Human Skin Reactions Research Articles

530 T lymphocyte subsets in human late-phase skin reactions

530 T lymphocyte subsets in human late-phase skin reactions

Effects of Topical Corticosteroid Therapy on Immune Reactions in Human Skin

Effects of Topical Corticosteroid Therapy on Immune Reactions in Human Skin

Increased expression of CR3 (C3bi receptor) on neutrophils in human inflammatory skin reactions.

To help determine whether the neutrophils (PMN) found in skin inflammatory reactions are activated, we have compared the expression of the C3bi receptor (CR3) on such cells with that on autologous blood PMN in 10 pollen-sensitive subjects. Using skin chambers overlying denuded blister bases we collected PMN at 2 or 4 hr at sites of challenge with pollen antigen or buffer solution. These cells and PMN in autologous blood were incubated with monoclonal anti-CR3 antibody and the expression of CR3 was measured by indirect fluorescence and flow cytometry. Significantly more PMN were found at antigen than at buffer sites at 2 hr (7.02 +/- 0.45 X 10(5) vs 0.71 +/- 0.25 X 10(5] and at 4 hr (2.2 +/- 0.57 X 10(6) vs 5.47 X 10(5). The mean CR3 expressions on PMN at antigen and buffer sites were similar (117 +/- 7.4 vs 118 +/- 9.0); both were significantly greater than on blood PMN (17.6 +/- 1.5; P less than 0.005). PMN from both sites could be stimulated further in vitro with formyl-methionyl-leucyl-phenylalanine (FMLP) to express more CR3 to a level even greater than in FMLP-stimulated blood PMN (155 +/- 11 and 157 +/- 12, respectively, vs 108 +/- 7 in blood PMN). The incubation of blood PMN with the noncellular component of the chamber fluid led to a moderate (28-100%) increase in CR3 expression, but far less than the CR3 expression on the chamber fluid PMN themselves. Since surface CR3 is thought to be an activation marker important in PMN adhesion, these findings may be important in understanding the emigration of PMN in skin inflammatory reactions.

The effect of nedocromil on weal reactions in human skin.

1. Nedocromil 2% iontophoresed into human skin had no effect on wealing produced by intradermal histamine, 48/80 or house dust mite antigen. 2. Iontophoresis of 0.002-2% nedocromil itself resulted in dose-related wealing. 3. This wealing was reduced by 62 +/- 8% s.e. mean by the H1-receptor antagonist terfenadine which decreased histamine wealing by 68 +/- 2% s.e. mean. 4. Nedocromil may therefore act as a weak agonist on a skin mast cell receptor concerned with histamine release.

Neutrophil activation in human inflammatory skin reactions

To determine the functional activity of neutrophils emigrating to the sites of ongoing human allergic inflammatory reactions, we assessed the intensity of their intracellular oxidative metabolism by measuring the intracellular oxidation by H2O2 of the dye, 2',7'-dichlorofluorescein diacetate (DCFH-DA), to fluorescent 2',7'-dichlorofluorescein. The intensity of intracellular fluorescence was measured by flow cytometry. In 13 atopic subjects, two denuded skin blister bases were challenged for 5 hours with pollen antigen and two blister bases with buffer. Both the level of histamine and mean number of cells recovered at antigen sites were greater than at buffer sites. Oxidation of DCFH-DA by neutrophils recovered from both antigen and buffer sites was significantly greater than that of autologous peripheral blood neutrophils (PBNs), reflecting an increase in the spontaneous generation H2O2 of cells recovered from the sites of inflammation. DCFH-DA oxidation by cells recovered from sites of antigen incubation was significantly greater than cells from buffer site incubations. Neutrophils from both antigen and buffer sites could be stimulated further in vitro by phorbol myristate acetate to the same level of H2O2 generation as phorbol myristate acetate-stimulated PBNs. In five subjects studied, the noncellular component of chamber fluids collected at 1 and 5 hours stimulated PBNs to increase their oxidative metabolism by 42% to 62%; however, this increased level of intracellular H2O2 was still much less than the spontaneous H2O2 generation observed in cells recovered from sites of allergic inflammation. The increased oxidative metabolism of neutrophils in human allergic and inflammatory skin reactions has important pathophysiologic implications for the role of these cells in inflammatory responses.

