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E J Goetzl

Publications and source records attributed to E J Goetzl.

At least 163 records · Page 9Linked to original sources

Neuropeptide regulation of the expression of immediate hypersensitivity.

Peptide mediators of sensory nerves that are released in tissues by noxious chemical and physical insults and by diverse biologic challenges rapidly elicit local and systemic responses similar to those of immediate hypersensitivity. The sensory neuropeptides have direct effects on the functions of smooth muscles, blood vessels, leukocytes, and epithelial glands and indirect effects through the actions of mediators released from mast cells stimulated by the peptides. Sensory neuropeptides exhibit cellular specificity, as exemplified by the greater potency of substance P in activating mucosal mast cells than connective tissue mast cells. The capacity of somatostatin to inhibit release of mediators from basophils challenged by IgE-dependent mechanisms, but not by basic peptides or ionophores, illustrates the biochemical specificity of the neuropeptides. The selective release of distinct sensory neuropeptides from different subsets of nerve endings, the specificity of neuropeptide recognition by mast cells, basophils, and other target cells, and the diversity of direct and indirect activities of the neuropeptides suggest that sensory nerves may initiate and modulate immediate hypersensitivity by unique mechanisms.

Basophils↗

Endogenous somatostatin-like peptides of rat basophilic leukemia cells.

The tetradecapeptide somatostatin (SOM 14) and a 28-amino acid biosynthetic precursor (SOM 28) are constituents of diverse neuroendocrine tissues that are released by noxious stimuli from a subset of sensory nerve endings, and substantially modify the functions of basophils and mast cells. SOM-like factors were detected initially in the fluid phase of suspensions of immunologically challenged rat basophilic leukemia cells (RBL), and were purified from ethanol/0.2 M acetic acid (3/1, v/v) extracts of replicate portions of 3 X 10(9) RBL. Sephadex G-25 columns resolved factors of over 10,000, 2000 to 4000, and 300 to 1200 daltons that are antigenically related to SOM 14, as assessed by a radioimmunoassay specific for SOM 14. Only the two larger factors were detected by a radioimmunoassay for SOM 28(1-14), which binds to prepro-SOM and SOM 28 but not SOM 14. Reverse-phase high performance liquid chromatography distinguished the two smaller SOM peptides of RBL from SOM 28 and SOM 14, respectively. Amino acid analyses showed major differences in composition between the 2000 to 4000 dalton SOM of RBL and SOM 28. Picomolar to nanomolar concentrations of both of the smaller SOM peptides of RBL inhibited the IgE-dependent release of histamine from basophils to the same extent as SOM 14. The finding of 3 to 5 ng of structurally unique SOM-like peptides per 10(8) RBL suggests that endogenous mechanisms analogous to those of specialized sensory neurons may regulate the expression of hypersensitivity.

Amino Acids↗

Transduction by leukotriene B4 receptors of increases in cytosolic calcium in human polymorphonuclear leukocytes.

