Modulation of serum histamine releasing activity in chronic idiopathic urticaria.

BACKGROUND: Sera of about 30% of patients with chronic idiopathic urticaria (CIU) have increased histamine releasing activity (HRA+) on normal basophils. It is not known whether other CIU sera would be HRA+ if a more sensitive histamine release assay was used. Although most HRA+ CIU sera appear to have anti Fc(epsilon)R1 activity, it is not known whether post-binding basophil intracellular events are similar to those after anti-IgE stimulation. RESULTS: In the presence of D2O, the HR stimulated by 28 previously documented HRA- sera increased from 4+/-0.4 to 21+/-4% with 13 of the 28 sera now considered HRA+. No previous HRA sera was HRA+ with IL-3 treated cells. Histamine release induced by both HRA+ sera and anti-IgE were inhibited by genistein, and Ca2+/Mg2+ depletion but not by bisindoylmaleimide. HRA+ sera induced prominent HR from normal basophils with little surface IgE, but induced no increased HR from basophils unresponsive to anti-IgE. CONCLUSIONS: Up to 61% of CIU sera will induce increased HR from normal basophils in a sufficiently sensitive assay system. HR induced by most HRA+ sera is more prominent in basophils with very little surface IgE. However, there may be similar post-binding intracellular activation pathways following stimulation by HRA+ sera and anti-IgE.

Patterns of inflammatory responses following rechallenge of skin late-phase allergic reaction sites.

BACKGROUND: Previous studies have suggested altered responses to repeat skin tests in the sites of IgE-mediated late-phase reactions (LPRs) induced within the previous 48 hours. To explore the possible modulation of LPRs in such rechallenge sites, we compared inflammatory responses in skin chambers induced over previous LPR and control sites. METHODS: Skin blisters were induced and unroofed in 12 human subjects over two sites of previous LPRs induced by intradermal injection of pollen antigens 24 hours or 48 hours earlier and two sites previously injected with buffer diluent (B). Skin chambers containing the same antigens were appended to one intradermal antigen site (called Ag/Ag) and one intradermal B site (B/Ag), and B-containing chambers were placed over antigen (Ag/B) and B (B/B) intradermal sites. Fluids were collected after the first and the second through fifth hours of challenge. RESULTS: In skin chamber challenges 24 hours after the intradermal injection, there was no significant difference after the first hours between the Ag/Ag or B/Ag sites in either histamine or tryptase levels; both were significantly higher than at Ag/B or B/B sites (p < 0.01). The same pattern of events was seen in fluids obtained from the second through fifth hours. The same pattern of findings was seen in examination of levels of the total leukocyte accumulation, total eosinophil accumulation, and frequency of activated (EG2+) eosinophils. Levels of lactoferrin, released from activated neutrophils, and eosinophil cationic protein, released from activated eosinophils, were also similar at Ag/Ag and B/Ag sites; both were significantly higher than at B/B sites, whereas levels at Ag/B sites were intermediate between those found at B/Ag and B/B sites. The pattern of events in skin chamber challenges 48 hours after intradermal injection was similar to that seen at 24 hours, except that levels of inflammatory mediators/cells in Ag/B sites were more intermediate between the B/Ag and B/B sites. CONCLUSION: There is no significant alteration of mediator or inflammatory cell responses after antigen rechallenge of previous LPR sites when compared with those found in antigen challenge of non-LPR sites.

Cellular inflammatory responses during immediate, developing, and established late-phase allergic cutaneous reactions: effects of cetirizine.

