Immunoglobulin E-mediated Allergic Responses Research Articles

Potential Negative Effects of Antimicrobial Allergy Labelling on Patient Care: A Systematic Review

Antimicrobial allergy labels, either self-reported or placed in a patient's medical record, are common, but in many cases they are not associated with a true immunoglobulin E-mediated allergic response. To assess the impact of antimicrobial allergy labels on antimicrobial prescribing, resource utilization, and clinical outcomes. The MEDLINE, Embase, CINAHL, and Scopus electronic databases were searched for the period 1990 to January 2016. Controlled studies with the objective of assessing antimicrobial prescribing, resource utilization, and/or clinical outcomes associated with antimicrobial allergy labels were included. The search identified 560 unique citations, of which 7 articles met the inclusion criteria. One additional article identified by an expert in the field was also included. Four of the identified papers were limited to penicillin or other β-lactam allergies. Six studies noted differences in antibiotic selection between patients with allergy labels and those without such labels. Broader-spectrum or second-line agents (e.g., vancomycin, clindamycin, and fluoroquinolones) were more commonly prescribed for patients with penicillin allergy labels. Antibiotic therapy costs were significantly higher for patients with allergy labels than for those without. The impact of allergy labels on clinical outcomes was mixed. One study indicated a longer length of hospital stay, 2 studies reported higher readmission rates, and 1 study reported a higher rate of antibiotic-resistant organisms for patients with allergy labels. Most of the available literature is limited to penicillin or β-lactam allergy. The growing body of knowledge supports the concept that β-lactam allergy labels are not benign and that labelling in the absence of a true allergy has a negative effect on patient care. Allergy labelling appears to be associated with suboptimal antibiotic selection, greater treatment costs, prolonged length of stay, greater readmission rates, and higher prevalence of antibiotic-resistant organisms. There is an opportunity for antimicrobial stewardship programs to implement systematic allergy verification to optimize antimicrobial therapy and improve patient care.

Effects of ionizing radiation on differentiation of murine bone marrow cells into mast cells.

Mast cells, immune effector cells produced from bone marrow cells, play a major role in immunoglobulin E–mediated allergic responses. Ionizing radiation affects the functions of mast cells, which are involved in radiation-induced tissue damage. However, whether ionizing radiation affects the differential induction of mast cells is unknown. Here we investigated whether bone marrow cells of X-irradiated mice differentiated into mast cells. To induce mast cells, bone marrow cells from X-irradiated and unirradiated mice were cultured in the presence of cytokines required for mast cell induction. Although irradiation at 0.5 Gy and 2 Gy decreased the number of bone marrow cells 1 day post-irradiation, the cultured bone marrow cells of X-irradiated and unirradiated mice both expressed mast cell–related cell-surface antigens. However, the percentage of mast cells in the irradiated group was lower than in the unirradiated group. Similar decreases in the percentage of mast cells induced in the presence of X-irradiation were observed 10 days post irradiation, although the number of bone marrow cells in irradiated mice had recovered by this time. Analysis of mast cell function showed that degranulation of mast cells after immunoglobulin E–mediated allergen recognition was significantly higher in the X-irradiated group compared with in the unirradiated group. In conclusion, bone marrow cells of X-irradiated mice differentiated into mast cells, but ionizing radiation affected the differentiation efficiency and function of mast cells.

SG-HQ2 inhibits mast cell-mediated allergic inflammation through suppression of histamine release and pro-inflammatory cytokines.

In this study, we investigated the effect of 3,4,5-trihydroxy-N-(8-hydroxyquinolin-2-yl)benzamide) (SG-HQ2), a synthetic analogue of gallic acid (3,4,5-trihydroxybenzoic acid), on the mast cell-mediated allergic inflammation and the possible mechanism of action. Mast cells play major roles in immunoglobulin E-mediated allergic responses by the release of histamine, lipid-derived mediators, and pro-inflammatory cytokines. We previously reported the potential effects of gallic acid using allergic inflammation models. For incremental research, we synthesized the SG-HQ2 by the modification of functional groups from gallic acid. SG-HQ2 attenuated histamine release by the reduction of intracellular calcium in human mast cells and primary peritoneal mast cells. The inhibitory efficacy of SG-HQ2 was similar with gallic acid. Enhanced expression of pro-inflammatory cytokines such as tumor necrosis factor-α, interleukin-1β, interleukin-4, and interleukin-6 in activated mast cells was significantly diminished by SG-HQ2 100 times lower concentration of gallic acid. This inhibitory effect was mediated by the reduction of nuclear factor-κB. In animal models, SG-HQ2 inhibited compound 48/80-induced serum histamine release and immunoglobulin E-mediated local allergic reaction, passive cutaneous anaphylaxis. Our results indicate that SG-HQ2, an analogue of gallic acid, might be a possible therapeutic candidate for mast cell-mediated allergic inflammatory diseases through suppression of histamine release and pro-inflammatory cytokines.

