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Biomedical subjects

F Farzaneh

Publications and source records attributed to F Farzaneh.

At least 55 records · Page 3Linked to original sources
PubMed1997

Irradiated NC adenocarcinoma cells transduced with both B7.1 and interleukin-2 induce CD4+-mediated rejection of established tumors.

Previous studies have shown that expression of the immune co-stimulator B7.1 reduces the tumorigenicity of some, but not all, malignant cell lines. However, B7.1-expressing tumor cells are not very effective in inducing the rejection of established tumors. This may in part be due to induction of anergy in the potentially reactive T cells. Previous studies have shown that IL-2 can reverse the anergic state both in vitro and in vivo. Therefore, we have examined the effect of retrovirus-mediated delivery and expression of murine B7.1 and interleukin-2 on tumor formation and rejection of established MHC class I+/II- NC adenocarcinomas. Neither the expression of B7.1 nor IL-2 alone had a significant effect on NC tumorigenicity. In contrast, combined expression of B7.1 and IL-2 substantially decreased the tumorigenicity of these cells in the immunecompetent syngeneic hosts. T-cell depletion studies show this to be dependent primarily on the activation of CD4+ cells. Furthermore, distant subcutaneous injection of irradiated NC/IL-2/B7.1 can induce, much more effectively than NC/B7.1 or NC/IL-2, the rejection of small NC tumors, and prevent the recurrence of large surgically resected tumors. Together, these results suggest that tumor cells genetically modified to express B7.1 and IL-2 can induce the immune-mediated rejection of established class II- tumors by a mechanism involving CD4+ cells.

Adenocarcinoma↗
PubMed1997

Plasma levels and hepatic mRNA expression of transforming growth factor-beta1 in patients with fulminant hepatic failure.

BACKGROUND/AIMS: Transforming growth factor-beta1 is an important cytokine involved in cell growth and inflammation which has been shown to be inhibitory to hepatic DNA synthesis. The aim of this study was to investigate the plasma levels and hepatic mRNA expression of transforming growth factor-beta1 in patients with fulminant hepatic failure in whom liver regeneration may be impaired. METHODS: Plasma levels of transforming growth factor-beta1 and human hepatocyte growth factor were measured in 57 fulminant hepatic failure patients and 20 healthy volunteers by ELISA. Northern blot analysis of transforming growth factor-beta1 and H3 histone, a marker for liver proliferation, was performed in liver tissue of 14 fulminant hepatic failure patients. RESULTS: The plasma levels of total transforming growth factor-beta1 in fulminant hepatic failure patients on admission (median 38.8 ng/ml, range 8.4-108 ng/ml) were significantly higher than those in control subjects (23.0 ng/ml, 8.5-34.9 ng/ml, p<0.001). Significantly higher levels were observed in non-A, non-B hepatitis patients (57.9 ng/ml, 38.8-108 ng/ml, n=10, p<0.001) compared to patients with paracetamol overdose (37.1 ng/ml, 8.4-72.5 ng/ml, n=47). In contrast, the plasma levels of free transforming growth factor beta1 were greater in paracetamol overdose (623 pg/ml, 46.7-1241 pg/ml, n=21) than in non-A, non-B hepatitis (131 pg/ml, 77.2-254 pg/ml, n=9), with both being higher than control (72.3 pg/ml, 28.7-108, n=7, p<0.001). The plasma levels of human hepatocyte growth factor in patients with paracetamol overdose (7.04 ng/ml, 1.00-62.4 ng/ml) were significantly higher than those in patients with non-A, non-B hepatitis (4.48 ng/ml, 0.74-9.10 ng/ml, p<0.05). Northern blots showed increased mRNA expression of transforming growth factor-beta1 in paracetamol-overdose patients (n=8, p<0.05), but not in patients with non-A non-B hepatitis (n=6), compared to controls (n=4). CONCLUSIONS: The increased circulating plasma TGF-beta1 in FHF may be part of the tissue repair process in fulminant hepatic failure. In patients with non-A, non-B hepatitis, the increased total transforming growth factor-beta1 together with a less elevated hepatocyte growth factor could be related to impaired liver regeneration in this group.