BACKGROUND: In some previous studies, the antihistamine cetirizine has inhibited both developing (at 6 hours) and established (at 24 hours) gross late-phase skin reactions (LPR) to pollen antigens, possibly relevant to clinical drug effects. However, the effects of cetirizine at the histologic level require further definition. OBJECTIVE: To characterize cetirizine effects on gross and histologic inflammatory events from 20 minutes to 24 hours after intradermal antigen challenge in sensitive patients. METHODS: Gross and histologic responses to intradermal pollen antigen, codeine, histamine, and buffer diluent were assessed during randomized 7-day treatments with cetirizine and placebo. Accumulated neutrophils, eosinophils, activated (EG2+) eosinophils, and T lymphocytes were quantitated. The degrees of extracellular deposition of lactoferrin from neutrophils and eosinophilic cationic protein (ECP) from eosinophils were also assessed. RESULTS: During placebo treatment, wheal-and-flare responses were significantly greater to antigen at 20 minutes (p < 0.01) and induration at 6 hours (p < 0.01) at antigen challenge sites than at buffer diluent sites. During cetirizine treatment, these wheal-and-flare responses to antigen were inhibited significantly (p < 0.01) but gross LPRs were not affected. During placebo treatment, significantly more cells per high-power field were found in antigen sites than in buffer sites of neutrophils at 20 minutes (p < 0.01) and 24 hours; than in eosinophils at 20 minutes, 6 hours, and 24 hours (p < 0.01 for each); than in EG2+ cells at 20 minutes (p = 0.004), 6 hours (p = 0.001), and 24 hours (p = 0.02); and at T lymphocyte sites at 24 hours (p = 0.001). Extracellular deposition of lactoferrin and ECP was significantly greater at antigen sites than at buffer sites at 6 and 24 hours. Cetirizine treatment had no significant effect on these responses. CONCLUSION: Neutrophils, eosinophils, and T lymphocytes were persistently more common at antigen sites than at buffer sites through 24 hours. Many of these neutrophils and eosinophils were activated, releasing more lactoferrin and ECP into the extracellular dermis for at least 24 hours after antigen challenge. Cetirizine inhibited gross immediate responses to antigen, but not the gross LPR nor the cellular inflammatory responses seen in such LPR sites.

Cellular inflammatory responses and mediator release during early developing late-phase allergic cutaneous inflammatory responses: effects of cetirizine.

BACKGROUND: Events in developing cutaneous late-phase allergic reactions can be characterized by a combination of skin chamber and biopsy approaches. In some previous studies, cetirizine reportedly inhibited mediator release and/or inflammatory cell responses in late-phase reactions. OBJECTIVE: This study was carried out to determine the effects of cetirizine on early late-phase reactions by using skin chamber and skin biopsy specimens. METHODS: Skin chamber responses during a 6-hour challenge with pollen antigens were assessed in 15 sensitive subjects during randomized, crossover treatment with cetirizine (20 mg/day) or placebo for 7-day periods with measurements of humoral and cellular components. Biopsy specimens of the underlying dermis were obtained. RESULTS: During cetirizine treatment, there was significant (p < 0.01) inhibition of immediate wheal and flare reactions to pollen antigens (34, 46%), codeine (41, 65%), and histamine (38, 68%). However, gross late-phase reactions at 6 hours were unaffected. During both cetirizine and placebo treatment, there was significantly greater accumulation at antigen sites in: (1) skin chamber levels of histamine, total cells, lactoferrin, and eosinophil cationic protein; (2) eosinophils (total and activated) on appended cover glasses; (3) deposition of lactoferrin and eosinophil cationic protein in the underlying dermis. However, these responses were not significantly different during cetirizine treatment compared with placebo treatment periods. CONCLUSION: A persistent pattern of inflammatory cell accumulation with release of granule proteins during early late-phase reactions was unaffected by cetirizine treatment.

Characteristics of histamine-releasing activity in the sera of patients with chronic idiopathic urticaria.

BACKGROUND: The serum histamine-releasing activity (HRA) found in a sizable percentage of patients with chronic idiopathic urticaria (CIU) has been partially characterized. However, the variable effect of individual HRA+ sera in basophils of different donors and the relationship of HRA to the clinical course require further investigation. OBJECTIVE: The study was performed to characterize the HRA found in sera of some members of a sizable group of carefully evaluated patients with CIU. METHODS: Sera of 70 patients with CIU, evaluated with a standard protocol, were screened for increased HRA. HRA+ sera were fractionated, heated, and tested on unaltered and altered basophils obtained from a panel of normal donors. HRA levels were compared with concomitant clinical manifestations. RESULTS: HRA+ sera were found in 30% of our patients with CIU, HRA was predominantly in the IgG fraction, sensitive to 56 degrees C heating for 4 hours, and generally reacted more with IgE-stripped basophils. Considerable variation in the degree of response to HRA+ sera in the basophils of different normal subjects did not correlate with the degree of response of these cells to heterologous anti-IgE antiserum. Serum HRA levels were generally much lower when symptoms decreased in these patients with CIU. CONCLUSION: Serum HRA from patients with CIU appears to bind most commonly to the IgE receptor and may be a marker of clinical disease activity. HRA appears in an IgG-containing fraction of the serum and may contain IgE in some cases.