Anti-Allergic Action of Aged Black Garlic Extract in RBL-2H3 Cells and Passive Cutaneous Anaphylaxis Reaction in Mice

Garlic (Allium sativum) has been used as a food as well as a component of traditional medicine. Aged black garlic (ABG) is known to have various bioactivities. However, the effect of ABG on allergic response is almost unknown. In the present study, we investigated whether ABG can inhibit immunoglobulin E-mediated allergic response in RBL-2H3 cells as well as in vivo passive cutaneous anaphylaxis (PCA). In in vitro tests, ethyl acetate extract (EBG) of ABG significantly inhibited the release of β-hexosaminidase (IC₅₀, 1.53 mg/mL) and TNF-α (IC₅₀, 0.98 mg/mL). Moreover, BG10, an active fraction of EBG, dramatically suppressed the release of β-hexosaminidase (IC₅₀, 53.60 μg/mL) and TNF-α (IC₅₀, 27.80 μg/mL). In addition, BG10 completely blocked the formation of prostaglandin E₂ and leukotriene B₄ at ≥25 μg/mL. When the effect of BG10 on FcɛRI receptor cascade was investigated, BG10 significantly inhibited the phosphorylation of Syk, but not Lyn. Furthermore, BG10 dose dependently decreased the phosphorylation of cytosolic phospholipase A₂ (cPLA₂) and 5-lipoxygenase (5-LO) as well as the expression of cyclooxygenase-2 (COX-2). Consistent with what has been mentioned earlier, BG10 also significantly inhibited the PCA reaction in mice. In conclusion, these results indicate that ABG suppresses the allergic response, and the mechanism for its anti-allergic action may involve suppressions of Syk, cPLA₂, 5-LO, and COX-2. The anti-allergic actions of ABG, EBG, or BG10 suggest that they may be useful as functional foods for allergic diseases.

Inhibitory Effect of Ellagitannin Metabolites on IgE-Mediated Allergic Responses in RBL-2H3 Cells

The effects of four ellagitannin metabolites (M1-M4) and ellagic acid on immunoglobulin E-mediated allergic responses in rat basophilic leukemia-2H3 cells were investigated. M1-M4 inhibited the antigen-induced degranulation and secretion of interleukin-4 and tumor necrosis factor-α, but ellagic acid only slightly did so under the same experimental conditions. M1 inhibited the activation of the mitogen-activated protein kinases in antigen-stimulated cells.

Ellagic Acid Attenuates Immunoglobulin E-Mediated Allergic Response in Mast Cells

Ellagic acid is known to have anti-oxidant, anti-carcinogenic and anti-mutagenic effects. However, roles of ellagic acid in the immediate-type allergic reactions have not yet been investigated. In the present study, we have demonstrated that ellagic acid attenuates immunoglobulin (Ig)E-mediated allergic response in mast cells and in vivo. Oral administration of ellagic acid inhibited anti-dinitrophenyl (DNP) IgE-mediated passive cutaneous anaphylaxis. Ellagic acid dose-dependently reduced histamine release and the expression and secretion of pro-inflammatory cytokines, such as tumor necrosis factor-alpha and interleukin-6 in rat peritoneal mast cells (RPMC) activated by anti-DNP IgE. Moreover, ellagic acid suppressed an increase in intracellular calcium ion concentration ([Ca(2+)](i)) in RPMC. Furthermore, ellagic acid decreased the activation of nuclear factor-kappa B (NF-kappaB). Decreased NF-kappaB activity as well as reduced [Ca(2+)](i) might be involved in the inhibitory effect of ellagic acid on the secretory response. Our findings provide possibility that ellagic acid may serve as an effective therapeutic agent for allergic diseases.

Case Report: Anaphylactic Reaction to Guaifenesin

Adverse drug reactions lead to a significant number of hospital admissions each year and thus contribute to the overall financial burden of health care. Some of these drug reactions are allergic responses. As the overall predictability of allergic responses to drugs remains low, efforts to improve our understanding of the processes underlying these responses continue as we strive toward the ultimate goal of primary prevention. Allergic reactions range from mild pruritic to severe systemic anaphylactic responses. We report a case of a young healthy man who developed an anaphylactic reaction to an over-the-counter expectorant. A skin test showed that the patient had an immunoglobulin E-mediated allergic response to guaifenesin, one of the components of commonly available cough medications. Our review of published literature showed that this is the first report of a severe allergic response to guaifenesin.