Acetaminophen↗
PubMed1997

Enhanced immune costimulatory activity of primary acute myeloid leukaemia blasts after retrovirus-mediated gene transfer of B7.1.

Gene modification of malignant cells to express immune stimulators (cytokines and immune costimulators) has provided the basis for a novel form of immunotherapy. Using a MPSV-based retroviral vector with hygromycin resistance gene as a selectable marker, we have studied retrovirus-mediated gene transfer of an immune costimulator, B7.1, into primary human acute myeloid leukaemia (AML) cells and the subsequent induction of immune costimulatory function. AML blasts from 10 patients were transduced by co-culture for 48 h with or without haemopoietic growth factors (HGFs). In the absence of HGFs, transduction efficiency (TE), as judged by % B7.1 expressing cells, was low, varying from 0.3 to 8.2% (median 1.5%). Addition of HGFs increased the median TE 1.8-fold with stem cell factor alone and 2.6-fold with SCF, interleukin-3 and GM-CSF. Effects on cell cycling alone could not explain this difference, suggesting other factors such as virus binding and promoter activity, are also involved. CFU-AL assays indicated a higher transduction efficiency of clonogenic cells, which was not improved by growth factors. Limited duration of cell growth prevented significant expansion of transduced populations by culture in the presence of hygromycin. Although not increasing transduction efficiency, CD34 enrichment enhanced drug selection, by targeting cells with the greatest self-renewal capacity. Immunoselection of B7.1 expressing cells produced transduced populations with 30-60% expressing B7.1. In an allogeneic mixed leukaemic cell/T lymphocyte reaction (MLLR) transduced AML cells enriched by immunoselection were able to stimulate allogeneic T cells (CD4 and CD8 positive), which could be inhibited by a solubilised B7 receptor, CTLA4.Ig. Our results demonstrate that using a replication incompetent retroviral vector, it is possible to introduce the immune costimulator B7.1 into primary AML-blasts and by immunoselection, enrich the transduced cells, which may be used for subsequent administration as an autologous cellular vaccine.

B7-1 Antigen↗
PubMed1997

In vitro immune modulation by antibodies coupled to tumour cells.

Modification of autologous tumour cells to express the immune costimulator B7.1 is a potential strategy for immunotherapy of cancer. Previously, this has involved introduction of genetic material into cells, in vitro culture, and confirmation of the protein product on the cell surface. This is possible only if sufficient tumour is obtainable and efficiently modified in a short time. Whilst progress has been made on ex vivo tumour cell culture and transfection/infection procedures there are still tumour types for which the present means of gene transfer are not efficient enough. We describe a highly efficient in vitro procedure for the modification of over 99% of the cells in a population, allowing the expression of cell surface proteins with potential immune modulatory activities. This procedure, which can be completed in as little as 24 h with no upper limit on cell number, utilizes succinimide esters to label cell surface proteins with biotin covalently. Biotinylated cell membrane proteins then anchor an avidin bridge for immobilizing protein G'-biotin. This can serve to bind immunoglobulin (Ig) molecules via their Fc region such that the variable region of the antibody is freely and functionally available. In the present study the binding of a stimulatory mouse anti-human CD28 monoclonal antibody to the surface of tumour cells is used to show that the modified cells are capable of co-stimulating T cells in vitro. The simplicity of the method, and the use of common reagents, represents a further step towards a realistic, truly 'off-the-shelf', nongene immunotherapy protocol.

Animals↗
PubMed1997

Alcohol dehydrogenase: a target of humoral autoimmune response in liver disease.

