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Biomedical subjects

T A Lane

Publications and source records attributed to T A Lane.

At least 55 records · Page 3Linked to original sources
PubMed1989

Modulation of endothelial cell expression of intercellular adhesion molecule 1 by protein kinase C activation.

Inflammatory stimuli enhance the adherence properties of human umbilical vein endothelial cells (HUVEC) for neutrophils (PMN). This is mediated in part by the up-regulation on HUVEC of Intercellular Adhesion Molecule 1 (ICAM 1). Phorbol esters, which activate protein kinase c (PKC), have also been reported to enhance the adherence properties of HUVEC for PMN. We investigated the effect of agents which activate PKC on the expression of ICAM 1 by HUVEC. Both phorbol myristate acetate (PMA) and Mezerein, a non-phorbol which also stimulates PKC, enhanced both the expression of ICAM 1 on HUVEC and the adherence of HUVEC for PMN. The PKC inhibitors staurosporine and H-7 prevented both PMA and Mezerein-induced stimulation of HUVEC expression of ICAM 1 and adherence for PMN. We conclude that activation of PKC in HUVEC is associated with increased expression of ICAM 1 on HUVEC. PKC-mediated up-regulation of ICAM 1 may be responsible, in part, for the promotion of endothelial cell adherence properties toward PMN.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed1989

Apparent coagulopathy caused by infusion of shed mediastinal blood and its prevention by washing of the infusate.

We found that reinfusion of shed mediastinal blood (SMB) after a cardiac operation was associated with laboratory evidence of disseminated intravascular coagulation. In view of this, we compared the effect of infusing washed or unwashed SMB on the coagulation profiles and blood use of two serial groups of patients undergoing cardiopulmonary bypass. We found that the results of testing for fibrin degradation products converted from negative to positive in 17 of 20 patients who received unwashed SMB versus 1 of 14 patients who received washed SMB (p less than 0.0001). Other coagulation studies did not reveal disseminated intravascular coagulation in either group, nor were there differences in blood use between the two groups. The unwashed SMB contained high titers of fibrin degradation products (mean reciprocal titer = 354 +/- 161) compared with washed SMB (mean reciprocal titer = 34 +/- 18) (p less than 0.01). Based on the volume of SMB infused, the amount of fibrin degradation products in unwashed SMB was sufficient to account for the positive fibrin degradation product assays after infusion in this group. We conclude that infusion of unwashed SMB may confuse the interpretation of tests for disseminated intravascular coagulation or fibrinolysis. As this could lead to unnecessary blood component use and is preventable by washing before infusion, we recommend that the routine infusion of unwashed SMB no longer be employed.

Blood Coagulation Tests↗
PubMed1989

The effect of storage on the metastatic potential of tumor cells collected in autologous blood. An animal model.

Malignancy in a potential autologous blood donor is considered by some as a relative contraindication for the collection of autologous blood. There is, however little experimental information regarding the safety of transfusion of autologous blood that may contain viable tumor cells. The purpose of this study was to determine if tumor cells seeded into autologous blood retain their metastatic potential and, if so, for how long. A well-established model of the pulmonary metastasis of B16/F10 (F10) melanoma in C57BL/6 mice was used. Equal numbers of F10 cells were seeded into CPDA-1 blood from the mice or into saline, and the number of lung tumors was evaluated 14 days after infusion of blood or saline. The CPDA-1 blood seeded with F10 cells was stored for up to 21 days in transfer packs at 4 to 6 degrees C, and the metastatic potential of F10 cells in the stored blood was ascertained as above. F10 cells seeded into autologous blood that was then transfused without storage gave rise to the same number of metastatic foci (404 +/- 32 metastases) as did those cells transfused in saline (374 +/- 38, p = 0.5). In contrast, the number of metastatic foci resulting from the transfusion of blood containing F10 cells decreased progressively after storage of the blood (7 days = 124 +/- 14 metastases; 14 days = 7 +/- 1; 21 days = 2 +/- 1; all p values less than 0.001 vs fresh blood). Also, the predilection of F10 cells to metastasize to the lung was unchanged by storage in blood.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

Increased adenosine concentration in blood from ischemic myocardium by AICA riboside. Effects on flow, granulocytes, and injury.

