Biomedical subjects

G A Granger

Publications and source records attributed to G A Granger.

At least 37 records · Page 2Linked to original sources

PubMed1993

Release of soluble TNF/LT receptors from a human ovarian tumor cell line (PA-1) by stimulation with cytokines in vitro.

We have demonstrated the presence of the 55- and 75-kDa receptor for tumor necrosis factor (TNF) and lymphotoxin (LT) (TNF-R) in serum, and ascites from women with ovarian cancer. The present studies were initiated to begin to examine the possible cellular source of these receptors in women with ovarian cancer. Human ovarian tumor cells (PA-1) were cocultured for 24-48 hr with various levels of recombinant human cytokines (IL-1 beta, IL-4, IFN-gamma) and the supernatants were assayed by ELISA for the soluble forms of each receptor. PA-1 cells spontaneously release the 55-kDa TNF-R and low levels of the 75-kDa TNF-R. The release of both 55- and 75-kDa TNF-R was stimulated when PA-1 cells were cultured with IL-1 beta and IFN-gamma but unaffected by IL-4. The level of 55-kDa TNF-R was elevated slightly over spontaneous release but the level of 75-kDa TNF-R increased dramatically. IFN-gamma was the most potent stimulator of receptor release particularly of the 75-kDa TNF-R. IFN-gamma also induced increased expression of cell membrane TNF-R measured by binding of 125I-labeled TNF. Membrane TNF-Rs which were induced by IFN-gamma were the 75-kDa type, because TNF binding was blocked by anti-75-kDa TNF-R antibody. These data suggest that IFN-gamma selectively induced release and expression of 75-kDa TNF-Rs.

Cell Line↗

PubMed1993

The role of lymphotoxin in the IL-2-driven differentiation of human lymphokine-activated T-killer (T-LAK) cells in vitro.

Brief stimulation of human peripheral blood mononuclear cells with PHA and subsequent coculture with IL-2 results by 5 days in cultures of human lymphokine-activated killer (T-LAK) cells. While IL-2 drives the proliferation of these cells in vitro, their maturation into functional effector cells capable of cytokine secretion and cell cytokines depends on the presence of other cytokines. The role of LT in the differentiation and proliferation of human T-LAK cells in vitro was investigated. Higher levels of LT than TNF were secreted by T-LAK cells during the first 5 days of the primary culture, then secretion levels dropped sharply. Human T-LAK cells cultivated with anti-LT rabbit antisera showed a slight reduction in growth compared to normal rabbit serum controls. In contrast, phenotypic analysis by FACS showed a decrease in CD4+ and an increase in CD8+ populations of T-LAK cells in the treated cultures. Addition of LT from the beginning of the T-LAK cell culture resulted in an increase in CD4+ and a decrease in CD8+ cell populations at day 7. In addition, the cytolytic activity of non-MHC-restricted cytotoxicity and NK-like activity of anti-LT cultured T-LAK cells was also effected. These data indicated that LT may have a role in differentiation of IL-2 stimulated human T-LAK cells in vitro.

Antigens, CD↗

PubMed1992

Trafficking of syngeneic murine lymphokine activated killer T cells following intraperitoneal administration in normal and tumor bearing mice.

Nongenetically restricted T cells may be important host effector cells in women with ovarian cancer receiving intraperitoneal (ip) IL-2 therapy. We developed an in vitro technique to produce murine lymphokine-activated killer T cells. Murine splenocytes were cultured in the presence of 1000 U/ml IL-2 for 10 to 15 days. Phenotypical analysis showed 95% of total cells to express the pan T phenotype Thy 1.2 and no NK cell phenotypes by Day 7 in culture. These cells were labeled with 51Cr and their trafficking pattern after ip administration into normal and M5067 tumor bearing mice was examined. Various organs and tissues were collected at different timepoints and monitored for radioactivity. Within 4 hr., about 60% of the counts were associated with the bowel, peritoneum, and omentum of both normal and tumor bearing mice. About 15% of counts were associated with the blood, lung, kidney, spleen, and liver of both normal and tumor bearing mice.