Ultraviolet B Irradiation Induces Changes in the Distribution and Release of Arachidonic Acid, Dihomo-γ-linolenic Acid, and Eicosapentacnoic Acid in Human Keratinocytes in Culture

There is increasing evidence that derivatives of 20-carbon polyunsaturated fatty acids, the eicosanoids, play an important role in the inflammatory responses of the human skin. To better understand the metabolic fate of fatty acids in the skin, the effect of ultraviolet B (UVB) irradiation (280-320 nm) on the distribution and release of 14C-labeled arachidonic acid, dihomo-gamma-linolenic acid, and eicosapentaenoic acid in human keratinocytes in culture was investigated. Ultraviolet B irradiation induced the release of all three 14C-labeled fatty acids from the phospholipids, especially from phosphatidylethanolamine, and this was accompanied by increased labeling of the nonphosphorus lipids. This finding suggests that UVB induces a significant liberation of eicosanoid precursor fatty acids from cellular phospholipids, but the liberated fatty acids are largely reincorporated into the nonphosphorus lipids. In conclusion, the present study suggests that not only arachidonic acid but also dihomo-gamma-linolenic acid, and eicosapentaenoic acid might be involved in the UVB irradiation-induced inflammatory reactions of human skin.

Dynamic changes in the epidermal OKT6 positive cells at mild irritant reactions in human skin

In the present study we induced mild irritant contact reactions by using 0.5% sodium lauryl sulphate (SLS) in distilled water or with distilled water in patch tests for 6 or 24 hours. The biopsies were taken at 6, 24, 48 and 96 hours. Light and electron microscopy were used to assess the irritant reactions produced and the monoclonal antibody OKT6 was used for the detection of the LCs. The number of the epidermal OKT6 positive dendritic cells was found to be increased at 48 and 96 hours after the exposure to SLS and at 96 hours in the water patch tests. It is concluded that mild irritant stimuli cause an increase in the LCs (OKT6 positive cells) and thus might influence and modulate the response to subsequent exposures to allergens.

Some effects of calcitonin gene-related peptide in human skin and on histamine release

Calcitonin gene-related peptide (CGRP) produced a dose-related wheal and flare reaction in human skin at doses of 12.5 to 50 pmol. The flare response but not the wheal response to CGRP and substance P were inhibited by prior treatment of the subject with oral chlorpheniramine, 16 mg. CGRP, but not substance P, was potent in producing a delayed erythema and surrounding pallor in human skin, which peaked at 1 h and persisted for more than 3 h after injection, when wheal and flare responses had subsided. The delayed response was accompanied by infiltration of polymorphonuclear leukocytes. The delayed erythema and pallor produced in response to CGRP were not inhibited by oral chlorpheniramine, or by 4% prilocaine injected locally. CGRP released histamine from rat peritoneal mast cells over the concentration range 2.5-10 microM. CGRP was about fourfold less potent than substance P in releasing histamine. The substance P analogue, [D-Pro4, D-Trp7,9,10]SP4-11 10 microM, and benzalkonium chloride 10 microM inhibited histamine release from rat mast cells stimulated by either CGRP or substance P.