Morbidity and mortality from acute coronary artery occlusion may be reduced if local myocardial adenosine concentration is augmented because 1) coronary collateral blood flow during ischemia increases with adenosine infusion, and 2) granulocytes that accumulate in the microcirculation during ischemia are, to a large extent, inhibited by adenosine from generating superoxide anion free radicals, from adhering to vascular endothelium, and from damaging endothelial cells in culture. Using a cultured lymphoblast model system, we found that 5-amino-4-imidazole carboxamide (AICA) riboside enhanced adenosine accumulation during ATP catabolism. Therefore, AICA riboside pretreatment was used in canine myocardium to selectively increase adenosine concentration in the ischemic area during 1 hour of ischemia. At 5 minutes of ischemia, endocardial flow to ischemic myocardium in saline-treated and AICA riboside-treated dogs was 0.06 +/- 0.03 and 0.34 +/- 0.11 ml/min/g, respectively (p less than 0.01); flow to nonischemic myocardium was not affected. Ventricular tachycardia and premature ventricular depolarizations were significantly attenuated in the AICA riboside-treated dogs. Blood pressure and heart rate were not affected by AICA riboside. In venous blood from ischemic tissue, adenosine increased from undetectable levels (less than 0.01 microM) to 0.22 +/- 0.08 microM in saline and 1.79 +/- 0.06 microM in AICA riboside-treated dogs, respectively (p less than 0.001). Coronary vein inosine concentrations were greater in saline than in AICA riboside-treated dogs. In separate in vitro studies, AICA riboside did not alter the removal rate of adenosine from canine blood. Indium-labeled granulocyte accumulation was significantly less in ischemic myocardium in AICA riboside-treated compared with saline-treated dogs. In addition, adenosine, but not AICA riboside, inhibited in vitro canine granulocyte superoxide production. We conclude that AICA riboside given before myocardial ischemia augments adenosine concentration, decreases arrhythmias, decreases granulocyte accumulation, and improves collateral flow to ischemic myocardium. One of the beneficial mechanisms could be an increased production of adenosine rather than inosine from ATP catabolism that causes vasodilation and inhibition of granulocytes. We propose a new hypothesis regarding regulation of the inflammatory reaction to ischemia in the microcirculation. Adenosine, in addition to its vasodilator action, is an anti-injury autacoid that links ATP catabolism to inhibition of granulocyte adherence, microvascular obstruction, and superoxide anion formation.

Adenosine↗
PubMed1986

Increased infection mortality and decreased neutrophil migration due to a component of an artificial blood substitute.

We previously showed that an artificial blood substitute containing perfluorocarbons, Fluosol-DA, inhibited both neutrophil migration and adherence, due to its detergent component, Pluronic F-68. The purpose of the studies we report here was to determine if Fluosol or Pluronic might also reduce in vivo neutrophil migration and impair host resistance to bacterial infection. We studied in vivo PMN migration by injecting mice intraperitoneally (IP) with glycogen, followed by intravenous (IV) infusion of saline, Fluosol, or Pluronic. Peritoneal lavage after eight hours showed a significant decrease in the accumulation of PMN in lavage fluids of animals given either Fluosol or Pluronic (control--.19 +/- .03 X 10(6) PMN/mL, glycogen--1.35 +/- .14; glycogen/Fluosol--0.63 +/- .12; glycogen/Pluronic--0.69 +/- .07). We ascertained the effect of Fluosol and Pluronic on infection mortality by injecting mice IV with saline, Fluosol, or Pluronic, followed by a quantity of E coli (0.6 X 10(7] IP shown in preliminary studies to kill 20% to 50% of the mice in 24 hours. The 24-hour mortality was 14/45-saline, 24/32-Fluosol (chi 2 = 17.1; P less than .001) and 17/23 - Pluronic (chi = 11.2; P less than .001). Neither Fluosol nor Pluronic caused mortality without E coli. The increase in infection mortality occurred when Fluosol was given either two hours before, or simultaneously with E coli, but only with the simultaneous administration of bacteria and Pluronic. Pluronic did not alter reticuloendothelial system (RES) clearance function. These studies indicate that, in an animal model, Fluosol-DA, due to its detergent component Pluronic F-68, impaired neutrophil delivery to an inflammatory locus, and resulted in an increased rate of infection mortality. Since Pluronic did not result in RES blockade, but did impair the delivery of PMN to an inflammatory locus, our results suggest that the latter effect is responsible for the increase in infection mortality.