Animals↗

PubMed1992

Immunotherapy of ovarian cancer. II. In vitro generation and characterization of lymphokine-activated killer T cells from the peripheral blood of recurrent ovarian cancer patients.

We examined the in vitro sensitivity of continuous ovarian cancer cells to lymphokine-activated killer T cells (T-LAK) alone or in combination with cytokines. Lymphocyte viability in T-LAK cultures generated from normal donors and ovarian cancer patients declined in the first 2 to 4 days; however, the remaining cells in these cultures maintained a constant rate of proliferation for long periods in vitro. These cells became 90-95% CD3+ TCR+ -alpha/beta T-cells after 7-10 days in culture. The T-LAK cells from normal donors and cancer patients expressed an equal ability to induce lysis of a panel of human target cells (NK-sensitive K562, NK-insensitive RAJI, and two human ovarian tumor lines, SKOV-3 and OVCAR-3), demonstrating that they are nongenetically restricted killers. Preincubation of either the effector or target cells with tumor necrosis factor or interferon-gamma or addition of these cytokines directly to cytolytic assays did not alter the degree of cell lysis in vitro. This is a method for generating large numbers of autologous, cytolytically active T-LAK cells from the blood of ovarian cancer patients that could be employed in adoptive intraperitoneal immunotherapy.

Cell Division↗

PubMed1992

The autocrine role of tumor necrosis factor in the proliferation and functional differentiation of human lymphokine-activated T killer cells (T-LAK) in vitro.

The autocrine role of tumor necrosis factor alpha (TNF) in the proliferation and functional differentiation of human lymphokine-activated T-killer cells (T-LAK) in vitro was investigated. Human peripheral blood lymphocytes initially stimulated with IL-2 and phytohemagglutinin-P (PHA) for 48 h will proliferate for long periods in vitro in the presence of IL-2. These T-LAK cells have been shown to be 95% CD3 positive. Employing ELISA techniques, greater than 500 pg/ml of TNF was found to be released in the supernatants of these cells during the first 5 days of culture. However, the levels dropped to 100-200 pg/ml by days 7-10. T-LAK cells grown from days 7 to 10 in the presence of IL-2 and rabbit anti-TNF were significantly growth inhibited (up to 23%). The cytolytic activity of T-LAK cells grown from days 0 to 7 in the presence of anti-TNF was also decreased (up to 75%). Phenotypic analysis of these anti-TNF treated T-LAK cells revealed a decrease in CD8 expression (up to 12%) and increase in CD4 expression (up to 27%) when compared with control cells. The data suggest that TNF has a regulatory role in the growth and functional differentiation of these human T-LAK cells.

CD4 Antigens↗

PubMed1992

Growth of the endometrial adenocarcinoma cell line AN3 CA is modulated by tumor necrosis factor and its receptor is up-regulated by estrogen in vitro.

We demonstrate that tumor necrosis factor (TNF) has a biphasic effect on the growth of the human endometrial adenocarcinoma cell line AN3 CA in vitro. Low levels (0.2-5 pg/ml) of TNF were moderately growth stimulatory (up to 20% enhancement), while levels over 100 pg were growth inhibitory (up to 45% inhibition). Northern blot analysis showed expression of the 75-kilodalton (kDa) TNF receptor mRNA, but no expression of the 55-kDa TNF receptor mRNA or TNF mRNA. The growth of these cells was not directly affected by physiological concentrations (10(-7)-10(-9) M) of 17 beta-estradiol (E2). However, [125I]TNF binding studies and Scatchard analysis showed that 18-h coculture with 10(-8) M E2 increased the number of TNF receptors expressed on these cells 3-fold. Quantitative mRNA analysis confirmed that 75-kDa TNF receptor mRNA expression increased within 4 h of incubation with E2. These observations suggest an interaction between the endocrine and the immune systems, with an important implication for the homeostasis of endometrial tissues.

