Influx of neutrophils into the airway lumen at 4 h after segmental allergen challenge in asthma.

BACKGROUND: Segmental allergen challenge is a powerful tool to study inflammatory reactions in asthmatic airways. There is little information on the early events at 5 min and 4 h after allergen challenge with respect to the cell influx and the chemokine interleukin-8 (IL-8). METHODS: Seven mild to moderate allergic asthmatics (AA group), 5 allergic nonasthmatics (ANA group) and 5 nonallergic controls underwent segmental allergen challenge, with allergen doses based upon skin reactivity. Bronchoalveolar lavage (BAL) samples were obtained before, 5 min and 4 h postchallenge, and were analyzed for cell numbers and differential counts, eosinophil and neutrophil chemotactic activity, and levels of IL-8. RESULTS: At 5 min postchallenge, no changes were observed compared to baseline. At 4 h postchallenge, an increase was found in the number of neutrophils and the levels of IL-8, which was dependent on the dose of allergen in the AA and ANA group. At the same allergen dose, the increases in neutrophils and levels of IL-8 were calculated to be 91 and 67 times higher, respectively, in AA than in ANA. Levels of IL-8 correlated with the number of neutrophils and with the in vitro neutrophil chemotactic activities in BAL fluid. CONCLUSIONS: Neutrophil chemotactic activity is increased in BAL fluid at 4 h after segmental allergen challenge. We suggest that apart from IgE-mediated mast cell degranulation, additional local factors in the airways determine the degree of IL-8 increase and neutrophil influx.     

Effect of a leukotriene B4 antagonist on substance P-induced granulocyte infiltration in mouse skin]

Substance P causes granulocyte (neutrophil and eosinophil) infiltration in mouse skin by inducing mast cell degranulation. However, the mediator responsible for this granulocyte infiltration has not been determined. In this study, we examined the effect of a leukotriene B4 (LTB4) antagonist ONO-4057 on substance P-induced granulocyte infiltration in the skin of BALB/c mice. Pretreatment with the LTB4 antagonist decreased substance P-induced neutrophil and eosinophil infiltrations in mouse skin at 6 h to the same extent that an inhibitor of mast cell degranulation disodium cromoglycate decreased those responses. The LTB4 antagonist also decreased substance P-induced neutrophil, but not eosinophil, infiltration in mouse skin at 24 h. We conclude that LTB4 is a major mast cell-derived chemotactic mediator for initiating substance P-induced neutrophil and eosinophil infiltrations in mouse skin.     

Neutrophil chemotactic activity in toluene diisocyanate (TDI)-induced asthma

We quantitated serum neutrophil chemotactic activity (NCA), which is associated with mast cell or basophil activation, to determine if mast cell or basophil mediators are released during bronchoprovocation-inhalation challenge with subirritant levels of toluene diisocyanate (TDI). Four subjects with suspected TDI-induced asthma and four mite-sensitive subjects with asthma who served as a comparison group were studied. NCA was measured in a multiwell, microchemotaxis chamber. Blood samples were collected, and FEV1 measurements were performed before challenge and at regular intervals during the subsequent 24 hours. Three of four workers clinically sensitive to TDI reacted to a subirritant TDI exposure. There was no increase in NCA during placebo challenges. NCA increased in the three TDI-sensitive workers during early and late asthmatic reactions in quantities proportional to the FEV1 decline. No increase in NCA was found during TDI exposures in the TDI-negative worker. Gel filtration analysis demonstrated the main NCA fraction eluted with macromolecules of an estimated molecular weight greater than 440,000 daltons. This characteristic is compatible with neutrophil chemotactic factor of basophil or mast cell origin. The kinetics of NCA release were similar in mite- and TDI-induced asthmatic reactions. A high correlation (r = 0.97; p = 0.0006) was obtained between the percent decrease in FEV1 during early asthmatic reactions and percent increase in NCA. These observations support the hypothesis that activation of mast cells or basophils is associated with TDI-induced early and late asthmatic reaction.     

