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E J Goetzl

Publications and source records attributed to E J Goetzl.

At least 217 records · Page 12Linked to original sources

Clinical and immunologic effects of fractionated total lymphoid irradiation in refractory rheumatoid arthritis.

Ten patients with refractory rheumatoid arthritis were given 3000 rad of fractionated total lymphoid irradiation in an uncontrolled therapeutic trial. Total lymphoid irradiation was associated with objective evidence of considerable clinical improvement in eight patients and with reduced blood lymphocyte counts in all 10. On completion of irradiation, there was an abrogation of lymphocyte reactivity in vitro in the patients with clinical responses, but abnormal antibody activities characteristic of rheumatoid arthritis and normal components of humoral immunity were not suppressed. Partial recrudescence of arthritis occurred shortly after a year after the completion of irradiation and was paralleled by a restitution of lymphocyte concentrations and responsiveness to mitogens to levels similar to those observed before irradiation. These data provide further evidence of T-cell involvement in the pathogenesis of rheumatoid arthritis and demonstrate that total lymphoid irradiation can induce temporary relief, but they do not ascertain whether the natural history of this disease was altered.

Aged↗

Functional characterization of synthetic leukotriene B and its stereochemical isomers.

Leukotriene B (LTB), a potent lipid chemotactic factor for neutrophils, is 5S,12R-dihydroxy-6,14-cis,8,10-trans-eicosatetraenoic acid (Fig 1), based upon direct comparison of natural LTB with synthetic 5S,12R-dihydroxy-6,8,10,14-eicosatetraenoic acid (5,12-di-HETE) stereoisomers in three biological assays. Of the six synthetic stereoisomers evaluated, only the 5S,12R,6,14-cis,8,10-trans compound had chemotactic potency for human neutrophils in vitro that was comparable to that of natural LTB, with a concentration of 3 X 10(9-9) M eliciting a one-half maximum response. In contrast, the racemic mixture of 5R,12R- and 5S,12S-6,10-trans,8,14-cis, the racemic mixture of 5S,12R- and 5R,12S-6,10-trans,8,14-cis, the 5S,12R-6,8-trans,10,14-cis, the 5S,12R-6,8,10-trans,14-cis, and the 5S,12S-6,8,10-trans,14-cis stereoisomers required concentrations of 3 X 10(-7) to 1 X 10(-6) M to elicit comparable responses. Only natural LTB and its synthetic counterpart elicited a local neutrophil infiltration when injected into the skin of the rhesus monkey at 10 ng and 100 ng per site. Natural and synthetic LTB at a concentration of 3 X 10(-8) M each provoked an EC25 contractile response of guinea pig pulmonary parenchymal strips in vitro, whereas the other four tested stereoisomers of 5,12-di-HETE were inactive at this concentration. Structure-function analyses suggest that the neutrophil chemotactic activity depends critically upon the C-1 to C-12 domain, including the stereochemistry of the 6-,8-,and 10-olefinic bonds and the presence of both hydroxyl groups.

Animals↗

Isolation and partial characterization of membrane protein constituents of human neutrophil receptors for chemotactic formylmethionyl peptides.

Plasma membranes of human neutrophils were solubilized in buffer containing a nonionic detergent and applied to a formylmethionylleucylphenylalanine (fMet-Leu-Phe)-Sepharose column that was washed and eluted with the chemotactic peptide fMet-Leu-Phe. Analysis of the eluate by filtration on Bio-Gel P150 in sodium dodecyl sulfate (NaDodSO4) buffer and by NaDodSO4-polyacrylamide gel electrophoresis revealed three predominant membrane proteins of approximate molecular weight 94 000 (MP-1), 68 000 (MP-2), and 40 000 (MP-3), of which MP-2 accounted for 74--93% of the total protein. Purified MP-1 and MP-2 contained an above average content of hydrophobic amino acids, while MP-2 and MP-3 had an above average content of acid and/or amide amino acids and a below average content of basic amino acids. MP-2 and MP-3, but not MP-1, bound [3H]fMet-Leu-Phe in equilibrium dialysis chambers. Both MP-2 and MP-3 exhibited high-affinity sites with a valence of 0.2--0.3 and mean KA values of 9 x 10(8) and 2 x 10(7) M-1, respectively, and low-affinity sites with a valence of 0.3--0.5 and mean KA values of 3 x 10(7) and 2 x 10(6) M-1 (n = 3). The specificity of the binding of fMet-Leu-Phe was suggested by the failure of MP-2 and MP-3 to bind lipid chemotactic factors and to adhere to a Sepaharose column to which had been coupled chemotactic fragments of the fifth component of complement. A series of synthetic formylmethionyl peptides exhibited the same rank order of potency as inhibitors of the binding of [3H]fMet-Leu-Phe by MP-2 and as stimuli of neutrophil chemotaxis. Membrane proteins isolated by fMet-Leu-Phe-Sepharose affinity chromatography may represent constituents of specific human neutrophil receptors for chemotactic peptides.

