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P Kuna

Publications and source records attributed to P Kuna.

At least 55 records · Page 3Linked to original sources
PubMed1996

Further characterization of histamine releasing chemokines present in fractionated supernatants derived from human mononuclear cells.

BACKGROUND: Histamine releasing factors (HRF) are members of the beta chemokine family of cytokines and have been characterized using recombinant proteins. Mononuclear cell and/or platelet supernatants have been shown to contain HRF and the initial void peak obtained using Mono Q anion exchange chromatography possesses such activity, as do two later peaks eluted from the column. OBJECTIVE: We wished to further characterize the activity present in the void peak and determine which of the chemokines present are responsible for the activity measured. METHODS: We fractionated the void peak obtained from Mono Q chromatography on Mono S. The elution profile of individual chemokines was determined and the fractions were assayed for histamine releasing capability. We used monospecific antisera to inhibit the activity and quantitate the contribution of each protein. RESULTS: The fractions contained MCP-1/MCAF, CTAPIII/NAP-2, IL8, and a small quantity of RANTES. About 90-95% of the total histamine containing capability was attributable to MCP-1/MCAF. There was a small contribution by CTAPIII/NAP-2, and RANTES, and no activity associated with IL8. CONCLUSION: MCP-1/MCAF is the critical HRF present in the initial void peak obtained by anion exchange chromatography of supernatants derived from human mononuclear cells and platelets. The alpha chemokine CTAPIII/NAP-2 has relatively weak activity and IL8 has none although they are prominent in this fraction and overlap with MCP-1/MCAF. RANTES makes a minor contribution but most of it is eluted in a later peak.

Antibodies, Monoclonal↗
PubMed1996

[The effect of specific immunotherapy on the concentration of some chemokines in BALF in patients with atopic bronchial asthma].

The cellular basis the mechanism of specific hyposensitization is still unclear. We studied the effect of immunotherapy on activity of interleukin-8 (IL-8) and monocyte activating and chemoattractant protein (MCAF/MCP1) in bronchoalveolar lavage fluid (BALF). 20 patients with atopic asthma took part in this study. 14 were treated with grass pollen extracts (Allergovit, Allergopharma, Germany) for 7 weeks and 6 of this group were not treated and served as control group. ELISA test (R&D, USA) was used to assess IL-8 and MCAF/MCP1 activity in one ml of BALF recovered before and after immunotherapy. The results indicate that immunotherapy induces the suppression of MCAF/MCP1 production and the increase of IL-8 production in BALF. These chemokines may have reciprocal control on inflammatory cells, which participate in creating of inflammatory changes in asthma.

Adult↗
PubMed1995

Chemokines of the alpha, beta-subclass inhibit human basophils' responsiveness to monocyte chemotactic and activating factor/monocyte chemoattractant protein-1.

Monocyte chemotactic and activating factor (MCAF) is the most potent cytokine that activates basophils to release histamine. The response of human basophils to either simultaneous or sequential addition of the chemokines RANTES, macrophage inflammatory protein (MIP)-1 alpha, MIP-1 beta, platelet factor (PF)4, connective tissue activating peptide III (CTAP-III), interleukin (IL)-8, and inflammatory protein (IP)-10 on MCAF-induced histamine release was studied. Simultaneous addition of MCAF and any of the chemokines studied evoked an augmented response as measured by histamine release, whereas preincubation of leukocytes or purified basophils (80%) with these chemokines decreased MCAF-induced histamine release in a dose-dependent manner. Histamine release by anti-IgE remained unchanged. When tested at 5 x 10(-9) mol/L, the decrease in histamine release by RANTES was 69.2% +/- 3.5%, by MIP-1 alpha 48.8% +/- 3.1%, by MIP-1 beta 42.9% +/- 3.1%, by PF4 56.5% +/- 2.9%, by IL-8 41.2% +/- 2.2, by CTAP III 27% +/- 4.4%, and by IP-10 15.3% +/- 2.6%. The peak inhibition of histamine release by the chemokines was reached within 10 minutes of preincubation with basophils and remained unchanged thereafter. Washing basophils after preincubation with chemokines abolished the inhibition, with the exception of desensitization by low concentrations of MCAF. With the exclusion of MCAF and RANTES, none of the chemokines (at the concentration range of 5 x 10(-8) to 5 x 10(-11)) induced significant (> 10% above spontaneous) histamine release from basophils. Preincubation of basophils with C5a (5 x 10(-10) mol/L) did not affect histamine release, whereas preincubation with granulocyte-macrophage colony-stimulating factor (10 ng/ml) or IL-5 (10 ng/ml) enhanced MCAF-induced histamine release by 121.8% +/- 10.1% and 108% +/- 10.8%, respectively. We have therefore characterized RANTES, MIP-1 alpha, MIP-1 beta, CTAP III, PF4, IL-8, and IP-10 as inhibitors of MCAF-induced histamine release. Although the results are consistent with receptor blockade, the alpha and beta chemokines appear to interact with separate receptors linked to G proteins; thus, a mechanism of receptor class desensitization is proposed. Interaction of this group of cytokines at the site of allergic inflammation may modulate a function of basophils to initiate, augment, or inhibit histamine release.