The uptake of Quin-2 by human polymorphonuclear (PMN) leukocytes permitted accurate fluorimetric quantification of the cytosolic concentration of intracellular calcium [( Ca+2]in), without altering the expression of the two subsets of leukotriene B4 (LTB4) receptors, as assessed by the binding of [3H]LTB4. Chemotactic concentrations of LTB4 elicited a rapid increase in [Ca+2]in, which reached a peak within 0.6 to 1 min and then decayed back to baseline levels by 6 to 10 min. The maximal increase and the half-maximal increase in [Ca+2]in were achieved by LTB4 at mean concentrations of 5 X 10(-10) M and 2 X 10(-10) M, respectively, where the binding of LTB4 to high-affinity receptors predominates. A rank order of potency of LTB4 greater than 5(S),12(S)-6-trans-LTB4 greater than 12(S)-LTB4 was established for the elicitation of increases in [Ca+2]in, which reflects the binding of the isomers to low-affinity receptors. PMN leukocytes were preincubated with 10(-8) M LTB4 to induce chemotactic deactivation, which eliminates the expression of high-affinity receptors without altering the expression of the low-affinity receptors for LTB4. LTB4 elicited an increase in [Ca+2]in in the deactivated PMN leukocytes with an EC50 of 3 X 10(-8) M, which is similar to the Kd for LTB4 binding to the low-affinity receptors. Two lines of cultured human leukemic cells, IM-9 and HL-60, did not bind LTB4 specifically and did not show any change in [Ca+2]in upon the addition of 3 X 10(-8) M LTB4. The HL-60 human promyelocytic leukemia cell line was induced to differentiate in 1% dimethyl sulfoxide to leukocytes with more mature myelocytic characteristics. Differentiated HL-60 cells expressed an average of 54,000 low-affinity receptors for LTB4 per cell with an average dissociation constant of 7.3 X 10(-8) M and concurrently developed the capacity to respond to LTB4 with an increase in [Ca+2]in. The binding of LTB4 to either high-affinity or low-affinity receptors appears to be sufficient to initiate an increase in [Ca+2]in in human PMN leukocytes and differentiated HL-60 cells. The specificity of LTB4 receptors in transducing maximum increases in [Ca+2]in is determined by the subset of receptors that predominate as a result of the concentration of LTB4 and the state of the responding cells.

Aminoquinolines↗

The role of the polymorphonuclear leukocyte in hyperalgesia.

The results of recent studies of the mechanism of leukotriene B4-induced hyperalgesia suggest a dependence on polymorphonuclear leukocytes (PMNLs). In this study, we addressed the contribution of PMNLs to hyperalgesia evoked by the peptide chemotactic factors N-formyl-methionyl-leucyl-phenylalanine (fMLP) and the anaphylatoxin fragment of the fifth component of the complement pathway (C5a). Local injection of glycogen, which attracts but does not activate PMNLs, produced a marked shift to the left (toward lower concentrations) in the concentration dependence curve of fMLP-induced hyperalgesia. In addition, PMNL repletion by transfusion with syngeneic PMNLs reestablished fMLP-induced hyperalgesia in PMNL-depleted rats. Finally, supernatants from rat and human PMNLs, that had been stimulated with fMLP in vitro, produced hyperalgesia in PMNL-depleted rats. Preliminary characterization of the hyperalgesia-inducing activity released by stimulated PMNLs indicated that it is lipid in nature. The nonsteroidal anti-inflammatory indomethacin did not attenuate C5a and fMLP-induced hyperalgesia. Thus, the hyperalgesia produced by fMLP and C5a is similar to that produced by leukotriene B4 in that it is dependent on PMNLs and independent of the cyclo-oxygenation of arachidonic acid. Taken together, these data suggest that structurally diverse PMNL-chemotactic factors produce hyperalgesia by a novel mechanism, involving PMNL-derived factors.

Animals↗

Inhibition of human neutrophil receptor-mediated uptake of N-formyl-met-leu-phe by platelet factor 4 (59-70).

Human platelet factor 4 (PF4) and a substituent dodecapeptide designated PF4(59-70) elicited human neutrophil and monocyte chemotaxis with a similar concentration-dependence and maximal responses equal to that attained by chemotactic fragments of C5 (C5fr). At maximally chemotactic concentrations, PF4(59-70) stimulated the secretion by neutrophils of approximately 40% and 60% of the respective quantities of beta-glucuronidase and beta-glucosaminidase released by 10(-6) M N-formyl-methionyl-leucyl-phenylalanine (fMLP). In contrast to the deactivation of chemotaxis achieved by preincubation of neutrophils with other chemotactic factors, prior exposure to 10(-6)M PF4(59-70) for 2 min, or 20 min at 37 degrees, enhanced by 1.5- to 2-fold the chemotactic responses of neutrophils evoked by optimal concentrations of fMLP, C5fr, leukotriene B4, and PF4(59-70). Concentrations of PF4(59-70) which enhanced neutrophil chemotaxis inhibited the rate of receptor-mediated internalization of [3H]fMLP at 37 degrees and 18 degrees, but at 0 degrees failed to alter the binding affinity or the number of receptors for [3H]fMLP. Preincubation of neutrophils at 37 degrees with concentrations of PF4(59-70) which enhanced neutrophil chemotaxis also did not affect the subsequent binding of [3H]fMLP at 0 degrees. The inhibition by PF4(59-70) of the receptor-mediated internalization of [3H]fMLP was not mimicked by other positively charged compounds. The specific inhibition of receptor-mediated internalization of fMLP may explain the enhanced chemotactic responsiveness of neutrophils preincubated with PF4(59-70).