Comparison of serum histamine-releasing activity and clinical manifestations in chronic idiopathic urticaria.

We found increased serum histamine-releasing activity (HRA) in 27% of patients with chronic idiopathic urticaria. Patterns of clinical manifestations were similar in those with and without serum HRA, including responses to a standard treatment regimen. In HRA+ patients the degree of serum HRA generally correlated with clinical disease activity.

Products of arachidonic acid metabolism and the effects of cyclooxygenase inhibition on ongoing cutaneous allergic reactions in human beings.

BACKGROUND: There have been conflicting reports about the effects of inhibition of arachidonic acid metabolism on early- and late-phase cutaneous reactions. We re-examined this question with a unique nonsteroidal antiinflammatory drug, tenidap sodium. Tenidap sodium has been demonstrated in in vitro studies to inhibit cyclooxygenase, lipoxygenase, and cytokine production (interleukin-1, interleukin-6, tumor necrosis factor-alpha). METHODS: In a double-blind, randomized, crossover study, seven pollen-sensitive subjects ingested tenidap (120 mg, by mouth, daily) and placebo for 9 days with a 3-week washout period between treatments. On the eighth day they underwent allergen skin testing, measurable for up to 12 hours, and on the ninth day they underwent 5-hour skin chamber exposures to allergen and buffer. Chamber fluids were analyzed for cellular content, neutrophil granule protein release, cyclooxygenase and lipoxygenase arachidonic acid metabolites, histamine, and tryptase. RESULTS: Tenidap did significantly inhibit cyclooxygenase metabolites at both antigen and buffer sites but had no effect on histamine, tryptase, lipoxygenase metabolites, or granulocyte infiltration. Neutrophil granule release of lactoferrin was lower at the antigen site during tenidap administration, but there was no reduction of elastase release. Prostaglandin E2 and leukotriene E4 increased significantly at antigen sites compared with buffer sites during placebo administration and were the most prominent arachidonic acid metabolites detected. CONCLUSION: Tenidap, despite inhibiting cyclooxygenase release at antigen sites, had no effect on skin test responses to antigen or on antigen-induced mediator release or granulocyte infiltration. We conclude that cyclooxygenase metabolites are not important in the development of an allergic cutaneous inflammatory response.

Serum tryptase in idiopathic anaphylaxis: a case report and review of the literature.

Anaphylaxis is a life-threatening disease that characteristically presents with multiple arrays of dermatologic, respiratory, cardiovascular, and gastrointestinal derangements, in general, suddenly after exposure to an allergen. It can, however, occur without an identifiable precipitant or event, and this well-defined entity has been called idiopathic anaphylaxis. The diagnosis of idiopathic anaphylaxis is made after an appropriate allergic evaluation and exclusion of a provocative trigger. We report an unusual case of manifesting with gastroenteritis, urticaria, hypotension, and syncope. Measurement of serum tryptase, a mast cell enzyme, was used to substantiate the diagnosis. Tryptase level is a useful test that can be used to help diagnose this potentially fatal disease.

Polyautoimmune syndrome in common variable immunodeficiency.

Common variable immunodeficiency (CVI) is a heterogenous disorder with hypogammaglobulinaemia and multiple bacterial infections primarily involving the sinopulmonary tract. CVI patients have been known to have an increased tendency to develop autoimmune manifestations. Commonly associated autoimmune diseases include immune thrombocytopenic purpura, autoimmune haemolytic anaemia, and rheumatoid arthritis. In this paper we report a case of CVI presenting with multiple unusual autoimmune diseases including parotitis, vitiligo, atrophic gastritis, pernicious anaemia, and primary biliary cirrhosis. To our knowledge, this is the first case of CVI with polyautoimmunity and antimitochondria antibody. Recognition of this association is important because early diagnosis and treatment can greatly influence the prognosis.