Basophils↗
PubMed1995

Effects of PBMC-derived histamine-releasing factors on histamine release from human skin and lung mast cells.

BACKGROUND: A field of study which has attracted much recent interest is the ability of mononuclear cells and neutrophils to interact with histamine releasing cells by production of specific histamine releasing factors (HRFs). However, almost all of these studies have been performed on basophils rather than human mast cells. OBJECTIVE: We have investigated the effects of lyophilized fractions of HRF preparations on histamine release from human skin and lung mast cells. METHODS: Lyophilized fractions of HRF preparations include crude supernatant from mononuclear cell/platelet (crude), void peak from anion exchange chromatography column (void), second peak from anion exchange chromatography (peak 2), neutrophil-activating peptide-2 (NAP-2), which was purified from void peak at molecular weight of 8-12 kDa, and monocyte chemotactic-activating factor (MCAF). Mast cells were enzymatically dispersed. RESULTS: Crude (24.2 micrograms/mL-2.42 mg/mL), void (5.4 micrograms/mL-0.54 mg/mL), peak 2 (3.5 micrograms/mL-0.35 mg/mL), and NAP-2 (1-20 micrograms/mL) failed to release histamine from lung mast cells. In skin mast cells, only higher concentrations of crude and void caused minimal release of histamine. MCAF up to micromolar concentrations failed to have an effect on mast cells from either source. However, these HRFs induced histamine release from human basophils. We also explored whether HRFs and stem cell factor could act as either priming agents for each other or for anti-IgE. The response of skin mast cells to all these preparations was not enhanced by preincubation in stem cell factor at 1 ng/mL, nor did the HRFs and MCAF enhance the response of skin mast cells to anti-IgE. CONCLUSION: These results suggest that these HRFs have no significant effect on dispersed human cutaneous and lung mast cells.

Basophils↗
PubMed1995

Chemokines and the allergic response.

The beta subfamily of chemokines contains cytokine-like factors which are chemotactic for human basophils and eosinophils. The also stimulate these cells to secrete pro-inflammatory substances such as histamine or eosinophil cationic protein. MCAF/MCP-1, MCP-2, MCP-3, RANTES and MIP-1 alpha all attract and stimulate basophils; MCP-1 and MCP-3 are the most potent. RANTES, MCP-3 and to a lesser degree MIP-I alpha are chemotactic factors and activators of eosinophils. Cytokines such as IL3, IL5 and GM CSF can augment the responses of these cells to the various chemokines and function as primers. These substances may have particular importance as mediators of allergic inflammation, particularly the late phase component of the response.

Animals↗
PubMed1993

Characterization of the human basophil response to cytokines, growth factors, and histamine releasing factors of the intercrine/chemokine family.

We have tested the histamine releasing properties and priming abilities of a wide range of recombinant or purified cytokines and growth factors on the basophils of 20 subjects (10 atopic and 10 nonatopic). We found that monocyte chemotactic and activating factor/monocyte chemoattractant protein-1 (MCAF/MCP-1), RANTES, human macrophage inflammatory protein-1 alpha and human inflammatory protein-1 beta, Connective tissue activating peptide III and Neutrophil Activating Peptide-2 (NAP-2) cause histamine release from basophils and are all members of the intercrine/chemokine family. MCAF/MCP-1 was as potent as anti-IgE or C5a and it is clearly the major contributor to histamine releasing factor activity. RANTES was the second major histamine releasing factor among the positive cytokines. Both MCAF/MCP-1 and RANTES are present in conditioned mononuclear cell media and can be separated using Mono Q anion exchange chromatography. We also demonstrated that RANTES has unusual chromatographic properties in spite of its isoelectric point of > 9.0 because it is largely found in peak-2 of the Mono Q column rather than peak-1 in which intercrines such as MCAF/MCP-1, IL-8, and connective tissue activating peptide III are found. All other cytokines and growth factors tested were negative, with the exception of IL-3, which caused histamine release in a subpopulation of subjects, and also primed basophils for release by anti-IgE. Other basophil primers for anti-IgE-dependent histamine release were IL-5, mast cell growth factor (c-kit ligand), and insulin-like growth factor II. Using specific neutralizing antibodies we have shown that MCAF/MCP-1, RANTES, and IL-3 contribute significantly to the activity found in mononuclear cell culture supernatants. Granulocyte-macrophage-CSF, IP-10, I-309, IL-7, IL-8, IL-9, IL-10, IL-11, IgE-binding factor, TNF-alpha, TGF-beta 1, fibroblast growth factor, epidermal growth factor, and endothelial cell growth factor were negative for direct histamine release and as primers of basophils. Our results indicate that cytokines belonging to the intercrine/chemokine family are major constituents of the activity known as "histamine releasing factor" found in MNC supernatants.