Neutrophil chemotactic factor of anaphylaxis (NCF-A) release in aspirin-induced asthma

Neutrophil chemotactic activity (NCA) following oral challenge with aspirin (ASA) was determined in ASA-intolerant asthmatic subjects, and in ASA-tolerant asthmatic and normal subjects. There was a statistically significant fall in FEV₁ and a rise in NCA (P <0.01) following challenge in the ASA-sensitive subjects compared with that of the ASA-tolerant subjects and normal controls. No significant difference was observed between the latter two groups. The chemotactic factor identified in this study had a molecular weight greater than 150 000 which is consistent with NCF-A (neutrophil chemotactic factor of anaphylaxis). The ASA-induced fall in FEV₁ and rise in NCA was further studied in three of the ASA-intolerant asthmatic subjects, with and without pretreatment with inhaled sodium cromoglycate. In these subjects, the drug inhibited both the oral ASA-induced bronchoconstriction and the increase in neutrophil chemotactic activity. These results suggest that ASA-induced asthma involves mediator release from mast cells, as shown by the increase in NCA following ASA challenge and the protective effect of sodium cromoglycate which is considered to inhibit mast-cell degranulation.     

Leukocyte activation in allergen-induced late-phase asthmatic reactions

Some patients with allergen-induced asthma have both an early and late reaction to allergen (dual asthmatic reactions). To investigate the role of leukocyte activation in dual asthmatic reactions, we measured neutrophil chemotactic activity, percentages of neutrophil and monocyte complement rosettes, and one-second forced expiratory volume (FEV1) in 11 patients with allergen-induced dual asthmatic reactions after a challenge with allergen. To control for the effects of bronchoconstriction, the same studies were done after a challenge with methacholine. In all subjects there was a biphasic increase in neutrophil chemotactic activity and the percentages of neutrophil and monocyte complement rosettes, accompanied by a reduction in the FEV1. After methacholine, there were no significant changes in neutrophil chemotactic activity or percentages of complement rosettes, despite bronchoconstriction. Six patients with single-phase allergen-induced asthma had similar responses, but they were monophasic. We conclude that allergen-induced early and late asthmatic reactions are accompanied by activation of leukocytes and that these alterations probably reflect the release of mediators from mast cells rather than an effect of bronchoconstriction.     

Dopamine inhibition of histamine-mediated cutaneous responses

Several patients receiving dopamine for hypotension were skin tested for possible penicillin sensitivity. Not only were the penicillin skin tests negative but also the histamine control. On the possibility that dopamine might affect cutaneous histamine responses, we examined the effect of dopamine on histamine, antigen, morphine, and compound 48/80 skin responses. Both intradermal and intravenous dopamine selectively inhibited histamine but not antigen, morphine, or compound 48/80 skin responses, and the inhibition was in a dose-related fashion. This observation indicates that histamine should not be used to demonstrate dermal reactivity in patients receiving dopamine. The results of this study also suggest that histamine may not be the sole mast cell-derived mediator involved in the wheal-and-flare reaction characteristic of immediate-type skin tests since dopamine did not affect skin reactions caused by endogenous mast cell degranulation. Finally, the possible use of dopaminergic drugs in diseases with histamine-associated symptoms is discussed.     

Comparison of substance P-induced and compound 48/80-induced neutrophil infiltrations in mouse skin.

It has recently been shown that substance P induces neutrophil infiltration in the skin, which is mediated through mast cell degranulation. Since substance P activates both skin mast cells and vascular endothelial cells, we compared the potencies of substance P and a mast cell-degranulating agent, compound 48/80, which is inactive for vascular endothelial cells, in inducing neutrophil infiltration in mouse skin. We also examined the effect of the C-terminal peptide of substance P, SP6-11, which is active for vascular endothelial cells, on compound 48/80-induced neutrophil infiltration in the skin. Subcutaneous administrations of substance P (10(-7) to 10(-5) M; 0.1 ml) and compound 48/80 (0.5-50 micrograms/ml) induced neutrophil infiltrations and mast cell degranulations in mouse skin in a concentration-dependent fashion. Moreover, substance P induced more neutrophil infiltrations than compound 48/80 in terms of the magnitude of mast cell degranulations. SP6-11 (10(-6) to 10(-4) M) induced no significant neutrophil infiltration or mast cell degranulation, but increased the vascular permeability of endothelial cells in the skin. Furthermore, SP6-11 enhanced compound 48/80-induced neutrophil infiltration without any increase in mast cell degranulation. Our results indicate that, in addition to mast cell degranulation, the activation of vascular endothelial cells is involved in substance P-induced neutrophil infiltration in the skin.     