An RGS for PI3K

Immunoglobulin E (IgE) triggers the activation of the FcεRI immune receptor, which signals through immunoreceptor-based tyrosine activation motifs, in response to allergens. FcεRI activation on mast cells produces an increase in intracellular calcium concentration, which causes degranulation and the release of inflammatory mediators such as histamine. The signaling pathway from the FcεRI to calcium involves the tyrosine kinases Lyn and Syk, the adaptor proteins Gab2 and Grb2, phosphoinositide 3-kinase (PI3K), and phospholipase C-mediated production of inositol 1,4,5-trisphosphate (IP 3 ). G protein-coupled receptors, such as adenosine or prostaglandin receptors, may amplify IgE-mediated mast cell activation. Bansal et al . found that RGS13, a member of the R4 subfamily of regulator of G protein signaling (RGS) proteins, provided an inhibitory input into IgE-mediated mast cell degranulation through a mechanism involving the p85 subunit of PI3K instead of a G protein. RGS proteins are best known for attenuating G protein signaling through their actions as GTPase-activating proteins (GAPs) for specific Gα subunits and for interfering with the interactions between Gα subunits and downstream effectors. Bansal et al . studied bone marrow-derived mast cells (BMMCs) from Rgs13 knockout ( Rgs13 -KO) mice and found that antigen-elicited degranulation was greater and inhibition of G proteins with pertussis toxin did not alter this enhanced response, suggesting that G proteins were not mediating the effect. Furthermore, reconstitution of the Rgs13 -deficient BMMCs with mutant forms of RGS13 that could not interact with G proteins prevented the enhanced degranulation response. The Rgs13 -KO mice also exhibited elevated cutaneous allergic response compared with wild-type mice, yet did not show altered mast cell numbers or morphology. Using glutathione S -transferase fused to RGS13, the p85 subunit of PI3K was identified from lysates of BMMCs as a tyrosine-phosphorylated protein that interacted with RGS13. The interaction between RGS13 and p85 was direct and occurred with recombinant proteins, although it did require p85 tyrosine phosphorylation (achieved by incubation with Lyn). Rgs13 -deficient BMMCs showed increased production of IP 3 , phosphorylation of Akt, and increased intracellular calcium concentrations in response to antigen. Transduction of wild-type BMMCs with a cell-permeable RGS13 construct inhibited antigen-stimulated calcium flux and PI3K activity. Immunoprecipitation experiments with BMMCS transduced with the cell-permeable RGS13 indicated that RGS13 interfered with the recruitment of p85 to Gab2 of the FcεRI signaling complex. G. Bansal, Z. Xie, S. Rao, K. H. Nocka, K. M. Druey, Suppression of immunoglobulin E-mediated allergic responses by regulator of G protein signaling 13. Nat. Immunol. 9 , 73-80 (2008). [PubMed]

Neural Adrenergic/Cyclic AMP Regulation of the Immunoglobulin E Receptor α-Subunit Expression in the Mammalian Pinealocyte: A NEUROENDOCRINE/IMMUNE RESPONSE LINK?

The high affinity immunoglobulin E receptor (FcepsilonRI) complex is dedicated to immunoglobulin E-mediated allergic responses. Expression of the FcepsilonRI receptor is thought to be relatively stable and limited to mast cells, basophils, eosinophils, monocytes, Langerhans cells, platelets, and neutrophils. We now report that the FcepsilonRIalpha and FcepsilonRIgamma polypeptides are expressed in the pinealocyte, the melatonin-secreting cell of the pineal gland. Moreover, Fcer1a mRNA levels increased approximately 100-fold at night to levels that were higher than in other tissues examined. Pineal FcepsilonRIalpha protein also increased markedly at night from nearly undetectable daytime levels. Our studies indicate that pineal Fcer1a mRNA levels are controlled by a well described neural pathway that controls pineal function. This pathway includes the master circadian oscillator in the suprachiasmatic nucleus and passes through central and peripheral structures. The circadian expression of FcepsilonRIalpha in the pineal gland is driven by this neural circuit via an adrenergic/cyclic AMP mechanism. Pineal FcepsilonRIalpha and FcepsilonRIgamma may represent a previously unrealized molecular link between the neuroendocrine and immune systems.