Animals↗
PubMed1984

Cultured human endothelial cells elaborate neutrophil chemoattractants.

The recruitment of circulating neutrophils to acutely injured lungs might be regulated by vascular endothelial cells. Conditioned media from confluent monolayers of endothelial cells derived from human umbilical veins were assayed for neutrophil chemotactic activity by the Boyden chamber technique. Among 20 confluent monolayers tested, 14 (70%) elicited chemotactic activity. The generation of chemotactic activity was time dependent. In four experiments, the chemotactic index at 6 hours of incubation was 3.7 +/- 0.4, at 24 hours was 5.0 +/- 0.5, and at approximately 48 hours was 6.6 +/- 0.6. Chemotactic activity was detectable in dilutions of 1:4 to 1:8. To characterize the factors in conditioned media responsible for enhanced neutrophil migration, pooled conditioned media from confluent endothelial cell monolayers eliciting maximal chemotactic activity (chemotactic index = 7.46 on pooled sample) were chromatographed on a Biogel A-0.5m column. Two column fractions corresponding to molecular weights of 35,000 and approximately 1500 daltons enhanced neutrophil migration. No migration-enhancing column effluents were observed from unconditioned medium. Both of the active column fractions from conditioned media were found to be chemotactic by checkerboard analysis. Activity in the 35,000-dalton peak was abolished by either treatment with Pronase or heat (56 degrees C X 30 minutes) but was not extracted into chloroform-methanol. Conversely, chemotactic activity in the 1500-dalton peak resisted heat and proteolysis but was extractable into chloroform-methanol. These data indicate that cultured human endothelial cells generate neutrophil chemoattractants, and that at least two chemoattractants, a 35,000-dalton protein and a 1500-dalton lipid, are generated. Our findings suggest that endothelial cells have the capacity to recruit neutrophils to vascular surfaces and may thereby initiate or modulate the inflammatory response.

Cells, Cultured↗
PubMed1984

A reassessment of the energy requirements for neutrophil migration: adenosine triphosphate depletion enhances chemotaxis.

In view of previous studies demonstrating a significant correlation between adenosine triphosphate (ATP) depletion and impairment of chemotaxis (CTX) during granulocyte (PMN) storage, we sought to quantitate the relationship between CTX and PMN energy metabolism. We incubated PMNs at 37 degrees C with 2-deoxyglucose (2-dg) in the presence of 5 mmol/L glucose. As expected, ATP inhibition by 2-dg was time-dependent (T 1/2, 18 minutes) and dose-dependent, with half-maximal inhibition of ATP (ID50) with 1.3 +/- .3 mmol/L 2-dg. Similar concentrations of 2-dg inhibited lactate generation, phagocytosis, superoxide anion generation, and degranulation. The random migration of PMNs was inhibited by somewhat higher concentrations of 2-dg (ID50, 12 mmol/L). In contrast, up to 40 mmol/L 2-dg did not inhibit CTX toward synthetic peptides or activated serum. In fact, 2-dg consistently increased the CTX of PMNs toward 10(-8) mol/L f-Met-Leu-Phe (fMLP), to a maximum of 450% of control CTX using 15 mmol/L 2-dg. Half-maximal stimulation (ED50) of CTX occurred at 6.3 +/- 1.0 mmol/L 2-dg. Although maximal CTX toward optimal concentrations of fMLP was consistently increased with 2-dg, the ED50 of CTX to fMLP was unchanged (ED50 with glucose, 2.0 +/- 0.6 nmol/L fMLP; ED50 with 2-dg 2.2 +/- 0.7 nmol/L fMLP), and 2-dg did not increase fMLP receptors. In the absence of glucose, 2-dg exerted similar effects on ATP and CTX, but at doses 30- to 50-fold lower than in the presence of glucose. Other glycolytic inhibitors (iodoacetamide and sodium fluoride) exerted similar effects. Additional studies indicated that CTX enhancement by 2-dg (a) required Mg++ but not Ca++, (b) occurred with PMNs from a patient with chronic granulomatous disease, (c) was unaltered in the presence of inhibitors of proteolysis, (d) was not due to generation of a soluble agent, (e) was not due to alterations in PMN adherence, and (f) was not due to inhibition of glycosylation. We conclude that the chemotaxis, but not the random migration, of PMNs is surprisingly resistant to inhibition of energy metabolism and depletion of ATP, since concentrations of 2-dg that decreased ATP and other cell functions by more than 50% not only did not inhibit, but actually stimulated, CTX. These studies also indicate that the previously reported correlation between ATP depletion and CTX impairment observed in stored PMNs are not causally related.