An eosinophilotactic factor derived from rat mast cells.

Rat eosinophils have been showed to respond chemotactically to the supernatant from mast cells which have been disrupted by freezing and thawing and from mast cells which have been specifically degranulated by Compound 48/80 or by antigen challenge or sensitised cells. The fact that the chemotactic response is not dependent on allergic degranulation suggests that the chemotactic factor is present pre-formed in the mast cells rather than being generated in response to an antigen-antibody reaction.     

Delayed vibratory angioedema: Insights into pathophysiologic mechanisms

Plasma histamine levels and the histologic, electronmicroscopic, and immunofluorescent analysis of skin biopsy specimens were examined during the development of vibration-induced angioedema in two patients. The reactions to vibration in these patients were characterized by (1) clinical angioedema peaking 4 to 6 hours after challenge, (2) evidence of mast cell degranulation as indicated biochemically by an early and late increase in plasma histamine and histologically by exocytosis of mast cell granules, (3) a progressive infiltration of inflammatory cells, coinciding with the peak clinical reaction, and (4) an absence of the immunoreactants IgG, IgM, IgA, C3, and fibrinogen. The reactions in both patients were morphologically and biochemically similar to the cutaneous late-phase allergic reactions that occur after IgE-mediated, antigen-provoked mast cell degranulation. These studies suggest that vibratory angioedema is a manifestation of mast cell-induced cutaneous late-phase reactions.     

Failure of sulfites to produce clinical responses in patients with systemic mastocytosis or recurrent anaphylaxis: Results of a single-blind study

Although sulfite sensitivity can precipitate asthma in a subpopulation of subjects with asthma, its role in precipitating anaphylaxis or as a nonspecific mast cell degranulator in systemic mastocytosis has not been examined. To evaluate critically the importance of sulfites in these diseases, eight patients with systemic mastocytosis and 25 patients with unexplained, recurrent anaphylaxis were challenged in a single-blind fashion; sodium bisulfite in capsules was administered in increasing doses of 1, 5, 10, 25, 50, 100, and 200 mg every 30 minutes. On separate occasions a liquid suspension of 200 mg of sodium bisulfite was administered to one patient with systemic mastocytosis and nine patients with anaphylaxis. Vital signs, pulmonary function tests, plasma histamine levels, and clinical reactions were monitored. There were no observable responses in either the mastocytosis group or in 23 of 25 patients in the anaphylaxis group. Two patients in the anaphylaxis group with initial positive challenges had similar symptoms on subsequent placebo challenge. One subject with asthma and with a history suggestive of sulfite sensitivity responded to oral challenge with 5 mg of sodium bisulfite and 100 micrograms of sodium bisulfite intradermally with a dramatic reduction in FEV, requiring treatment with bronchodilators. A comparison of baseline plasma histamine levels with those obtained after the sulfite challenge procedure in each category demonstrated a significant rise (p less than 0.05) in the systemic mastocytosis group. The overall level of significance determined by applying paired sample t tests to the histamine data from all subjects was p less than 0.01.(ABSTRACT TRUNCATED AT 250 WORDS)     

Induction of human cutaneous mast cell degranulation by opiates and endogenous opioid peptides: Evidence for opiate and nonopiate receptor participation

In order to examine the capacity of pharmacologically useful opiates to stimulate human mast cell secretion, subjects were skin tested with morphine, codeine, or meperidine hydrochloride. All three agents acted equipotently in eliciting positive immediate skin reactions from all subjects tested. Each agent demonstrated 10 mm of net whealing at 5 to 10 micrograms base (16.7 to 40.4 nmol) injected intradermally. The ability to elicit immediate skin test reactions with endogenous opioid peptides was examined with the use of dynorphin, [D-Ala, 2-D-Leu5] enkephalin, beta-endorphin, and morphiceptin . All four compounds induced wheal-and-flare reactions with the order of potency: dynorphin, greater than beta-endorphin, and greater than [D-Ala, 2-D-Leu5] enkephalin approximately equal to morphiceptin at dose ranges of 0.3 to 8.45 nmol. The inhibition of reactivity by hydroxyzine and the demonstration of mast cell degranulation by electron microscopy suggest that the immediate skin responses to opioid stimulation occur as a consequence of mast cell degranulation. Experiments with the opioid receptor antagonist, naloxone, suggest that both opioid and nonopioid receptors may be involved. These results imply that endogenous opioid peptides possibly may play a role in mast cell function and/or degradulation .     