Amino Acids↗

Molecular and cellular mechanisms of leukocyte chemotaxis.

The application of modern scientific methods to the study of leukocyte function has begun to reveal the molecular and cytostructural bases of the chemotactic responses of these cells. Leukocyte chemotaxis is initiated by the binding of chemoattractants to distinct plasma membrane receptors; this finding alters transmembrane potential and activates ionic fluxes. The subsequent sequence of metabolic processes leads to a rearrangement of cytoskeletal elements that is manifested by orientation and migration of the cells toward the source of the chemotactic gradient.

Animals↗

Novel structural determinants of the human neutrophil chemotactic activity of leukotriene B.

A specific 5(S),12(R)-dihydroxy-eicosa-6,8,10(trans/trans/cis), 14(cis)-tetraenoic acid, designated leukotriene B, is generated by the lipoxygenation and subsequent enzymatic hydration of arachidonic acid in a variety of leukocytes. Leukotriene B elicits a maximal human neutrophil chemotactic response in vitro which is similar in magnitude to those evoked by the chemotactic fragment of the fifth component of complement, C5a, synthetic formyl-methionyl peptides, and 5-hydroxy-eicosatetraenoic acid (5-HETE). The neutrophil chemotactic potency of purified leukotriene B, assessed by the 50% effective concentration of 6 x 10(-9) M, is equivalent to that of C5a, but is up to 100-fold greater than that of 5-HETE and of other natural di-HETE isomers. 5(S),12(R)-di-hydroxy-eicosa-6,8,10(all-trans),14(cis)-tetraenoic acid, which differs from leukotriene B only in having a trans-double bond in place of a cis-double bond in the triene portion of the molecule, and acetyl-leukotriene B are significantly less potent neutrophil chemotactic factors than leukotriene B, which indicates that both the conjugated double bonds and the free hydroxyl-group(s) are functionally critical determinants. The capacity of acetyl-leukotriene B to inhibit competitively and selectively the human neutrophil chemotactic response to equimolar concentrations of leukotriene B suggests the existence of a specific subset of receptors for this potent lipid mediator.

Acetylation↗

Tetrapeptides of the eosinophil chemotactic factor of anaphylaxis (ECF-A) enhance eosinophil Fc receptor.

Certain mast cell products, including the tetrapeptides Ala-Gly-Ser-Glu (Ala4) and Val-Gly-Ser-Glu (Val4) of the eosinophil chemotactic factor of anaphylaxis (ECF-A) and histamine, are preferentially chemotactic for eosinophils in vitro. Amino acid substitutions or modifications of the ECF-A tetrapeptides may substantially alter the chemotactic activity of human eosinophils. The cellular mechanism whereby ECF-A tetrapeptides enhance IgG-dependent killing of schistosomula by rat eosinophils is, however, unclear. We now report that the parent tetrapeptides and the substituted analogue Val-Pro-Ser-Glu (Pro3), but not histamine, increase the number of rat and human eosinophils that form rosettes with erythrocytes bearing IgG antibodies. Moreover, we find a correlation between the effect of these substances on the expression of rat eosinophil IgG Fc receptors and their capacity to increase the IgG-dependent cytotoxicity of rat eosinophils for Schistosoma mansoni schistosomula.

Animals↗

Cellular regulatory role of leukotriene B4: its effects on cation homeostasis in rabbit neutrophils.

We have found that exogenous leukotriene B4 modifies calcium homeostasis in rabbit neutrophils in a manner essentially analogous to that of the chemotactic peptide f-Met-Leu-Phe. Leukotriene B4 causes a rapid and dose-dependent increase in membrane permeability to calcium and a release of calcium from previously unexchangeable intracellular pool(s). The net result of these changes is to transiently elevate the intracellular level of exchangeable calcium. A stereoisomer of leukotriene B4 with greatly reduced secretory activity toward neutrophils (5S, 12S-di HETE) is essentially without effect on the rate of 45Ca uptake at concentrations equal to those that produce near maximal enhancement by leukotriene B4. Leukotriene B4, in addition to its effects on calcium metabolism, also increases the rate of 22Na influx into rabbit neutrophils. The relationships between the action of leukotriene B4 on calcium homeostasis and the neutrophil-directed activities of arachidonic acid and its lipoxygenase metabolites are discussed

Animals↗

Stimulus-specificity of the chemotactic deactivation of human neutrophils by lipoxygenase products of arachidonic acid.