Animals↗
PubMed1993

Human high molecular weight kininogen binds to human umbilical vein endothelial cells via its heavy and light chains.

High molecular weight kininogen (HK) is a multifunctional plasma glycoprotein that occupies a critical position in pathways that link inflammation and coagulation. Excision of the vasoactive peptide bradykinin by plasma kallikrein results in kinin-free HK that consists of a 65-Kd N-terminal heavy chain (HK-HC) linked to the C-terminal 45-Kd light chain (HK-LC) by a disulfide bridge. HK-HC is an inhibitor of SH-proteases and HK-LC contains the binding sites for coagulation cofactors prekallikrein and factor XI. HK has previously been shown to bind specifically to human umbilical vein endothelial cells (HUVEC) in a zinc(2+)-dependent manner by a single class of high-affinity binding sites. We have further characterized that interaction in order to determine the cell-binding regions of HK. Competition binding experiments have indicated that either HK-LC or HK-HC was able to inhibit the binding of labeled HK with a 50% inhibitory concentration (IC50) of 77 nmol/L and 89 nmol/L, respectively. Cleaved two-chain HK (HKa) had an IC50 of 73 nmol/L, whereas uncleaved HK had an IC50 of 335 nmol/L. Direct binding experiments have indicated that HUVEC bind both purified [125I]HK-HC and [125I]HK-LC in a zinc(2+)-dependent manner and that HK-LC did not displace bound HK-HC. The light chain of low molecular weight kininogen or prekallikrein-binding region of HK did not inhibit the binding of HK to HUVEC. Our results, therefore, indicate that (1) HK is capable of binding to endothelial cells via both heavy and light chain moieties, (2) HKa has a higher affinity to HUVEC, and (3) purified heavy and light chains are capable of directly binding to HUVEC. The data are consistent with the presence of a single high-affinity site for HK on endothelial cells within which are subsites that bind to heavy and light chains.

Binding Sites↗
PubMed1992

Generation of vasoactive peptide bradykinin from human umbilical vein endothelium-bound high molecular weight kininogen by plasma kallikrein.

High molecular weight kininogen (HK) is a multifunctional plasma glycoprotein that occupies a critical position in pathways that link inflammation and coagulation. It is an inhibitor of sulfhydryl proteases and has procoagulant properties. It is also a source of the vasoactive peptide bradykinin (BK). It has been previously shown that HK binds to human umbilical vein endothelial cells (HUVEC) in culture. We have further characterized that interaction herein. Immunohistochemical experiments have indicated that when freshly obtained umbilical vein segments were treated with HK, washed, and probed with anti-HK antibodies, HK was localized on the endothelium. We next determined whether HUVEC-bound HK can be cleaved by plasma kallikrein to release BK. Cultured HUVEC were incubated with unlabeled HK for varying times, washed, and the kinetics of BK release by plasma kallikrein were assayed by radioimmunoassay. Results indicated that kallikrein released BK from HUVEC in proportion to the initial amount of bound HK. No release of BK occurred in the absence of kallikrein. Also, there was no BK release upon kallikrein treatment of the HUVEC not treated with exogenous HK. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography of HUVEC-bound 125I-HK indicated that addition of kallikrein resulted in cleavage of HK, thus corroborating the BK release experiments. Comparison of cleavage patterns has also indicated that cell-bound HK is slightly less susceptible to digestion by kallikrein than free HK. Therefore, our data suggest that human HK can bind to vascular endothelium in situ and that plasma kallikrein can recognize endothelial-bound HK as a substrate and liberate the vasoactive peptide BK.

Amino Acid Sequence↗
PubMed1992

RANTES, a monocyte and T lymphocyte chemotactic cytokine releases histamine from human basophils.