The effect of ranitidine, alone and in combination with clemastine, on allergen-induced cutaneous wheal-and-flare reactions in human skin

The effect of intradermal ranitidine (administered alone and in combination with clemastine) on allergen-mediated wheal-and-flare reactions has been evaluated in a double-blind study on 10 healthy atopic volunteers. Ranitidine alone, administered in doses over a 10 4-fold concentration range, had no effect on the size either of allergen-induced wheal or flare reactions. Clemastine alone evoked a dose-related inhibition of both wheal and flare. Compared to the inhibition achieved by clemastine alone, the combination of ranitidine with clemastine produced a small but significant increase in inhibition of allergen-induced flare at ranitidine concentrations of 10 −5 mol/L ( p < 0.001) and 10 −6 mol/L ( p < 0.01), and of allergen-induced wheal at ranitidine concentration 10 −5 mol/L ( p < 0.01). Our results provide further evidence for the presence of cutaneous histamine H 2 receptors and their participation in the formation of allergen-mediated skin reactions but indicate that the contribution of cutaneous histamine H 2-receptor stimulation to the production of immediate wheal-and-flare reactions evoked by allergen is only modest.

The influence of ranitidine, alone and in combination with clemastine, on histamine-mediated cutaneous weal and flare reactions in human skin.

Significant, (P less than 0.05) inhibition of histamine induced cutaneous weal and flare reactions by ranitidine at 10(-5) M concentration has been demonstrated in a double blind, in vivo study; the results support the evidence for cutaneous H2-histamine receptors provided by previous studies using cimetidine and metiamide. The degree of inhibition of histamine mediated cutaneous reactions achieved by clemastine was increased by the administration of clemastine and ranitidine together, for ranitidine concentrations 10(-5) M (P less than 0.001) and 10(-6) M (P less than 0.05). The magnitude of the inhibitory effect of ranitidine, both administered alone and in combination with clemastine, suggests that in the production of histamine induced cutaneous weal and flare reactions, the contribution afforded by stimulation of cutaneous H2-histamine receptors is only small.

The evaluation of an RBE for iodine 125 relative to iridium 192 from a human erythematous skin reaction using a new approach to skin scoring

125I seeds are playing an ever increasing role in brachytherapy (Sealy et al, 1980; Goffinet et al, 1981) and such treatments necessitate the evaluation of an RBE for the conditions under which the iodine seeds are used for treatment (Hering, 1980). Several attempts at such an evaluation have already been made (Hering et al, 1978; Hering, 1980) using the root meristem of the broad bean, Vicia faba, as the biological test system, and an RBE of 1.5 was obtained using 192Ir as the reference radiation. This value was also used in the dose evaluations for the treatments of patients at this hospital (Sealy et al, 1980) as it agrees with predictions by Kim and Hilaris (1975) and Zeitz et al (1977). Nevertheless experimental verification on mammalian systems is considered essential. Whilst we were studying B16 melanoma cells, an opportunity arose for studying acute single erythematous doses on human skin. A similar approach using skin pigmentation after irradiation has been used previously in elucidating similar ...

Wheal reactions in human skin after injection of leukotrienes B 4, C 4, D 4 and E 4

Intradermal injections of 1–50 pmol leukotriene B 4, C 4, D 4 and E 4, (LTB 4, LTC 4, LTD 4 and LTE 4) were performed in healthy subjects and patients with recurrent urticaria. A wheal and erythema were seen 15 minutes after injection and were most marked after LTC 4 and LTD 4. LTE 4 also produced a wheal whereas the reaction to LTB 4 did not significantly differ from the saline control. When mixed with histamine no potentiation of the wheals was noted and no significant difference in reaction was observed between the healthy controls and those with urticaria.