Acetylglucosaminidase↗

Structural diversity of the fibroblast-activating factors generated by human blood monocytes and U937 cells.

The incubation of purified human blood monocytes with phytohemagglutinin (PHA) and of cultured U937 human monocyte-like cells with phorbol myristate acetate (PMA) evoked the generation of fibroblast-activating activity, as assessed by stimulation of the uptake of [3H]thymidine by human dermal fibroblasts. Filtration of the supernates from monocytes and U937 cells on Sephadex G-75 resolved fibroblast-activating factors of m.w. 25,000 to 40,000, designated FAF-M and FAF-U937, respectively, from smaller factors of an apparent m.w. of approximately 10,000. FAF-M and FAF-U937 were acidic by isoelectric focusing with respective pI values of 4.0 to 5.2 and 5.4 to 5.6. The smaller factors from both sources filtered on Sephadex G-25 in phosphate-buffered saline with an apparent m.w. of 10,000. However, filtration of the same factors on Sephadex G-25 in 0.1 M acetic acid revealed one predominant fibroblast-activating activity for each cell source of an apparent m.w. of 500 to 1000. The 500 to 1000 dalton factors were inactivated by treatment with trypsin and subtilisin, suggesting that the activity was attributable to fibroblast-activating peptides, termed FAP-M and FAP-U937. FAP-M and FAP-U937 each appeared to be composed of a predominant hydrophilic activity by reverse-phase high-performance liquid chromatography. Human blood monocytes and U937 monocytes both produce structurally diverse fibroblast-activating proteins and peptides, which may contribute to the immunologic regulation of wound healing and fibrosis.

Cell Line↗

Characteristics of the epitope of leukotriene B4 recognized by a highly specific mouse monoclonal antibody.

Mouse monoclonal IgG2b antibodies to leukotriene B4 bind [3H]leukotriene B4 with an affinity one-thirtieth to one-third that of different rabbit antibodies to leukotriene B4. The concentrations of related ligands required to inhibit by 50% the binding of [3H]leukotriene B4 define cross-reactivities of approximately 100% for carboxyl-derivatives of leukotriene B4, 10% for 12(S)-leukotriene B4 and 8 cis-leukotriene B4, which were not distinguished from leukotriene B4 by polyclonal antibodies, 3-5% for the two isomers of 6 trans-leukotriene B4, 5% for 20-OH-leukotriene B4 and 20-COOH-leukotriene B4, and less than 1% for other leukotrienes, mono-hydroxy-eicosatetraenoic acids, and the two leukotriene B4-like isomers of 8, 15-di-hydroxy-eicosatetraenoic acid. Thus the monoclonal combining site is highly specific for the di-hydroxy-triene portion of leukotriene B4.

Antibodies, Monoclonal↗

Leukotriene B4 produces hyperalgesia that is dependent on polymorphonuclear leukocytes.

Leukotriene B4, at the same intracutaneous doses as bradykinin, reduced the nociceptive threshold in the rat paw. The mechanism of leukotriene B4-induced hyperalgesia was distinguished from that of the hyperalgesia elicited by prostaglandin E2 and bradykinin by its dependence on polymorphonuclear leukocytes and independence of the cyclooxygenation of arachidonic acid.

Analgesics↗

Inhibition by somatostatin of the proliferation of T-lymphocytes and Molt-4 lymphoblasts.