Adenocarcinoma↗

PubMed1992

Blocking factors (soluble membrane receptors) for tumor necrosis factor and lymphotoxin detected in ascites and released in short-term cultures obtained from ascites and solid tumors in women with gynecologic malignancy.

Studies were conducted to identify and establish the cell and tissue source of blocking factors (BF), materials that inhibit the bioactivity of human TNF and LT in vitro. Ascites and samples of solid tumors were collected from women with various gynecologic malignancies. Supernatants were collected from cultures of tumor and ascites cells after 24, 48, and 72 h. Cell-free ascites (CFA) and culture supernatants were tested for their ability to block human recombinant TNF and LT-induced lysis of L929 cells in vitro. Levels of soluble forms of the 55- and 75-kDa TNF/LT receptors were measured by ELISA assay in the same samples. CFA and culture supernatants contained TNF/LT blocking factors and high levels of one or both soluble 55- and 75-kDa TNF/LT membrane receptors. Levels of BF bioactivity and receptors appeared rapidly, peaked at 24 h, and declined thereafter. Soluble TNF/LT receptors may be the active BF in these samples, and tumor tissues and ascitic cells may be a source of these receptors in the ascites fluid of these patients.

Ascites↗

PubMed1992

Transforming growth factor-beta 1 down-regulates expression of membrane-associated lymphotoxin and secretion of soluble lymphotoxin by human lymphokine-activated killer T cells in vitro.

Lymphokine-activated T killer lymphocytes (T-LAK) are important effector cells in various diseases of tissue destructive reactions. They require stimulation with various cytokines to proliferate and mature into function effector cells. We have examined the role of various endogenously and exogenously added cytokines, and tumor necrosis factor (TNF)/lymphotoxin (LT) receptors in this process in vitro. The present report is a continuation of these studies. We found that human T-LAK cells express membrane-associated LT (mLT) but not TNF, and secrete high amount of soluble LT (sLT) but low levels of TNF. When added to the initial cultures or immature T-LAK cells, transforming growth factor-beta 1 (TGF-beta 1) suppressed both mLT expression and sLT secretion by 30-40%. Coculture of mature T-LAK cells with TGF-beta 1 caused 35% down-regulation of both mLT expression and sLT secretion after 18 h of incubation. Kinetic experiments indicated reduction of LT mRNA synthesis could occur in as little as 1 h when cocultured with 5 ng/ml of TGF-beta 1. TGF-beta 1 also reduced mLT induced T-LAK cell cytolytic activity on L929 cells in vitro. It appears TGF-beta 1 can down-regulate LT mRNA syntheses, mLT expression, and sLT secretion of human T-LAK cells in vitro.

Cells, Cultured↗

PubMed1992

Studies of membrane-associated and soluble (secreted) lymphotoxin in human lymphokine-activated T-killer cells in vitro.

The expression, release, and cytolytic activity of membrane-associated lymphotoxin was examined in cultures of phytohemagglutinin-P (PHA-P) and interleukin 2 (IL-2)-stimulated human T-lymphokine-activated killer (T-LAK) cells in vitro. Lymphotoxin (LT/TNF-beta) was identified on the membrane of T-LAK cells using flow cytometry. The membrane form of LT (mLT) is detected not only on T-LAK cells but also on LT-secreting human B-cell lymphoid cell lines, RPMI 1788 and Raji, but not on U937 or K562 cells. Maximum expression of mLT on T-LAK cells and the secretion of LT into the supernatant depended on the concentration of IL-2. Expression of mLT on T-LAK cells was reduced by stimulation with PHA-P; however, supernatant LT levels greatly increased. Both expression of mLT and release of soluble LT was reduced after incubation of T-LAK cells with actinomycin D (ActD) or cycloheximide (CHx). Paraformaldehyde-fixed T-LAK cells caused cytolysis of WEHI 164 cells in vitro, which was blocked by anti-LT but not anti-TNF antibody. These data support the concept that mLT may be an intermediate form to secreted LT, and that the mLT form is cytolytically active.

