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Biomedical subjects

R E Banks

Publications and source records attributed to R E Banks.

At least 37 records · Page 2Linked to original sources

Stimulation of inflammatory markers after blunt trauma.

BACKGROUND: Inflammatory mediators are released after trauma and may be related to the pathogenesis of sepsis. A prospective combined study of the pattern of release of an inflammatory mediator, interleukin (IL) 6, leucocyte activation (polymorphonuclear leucocyte (PMN) CD11b receptor expression and plasma elastase-alpha1 proteinase inhibitor complex (E-alpha1PI)) and soluble endothelial adhesion molecule expression (soluble E-selectin (sE-selectin) and soluble intracellular adhesion molecule 1 (sICAM-1)) was performed in patients suffering blunt trauma without adult respiratory distress syndrome (ARDS) or multiple organ failure syndrome (MOFS). METHODS: Thirty-one patients with a mean Injury Severity Score (ISS) of 14 (range 9-57) were studied. Venous blood samples were collected within 6 h of injury and then at 1, 3, 5 and 7 days. Leucocyte CD11b expression was quantified by flow cytometry. Serum IL-6, plasma E-alpha1PI, sE-selectin and sICAM-1 were measured by enzyme-linked immunosorbent assay. RESULTS: Serum IL-6, CD11b expression and E-alpha1PI levels were significantly raised above control values (P < 0.0001) on admission, slowly returning towards control values over the study period (median IL-6, 140 pg/ml versus undetectable; CD11b, 14.8 versus 6.4 mean channel fluorescence units; E-alpha1 PI, 208 versus 52 microg/l). The sICAM-1 level rose to a median of 539 ng/ml at 5 days (control 243 ng/ml). The median sE-selectin level also progressively increased to a maximum level of 80 ng/ml at 5 days (control 49 ng/ml). Eleven patients developed postoperative sepsis. Significant differences in CD11b expression were seen at days 3, 5 and 7 and in E-alpha1 PI at 6 h, 24 h and 3 days in patients who subsequently developed sepsis (P < 0.05). Severe injury (ISS 16 or greater) was associated with significantly greater responses in these measurements. CONCLUSION: These data show that markers of inflammation are specifically stimulated by trauma even when ARDS and MOFS do not occur. The CD11b receptor on PMNs may be useful in screening patients destined to develop post-traumatic sepsis.

Adult↗

Evidence for the existence of a novel pregnancy-associated soluble variant of the vascular endothelial growth factor receptor, Flt-1.

Angiogenesis is essential in physiological processes including ovulation, implantation and pregnancy. One of the most potent regulators is the cytokine vascular endothelial growth factor (VEGF). We provide evidence for a novel pregnancy-associated soluble variant of the VEGF receptor Flt-1. VEGF ranged from undetectable to 157.3 pg/ml (mean 49.9 pg/ml, SD 48.4 pg/ml) in plasma samples from normal volunteers (n = 10), but was undetectable in plasma from pregnant women (n = 12) and amniotic fluid (n = 10). Recoveries of spiked VEGF were poor in pregnancy-related samples, indicating the presence of VEGF-binding activity which was confirmed using biosensor and chromatographic techniques. Partial purification and protein sequencing indicated a novel soluble form of Flt-1 with a subunit size of 150 kDa. Normally present as a multimeric structure of approximately 400-550 kDa, complexes of 600-700 kDa were formed following binding of multiple VEGF molecules. Reverse transcriptase polymerase chain reaction of Flt-1 in placenta, amnion, chorion, human umbilical vein endothelial cells and cord blood samples produced bands of the predicted sizes but failed to identify any additional RNA species, and possible reasons for this are discussed. Soluble Flt-1 may be important in regulating the actions of VEGF in angiogenesis and trophoblast invasion and may have therapeutic implications in diseases with inappropriate angiogenesis such as proliferative retinopathies and cancer.

Amino Acid Sequence↗

Treatment of metastatic renal cell carcinoma with subcutaneous interleukin 2: evidence for non-renal clearance of cytokines.