Adenosine Triphosphate↗
PubMed1984

Paralysis of phagocyte migration due to an artificial blood substitute.

We investigated the effect of a candidate artificial blood substitute, Fluosol-DA (FDA), on human neutrophil function in a serum-free medium. In a 50% (vol/vol) mixture with polymorphonuclear cells (PMN), FDA had no effect on PMN viability, phagocytosis, superoxide anion generation, degranulation, or bactericidal activity. In striking contrast, the random migration and chemotaxis of PMN to both f-Met-Leu-Phe (fMLP) and activated serum were inhibited by 98% +/- 2%, 95% +/- 2%, and 88% +/- 6%, respectively. Inhibition of chemotaxis by FDA required no preincubation, was dose-dependent (50% inhibition [ID50] with a 14% vol/vol mixture with FDA), and was fully reversible by washing PMN free of FDA after one hour but not after 18 hours of incubation (32% +/- 11% inhibition of chemotaxis). FDA itself was not chemotactic and did not impair either the chemotactic activity or binding of fMLP to PMN. FDA also inhibited PMN adhesion (ID50, 9 +/- 1 vol/vol%). The inhibitory component of FDA was found to be its detergent additive, Pluronic F-68, which inhibited random migration, chemotaxis, and adhesion with ID50s of 1.4, 2.4, and 2.9 mg/mL, respectively (equivalent to FDA concentrations of 5, 9, and 11 vol/vol%, respectively). All the other components of FDA were noninhibitory. Plasma samples from humans injected with 8 mL/kg FDA and plasma samples from rabbits injected with 16 mL/kg FDA or an equivalent concentration of Pluronic F-68, when mixed with autologous PMN, also severely inhibited PMN chemotaxis. We conclude that exposure of PMN to clinically relevant concentrations of FDA inhibits PMN migration, presumably due to inhibition of adhesion. The inhibitory effect is entirely due to the detergent, Pluronic F-68. Artificial blood substitutes containing Pluronic F-68 may compromise the ability of PMN to prevent or effectively control microbial infections.

Animals↗
PubMed1983

Myeloperoxidase-mediated modulation of chemotactic peptide binding to human neutrophils.

Methionine-containing chemotactic peptides, such as formyl-methionyl-leucyl-phenylalanine (FMLP), are inactivated via a neutrophil-derived, myeloperoxidase-mediated oxidation of the methionine residue. We report that extracellular inactivation of FMLP by myeloperoxidase modulates the apparent binding of methionine-containing chemotactic peptides to their surface receptors. Inhibitors of myeloperoxidase enhanced FMLP binding. At subsaturating concentrations of 3H-FMLP (20 nM), 1 mM cyanide (KCN) increased the binding of 3H-FMLP to human neutrophils (PMN) by 51% +/- 12%. Similar increases occurred with 0.1 mM azide and 10 mM aminotriazole (ATZ). KCN had little effect on maximal 3H-FMLP binding to PMN at saturation (control-17,040 +/- 910 receptors/PMN; KCN-16,820 +/- 1,940 receptors/PMN), but decreased the concentration of 3H-FMLP required to half-saturate the PMN receptors (control-39 +/- 3 nM; KCN-17 +/- 1 nM). ATZ gave similar results. The binding to PMN of the non-methionine-containing chemotactic peptide 125I-formyl-norleucyl-leucyl-phenylalanyl-norleucyl-tyrosyl-lysine (125I-FNLPNTL) was unaltered by KCN. Also, the binding of 3H-FMLP to myeloperoxidase-deficient PMN was unaltered by KCN. Both KCN and ATZ decreased the oxidation of FMLP by PMN. Finally, ATZ (but not KCN) enhanced the chemotactic migration of PMN in response to submaximal concentrations of FMLP. These studies show that intact PMN inactivate methionine-containing chemotactic peptides by a pathway that is sensitive to myeloperoxidase inhibitors and is absent in myeloperoxidase-deficient PMN. This action results in an apparent decrease in the affinity of the chemotactic peptide receptor for methionine-containing chemotactic peptides, which may modulate chemotatic events in inflammatory loci.