Mast cell degranulation induced by lectins: effect on neutrophil recruitment

The mammalian lectin macrophage-derived neutrophil chemotactic factor (MNCF) and the plant lectin KM+ were characterized for their ability to activate and degranulate mast cells. The association between mast cell activation and the induction of neutrophil migration was also investigated. Incubation of rat peritoneal mast cells with these lectins resulted in degranulation and mediator release. By confocal microscopy, both lectins were evenly distributed on the cell surface. MNCF activated RBL-2H3 mast cells only if the cells had been sensitized with IgE. KM+ was able to activate either unsensitized or IgE sensitized RBL-2H3 cells. In microplate assays MNCF, but not KM+, bound to rat IgE. In rats that were depleted of mast cells, neutrophil recruitment by MNCF and KM+ were significantly reduced indicating that mast cell activation provides an amplification loop for the neutrophil recruitment induced by these lectins. The present study supports the concept that mammalian lectins play a fundamental role in innate immunity.     

The mediation of tissue eosinophilia in hypersensitivity reaction. I. Isolation of two different chemotactic factors from DNP-Ascaris extract-induced skin lesion in guinea-pig.

In an active cutaneous anaphylaxis induced by DNP-ascaris extract in guinea-pig, tissue eosinophilia manifested two phases; the early and mild phase became maximal in about 6 h, while the delayed and intense phase in 18-24 h. Skin extracts from the lesions exhibited chemotactic activities for eosinophils, respectively comparable to the intensity of tissue eosinophilia in each phase; and two different chemotactic factors for eosinophils of skin extracts were separated by gel filtration on Sephadex G-100. The mediation of the early phase seemed to be associated with a thermostable factor with amolefular weight of less than 1400; this factor seemed to be related to mast cell degranulation. The mediation of the delayed phase appeared to be associated with a thermolabile factor with a molecular weight of about 70,000, probably independent of mast cell degranulation; the factor was considered to be more significant than the thermostable factor, because the delayed tissue eosinophilia was more intense than the early tissue eosinophilia.     

A cathelicidin family of human antibacterial peptide LL-37 induces mast cell chemotaxis

The mast cell is one of the major effector cells in inflammatory reactions and can be found in most tissues throughout the body. During inflammation, an increase in the number of mast cells in the local milieu occurs, and such accumulation requires directed migration of this cell population. As it has previously been reported that the human cathelicidin-derived antibacterial peptide, LL-37, stimulates the degranulation of mast cells, we hypothesized that LL-37 could be a mast cell chemotaxin. The present study shows that LL-37 is a potent chemotactic factor for mast cells. The chemotactic response was dose-dependent and bell-shaped, reaching an optimal concentration of 5 microg/ml. In addition, checkerboard analysis showed that cell migration towards this peptide was chemotactic rather than chemokinetic. Moreover, Scatchard analysis using 125I-labelled LL-37-derived peptide revealed that LL-37 has at least two classes of receptors, namely high- and low-affinity receptors, on mast cells. Furthermore, the competitive binding assay suggested that LL-37 is unlikely to utilize formyl peptide receptor-like 1 (FPRL1), a functional LL-37 receptor for neutrophil and monocyte migration, on mast cells. In addition, the treatment of cells with pertussis toxin and phospholipase C inhibitor, U-73122, inhibited LL-37-mediated migration, indicating that LL-37 induces mast cell chemotaxis through a Gi protein-phospholipase C signalling pathway. These results show that besides its antibacterial activities, LL-37 may have the potential to recruit mast cells to inflammation foci.     