The circulating cytokine concentrations following administration of subcutaneous recombinant interleukin 2 (IL-2) in combination with interferon alpha and 5-fluorouracil used to treat advanced renal cancer were studied. One patient was anephric and on dialysis, and seven had normal biochemical renal function, although five had undergone single nephrectomy. The pharmacokinetics of IL-2 and changes in IL-6 and tumour necrosis factor (TNF)-alpha were essentially similar in all patients including the anephric patient, irrespective of the periods of dialysis, although at some time points, IL-2 concentrations were slightly higher in the anephric patient than in the others. These results show that for subcutaneous administration of low-dose IL-2, renal clearance of IL-2 is not important. This contrasts with high-dose, intravenous IL-2 where blood concentrations are higher and renal clearance seems to occur, perhaps because of saturation of the non-renal mechanisms of clearance. The subcutaneous route is certainly preferred if IL-2 is used in anephric patients and in those with impaired renal function, and it may be generally preferred for most purposes.

Adult↗

Circulating soluble adhesion molecules E-cadherin, E-selectin, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in patients with gastric cancer.

The concentrations of the soluble adhesion molecules E-cadherin, E-selectin, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) were investigated in 45 patients with gastric cancer before treatment and their correlation with clinical, histological and routine laboratory parameters was examined. Data were collected on tumour stage at presentation, presence and sites of metastatic disease, tumour pathology, survival and results of routine laboratory tests. Serum concentrations of ICAM-1 and VCAM-1 were significantly elevated in the patients with gastric cancer in comparison with the group of healthy subjects (P < 0.00001 and P < 0.0001 respectively). Increased serum concentrations of VCAM-1 were associated with locally advanced and metastatic disease whereas ICAM-1 was significantly elevated both in local and in advanced/metastatic disease. Soluble E-cadherin and E-selectin concentrations did not show any significant elevation in gastric cancer patients. Concentrations of soluble adhesion molecules showed significant correlation with each other (except E-selectin and VCAM-1) and with alkaline phosphatase. Soluble ICAM-1 and VCAM-1 were significantly associated with an elevated total white cell count. Patients with elevated VCAM-1 had significantly poorer survival in comparison with patients with normal serum levels (P = 0.0361).

Adult↗

Production and characterization of monoclonal antibodies to human interleukin-12.

Interleukin-12 is a cytokine that plays a central role in mediating cell mediated immunity via enhancement of a TH1 cell response. IL-12, unusually for a cytokine, has a heterodimeric structure made up of 35 kDa and 40 kDa subunits. The aim of this study was to produce and characterize monoclonal antibodies to recombinant human IL-12. Twenty-two monoclonal antibodies to IL-12 were successfully produced and subunit specificity determined using recombinant human IL-12 and chimeric murine/human IL-12. All antibodies were shown to react with the p40 subunit by ELISA and immunoblotting with three of the MAbs being found to cross-react with murine IL-12. Using two individual bioassays for IL-12, seven of the MAbs were shown to neutralize biological activity of IL-12. Ten of the antibodies were found to be of use in immunocytochemistry, reacting with LPS-stimulated peripheral blood monocytes. The approaches and difficulties encountered in characterizing antibodies to a heterodimeric cytokine are discussed together with possible reasons for the failure to generate antibodies to the p35 subunit.

Animals↗

Effects of interleukin 6 administration on platelets and haemopoietic progenitor cells in peripheral blood.

Platelet numbers and circulating haemopoietic progenitor cells were examined in 12 patients with advanced malignancies who were receiving recombinant human interleukin-6 (rhIL-6) as part of an investigation of its thrombopoietic effects. Patients received recombinant glycosylated IL-6 by daily subcutaneous injection for 7 consecutive days in doses of 1, 3 or 10 micrograms/kg/day. Platelet numbers increased reaching a peak on days 12-15 with a mean on day 15 of 198.1% of pre-treatment values. This was accompanied by a significant fall in the mean platelet volume (mean decrease of 10.6%, P = 0.0044). No significant correlation was seen between the IL-6 dose and the change in platelet number. No significant differences were observed between pre- and post-treatment levels of circulating erythroid burst-forming units (E-BFU) and granulocyte macrophage colony-forming units (GM-CFU) but a small significant increase was seen in circulating primitive progenitor cells measured in a plastic-adherent (P delta) assay (P = 0.025). As positive controls, a group of patients treated with cyclophosphamide/G-CSF showed significant increases in GM-CFU (P = 0.018), E-BFU (P = 0.018) and P delta progenitors (P = 0.028). These data suggest that the thrombopoietic effects of IL-6 are mediated at a relatively late stage via effects on megakaryocyte differentiation, with a relatively small effect on circulating haemopoietic progenitors.

Adult↗

A phase II study of interferon-alpha, interleukin-2 and 5-fluorouracil in advanced renal carcinoma: clinical data and laboratory evidence of protease activation.