The active site of human C4a anaphylatoxin

The human C4 activation peptide C4a has recently been shown to be biologically active and to share common tissue receptors with human C3a anaphylatoxin. Human C3a and C4a each induce contraction and cause cross-desensitization of isolated guinea-pig ileal strips. The essential active site of C3a is comprised in the model peptide containing the five COOH-terminal residues. Leu-Gly -Leu Ala-Arg. The anaphylatoxic activities of the corresponding C4a pentapeptide. Ala -Gly-Leu- Gln -Arg, and several other synthetic peptides related to the COOH-terminal sequence of human C4a were examined. The C4a pentapeptide induced contraction of guinea-pig ileum at 1 × 10 −3 M and produced a wheal and flare reaction in human or guinea-pig skin when 2–5 μmole were injected intradermally. The corresponding C3a pentapeptide is 500-fold more active, since it induces contraction of guinea-pig ileum at 3–4 × 10 −6 M and only 4–10 nmole induce a visible skin reaction. Although the C4a pentapeptide is relatively inactive compared to the C3a pentapeptide, two analogs of these peptides. Leu-Gly Leu- Gln -Arg and Ala -Gly -Leu-Ala-Arg, each exhibited significantly greater activity than Ala -Gly-Leu- Gln -Arg and each analog desensitized ileal smooth muscle towards contraction by either C3a or C4a. Thus it is a combination of two amino acid substitutions, the Ala for Leu-73 and Gln for Ala-76, in the COOH-terminal pentapeptide of C3a that accounts for the markedly reduced activity of C4a. The contribution of the COOH-terminal portion of C4a on its activity was further documented by examining the C4a octapeptide. Lys-Gly-Gln-Ala-Gly-Leu-Gln-Arg and a trialanyl analog. Ala - Ala - Ala - Ala -Gly-Leu-Gln-Arg. The C4a octapeptide, C4a (70–77), exhibited 5-fold greater biologic activity than the C4a pentapeptide, while the trialanyl analog was 40-fold more active. Anaphylatoxic activities of the C4a-(73–77) pentapeptide. C4a-(70–77) octapeptide, and the trialanyl octapeptide analog and their ability to specificially block the action of C3a and C4a on smooth muscle tissue support the conclusion that, as in C3a, the essential active site of C4a resides at its COOH terminus. Since C4a functions as an anaphylatoxin and significant quantities of this mediator may be generated in individuals with hereditary angioneurotic edema (HANE), the hypotheses that the kinin-like activity promoting edema in HANE patients is derived solely from component C2 and/or kininogens should be reappraised. The activities previously assigned to C4a and now confirmed by synthetic C4a analog peptides suggest that the kinin-like activity generated in HANE plasma may be derived in part from C4a.

The biologic activity of mast cell granules. VI. The effect of vinblastine-induced neutropenia on rat cutaneous late phase reactions.

Type I immediate hypersensitivity reactions in human and rat skin may be followed by late phase reactions (LPR). A consistent feature of both human and rat LPR is the early histologic appearance of neutrophils, which, in rats, is followed by the later appearance (8 to 24 hr) of mononuclear cells. To determine the importance of the neutrophil in the development of LPR, rats were depleted of neutrophils using parenteral injections of vinblastine sulfate (VS). VS produced a dose-dependent neutropenia, with the maximal effect on day 4. LPR that were induced with anti-IgE, isolated mast cell granules (MCG), or purified high (greater than 10,000 daltons) and low (500 to 10,000 daltons) m.w. fractions obtained from MCG were significantly abrogated in VS-treated rats. In neutropenic rats previously immunized with complete Freund's adjuvant, the intensity of inflammatory reactions produced by skin testing with purified protein derivatives was also significantly reduced. Administration of exogenous neutrophils to neutropenic animals partially reconstituted the reduced LPR. These data confirm and extend previous observations on the contribution of neutrophils to delayed hypersensitivity reactions and provide evidence that the neutrophil is critical for the development of rat cutaneous LPR as well.

IgE-mediated release of histamine from human cutaneous mast cells.

