduced maximal glyceraldehyde-3-phosphate dehydrogenase activity in culture. The suppression of maximal glyceraldehyde-3-phosphate dehydrogenase coincided with decreased lactate accumulation only in concert with a marked loss of viable cells in the cultures. The maximal glyceraldehyde-3-phosphate dehydrogenase activity did not appear to be rate limiting for glucose metabolism when moderately inhibited by NO. A potential causal relationship between profound glyceraldehyde-3-phosphate dehydrogenase inhibition and cell death remains to be established.

Amino Acid Oxidoreductases↗
PubMed1995

Nitric oxide in inflammation and immunity.

Few discoveries have had as comprehensive an impact on the understanding of cellular physiology as the production of nitric oxide (NO.) from the terminal guanido amino group of L-arginine through nitric oxide synthases. The sheer volume of data presently coming forth on the physiology and pathophysiology of NO. ensures that any attempt at a comprehensive review will result in a simple snapshot of the event, soon to be outdated.

Amino Acid Oxidoreductases↗