OBJECTIVE: To confirm the activity and evaluate the toxicity of the combination of subcutaneous interferon-alpha (IFN-alpha) and interleukin-2 (IL-2) with intravenous 5-fluorouracil (5-FU) in patients with advanced and recurrent renal carcinoma and of performance status 0-2. Additionally, to examine protease, complement and neutrophil activation as potential mediators of IL-2 toxicity. PATIENTS AND METHODS: Fifty-five patients were treated in an 8-week cycle with IFN-alpha (6 MU/m2 on day 1 in weeks 1 and 4 and thrice weekly in weeks 2-3, and 9 MU/m2 thrice weekly in weeks 5-8) IL-2 (20 MU/m2 on days 3-5 in weeks 1 and 4 and 5 MU/m2 thrice weekly in weeks 2-3) and 5-FU (750 mg/m2 on day 1 of weeks 5-8). Patients responding to the first cycle were eligible to continue with further cycles. Toxicity and effects on quality of life were assessed using World Health Organization criteria and the Rotterdam Symptom Checklist and Hospital Anxiety and Depression Scale. Serum levels of C3a, prekallikrein and elastase-alpha 1 proteinase inhibitor (elastase-alpha 1-antitrypsin) were assayed in a subset of patients before, during and after the administration of high-dose IL-2 in week 1. RESULTS: There were partial remissions in nine patients, with responses in 24% (95% CI 10-38%) of evaluable patients and 16% of all patients. Amongst 25 evaluable patients who had undergone nephrectomy, the response rate was 32% (95% CI 14-50%), whereas there was only one response amongst 22 patients who had not undergone nephrectomy. The median survival for patients with stable disease or partial remission exceeded 22 months. Outcome and survival were related to performance status, number of sites of metastases and nephrectomy. This group of patients was of relatively poor performance status and 18 patients (36%) failed to complete one 8-week treatment cycle. Cardiovascular and renal toxicities were less than those seen with intravenous IL-2 schedules but 44% of patients experienced at least one grade III toxicity and only 14% reported less than two grade II toxicities. Plasma levels of elastase-alpha 1 proteinase inhibitor exceeded the normal range in three of seven patients tested before treatment and increased in all seven patients after treatment with IL-2. The same three patients had raised levels of C3a before treatment and in all patients examined, C3a increased after treatment with IL-2. In contrast, plasma prekallikrein concentrations were below normal before treatment and decreased further afterwards. CONCLUSIONS: This study confirms the activity of this regimen in patients of good performance status, with limited sites of disease and in those who are fit for nephrectomy, but also showed that treatment was associated with considerable toxicity. The administration of IL-2 is associated with protease activation which may be a suitable target for pharmacological intervention in attempts to ameliorate toxicity.

Adult↗

Cytokines in combination with chemotherapy for advanced renal carcinoma--the importance of patient selection.

An outpatient regimen of interferon-alpha (IFN-alpha), interleukin-2 (IL-2) and 5-fluorouracil (5-FU) was previously reported to have significant activity (response rate 48.6%) in patients with advanced renal cell carcinoma (RCC). The patient group reported were generally of good performance status (PS), had undergone previous nephrectomy and would be considered of good prognosis with respect to response and survival after treatment with IL-2. The characteristics of patients with RCC referred to specialist units in the UK differ from that patient group in that many patients present with metastatic disease, are of poor PS and are considered unfit for nephrectomy. We tested the three drug regimen in a representative patient group of 55 patients who had: median PS of 1 (range 0-2); median time from diagnosis to treatment of 2.7 months (0.2-113); and median number of sites of disease 3 (1-5). 22/55 had not had prior nephrectomy and 31 were considered of poor risk, 15 moderate risk and only 9 of good risk. Treatment consisted of an 8 week cycle of IFN-alpha 6 MU/m2 day 1 weeks 1 and 4 and thrice weekly weeks 2-3 and 9 MU/m2 thrice weekly, weeks 5-8. IL-2 20 MU/m2 days 3-5, weeks 1 and 4 and 5 MU/m2 thrice weekly weeks 2-3. 5-FU 750 mg/m2 day 1 of weeks 5-8. There were no complete responses (CR), 9 (17%) partial responses (PR) and 13 patients (24%) had stable disease. Sixteen patients withdrew early from treatment and were not evaluable for response. Amongst 25 evaluable patients who had undergone nephrectomy the response rate was 32% (95% CI: 14-50%). Only 1 response was seen in patients who had not undergone nephrectomy. Survival was predicted by PS, nephrectomy, number of sites of metastasis and risk group. Most patients experienced significant toxicity of grade I/II but few grade III/IV toxicities were seen as compared to intravenous IL-2 regimens. These data are part of a large data set that has been submitted for publication in The British Journal of Urology. The regimen has been shown to have activity but this is seen predominantly in patients of good PS, with prior nephrectomy and limited sites of disease. Patients of poor risk are likely to experience significant toxicity without benefit and should be offered alternative palliative therapies.