The proliferation of Molt-4 lymphoblasts and phytohemagglutinin-stimulated human T lymphocytes in vitro was inhibited significantly by 10(-12) to 10(-10) M to 10(-13) to 10(-9) M somatostatin, as assessed by the uptake of [3H]thymidine and [3H]leucine, respectively. The inhibitory effect of somatostatin was not attributable to cytotoxicity and was associated with a mean degradation of 52 and over 95% of immunoreactive somatostatin, respectively, after 3 and 24 hr of incubation at 37 degrees C. The specific suppression of Molt-4 lymphoblasts and T lymphocytes by somatostatin represents a distinct mechanism for the specific regulation of immunological responses by neuropeptides of the peripheral nervous system and gastrointestinal tract.

Cell Line↗

Heterogeneity of human polymorphonuclear leukocyte receptors for leukotriene B4. Identification of a subset of high affinity receptors that transduce the chemotactic response.

Human polymorphonuclear (PMN) leukocytes bound [3H]leukotriene B4 ([3H]-LTB4) specifically, as assessed by the displacement of 88% or more of the bound radioactivity by a 15,000-fold higher concentration of nonradioactive LTB4 or by micromolar concentrations of structural isomers of LTB4. The specific binding of [3H]LTB4 by PMN leukocytes was characterized by rapid association and dissociation, and was saturable at 800 nM LTB4. The results of computer analyses of the concentration dependence of binding of [3H]LTB4 were consistent with the expression of two classes of receptors having respective mean affinities of 3.9 X 10(-10) M and 6.1 X 10(-8) M and mean densities of 4.4 X 10(3) and 2.7 X 10(5) per PMN leukocyte. Structural isomers of LTB4 inhibited the binding of [3H]LTB4 to PMN leukocytes at concentrations similar to those required to elicit chemotaxis, while chemotactic peptides did not inhibit binding. PMN leukocytes that were deactivated by prior exposure to LTB4 lost high affinity binding sites selectively and concurrently with a reduction in the chemotactic response to LTB4. Chemotactic deactivation altered, but did not eliminate, the low affinity receptors for LTB4 and reduced only minimally the lysosomal degranulation elicited by LTB4. The high affinity receptors for LTB4 on normal human PMN leukocytes appear to transduce the chemotaxis evoked by LTB4 without substantially modifying lysosomal degranulation.

12-Hydroxy-5,8,10,14-eicosatetraenoic Acid↗

Immunopathogenetic roles of leukotrienes in human diseases.

The recent definition of the pathways of generation and structures of diverse products of the lipoxygenation of arachidonic acid has established the identity of a new family of mediators of hypersensitivity and inflammation. Studies of the effects of these mediators have shown that leukotrienes C, D, and E, the constitutents of the slow-reacting substance of anaphylaxis (SRS-A), are extremely potent smooth muscle contractile and vasoactive factors. Leukotriene B is a highly active stimulus of neutrophil and eosinophil functions and suppresses the immunological capabilities of T lymphocytes. The development of specific and sensitive radioimmunoassays has permitted the detection of elevated concentrations of leukotrienes in tissues or exudates in several diseases, including asthma, diverse allergic states, adult respiratory distress syndrome, psoriasis, spondyloarthritis, and gout. The application of selective inhibitors and antagonists of leukotrienes will clarify their pathogenetic contributions in human diseases and may yield new therapeutic approaches.

Arachidonate Lipoxygenases↗

Elevated concentrations of leukotriene D4 in pulmonary edema fluid of patients with the adult respiratory distress syndrome.

The possible contribution of metabolites of arachidonic acid to the increased permeability of the alveolar-capillary barrier in the adult respiratory distress syndrome was examined by quantifying the pulmonary edema fluid concentrations of lipoxygenase and cyclooxygenase products. The concentration of leukotriene D4 in pulmonary edema fluid of 10 patients with the adult respiratory distress syndrome (18.5 +/- 6.8 pmol/ml; mean +/- SD), assessed by specific radioimmunoassay after isolation of the mediator, was significantly higher (P less than 0.001) than that of five patients with cardiogenic pulmonary edema (4.4 +/- 1.1 pmol/ml). The concentrations of leukotrienes B4 and C4, prostaglandin E2, and thromboxane B2 in edema fluid were not significantly different in the adult respiratory distress syndrome patients than in the other subjects with pulmonary edema. The edema fluid concentration of leukotriene D4 correlated with the ratio of edema fluid to plasma concentrations of albumin (r = 0.64). Leukotriene D4 thus may contribute to the permeability defect which allows an accumulation of protein-rich alveolar fluid in the adult respiratory distress syndrome.