BACKGROUND & AIMS: Liver-specific membrane lipoprotein (LSP) is a heterogeneous liver preparation that has been widely used to study autoreactivity in liver disease. The aim of this study was to identify autoantigens in LSP. METHODS: Guinea pig anti-LSP serum was used to screen a human liver complementary DNA (cDNA) library. Humoral immune responses to isolated potential autoantigens were investigated by immunoblotting in 91 pediatric patients with various liver diseases, 20 adult patients with alcoholic liver disease and 20 with autoimmune thyroid disease, 37 healthy children, and 20 healthy adults. RESULTS: A 1.6-kilobase cDNA insert isolated from the cDNA library was found to encode amino acids 61-374 of the human alcohol dehydrogenase (ADH)-gamma 1 subunit. Antibodies to this or other ADH subunits were found significantly more frequently in autoimmune liver diseases (19 of 39 patients; 49%), Wilson's disease (5 of 13 patients; 38%), and alcoholic liver disease (10 of 20 patients; 50%) than in normal controls (P < 0.0001, P < 0.005, and P < 0.05, respectively) and correlated with disease activity in autoimmune liver disease. CONCLUSIONS: ADH has been identified as a new antigenic component of the LSP using a xenogeneic antiserum to immunoprobe a human cDNA liver library and seems to be a target autoantigen in liver disease. This approach may be useful in identifying other potential autoantigens.

Adolescent↗
PubMed1996

Fetal hepatic alpha-fetoprotein mRNA expression in fetuses with trisomy 21 and 18 at 12-15 weeks gestation.

In this study we examined alpha-fetoprotein (AFP) mRNA expression in fetal liver at 12-15 weeks of gestation in trisomy 21 (n = 13), trisomy 18 (n = 5) and control fetuses (n = 24). No significant difference was found in the steady-state level of fetal liver AFP mRNA levels in either of the two trisomy groups studied. These findings suggest that the decrease in maternal serum AFP concentration found in trisomic pregnancies is unlikely to be the consequence of impaired transcription of the AFP gene by the fetal liver.

Blotting, Northern↗
PubMed1996

Cardiac gene expression of atrial natriuretic peptide and brain natriuretic peptide in trisomic fetuses.

OBJECTIVE: To investigate whether the increased nuchal translucency of trisomic fetuses is the consequence of heart failure by examining cardiac expression of atrial natriuretic peptide and brain natriuretic peptide genes. METHODS: Cardiac atrial natriuretic peptide and brain natriuretic peptide messenger RNA (mRNA) levels were measured in fetal hearts from 15 pregnancies affected by trisomy 21 or 18 at 12-16 weeks' gestation and from 30 normal controls at 10-20 weeks. RESULTS: In normal fetuses, mRNA levels of atrial natriuretic peptide decreased, but levels of brain natriuretic peptide did not change significantly with gestation. In trisomic fetuses, mRNA levels of both atrial natriuretic peptide and brain natriuretic peptide were significantly higher than in gestational age-matched normal controls. CONCLUSION: These data demonstrate that atrial natriuretic peptide and brain natriuretic peptide genes are transcribed prenatally, and the findings in trisomic fetuses suggest that the increased translucency of trisomic fetuses may be the consequence of heart failure.

Adult↗
PubMed1996

Gene expression of human pregnancy-associated plasma protein-A in placenta from trisomic pregnancies.

Placental pregnancy-associated plasma protein-A (PAPP-A) mRNA expression, placental PAPP-A protein concentration and maternal serum levels of PAPP-A were examined in pregnancies affected by trisomy 21 (n=8), trisomy 18 (n=7) and 15 normal controls at 12-15 weeks of gestation. The maternal serum concentration of PAPP-A in the trisomic group of pregnancies was significantly lower than in the normal controls. However there were no significant differences between the three groups in PAPP-A mRNA expression or PAPP-A protein concentration in the placental tissues. There was no significant association between the level of placental mRNA and either placental protein or maternal serum PAPP-A concentrations in the normal or trisomic pregnancies. There was however a significant association between placental protein and maternal serum PAPP-A concentrations in the normal and trisomy 21 pregnancies but not in those affected by trisomy 18. These findings suggest that the decrease in maternal serum PAPP-A in trisomic pregnancies is due to alternations in post-translational events such as protein stability, alterations in the release mechanism of the protein, impaired protein transport across the placenta or modified serum stability of PAPP-A.

Chromosomes, Human, Pair 18↗
PubMed1996

The effect of combined expression of interleukin 2 and interleukin 4 on the tumorigenicity and treatment of B16F10 melanoma.