Adult↗

Soluble E-cadherin concentrations in patients with systemic inflammatory response syndrome and multiorgan dysfunction syndrome.

We have assessed the role of the cell-cell adhesion molecule, E-cadherin, in the pathogenesis of multiorgan failure in 24 intensive care patients with sepsis and varying degrees of organ dysfunction, compared with 21 healthy subjects. Plasma soluble E-cadherin (sE-cadherin) was measured by enzyme immunoassay. The median concentration of sE-cadherin in normal subjects was 3.21 micrograms ml-1 compared with 6.00 micrograms ml-1 in patients with sepsis and organ dysfunction (P = 0.0019). There was no statistically significant difference in concentrations of sE-cadherin in survivors compared with non-survivors. Concentrations of sE-cadherin tended to increase with the severity of organ failure. We conclude that sE-cadherin is increased in inflammation and injury, and may be related to the degree of multiorgan failure after sepsis.

APACHE↗

Effect of cell density on the expression of adhesion molecules and modulation by cytokines.

Little is known about the regulation of integrin expression. Using flow cytometry, we have characterized the expression of integrin subunits and other adhesion molecules in bladder and colonic cell lines and studied their modulation by the cytokines tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma). We show that although TNF-alpha and IFN-gamma may modulate integrin expression, these effects are, in the case of some integrin subunits, secondary to cytokine-induced changes in cell density. Cell density-dependent changes in the expression of alpha 2-, alpha 3-, alpha 6-, beta 1-, and beta 4-integrin subunits were seen. IFN-gamma produced density-independent decreases in expression of alpha 2- and beta 1-integrins and increases in expression of intercellular adhesion molecule-1 (ICAM-1), alpha 3-, alpha 6-, and beta 4-integrins. TNF-alpha produced increases in beta 1-integrin and ICAM-1 expression which were also density-independent. The expression of some integrin subunits is clearly density-dependent and the alterations seen are dependent on the cell line studied. This study illustrates the importance of including appropriate density-related controls in all investigations examining adhesion molecule expression.

Carcinoma, Transitional Cell↗

The acute phase protein response in patients receiving subcutaneous IL-6.

IL-6, tumour necrosis factor-alpha (TNF-alpha) and IL-1 are thought to be the key mediators of the acute phase response although much of the evidence is based on in vitro studies. It is not clear to what extent each of the acute phase proteins are regulated in vivo by each of these cytokines. The aim of this study was to examine the effects of IL-6 treatment in eight patients with cancer on the concentrations of an extensive range of positive and negative acute phase proteins. It was part of a larger investigation to assess the value of IL-6 in the management of chemotherapy-induced thrombocytopenia. IL-6 was administered by a daily subcutaneous injection for 7 days at a dose level of 1, 3, or 10 micrograms/kg/day. Increases in the positive acute phase proteins, serum amyloid A, C-reactive protein, alpha 1-acid glycoprotein, alpha 1-antichymotrypsin, haptoglobin, alpha 1-antitrypsin, fibrinogen, complement component C3, and caeruloplasmin, were observed, with the greatest incremental changes and fastest responses being seen for C-reactive protein and serum amyloid A protein. The negative acute phase proteins transferrin, transthyretin and retinol binding protein all fell to a nadir within 48-96 h after the first IL-6 injection. Increases in complement component C4 were only found in two patients, which may be related to the increase in circulating TNF-alpha concentrations found only in these patients. This study has therefore shown that IL-6 is capable of causing changes in the majority of acute phase proteins in vivo. Although secondary induction of TNF-alpha was not observed in the majority of patients examined, it is still possible however that other cytokines involved in regulation of the acute phase response, such as IL-1, may have been induced and contributed to the overall response.

Acute-Phase Proteins↗

Adhesion molecules in inflammatory bowel disease.