Preincubation of human neutrophils with chemotactic concentrations of 5(S)-hydroxy-eicosatetraenoic acid (5-HETE) or 5(S), 12(R)-dihydroxy-6,14 cis-8,10 trans-eicosatetraenoic acid (leukotriene B4) induces a state of preferential chemotactic unresponsiveness to the homologous factor, termed deactivation, and less suppression of the responses to other chemotactic stimuli. The ratio of the concentrations required for maximal chemotactic deactivation of neutrophils to that which stimulates chemotaxis optimally is greater for 5-HETE and leukotriene B4 than for peptide and protein factors. In contrast to other chemotactic factors, 5-hydroperoxy-eicosatetraenoic acid (5-OOHETE) induces neutrophil chemotactic deactivation that is independent of the nature of the subsequent stimulus and is more slowly reversible after elimination of the fluid-phase deactivating factor. The unique characteristics of the chemotactic deactivation of human neutrophils by 5-OOHETE may be attributable in part to its endogenous metabolism to potent deactivating factors or to covalent derivatization of subcellular structures of the neutrophils by the highly reactive 5-OOHETE.

Arachidonic Acid↗

Stimulation of hexose uptake by human eosinophils with chemotactic factors.

The ability of several stimuli, all of which have been reported to stimulate eosinophil motility, to augment uptake or extracellular deoxyglucose (DOG), a glucose analogue, was studied. DOG uptake was stimulated in a concentration-dependent manner by the more potent chemotaxins--zymosan-activated serum, partially purified C5a. N-formyl-methionyl-leucyl-phenylalanine, and 5- and 11-hydroxyeicosatetraenoic acids. Less potent stimuli--the eosinophil chemotactic factor of anaphylaxis, histamine, and prostaglandin E2--did not stimulate DOG uptake. However, the correlation between the abilities of the agents to stimulate motility and DOG uptake was not completely uniform. Prostaglandin F2 alpha was a potent stimulant of DOG uptake yet is known to enhance only weakly chemokinesis and to be not chemotactic for eosinophils. The combined data from this and other studies indicate that these stimuli elicit specific and different sets of functional responses from eosinophils.

Arachidonic Acids↗

Mono- and dihydroxyeicosatetraenoic acids alter calcium homeostasis in rabbit neutrophils.

Products of the lipoxygenation of arachidonic acid that express neutrophil chemotactic activity were examined in vitro for effects on the uptake of 45Ca by rabbit peritoneal neutrophils. At optimally chemotactic concentrations, 5- and 11-hydroperoxyeicosatetraenoic acid, 11- and 12L-hydroxyeicosatetraenoic acid, and leukotriene B4 enhanced 45Ca uptake within 1 min by a mean of 212-694% of the values for control neutrophils incubated in buffer alone, as compared with 75% for 5(S)-hydroxyeicosatetraenoic acid and no effect for 15-hydroperoxyeicosatetraenoic acid and 15-hydroxyeicosatetraenoic acid. The approximate rank of potency of the factors stimulating 45Ca uptake was similar to that observed for chemotaxis. Leukotriene B4, in addition to stimulating the rate of 45Ca uptake into rabbit neutrophils, also displaced intracellular calcium. The net result of the leukotriene B4-induced changes in calcium homeostasis ws to elevate transiently the intracellular level of exchangeable calcium. That neutrophil lipoxygenase metabolites of endogenous arachidonic acid rapidly enhance the influx of 45Ca supports a possible role for such metabolites in general, and leukotriene B4 in particular, in the regulation of the intracellular levels of free calcium in the neutrophils and possibly in other hormonally sensitive cells in which this cation is a second messenger.

Animals↗

Total absence of eosinophils in a patient with an allergic disorder.

A 45-year-old woman with a 25-year history of episodic urticaria and rhinitis had no detectable eosinophils in blood or bone marrow; levels of other leukocytes were normal. No eosinophils were found in the nasal discharge or the exudate elicited in skin windows by ragweed extract, to which the patient exhibited an immediate-type hypersensitivity response. A complement-dependent IgG-related activity in the patient's serum cytotoxically degranulated human eosinophils in vitro without affecting neutrophils. Antieosinophil activity was confirmed by the ability of a single dose of the patient's serum to suppress significantly the eosinophil counts in monkeys for up to 12 hours. This is the first description of an isolated absence of eosinophils, a condition that may present with allergic manifestations.

Adult↗