The effects of gender on allergen-induced histamine release in ongoing allergic cutaneous reactions.

BACKGROUND: Marked variability in the amount of histamine released in the first hour of ongoing cutaneous reactions has been noted. This variability occurs even among subjects with similar degrees of skin test reactivity to antigen. METHODS: To determine gender effects on mediator release, we retrospectively compared: (1) skin chamber histamine release after a 0 to 1-hour and 1 to 5-hour exposure to antigen; (2) neutrophil accumulation after 5 hours of antigen exposure and skin test reactivity to antigen, histamine, and codeine in 91 male and 60 female subjects. RESULTS: There was no difference in skin test reactivity to antigen, histamine, or codeine between male and female subjects. However, in the group as a whole, male subjects released higher amounts of histamine in the first hour (74 +/- 4 ng/ml) than female subjects (55 +/- 4 ng/ml), (p < 0.01). When subjects were matched for equivalent skin reactivity to antigen, male subjects who were sensitive to 10 PNU/ml and 1 PNU/ml released more histamine (67 +/- 9 ng/ml and 82 +/- 9 ng/ml) than female subjects (51 +/- 7 ng/ml and 55 +/- 7 ng/ml) (p < 0.05 and < 0.01). In the most sensitive subjects, those with skin sensitivity to 0.01 PNU/ml of antigen, there was not a significant difference between the histamine release in the first hour in male (79 +/- 12 ng/ml) or female (69 +/- 9 ng/ml) subjects. No difference was observed between male and female subjects in either neutrophil or histamine accumulation in the 1- to 5-hour period. CONCLUSIONS: Since the first hour release of histamine is secondary to mast cell activation and the 1- to 5-hour histamine release is secondary to basophil activation, we conclude that the gender of the subject influences the degree of in vivo antigen-induced histamine release from mast cells.

Fibrin formation during ongoing cutaneous allergic reactions: comparison of responses to antigen and codeine.

BACKGROUND: Fibrin formation, assessed by fibrinopeptide A levels, was evaluated over a 5-hour period at skin chamber sites challenged continuously with pollen antigen or codeine in 10 reactive individuals. METHODS: The levels of fibrinopeptide A at antigen sites were compared with those at sites challenged with buffer diluent alone or with codeine for the first 3 hours, followed by antigen challenge during the subsequent 2 hours. RESULTS: Findings showed: (1) fibrinopeptide A levels were higher at antigen challenge sites than at codeine challenge sites by the third hour, with these levels at both sites greater than those at buffer sites; (2) antigen challenge of the previous codeine sites during the third to fifth hours led to a further increase in fibrinopeptide A levels; (3) fibrinopeptide A levels correlated with chamber fluid immunoglobulin G levels but not with chamber fluid histamine levels. CONCLUSIONS: Because antigen and codeine both activate mast cells prominently, these findings suggest that other factors play a role in the persistent fibrin formation at allergic skin reaction sites. Because antigen activates both basophils and mast cells and codeine only activates mast cells, we conclude that both basophils and mast cells contribute to the persistent fibrin formation at sites of allergic reactions.

Effects of skin-chamber fluids from human allergic reactions on neutrophil activation.

We have found activated neutrophils (PMNs) in skin chambers overlying the site of ongoing human allergic reactions. To determine whether this activation is due to component(s) released early in these IgE-mediated reactions, we investigated the in vitro effects of skin chamber fluids (CF) on resting blood PMNs. These skin CF had been previously obtained, at different time periods, at pollen-antigen-challenged or buffer-control-challenged sites in sensitive human subjects. PMNs incubated with CF obtained during the first hour of antigen challenge (first-hour CF) generated significantly more superoxide (O2-) than spontaneous production (p less than 0.001) and more than PMNs incubated with first-hour buffer-site CF (p less than 0.002). A pattern similar to O2- generation was observed in lactoferrin secretion during the incubation of the three cell aliquots described above (p less than 0.001). After these incubations, the subsequent responsiveness of the PMNs present in the cell buttons to opsonized zymosan, a PMN activator, was assessed. PMNs previously incubated with first-hour CF generated significantly more net O2- in response to opsonized zymosan than did PMNs previously incubated with first-hour buffer-site CF (p less than 0.001) or buffered saline (p less than 0.001). Again, a similar difference in the patterns of net lactoferrin secretion was observed (p less than 0.02). These events were not associated with PMN damage. Analogous studies with CF previously obtained during the second- to first-hour of antigen or buffer challenge stimulated much less than first-hour CF. We conclude that one or more components released early in IgE-mediated skin reactions can activate PMNs. The nature of the activating component(s) is unknown, with no evidence of activation by histamine, antigen, or other components found to date in first-hour CF.