Cell Line↗

PubMed1991

A 20 amino acid synthetic peptide of a region from the 55 kDa human TNF receptor inhibits cytolytic and binding activities of recombinant human tumour necrosis factor in vitro.

Tumour Necrosis Factor (TNF) and Lymphotoxin (LT) can exert a wide range of effects on cells and tissues and they are important effector molecules in cell mediated immunity. All these effects are induced subsequent to the binding of these cytokines to specific membrane receptors. Recently, two of these membrane receptors of 55 and 75 kDa, have been identified which share some amino acid (AA) homology in their N-terminal extracellular domains but differ in their intracellular domains. We synthesized two synthetic 20 AA peptides from hydrophilic regions of the N-terminal extracellular domains of the 55 kDa receptor; peptide A shares homology with both 55 and 75 kDa receptors, peptide B is unique. We found peptide B inhibits both the binding and cytolytic activity of recombinant human TNF when tested on murine L929 cells in vitro. Polyclonal antiserum generated against peptide B will block binding of 125I-labelled TNF to these cells in vitro. However, peptide A and antiserum prepared against peptide A are without effect in these same assay systems. These data suggest that the 20 AA sequences from AA 175 to 194 in the N-terminal extracellular domain of the 55 kDa TNF receptor are expressed on the cell surface and are involved in the binding of TNF.

Amino Acid Sequence↗

PubMed1991

Generation of stimulated, lymphokine activated T killer (T-LAK) cells from the peripheral blood of normal donors and adult patients with recurrent glioblastoma.

Peripheral blood mononuclear cells (PBM) from normal donors and patients with recurrent glioma were activated initially for 48-72 h with phytohemagglutinin-P (PHA) and recombinant human interleukin-2 (IL-2), and then proliferated in vitro for up to 5 months with IL-2. These cells are termed mitogen-stimulated lymphokine-activated T killer (T-LAK) cells. We measured patterns of T-LAK cell growth, in vitro cytolytic activity on a panel of continuous and primary tumor cells, and the phenotypes of the cells in these cultures. Lymphocyte viability declined dramatically over the first 3-5 days; and then the remaining cells in these cultures began to divide and maintained a constant 30-36 h doubling time for long periods in vitro. Phenotyping revealed that cells in the initial few days of culture were heterogeneous, but became almost totally CD3 T cells after 7-10 days in culture. The T-LAK cells from individual normal donors and cancer patients demonstrated a non-genetically restricted cytolytic ability against a panel of both continuous cell lines and primary autologous and allogeneic glioblastoma cells in vitro. This technique provides a method of generating large numbers of autologous cytolytic T cells with non-restricted anti-tumor activity that can be derived from peripheral blood mononuclear cells.

Adult↗

PubMed1991

Enhancement of lymphokine-activated T killer cell tumor necrosis factor receptor mRNA transcription, tumor necrosis factor receptor membrane expression, and tumor necrosis factor/lymphotoxin release by IL-1 beta, IL-4, and IL-6 in vitro.

Co-culture with IL-2 can induce human T lymphocytes to proliferate and become nongenetically restricted, lymphokine-activated killer (LAK) cells in vitro. Our studies were conducted with long term cultured, human T-LAK cells from peripheral blood, which are 95 to 99% CD3+. We found that proliferating 7 to 10-day human T-LAK cells express TNFR, by using a 125I-TNF binding assay. Additional treatment of these cells with the cytokines IL-1 beta, IL-4, or IL-6 rapidly up-regulated 55-kDa TNFR mRNA transcription and doubled TNFR membrane expression. Further studies revealed that these cytokines also increased the release of TNF and lymphotoxin (LT). Antibody neutralization studies indicated that IL-1 induces release of both TNF and LT; however, IL-4 and IL-6 induce primarily LT release. These results further support the concept that these cytokines are involved in the regulation of TNF/LT release, TNFR synthesis, and TNFR membrane expression. It is apparent that cytokines and their membrane receptors are involved in the autocrine/paracrine control of T cell proliferation, differentiation, and expression of functional activity after IL-2 stimulation in vitro.