Chemotaxis of different populations of cells and release of proinflammatory mediators in response to antigenic stimulation are important processes in allergic diseases. These lead to the late phase response, a hallmark of chronic allergic diseases. Recombinant RANTES, a member of the "intercrine/chemokine" family of cytokines, has been previously shown to be chemotactic for monocytes and T cells of memory/helper phenotype. In this manuscript, we show that it is capable of inducing histamine release from human basophils at concentrations as low as 10(-10) M and compare its activity with that of monocyte chemotactic and activating factor/monocyte chemoattractant protein-1 (MCAF/MCP-1), another intercrine/chemokine. RANTES (10(-7) M) caused histamine release from the leukocytes of 26 of 33 donors tested (mean 21.8 +/- 3.1%). In the same group of donors, MCAF/MCP-1, goat anti-human IgE (anti-IgE; 1 microgram/ml), and FMLP (10(-5) M) released 41.1 +/- 2.9%, 40.5 +/- 4.6%, and 44 +/- 3.1% histamine, respectively. The percent histamine release by RANTES in atopic vs nonatopics was 30.3 +/- 6.7 and 16.5 +/- 2.4, respectively (p less than 0.05), and histamine release by RANTES correlated significantly with histamine release by MCAF (r = 0.69; p less than 0.001) but not with histamine release by anti-IgE (r = 0.29; p greater than 0.05). Histamine release by RANTES and MCAF/MCP-1 was extremely rapid, reaching a maximum within 1 min. RANTES was also shown to activate highly purified basophils (80% pure), and its activity was inhibited by a polyclonal anti-RANTES antibody. At a suboptimal concentration (6 x 10(-9) M), RANTES did not prime basophils to enhance histamine release by secretagogues such as anti-IgE, C5a, or FMLP. On the other hand, preincubation of basophils with RANTES or MCAF/MCP-1 desensitized basophils to either factor but not to anti-IgE, C5a, or FMLP. Preincubation of basophils with pertussis toxin markedly diminished the basophil response to either RANTES or MCAF/MCP-1. These results suggest that RANTES and MCAF/MCP-1: 1) are potent activators of basophils; 2) may function via the same, or a closely related, receptor system in basophils; and 3) may represent a link between activation of monocytes, lymphocytes, and basophils in inflammatory disorders such as the late phase allergic reaction.

Basophils↗
PubMed1992

Monocyte chemotactic and activating factor is a potent histamine-releasing factor for human basophils.

Recombinant monocyte chemotactic-activating factor (MCAF) has been shown to induce histamine release from human basophils with a dose response between 10(-9) and 10(-6) M. The peak of activity was reached at 10(-7) M. Histamine release by MCAF was rapid with an initial rate comparable with histamine release by an optimal dose of anti-IgE. MCAF led to peak histamine release within 1 min. 80% of the subjects tested were responsive to MCAF or anti-IgE, while all were responsive to FMLP. The percentage histamine release by MCAF was, however, less than that seen with anti-IgE or FMLP, but this was attributable to a lesser percent release in nonatopic subjects; atopic subjects responded similarly to all three agonists. MCAF was also shown to activate highly purified human basophils more readily than mixed leukocytes, and its activity was inhibited by a polyclonal rabbit antibody. At a suboptimal concentration (2.5 x 10(-9) M), MCAF was unable to prime the basophil to histamine release by other secretagogues. However, interleukin 3 (IL-3) and IL-5 could each prime basophils for MCAF-induced secretion. Therefore, our results suggest that MCAF may be a major contributor to the histamine-releasing activity seen in peripheral blood mononuclear cell supernatants that has been designated histamine releasing factor(s).

Allergens↗
PubMed1992

Connective tissue-activating peptide-III and its derivative, neutrophil-activating peptide-2, release histamine from human basophils.

Connective tissue-activating peptide-III (CTAP-III) is a 9 kd platelet alpha-granule-derived growth factor. It stimulates the synthesis of DNA, hyaluronic acid, glycosaminoglycans, and proteoglycan core protein in human fibroblasts. Human mononuclear cell-derived proteases have been previously demonstrated to digest the N-terminal 15 residues of CTAP-III (total, 85 residues) to produce neutrophil-activating peptide-2 (NAP-2). CTAP-III and NAP-2 belong to a class of proteins (platelet factor 4, interleukin-8/NAP-1, etc.) associated with inflammation and wound repair. In our efforts to purify human mononuclear cells and platelet-derived histamine-releasing factors, we had previously discovered that mixtures of CTAP-III and NAP-2 released histamine from human basophils. We have now developed simple protocols for the purification of CTAP-III and NAP-2, independently, from calcium ionophore (A23187)-stimulated platelet supernatants by affinity chromatography and have established their identity by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and N-terminal sequence analysis. Each of these related histamine between 2 and 10 micrograms/ml, a range identical to that obtained with CTAP-III/NAP-2 mixtures that we reported earlier. Thus, our data suggest that CTAP-III and NAP-2 independently release histamine from human basophils in dose ranges similar to ranges required for fibroblast stimulation by each.

Basophils↗