Frequency and significance of immediate contact reactions to peanut in peanut-sensitive children

BACKGROUND: Parents of atopic children frequently report, and are alarmed by, contact reactions to foods. Some schools restrict foods due to concerns regarding possible systemic reactions following contact in allergic children. OBJECTIVE: We aimed to determine the frequency with which peanut-sensitive children exhibited contact sensitivity to peanut butter and to assess the significance of such reactions. METHODS: One gram of peanut butter was applied directly to the skin of 281 children who were skin prick test (SPT) positive to peanut (immediate skin application food test; I-SAFT). The test was considered positive if one or more weals were present when the patch was removed after 15 min. A subset of children then underwent an open-label oral challenge with graded amounts of peanut protein. RESULTS: During 3515 clinic visits, 330 I-SAFT tests for peanut contact sensitivity were performed; 136 (41%) were positive. The mean SPT diameter was 10 mm in the I-SAFT-positive children and 8.5 mm in the I-SAFT-negative children (t-test, P<0.0001). No child had a systemic reaction following topical application of peanut butter. Eighty-four children had 85 oral challenges after blinded, placebo-controlled I-SAFT testing. Challenge was positive in 26/32 of those with a positive I-SAFT and negative in only 6/32. Challenge was also positive in 26/53 but negative in 27/53 of those with a negative I-SAFT (sensitivity 50%, specificity 82%, chi2, P=0.003). CONCLUSION: A minority of children sensitized to peanut (positive SPT) develop localized urticaria from prolonged skin contact with peanut butter. No tested subjects, including ones with systemic reactions upon oral challenge, developed a systemic reaction to prolonged skin exposure to peanut. Therefore, systemic reactions resulting from this mode of contact with peanut butter appear highly unlikely.     

Insect sting allergy with negative venom skin test responses

BACKGROUND: In our 1976 controlled venom immuno rapy trial, 33% of 182 patients with a history of systemic reactions to insect stings were excluded because of negative venom skin test responses. There have been reports of patients with negative skin test responses who have had severe reactions to subsequent stings. OBJECTIVE: Our aim is to increase awareness about the patient with a negative skin test response and insect sting allergy and to determine the frequency and significance of negative skin test responses in patients with a history of systemic reactions to insect stings. METHODS: We prospectively examined the prevalence of negative venom skin test responses in patients with a history of systemic reactions to stings. In patients who gave informed consent, we analyzed the outcome of retesting and sting challenge. RESULTS: Of 307 patients with positive histories screened for our sting challenge study, 208 (68%) had positive venom skin test responses (up to 1 microg/mL concentration), and 99 (32%) had negative venom skin test responses. In 36 (36%) of the 99 patients with negative skin test responses, the venom RAST result was a low positive (1-3 ng/mL), or repeat venom skin test responses were positive; another 7 (7%) patients had high venom-specific IgE antibody levels (4-243 ng/mL). Notably, 56 (57%) of 99 patients with positive histories and negative skin test responses had negative RAST results. In patients with positive skin test responses, sting challenges were performed in 141 of 196 patients, with 30 systemic reactions. Sting challenges were performed on 37 of 43 patients with negative skin test responses and positive venom-specific IgE and in 14 of 56 patients with negative skin test responses and negative RAST results. There were 11 patients with negative skin test responses who had systemic reactions to the challenge sting: 2 had negative RAST results, and 9 had positive RAST results at 1 ng/mL. The frequency of systemic reaction was 21% in patients with positive skin test responses and 22% in patients with negative skin test responses (24% in those with positive RAST results and 14% in those with negative RAST results). CONCLUSIONS: Venom skin test responses can be negative in patients who will subsequently experience another systemic sting reaction. Venom skin test responses are negative in many patients with a history of systemic allergic reactions to insect stings and may be associated with positive serologic test responses for venom-specific IgE antibodies (sometimes strongly positive results). Venom skin test responses should be repeated when negative, along with a serologic IgE antivenom test. Better diagnostic skin test reagents are urgently needed.     