We investigated the ability of antigen-IgE interactions to stimulate histamine release from human infant cutaneous mast cells. Skin obtained at circumcision contained numerous perivascular mast cells, as assessed by light and electron microscopy. The histamine content of this tissue averaged 17.7 ng (+/- 1.5 SEM)/mg wet weight. Challenge of 200-microns thick sections of unsensitized skin with varying concentrations of monoclonal murine antibodies to human IgE caused no net release of histamine. After skin sections were incubated in the presence of 5 micrograms/ml of human myeloma IgE (S) for 120 min at 37 degrees C, monoclonal anti-IgE challenge resulted in 40.1% (+/- 6.0 SEM) histamine release. Similar passive sensitization with 1/20 dilutions of serum from humans expressing IgE to purified Juniperus sabinoides (JS) antigen rendered the tissue responsive to specific antigen challenge. Dose-related histamine release occurred over 30 min with optimal release of 12.6% (+/- 2.4 SEM) after stimulation with 100 ng/ml of JS antigen. This reaction required sensitization with serum containing IgE to JS and was antigen-specific. Optimal reactions to antigen occurred at 3 mM added Ca++, 34 degrees C to 37 degrees C, pH 7.2. Antigen-induced release was markedly influenced by the added Ca++ concentration; no release occurred in the absence of Ca++, 54% of the optimal response was observed at 2 mM Ca++, and 28% of the optimal response occurred at 4 mM Ca++. The addition of Mg++ did not influence antigen-induced release. The results of this study provide functional evidence that 1) human infant cutaneous mast cells express Fc-epsilon receptors; 2) these receptors are largely unoccupied in vivo; and 3) stimulation of passively sensitized infant mast cells with anti-IgE or specific antigen leads to immediate histamine release. This new system should permit detailed in vitro studies of immediate hypersensitivity reactions in human skin.

Structure-activity relationships for some substance P-related peptides that cause wheal and flare reactions in human skin.

Substance P (6.25-25 p-mole) produced dose-dependent flare and wheal responses when injected intradermally into the volar surface of the human forearm. The maximum flare response was obtained within the first 3 min of injection and declined thereafter. The wheal response reached a maximum after 12 min following the injection. Only those peptides having one or more basic residues in the N-terminal region were effective in producing a flare reaction. Eledoisin-related peptide and SP1-9 were 17 and 7 times less active than substance P respectively, whilst [D-pro2, D-phe7, D-trp9]SP1-11 was twice as active. The N-terminal tetrapeptide, SP1-4 and eledoisin were inactive in the dose range tested. Wheal-producing activity was not dependent on the presence of basic residues and the rank order of relative potencies was: physalaemin (2.0): [D-pro2, D-phe7, D-trp9]SP1-11 (1.1): SP1-11 (1.0): SP4-11 (0.4): SP1-9 (0.15): eledoisin-related peptide (0.08): eledoisin (0.06). The N-terminal tetrapeptide failed to produce a wheal response in the dose range tested. Substance P was approximately equi-active with poly-L-arginine in the production of wheal and flare and both of these agents were about 10 times more potent than histamine. Adenosine triphosphate (25-400 n-mole) produced dose-dependent wheal and flare responses and was 10,000 times less potent than substance P. Pre-treatment of the subjects with the H1 histamine antagonist, chlorpheniramine, (20 mg I.V.) reduced the wheal and flare responses to substance P. Local anaesthetic injection into the skin reduced the spread of the flare response but did not affect the development of the wheal response. Pre-treatment of the skin with capsaicin reduced the flare but not the wheal response to intradermal injection of histamine. The results are discussed in relation to the mechanism of the 'axon reflex' vasodilatation in skin. This is thought to involve mast cells in addition to substance P-containing primary afferent neurones.

The mechanisms of histamine release in cutaneous type 1 allergy and enzymic histamine metabolism in skin

The mechanisms of type 1 allergy in human skin were studied using an in vitro experimental model. The antigen-induced histamine release reaction was temperature- and Ca++ -dependent. Diisopropylfluorophosphate inhibited the histamine release suggesting that the activation of serine esterase in the mast cells in human skin may be essential to the histamine release reaction. That the histamine release was inhibited by cytochalasin B and colchicine indicated that microfilaments and microtubules may have a role in the histamine release reaction in human skin. The inhibition of the histamine release by catecholamines and methylxanthines which increase the cellular concentration of cyclic AMP suggested that cyclic AMP may regulate the antigen-induced histamine release from the mast cells in human skin.