Activation of the coagulation pathway during ongoing allergic cutaneous reactions in humans.

The levels of histamine, fibrinopeptide A (FPA), and IgG were determined in chamber fluids overlying sites of antigen versus buffer incubation for up to 7 hours in seven atopic and four antigen-nonreactive subjects. Significant increases in histamine were observed at antigen versus buffer sites in the atopic subjects throughout the 7-hour period. FPA and IgG levels were higher in antigen than in buffer sites from 0 to 5 hours in the atopic subjects. Furthermore, FPA levels correlated with the magnitude of induration at 6 hours after antigen injection in atopic subjects. There were no differences in the levels of histamine, FPA, or IgG at antigen versus buffer sites in the skin test-negative subjects. We suggest that the combination of vascular leakage of proteins, induced by vasoactive mediator release, and activation of these proteins during ongoing cutaneous reactions is responsible for fibrin formation that contributes to the pathophysiology of late-phase allergic responses in the skin.

Release of eosinophil granule proteins during IgE-mediated allergic skin reactions.

To determine whether the eosinophil (EOS), a prominent component of human allergic skin reactions, releases its potentially pathogenic components in vivo, we appended collection chambers to the bases of unroofed skin blisters and challenged the sites for varying time periods with either pollen antigen (Ag) or buffer (B)-control solutions. In seven sensitive subjects, continuous challenge with pollen Ag consistently induced release of more major basic protein (MBP) and eosinophil-derived neutrophil (EDN) than did B solution. Low levels of both MBP and EDN were observed during the first hour with increased accumulation during the second to fifth hour. Comparison of Ag- versus B-challenged site responses in individual subjects demonstrated significantly higher levels of both MBP and EDN at Ag than at B sites during the second to fifth hour. Levels of both MBP and EDN in the second to fifth hour correlated significantly with histamine release in the same sites in the first hour (r = 0.66 and 0.83, respectively). Imprints of the skin bases of the chambers after 5 hours demonstrated variable numbers of EOS at the Ag-challenged sites and only occasional EOS at the B-challenged sites; most cells on the skin bases were neutrophils. However, immunofluorescence localization of MBP in biopsy specimens of the blister bases revealed striking extra cellular MBP deposition. These findings indicate that EOS components accumulate in vivo in IgE-mediated human skin reactions, even when prominent EOS accumulation is not visualized, possibly because the EOS are degranulated in the allergic-reaction site. Release of EOS components in these reactions may be linked to earlier mast cell activation.(ABSTRACT TRUNCATED AT 250 WORDS)

Platelet-activating factor- and leukotriene B4-induced release of lactoferrin from blood neutrophils of atopic and nonatopic individuals.

We found increased accumulation of neutrophils and their components, lactoferrin (Lf) and elastase, as well as platelet-activating factor (PAF) and leukotriene B4 (LTB4) at sites of ongoing human allergic reactions. To determine whether PAF or LTB4, could be the stimulus for in vivo Lf release, blood neutrophils of 17 subjects were incubated with PAF, LTB4, or the phorbol ester, phorbol myristate acetate (PMA), and the released Lf (ELISA assay) was compared with spontaneous release. Significantly increased Lf release was induced by PAF, 10(-5) to 10(-8) mol/L (p less than 0.002); LTB4, 10(-7) to 10(-8) mol/L (p less than 0.004); and PMA (0.05 micrograms/ml) in a dose-dependent reaction. Cytochalasin was not required for Lf secretion but did enhance such responses. PAF-induced Lf secretion was inhibited by the specific PAF antagonist, BN 52063. More Lf was released from neutrophils of atopic than from nonatopic subjects in response to PAF, 10(-6) mol/L (4.2 micrograms/ml +/- 0.2 versus 2.6 micrograms/ml +/- 0.2; p less than 0.001) but not to LTB4, PMA, or buffer (p, not significant). We conclude that (1) PAF and LTB4 released in vivo could stimulate local neutrophils to release Lf with possible pathogenic effects and (2) neutrophils of atopic subjects are more responsive to PAF than neutrophils of nonatopic subjects in this regard.