The recent use of interleukin 2 (IL-2) and interleukin 4 (IL-4) single cytokine modified tumour cells in rodent models has demonstrated a potential use of these cytokines to produce autologous cancer cell vaccines. Here we compare the potential therapeutic benefit of transduction with IL-2 or IL-4 alone, and combined IL-2 + IL-4 in B16F10 cells, a murine malignant melanoma of poor immunogenicity. Transduction of B16F10 cells (MHC class I and II negative) to express either IL-2 or IL-4 alone delays the formation of tumours, IL-4 being more effective than IL-2. However, combined expression of IL-2 + IL-4 reduces tumorigenicity more than either cytokine alone. The eventual formation of tumours may result from loss of gene expression, and preliminary results suggest methylation of the retroviral long terminal repeat (LTR), rather than loss of the transduced DNA sequences. Histological examination of tumours expressing either IL-2 or IL-4 alone shows a non-specific inflammatory reaction with an increased tissue infiltrate of immune effectors (monocytes/macrophages, lymphocytes, granulocytes) localised around the tumour. In comparison, when cells expressing combined IL-2 + IL-4 were injected there were more granulocytes present, and perhaps more importantly, these were mainly localised within the tumour. The benefit of combined IL-2 + IL-4 expression results from a local rather than systemic effect as the growth of tumours from cells expressing IL-2 or IL-4 alone injected at distant sites was comparable with a single inoculation of cells expressing either cytokine alone. However, when cells expressing single cytokines IL-2 or IL-4 were mixed and injected at the same site, in comparison with the clonal population of cells expressing combined IL-2 + IL-4, tumour growth was characteristic of IL-4 alone rather than IL-2 + IL-4. Treatment of established tumours with a single injection of lethally irradiated tumour cells expressing IL-2 + IL-4 was sufficient to either reject tumours, or at least delay further tumour development. Furthermore, treatment stimulated an initial non-specific immune reaction that lead to a systemic immunity. Lethally irradiated wild-type cells were also successful in treating some established tumours, although this did not induce any systemic immunity. However, although successful in treatment studies, neither wild-type nor combined IL-2 + IL-4 expressing cells were able to vaccinate animals against a subsequent challenge with live wild-type tumour. These results indicate a potential therapeutic benefit with the use of combination IL-2 + IL-4 transduction of autologous cancer cells.

Animals↗
PubMed1996

Loss of heterozygosity on chromosome 5q in ovarian cancer is frequently accompanied by TP53 mutation and identifies a tumour suppressor gene locus at 5q13.1-21.

Forty-nine ovarian tumours were examined for loss of heterozygosity (LOH) on chromosome 5 using eight microsatellite markers spanning both arms, including one at the APC locus. LOH on 5q was a frequent event, detectable in 23 of 49 (47%) tumours, whereas 5p LOH was detected in only 1 of 22 tumours (5%). Six tumours showed partial LOH on 5q, enabling the candidate region to be localised to a 22 cM region proximal to APC, flanked by D5S424 and D5S644. An association was found between 5q LOH and TP53 mutation, with 18 of 23 (78%) tumours with LOH on 5q also harbouring a TP53 mutation. LOH on 5q was observed in 6 of 18 (33%) stage I tumours, suggesting that it may be an early event in the molecular pathogenesis of certain ovarian carcinomas.

Base Sequence↗
PubMed1996

Regulation of pancreatitis-associated protein (HIP/PAP) mRNA levels in mouse pancreas and small intestine.