Sunscreens: Topical and systemic approaches for protection of human skin against harmful effects of solar radiation

This review deals with topical and systemic approaches for protection of human skin against the harmful effects of solar radiation. Two concerns about the deleterious effects of sun exposure involve: (1) acute effects (e.g., sunburn and drug-induced phototoxicity) and (2) potential long-term risks of repeated sun exposures leading to development of solar elastosis, keratoses, induction of both nonmelanoma and melanoma skin cancer, and alteration of immune responses and functions. Action spectra of normal and abnormal reactions of human skin to acute and chronic effects of solar radiation are presented with a view to helping the physician prescribe the appropriate sunscreens. Factors that influence acute effects of sunburn are reviewed. Various artificial methods effective in minimizing or preventing harmful effects of solar radiation, both in normal individuals and in patients with photosensitivity-related problems, are discussed. Emphasis is placed on the commercially available chemical sunscreens and their properties. Sun protection factor (SPF) values of several brand-name formulations determined with a solar simulator under indoor conditions (laboratory) and with solar radiation under natural, field conditions are presented. Factors responsible for variations of SPF values observed under indoor and outdoor conditions are reviewed. Systemic photoprotective agents and their limitations are outlined. The photobiology of melanin pigmentation (the tanning reaction) is briefly discussed, with emphasis on the dangers of using quick-tanning lotions for stimulation of the tanning reaction.

Final Report on the Safety Assessment of TEA-Lauryl Sulfate

TEA-Lauryl Sulfate is the triethanolamine salt of lauryl sulfuric acid. It is used in cosmetics as a detergent, a stabilizer and a solubilizer. The ingredient was moderately to slightly toxic in acute oral studies with rats; reported LD50s ranged from 0.27 to &gt; 1.95 g/kg. Animal studies showed that the surfactant is a significant skin and eye irritant. In clinical studies, shampoos containing 10.5% TEA-Lauryl Sulfate caused no irritation under semioccluded conditions. Diluted shampoos containing 0.15-7.5% of the surfactant caused human skin reactions ranging from no irritation to moderate irritation. This skin irritation phenomenon is observed with most detergents. Undiluted shampoos containing 10.5% TEA-Lauryl Sulfate showed low potential for eliciting human skin sensitization. No evidence of photosensitization was observed in subjects exposed to solutions containing up to 0.42% TEA-Lauryl Sulfate. On the basis of the available animal and human data, the Panel concludes that TEA-Lauryl Sulfate can be used without significant irritation at a final concentration not exceeding 10.5%. Greater concentrations may cause irritation, especially if allowed to contact the skin for significant periods of time.

A Microscopic Study of Inflammatory Reactions in Human Skin Induced by Histamine and Compound 48/80

The sequential changes induced by histamine and compound 48/80 in normal skin were studied by light and electron microscopy. Histamine (50 μ g) or compound 48/80 (10 μ g) was injected intradermally as a single bolus, a repeated bolus every 15mm for 2hr. or as a constant infusion (120 μ g histamine/hr; 24 μ g compound 48/80hr) for 4hr. Skin biopsies were taken 15mm to 24hr after injection and cellular and other morphological changes were assessed in 1 μ m Epon sections by light microscopy. Fifteen minutes after a single bolus of histamine there was dilatation of dermal vessels, endothelial swelling, fibrin deposition, perivascular edema and slight mast cell degranulation. At 4hr these edema-related changes had largely regressed. Perivascular leukocytes were usually absent. After repeated bolus injections or continuous infusions of histamine a slight infiltrate of neutrophils, cosinophils and mononuclear cells was seen around venules. After a single injection of compound 48/80 there was a perivascular infiltration of neutrophils and eosinophils that was slight to moderate at 15–30mm and greater at 24hr. Electron microscopy showed that many of these leukocytes had undergone degranulation or lysis even within vessel lumina. Exocytotic mast cell degranulation was more extensive with compound 48/80 than with histamine or with phosphate buffered saline. There was marked variation in both the number of mast cells undergoing degranulation and the degree of degranulation in individual cells. We conclude that the greater cellular reaction caused by compound 48/80 probably depends upon release from mast cells of mediators other than histamine. The contribution of fibrin in acute dermal inflammation needs to be examined further.