Amitrole↗
PubMed1982

The labeling of rabbit neutrophils with [111In]oxine.

We report here the successful labeling of rabbit peripheral blood neutrophils with [111In]oxine. We found that standard techniques for preparation of rabbit neutrophils, while acceptable for maintenance of in vitro function, rendered the neutrophils ineffective for in vivo use after labeling with 111In. Specifically, rabbit neutrophils were sensitive to the use of hypotonic shock for red cell elimination, centrifugation into a button during preparation, and the presence of oxine during chemotaxis in vitro. Using a carefully modified method of neutrophil preparation and labeling, we found that 111In-labeled rabbit neutrophils retained normal in vitro function, including chemotaxis. In addition, using our method, 34% +/- 5% of labeled neutrophils were recoverable in peripheral blood 5 min after intravenous injection. The half-life of circulating radio-labeled neutrophils was 5.6 +/- 2 h. Continuous external imaging of radio-labeled neutrophils after intravenous injection showed initial lung uptake, followed by rapid clearance of radioactivity in the lungs (50% clearance in 10.5 +/- 3.3 min.) Hepatic radioactivity was maximal by 30 min after injection and thereafter slowly declined. Finally, we found that 111In-labeled rabbit neutrophils migrated to sites of artificially induced inflammation. Our findings indicate that 111In-labeled rabbit neutrophils, if prepared under optimal conditions, should provide a useful tool for investigating the fate of neutrophils in experimental inflammatory conditions in this animal.

Animals↗
PubMed1982

Phagocytosis-induced chemotaxis receptor cycling in neutrophils is mediated by thiol oxidation.

We previously demonstrated that neutrophil (PMN) phagocytosis of opsonized zymosan (OPZ) caused oxygen-dependent inhibition of chemotactic peptide receptor (CPR) binding using the ligand 3H-formyl-methionyl-leucyl-phenylalanine (3H-FMLP). In the current studies we sought to determine the mechanism of CPR inhibition by OPZ. We found that 3 mM cysteine and 5 mM dithiothreitol (DTT) did not decrease PMN phagocytosis, but abolished CPR inhibition by OPZ. Furthermore, incubation of PMN with DTT after OPZ partially restored the suppressed CPR. PMN CPR saturation studies with 3H-FMLP on PMN incubated with or without DTT after phagocytosis indicated that DTT restored receptor numbers to 92% +/- 6% of prephagocytosis values and also improved CPR affinity for 3H-FMLP. In additional studies we found that the cell penetrating thiol reagents mercuric chloride (HgCl2), N-ethylmaleimide (NEM), and diamide, but not the nonpenetrating agents p-chloromercuriphenylsulfonic acid and p-chloromercuribenzoate, caused rapid, dose-dependent, DTT-inhibitable suppression of up to 85% CPR binding. CPR inhibition by HgCl2 and NEM was irreversible. PMN CPR saturation studies showed that NEM decreased total receptor numbers, not CPR affinity. The effect of NEM was not inhibited by receptor occupancy at 4 degree C or at 37 degree C. These studies indicate that: (1) intact thiol groups are a requirement for CPR ligand-binding; (2) the thiol groups are presumptively located on the interior side of, or within hydrophobic portions of, the plasma membrane and are not part of the 3H-FMLP binding site; (3) thiol oxidation-reduction induces reversible alteration in CPR binding; (4) phagocytosis-induced modulation of the CPR is due, in part, to thiol oxidation. These studies suggest that postphagocytic, thiol-mediated reduction in CPR binding may play a physiologic role in the inhibition of PMN chemotaxis at inflammatory sites. The state of CPR-associated thiols may be an important determinant of CPR binding under physiologic conditions other than phagocytosis.