The ability of leucocytes to adhere to endothelium is essential for leucocyte migration into inflammatory sites. Some of these adhesion molecules are released from the cell surface and can be detected in serum. The soluble adhesion molecules intercellular adhesion molecule 1 (ICAM-1), E selectin, and vascular cell adhesion molecule 1 (VCAM-1) were studied in the serum of patients with Crohn's disease, ulcerative colitis, and healthy controls. A second blood sample was taken from patients with active disease after one month of treatment and a third two months after remission was achieved. Tissue expression of the same adhesion molecules was studied by immunohistology. Circulating VCAM-1 concentrations were significantly higher in patients with active ulcerative colitis (n = 11, median = 165 U/ml) compared with patients with inactive ulcerative colitis (n = 10, median = 117 U/ml, p < 0.005), active Crohn's disease (n = 12, median = 124 U/ml, p < 0.02), and controls (n = 90, median = 50 U/ml, p < 0.0001). Within each disease group there were no significant differences in E selectin or ICAM-1 concentrations between the active and inactive states, however, patients with active Crohn's disease had significantly higher ICAM-1 concentrations (n = 12, median = 273 ng/ml) than controls (n = 28, median = 168, p < 0.003). VCAM-1 concentrations fell significantly from pretreatment values to remission in active ulcerative colitis (p < 0.01). In Crohn's disease there was a significant fall in ICAM-1 both during treatment (p < 0.01) and two months after remission (p < 0.02). Vascular expression of ICAM-1 occurred more often and was more intense in inflamed tissue sections from patients with ulcerative colitis and Crohn's disease than from controls. Vascular labelling with antibody to E selectin also occurred more often in patients with active inflammatory bowel disease. In conclusion, increased circulating concentrations of selected adhesion molecules are associated with inflammatory bowel disease. There is also evidence of local upregulation, particularly of ICAM-1. Differential expression of adhesion molecules in tissue may play a part in the initiation of leucocyte migration and local inflammation; the function of circulating adhesion molecules is unknown, but may play a physiological part in blocking adhesion.

Acute Disease↗

Soluble forms of the adhesion molecule E-cadherin in urine.

The adhesion molecule E-cadherin is essential for maintaining epithelial intercellular adhesion. Loss or reduced expression of E-cadherin has been related to invasive behaviour in a wide range of carcinomas. Using immunoblotting techniques, the existence of multiple soluble forms of E-cadherin was demonstrated in urine from healthy volunteers and patients with benign urinary tract disorders or bladder cancer. The existence of soluble forms of E-cadherin in the urine may reflect shedding from the urinary tract epithelium as part of the normal turnover of this molecule. The possibility that enhanced shedding may contribute to the loss of E-cadherin expression/function in malignancy is discussed.

Biomarkers, Tumor↗

Bone alkaline phosphatase in rheumatic diseases.

A double monoclonal immunoradiometric assay specific for bone alkaline phosphatase (BAP) was used to determine whether the raised total alkaline phosphatase (TAP) often found in patients with active rheumatoid arthritis (RA) and ankylosing spondylitis (AS) is derived from bone or liver. Fifty-eight patients with RA were compared to 14 with AS and 14 with non-inflammatory rheumatic diseases (NI). None had clinical liver disease and only one had a slightly elevated aspartate transaminase activity. Elevated BAP concentrations were found in seven patients (5 RA, 1 AS, 1 NI), only two of whom also had abnormal TAP. Abnormal TAP activities were found in only three patients (all RA). BAP did not correlate with disease activity in RA or AS. In contrast, TAP correlated with disease activity (assessed by plasma viscosity) in RA (P < 0.002) and gamma-glutamyl transferase (GGT) also correlated with plasma viscosity in RA (P < 0.01). Both TAP and BAP were significantly correlated with GGT in RA (P < 0.001 and P < 0.02, respectively). These findings are discussed, together with possible reasons for the conflicting nature of some of the observations.

Adult↗

The effect of warfarin on the attachment of bone to hydroxyapatite-coated and uncoated porous implants.

The attachment of bone to hydroxyapatite-coated and uncoated porous implants made of cobalt-chromium-molybdenum alloy was investigated with and without postoperative administration of warfarin sodium. The implants were placed transcortically in the femoral diaphysis of adult female goats and were evaluated after three, six, and twelve weeks in situ. Mechanical push-out testing and histological evaluation revealed that the attachment strength and the ingrowth of bone at the bone-implant interface increased with time in situ for both the hydroxyapatite-coated and the uncoated implants. The administration of warfarin significantly impaired both the attachment strength and the ingrowth of bone at twelve weeks. At twelve weeks, the attachment strength and bone ingrowth of the hydroxyapatite-coated implants in the animals that had received warfarin were statistically equal to those of the uncoated implants in the control animals.

Analysis of Variance↗