Histological study of mast cells in the actively sensitized guinea pig lung and after challenge: effect of a corticosteroid

Although mast cells are sometimes considered to play a minor role in hypersensitivity reactions, we used a histological method to show the modifications in the guinea pig lung mast cell population in the course of such reactions. We sensitized guinea pigs with ovalbumin and studied the effect of the challenge with and without corticosteroid treatment. We observed that the mast cell count was not modified after sensitization but was decreased after challenge. Twenty-four hours after challenge, the number of mast cells returned to the control value, indicating a renewal of the mast cell pool. A second challenge, 1 week after the first, did not provoke the same mast cell degranulation, suggesting a non-responsiveness to aerosol antigen. Betamethasone dipropionate treatment protected mast cells against challenge: in treated guinea pigs, mast cell degranulation was prevented, and we did not observe any change in mast cell count after challenge. The present study was useful to show an effect of corticosteroids on mast cell degranulation in immediate hypersensitivity reactions in vivo.     

The diagnostic value of crude or boiled extracts to identify tolerant versus nontolerant lentil-sensitive children.

OBJECTIVE: The aim of this study was to compare two types of lentil extracts for use in skin prick tests for the diagnosis of lentil clinical allergy. METHODS: Thirty-six patients with a history of allergic reactions after the ingestion of lentils were skin tested with two types of lentil extracts at 0.05, 0.5, 5, and 10 mg/mL. Both extracts were extracted at 40 degrees C and afterward, one of them was boiled for 15 minutes. Thirty-three of these patients underwent oral challenges with lentils and three had a convincing recent history of lentil anaphylaxis. RESULTS: Twenty patients had a positive oral challenge; 13 were negative. Skin prick tests performed with the boiled extract at 0.5 and 5 mg/mL were positive in 96% and 100% of patients with positive food challenge, and in 31% and 85% of those with negative food challenge, respectively; positive skin test results were similar in both groups using the crude extract. Mean wheal sizes using the boiled extract at 0.5, 5, and 10 mg/mL were significantly greater in patients with a positive oral challenge than in those with a negative one (4.9, 6.8, and 7.4 mm versus 1.9, 3.5, and 5.1 mm, respectively; P < 0.05) These mean values were not statistically different using the crude extract. CONCLUSIONS: These data suggest that lentil extracts for the diagnosis of lentil hypersensitivity should be heated, since boiled extracts, used at a concentration of 0.5 or 5 mg/mL, best identify clinically sensitive individuals.     

The natural mediator for PMN emigration in inflammation. VIII. Production of leucoegresin-like chemotactic factor in reversed passive Arthus reactions in rats.

The mediation of tissue neutrophilia in the reversed passive Arthus reactions in rats was studied on extract from the skin lesions. Approximately 55 per cent of the neutrophil chemotactic activity in the reactions exhibiting a maximal tissue neutrophilia seemed to be associated with a leucoeresin-like chemotactic factor which can be absorbed by an immunoadsorbent chromatography with anti-rat IgG antibody. On the other hand, the neutrophil chemotactic activity, comparable to most of the remaining chemotactic activity, was reduced in complement-depleted conditions in which the intensity of tissue neutrophilia in the reactions was moderately decreased, suggesting a possible involvement of complement-derived chemotactic factors.     

Prevention of F‐actin assembly switches the response to SCF from chemotaxis to degranulation in human mast cells

Following antigen/IgE‐mediated aggregation of high affinity IgE‐receptors (FcεRI), mast cells (MCs) degranulate and release inflammatory mediators leading to the induction of allergic reactions including anaphylaxis. Migration of MCs to resident tissues and sites of inflammation is regulated by tissue chemotactic factors such as stem cell factor (SCF (KIT ligand)). Despite inducing similar early signaling events to antigen, chemotactic factors, including SCF, produce minimal degranulation in the absence of other stimuli. We therefore investigated whether processes regulating MC chemotaxis are rate limiting for MC mediator release. To investigate this issue, we disrupted actin polymerization, a requirement for MC chemotaxis, with latrunculin B and cytochalasin B, then examined chemotaxis and mediator release in human (hu)MCs induced by antigen or SCF. As expected, such disruption minimally affected early signaling pathways, but attenuated SCF‐induced human mast cell chemotaxis. In contrast, SCF, in the absence of other stimuli, induced substantial degranulation in a concentration‐dependent manner following actin disassembly. It also moderately enhanced antigen‐mediated human mast cell degranulation which was further enhanced in the presence of SCF. These observations suggest that processes regulating cell migration limit MC degranulation as a consequence of cytoskeletal reorganization.