Base Sequence↗

PubMed1991

The regulation of TNF receptor mRNA synthesis, membrane expression, and release by PMA- and LPS-stimulated human monocytic THP-1 cells in vitro.

The regulation of the 55-kDa TNF receptor (TNF-R) mRNA synthesis, membrane expression, and TNF binding factor (BF) release was examined in resting and activated human monocytic THP-1 and human promyelocytic leukemia HL-60 cells in vitro. Cells were activated with phorbol myristate acetate (PMA) and bacterial lipopolysaccharide (LPS). TNF alpha cytolytic activity in the supernatant of THP-1 cells stimulated by PMA began to appear at 4 hr, reached a peak at 8 hr, and declined by 12 hr. For THP-1 cells stimulated with LPS, the peak of TNF alpha activity appeared at 4 hr and then declined. TNF alpha-binding sites on the cell membrane were down-regulated within 1 hr after PMA and LPS treatment and then reappeared 12 hr later. Fifty-five-kilodalton TNF-R mRNA expression during this time period did not correlate with the level of membrane TNF-binding site expression. Additional studies indicated the presence of a 30-kDa TNF-BF in the supernatants which appeared after 24 hr. These data suggest that activated THP-1 and HL-60 cells are capable of releasing TNF-BF into the supernatant and this material may be involved in the control of secreted TNF alpha activities.

Base Sequence↗

PubMed1991

Identification of tumor necrosis factor and lymphotoxin blocking factor(s) in the ascites of patients with advanced and recurrent ovarian cancer.

Ascites obtained from human ovarian cancer patients contains material(s) that inhibit the cytolytic activity of tumor necrosis factor (TNF) and lymphotoxin (LT) in vitro. These inhibitor(s) are found in ascites from ovarian cancer patients and are detected in very low amounts in the ascites from patients with nonmalignant hepatic disease. These ascites TNF/LT blocking factors are heat sensitive and heterogeneous with respect to molecular weight. Kinetic studies indicate these factors inhibited cytolysis at the stage of TNF/LT interaction with membrane receptors on L929 cells. Because TNF and LT are key cytokines in host cell-mediated antitumor mechanisms, factor(s) that inhibit these cytokines could have a profound effect on the tumor host interaction and their presence in the ascitic fluid, should be considered before designing clinical trials that employ intraperitoneal administration of TNF or LT for immunotherapy of ovarian cancer.

Animals↗

PubMed1991

Rat mitogen-stimulated lymphokine-activated T killer cells: production and effects on C6 glioma cells in vitro and in vivo in the brain of Wistar rats.

An in vitro technique was developed to generate activated rat T cells, with antitumor activity. Splenic mononuclear cells (SMC) from outbred Wistar and inbred Wistar-Munich rats were stimulated with Concanavalin A and recombinant human interleukin-2 (rIL-2) in vitro for 48 h. After 2 days, the nonadherent cells began proliferating and were maintained in rIL-2 for up to 18 days in vitro. FACScan analysis revealed that SMC was a mixture of cell types; however, CD5+ T cells rapidly increased and became the predominant cell type after 5 days in culture. SMC induced cytolysis of YAC-1, but not C6 glioma cells in 4 h 51Cr release assays. In contrast, 5- and 9-day T cells lysed C6 glioma and YAC-1 cells. The C6 cells were admixed with cultured effector cells at various effector-to-target (E:T) ratios and were injected into the right cerebral hemisphere of Wistar and Wistar-Munich rats for a Winn assay. Histopathologic evaluations revealed that a) SMC had no effect; b) 2- and 5-day T cells, injected at E:T ratios greater than 5:1, caused significant reduction in tumor size; and c) 2- or 5-day T cells, at a 40:1 E:T ratio, resulted in little or no histologic evidence of tumor. Eighty-three percent of animals receiving C6 and 5-day mitogen-stimulated lymphokine activated killer cells at an E:T ratio of 40:1 were alive 120 days postinjection (p less than 0.05).