1. In the present study we have examined the expression of pancreatitis-associated protein mRNA in mouse pancreas and small intestine and determined the effect of a number of factors on the steady-state level of the RNA. 2. The normally low level of pancreatitis-associated protein mRNA in pancreas increased severalfold after 6 h of hypoxia, reaching peak levels (approximately 10-fold greater than normal) after 24 h hypoxia. After 3 days' hypoxia pancreatitis-associated protein mRNA levels were again undetectable. 3. In the pancreas the level of pancreatitis-associated protein mRNA was also increased by alcohol and iron overload, but not by paracetamol. 4. In the small intestine expression of pancreatitis-associated protein mRNA was higher in normal ileum than in duodenum. In the ileum pancreatitis-associated protein mRNA levels were increased 7 to 15-fold after 6 h hypoxia, reaching peak levels by 24 h. Levels declined after 3 days' hypoxia, but remained higher than normal. 5. In the ileum long-term (4 weeks) dietary iron deficiency reduced pancreatitis-associated protein mRNA levels compared with control fed mice, whereas parenteral iron overload increased pancreatitis-associated protein mRNA levels. 6. The data presented suggest regulation of pancreatitis-associated protein gene expression by both oxygen tension and iron status.

Acetaminophen↗
PubMed1996

Placental mRNA expression of alpha and beta human chorionic gonadotrophin in early trisomy 18 pregnancies.

The placental expression of human chorionic gonadotrophin (HCG) I- and beta-subunits was investigated in eight pregnancies presenting with trisomy 18 and in 30 normal pregnancies at 11-15 weeks gestation. In the control group, the median densitometric scores of placental beta-HCG and I-HCG mRNA were 1.23 and 1.74 respectively. In the trisomy 18 group the median beta-HCG mRNA was significantly lower (0.16, Z = 2.29, P < 0.05) but alpha-HCG [0.60, Z = 1.75, P = 0.08) was not significantly different from normal. These findings suggest that in trisomy 18 the decrease in maternal serum concentration of HCG subunits results from an impairment in the transcription of the corresponding gene which affects the beta subunit to a greater extent than the I subunit.

Biomarkers↗
PubMed1996

Efficient retroviral infection of mammalian cells is blocked by inhibition of poly(ADP-ribose) polymerase activity.

Integration of proviral DNA into the host cell genome is a characteristic feature of the retroviral life cycle. This process involves coordinate DNA strand break formation and rejoining reactions. The full details of the integration process are not yet fully understood. However, the endonuclease and DNA strand-joining activities of the virus-encoded integrase protein (IN) are thought to act in concert with other, as-yet-unidentified, endogenous nuclear components which are involved in the DNA repair process. The nuclear enzyme poly(ADP-ribose) polymerase (PARP), which is dependent on DNA strand breaks for its activity, is involved in the efficient repair of DNA strand breaks, and maintenance of genomic integrity, in nucleated eukaryotic cells. In the present work, we examine the possible involvement of PARP in the retroviral life cycle and demonstrate that inhibition of PARP activity, by any one of three independent mechanisms, blocks the infection of mammalian cells by recombinant retroviral vectors. This requirement for PARP activity appears to be restricted to processes involved in the integration of provirus into the host cell DNA. PARP inhibition does not affect viral entry into the host cell, reverse transcription of the viral RNA genome, postintegration synthesis of viral gene products, synthesis of the viral RNA genome, or the generation of infective virions. Therefore, efficient retroviral infection of mammalian cells is blocked by inhibition or PARP activity.

3T3 Cells↗
PubMed1996

Expression of genes involved in iron metabolism in mouse intestine.

Intestinal nonheme iron levels and mRNA levels of genes implicated in iron metabolism were measured in mice with altered iron metabolism [chronic (4 wk) and acute (4 days) dietary iron deficiency; iron overload and hypoxia] to investigate their role in the process and regulation of intestinal iron absorption. Mucosal nonheme iron levels were decreased by both chronic and acute iron deficiency and increased by iron overload but were not affected by hypoxia. There was evidence of a gradient of mucosal nonheme iron along the small intestine (duodenum, jejunum > ileum). There were also regional differences in H-ferritin (duodenum > ileum) and transferrin receptor (ileum > duodenum) mRNA levels. Iron overload produced a decrease in transferrin receptor (TfR) mRNA in the duodenum, with ferritin mRNA levels unaffected in both the duodenum and ileum. Chronic iron deficiency induced a twofold increase in TfR mRNA levels in both the duodenum and ileum, whereas H- and L-ferritin mRNA levels did not change significantly. The ratio of H- to L-ferritin mRNA decreased significantly during exposure to hypoxia; however, individual ferritin and TfR mRNA levels were not significantly altered. Calreticulin (mobilferrin), cysteine-rich intestinal protein, and H(+)-adenosinetriphosphatase mRNA levels were virtually unchanged in all models. A comparison with previously published data on changes in iron absorption leads us to conclude that 1) iron absorption can be altered independently of effects on transcripts of genes for iron-related proteins, and 2) it is not essential for iron absorption to be coordinated with regulation of mucosal iron metabolism.