Chemotaxis, Leukocyte↗
PubMed1981

Heterosexual relationships of psychiatric patients established during their treatment.

Thirteen cases of sexual partnership established during psychiatric treatment, where both partners suffered from a psychotic disorder, were studied. Poor selection of a mate, in terms of excessive differences of their ages, educational background and social status can be viewed as one facet of behaviour affected by mental illness. No patients derived support from such relationships, nor were stabilizing effects on the patients' psychopathology observed. It seems a fully justified conclusion that such relationships cannot be viewed as positive with respect to the stabilization of the patients' mental conditions and that they should be discouraged.

Adult↗
PubMed1979

Granulocyte concentrate function during preservation: effect of temperature.

Granulocyte concentrates collected from normal donors are necessarily stored for varying intervals up to the time of transfusion. However, information regarding the fate of collected cells and the optimal mode of storage in vitro in the interval between collection and transfusion is far from complete. We studied granulocyte function during preservation of granulocyte concentrates for up to 72 hr. The initial and most consistent alteration in granulocyte function during storage was failure of random migration and chemotaxis after 24 hr of storage (50% and 61% of normal, respectively). By 48 hr the respiratory burst was decreased by 42%, whereas at 48 hr phagocytic and bactericidal activities were nearly normal. Defects in migration and respiratory burst are not due to delayed activation of these functions but to absolute decreases in maximum rates of migration and oxygen consumption. Comparison of granulocyte concentrate storage at 6 degrees C versus room temperature indicated at 24 hr an improved (p greater than 0.02) but still abnormal (p greater than 0.02) chemotactic response with 24 degrees C storage and at 48 hr no difference in migration but a slight advantage in bacterial killing at 6 degrees C storage. These studies show that severe impairment of granulocyte function occurs within 24 hr of collection by centrifugal means; consequently, granulocyte concentrates should be transfused as soon as possible after collection.

Blood Bactericidal Activity↗
PubMed1979

Drug-induced agranulocytosis: in vitro evidence for immune suppression of granulopoiesis and a cross-reacting lymphocyte antibody.

Two patients with agranulocytosis associated with diphenylhydantoin (DPH) therapy and clinical data suggesting suppression of granulopoiesis were investigated using in vitro culture techniques for committed granulocyte/macrophage precursors. Addition of DPH to cultures containing the patients' sera resulted in significant suppression of colony growth. Extensive studies on the acute serum from one patient revealed the drug-dependent inhibitory activity to be nondialyzable, resistant to chloroform extraction, heat stable, active in the presence of heat-inactivated fetal bovine serum, active against autologous as well as allogeneic cells, and absent from convalescent sera. Drug-dependent bone marrow colony-suppressing activity was removed by absorption on an antiimmunoglobulin-Sepharose column but not by IgG-Sepharose. The serum show non-drug dependent suppression of oxygen consumption by normal polymorphonuclear leukocytes engaged in phagocytosis and also showed evidence of ability to opsonize these cells. When the serum was incubated with mitogen-stimulated lymphocytes, suppression of 3H-thymidine uptake by autologous but not allogeneic cells was noted. Similarly, the serum suppressed short-term 3H-thymidine uptake by autologous but not allogeneic bone marrow. Absorption of the patients' sera with allogeneic polymorphonuclear leukocytes, autologous polymorphonuclear leukocytes, or autologous lymphocytes removed the drug-dependent inhibitory activity, but absorption with allogeneic lymphocytes did not. These data are most consistent with the presence of a noncomplement dependent antibody capable of suppressing granulopoiesis, mediating peripheral destruction of polymorphonuclear leukocytes, and cross-reacting with a lymphocyte antigen of limited population distribution.

Agranulocytosis↗