Animals↗

PubMed1990

Molecular cloning and expression of a receptor for human tumor necrosis factor.

A human tumor necrosis factor (TNF) binding protein from serum of cancer patients was purified to homogeneity and partially sequenced. Synthetic DNA probes based on amino acid sequence information were used to isolate cDNA clones encoding a receptor for TNF. The TNF receptor (TNF-R) is a 415 amino acid polypeptide with a single membrane-spanning region. The extracellular cysteine-rich domain of the TNF-R is homologous to the nerve growth factor receptor and the B cell activation protein Bp50. Human embryonic kidney cells transfected with a TNF-R expression vector specifically bind both 125I-labeled and biotinylated TNF-alpha. Unlabeled TNF-alpha and TNF-beta were equally effective at displacing the binding of labeled TNF-alpha to TNF-R expressing cells. Northern analysis indicates a single species of mRNA for the TNF-R in a variety of cell types. Therefore, the soluble TNF binding protein found in human serum is probably proteolytically derived from the TNF-R.

Amino Acid Sequence↗

PubMed1990

Mechanism of human lymphotoxin and tumor necrosis factor induced destruction of cells in vitro: phospholipase activation and deacylation of specific-membrane phospholipids.

The role of phospholipase (PLase) activation and lipid metabolism in lymphotoxin (LT)- and tumor necrosis factor (TNF)-mediated destruction of murine L929 cells was examined. At the levels of LT and TNF employed, cell destruction began at 4-6 h and was 99% complete by 30 h. Cell membrane phospholipids (PL), labelled in situ at the C2 position with 14C arachidonic acid, were analyzed by two-dimensional thin-layer chromatography and quantitated over a 30 h time course after LT or TNF treatment. The ratio of radiolabel incorporation relative to the actual amount of each PL present was determined by inorganic phosphate analysis. Radiolabelled arachidonic acid, eicosanoids, and neutral lipids were released into the medium prior to the onset of cell death (4-6 h) and continued to accumulate linearly throughout the destructive reaction. There was a quantitative relationship between the appearance of radiolabelled metabolites in the media and the loss of radiolabelled cellular PL. Cellular phosphatidylethanolamine was the primary PL deacylated by PLase action, showing a 75% reduction in radiolabel. The PLase inhibitors--quinacrine, hydrocortisone, dexamethasone, and indomethacin--were potent inhibitors of LT- and TNF-mediated cell destruction, suggesting that selective deacylation of specific membrane PL by PLase activation is an important step in the events that lead to LT- and TNF-mediated cellular destruction in vitro.

Animals↗

PubMed1990

Purification and characterization of an inhibitor (soluble tumor necrosis factor receptor) for tumor necrosis factor and lymphotoxin obtained from the serum ultrafiltrates of human cancer patients.

Serum ultrafiltrates (SUF) from human patients with different types of cancer contain a blocking factor (BF) that inhibits the cytolytic activity of human tumor necrosis factor alpha (TNF-alpha) in vitro. BF is a protein with a molecular mass of 28 kDa on reducing sodium dodecyl sulfate/polyacrylamide gel electrophoresis (SDS/PAGE). The active material was purified to homogeneity by a combination of affinity chromatography, PAGE, and high-pressure liquid chromatography. Amino acid sequence analysis revealed that BF is derived from the membrane TNF receptor. Purified BF blocks the lytic activity of recombinant human and mouse TNF-alpha and recombinant human lymphotoxin on murine L929 cells in vitro. However, BF inhibits the lytic activity of TNF-alpha more effectively than it does that of lymphotoxin. The BF also inhibits the necrotizing activity of recombinant human TNF-alpha when coinjected into established cutaneous Meth A tumors in BALB/c mice. The BF may have an important role in (i) the regulation and control of TNF-alpha and lymphotoxin activity in cancer patients, (ii) interaction between the tumor and the host antitumor mechanisms, and (iii) use of systemically administered TNF-alpha in clinical trials with human cancer patients.

Amino Acid Sequence↗