Animals↗
PubMed1996

Identification of 3 beta-hydroxysteroid dehydrogenase as a novel target of steroid cell autoantibodies: association of autoantibodies with endocrine autoimmune disease.

Autoantibodies directed against steroid hormone-producing cells (SCA) detectable by immunofluorescence are typically found in a small proportion of patients with premature ovarian failure (POF) as well as in other endocrine autoimmune diseases. The SCA pattern stains cells in the outer zones of the adrenal cortex, ovary, and testis. To identify the molecular target of SCA, an adrenal complementary DNA expression library was screened using SCA-positive serum, and the steroid enzyme 3 beta-hydroxysteroid dehydrogenase (3 beta HSD) was identified. Only 1 of 48 (2%) patients with idiopathic POF, not pre-selected for the presence of other autoimmune diseases, had SCA by immunofluorescence, whereas 10 of 48 (21%) had anti-3 beta HSD autoantibodies detectable by immunoblot using recombinant human enzyme compared with 6 of 115 (5%) control subjects (P = 0.002). Absorption of SCA-positive serum with recombinant human 3 beta HSD abolished the immunofluorescence pattern. We also examined the prevalence of anti-3 beta HSD autoantibodies in other endocrine autoimmune diseases. Two of 112 (2%) diabetic patients, but none of the thyroid or Addisonian patients, had SCA by immunofluorescence. Twenty-six (23%) diabetic subjects (P < 0.001 vs. controls), 3 of 18 thyroid patients (P > 0.05 vs. controls), and none of 4 Addisonian patients had anti-3 beta HSD autoantibodies. 3 beta HSD is the first steroid cell autoantigen defined at the molecular level to be associated with idiopathic POF occurring in the absence of other polyglandular diseases. Autoantibodies to 3 beta HSD in patients with other organ-specific autoimmune diseases indicate that the enzyme behaves as a typical target of polyendocrine autoimmunity. Anti-3 beta HSD autoantibodies in patients with POF may provide a marker of those subjects whose ovarian failure is autoimmune in origin and, as recent studies suggest, may be salvageable with glucocorticoid treatment.

3-Hydroxysteroid Dehydrogenases↗
PubMed1996

Comparison of IL-2- and IL-4-transfected B16-F10 cells with a novel oil-microemulsion adjuvant for B16-F10 whole cell tumour vaccine.

The use of whole cell tumour vaccines in the treatment of malignant melanoma has given mixed results. Cytokine-transfected tumour cells as vaccine have shown efficacy in animal models but need to be compared with other means of enhancing a systemic anti-tumour immune response. A new generation of immunological adjuvants claimed to be more effective than the conventional adjuvants is now available for assessment. We have investigated the action of an oil-microemulsion adjuvant formulation (IDEC antigen formulation (IDEC-AF)) in the B16-F10 murine melanoma model. After standardisation of the whole cell tumour vaccination protocol we showed that mice vaccinated with whole irradiated cells combined with IDEC-AF produced a significant inhibition of tumour growth, following a challenge with live tumour cells, when compared with mice vaccinated with whole cell vaccine alone. IDEC-AF was superior to two conventional adjuvants, namely alum and incomplete Freund's adjuvant and a more reliable response was achieved with the oil-microemulsion adjuvant compared with IL-2-transfected cells. In addition, the adjuvant was comparable in efficacy to IL-4-transfected B16-F10 cells. Given the practical difficulty in using cytokine-transfected tumour cells and the limited therapeutic range of some cytokines, a cheap and easy to deliver adjuvant formulation proved equally or more effective than some of the currently clinically used transfected cytokines.

Alum Compounds↗