Adolescent↗

Indomethacin enhances the proliferation of mitogen-stimulated T lymphocytes of homosexual males with persistent generalized lymphadenopathy.

The possibility that cyclooxygenase products of arachidonic acid might contribute to the defective T lymphocyte function of homosexual men with the reactive lymph node syndrome was examined in vitro. T lymphocyte proliferation, assessed by the uptake of [3H]thymidine after the addition of phytohemagglutin, was 72,870 +/- 66,816 counts per minute (mean +/- SD) for eight patients and 119,589 +/- 64,913 counts per minute for 30 controls (P less than 0.05, Student's t test). Treatment with the cyclooxygenase inhibitor indomethacin increased the phytohemagglutin-induced proliferation of the T lymphocytes from five of eight patients, but none of 12 healthy homosexual and heterosexual control subjects. The production of prostaglandin E2 by T lymphocytes from six patients was 16.1 +/- 10.5 pg/5 X 10(6) cells/hr, as contrasted with that of 4.9 +/- 1.3 and 4.3 +/- 2.1 pg/5 X 10(6) cells for four healthy homosexual and six healthy heterosexual control subjects, respectively (P less than 0.01, Student's t test). The production of prostaglandin E2 by the patients' monocytes was normal. Abnormalities of the cyclooxygenase pathway of T lymphocytes of patients with the reactive lymph node syndrome may reflect an immunoregulatory defect, which predisposes to infections and may evolve into the more severe abnormalities of the acquired immune deficiency syndrome.

Acquired Immunodeficiency Syndrome↗

Prostaglandin-generating factor of anaphylaxis induces mucous glycoprotein release and the formation of lipoxygenase products of arachidonate from human airways.

The effects of prostaglandin-generating factor of anaphylaxis (PGF-A) upon the lipoxygenation of arachidonic acid and the promotion of mucous glycoprotein secretion by human airways were analyzed concurrently in order to determine the role that lipoxygenase products play in the secretion of mucus which accompanies immediate hypersensitivity reactions of airways. PGF-A enhanced both mucous glycoprotein release and the 5- and 15-lipoxygenation of arachidonic acid as well as the formation of leukotriene B4 (LTB4) with similar dose-response relationships. The capacity of PGF-A to stimulate mucous glycoprotein release was inhibited by ETYA but not by indomethacin, suggesting that PGF-A stimulated lipoxygenase products may be involved. Lipoxygenase products of arachidonic acid thus may serve as mediators of the enhancement of mucus secretion from human airways in response to PGF-A.

5,8,11,14-Eicosatetraynoic Acid↗

Selective transduction of human polymorphonuclear leukocyte functions by subsets of receptors for leukotriene B4.

Human polymorphonuclear leukocytes express two classes of receptors specific for leukotriene B4 (LTB4). The binding of LTB4 to the high-affinity, low-capacity receptors is critical in eliciting a chemotactic response, as assessed by the stereospecificity of binding and the loss of expression of high-affinity receptors after chemotactic deactivation. The stereospecificity and concentration dependence of LTB4 stimulation of granular enzyme release suggest that the low-affinity, high-capacity receptors mediate this response. Although the LTB4 receptors exhibit properties similar to those of the receptors for peptide chemotactic stimuli, the expression of both classes of receptors on intact polymorphonuclear leukocytes will permit a more complete assessment of the coupling of receptor occupancy to functional activation and the delineation of LTB4 receptor-level defects in human disease states.

Chemotaxis, Leukocyte↗