In vivo antigen-induced cutaneous mediator release: simultaneous comparisons of histamine, tryptase, and prostaglandin D2 release and the effect of oral corticosteroid administration.

To determine if basophils were responsible for the persistent release of histamine during continuous antigen (Ag) administration in the skin, we compared the release of histamine, tryptase, and prostaglandin D2 (PGD2) at sites of continuous (5 hours) and intermittent Ag and codeine skin-chamber challenge in the skin of 16 atopic and four nonatopic subjects. In addition, we compared the release of these three mediators at sites of continuous Ag challenge in five subjects during oral administration of 1 mg/kg of methylprednisolone. Continuous Ag challenge induced an initial (first hour) peak of histamine release followed by a lower level plateau of histamine release during the next 4 hours. The level of histamine release during the second to fifth hours was significantly higher at these sites of continuous Ag challenge than at the codeine- or intermittent Ag-challenge sites. Levels of both tryptase and PGD2 were increased after the first hour of Ag or codeine challenge, and tryptase decreased progressively thereafter at all sites. In corticosteroid-treated subjects, the persistent histamine release during the second to fifth hours of Ag challenge was significantly reduced. In contrast, corticosteroid therapy did not affect histamine release during the first hour of Ag challenge nor the release of PGD2 or tryptase at any time period. These findings suggest that basophils are the source of the persistent histamine release at sites of continuous in vivo Ag challenge, since such release (1) was unaccompanied by release of tryptase or PGD2 (released from mast cells but not basophils), (2) did not occur after codeine challenge that activates mast cells but not basophils, and (3) was inhibited by steroids that inhibit the accumulation and release of histamine from basophils but not mast cells.

Determinants of in vivo histamine release in cutaneous allergic reactions in humans.

To determine host factors influencing the magnitude of mediator release during ongoing cutaneous allergic reactions in humans, we compared, in 22 subjects, the first-hour, second- to fifth-hour, and total (0 to 5 hours) skin chamber histamine release to (1) the in vitro reactivity and sensitivity of basophils to antigen for histamine release and (2) skin test sensitivity and reactivity to antigen, histamine, and codeine. There was no significant correlation between the first-hour and second- to fifth-hour histamine release. With a combination of basophil, antigen, histamine, and codeine skin sensitivity and reactivity, 64% to 75% of the magnitude of the first-hour, second- to fifth-hour, and total (0 to 5 hours) skin chamber histamine release could be accounted for. We conclude that antigen-induced in vivo allergic responses are a complex phenomenon dependent, in part, on antigen sensitivity, basophil and mast cell reactivity, and end organ responsiveness to mediators.

Skin reactivity to codeine and histamine during prolonged corticosteroid therapy.

Corticosteroids, used in low to moderate doses for short time intervals, do not suppress immediate percutaneous skin test responses to allergens, compound 48/80, or histamine. During routine skin testing, in our clinic, intradermal injection of codeine (1 mg/ml) and histamine (0.02 mg/ml) are used as positive controls. We had noted that responses to codeine but not histamine are decreased in some patients with asthma who had been receiving prolonged corticosteroid therapy. Therefore, we retrospectively compared skin test responses to codeine and histamine between 25 adult subjects with asthma receiving steroids (group I) and 25 age-matched control subjects (group II). In group I, the mean wheal diameters, induced by codeine but not histamine, were significantly less than diameters in group II. This decreased skin test reactivity to codeine was not due to effects of theophylline also taken by group I subjects, since the skin test reactions of other subjects with asthma, treated with theophylline but not steroids (group III), were not significantly different from reactions in group II. We conclude that prolonged courses of corticosteroids do not appear to alter histamine-induced vascular reactivity in skin but may affect cutaneous mast cell responses by an undefined mechanism.