Rat Basophilic Leukemia Cell Line Research Articles

Degranulation of RBL-2H3 rat basophilic leukemia cells is synergistically inhibited by combined treatment with nobiletin and lactoferrin.

The aim of this study was to elucidate the anti-allergic effects of polymethoxyflavonoids in combination with milk proteins and the mechanism of inhibition. Three polymethoxyflavonoids and two milk proteins were exposed to the rat basophilic leukemia cell line RBL-2H3. β-hexosaminidase was used as an indicator of degranulation inhibition. The mechanism of inhibition was examined by measuring intracellular Ca2+ levels and western blot method. In the degranulation inhibition test with polymethoxyflavonoids and milk proteins alone, nobiletin was the strongest inhibitor in the polymethoxyflavonoid group and lactoferrin in the milk protein group. Next, co-stimulation with nobiletin and lactoferrin showed stronger synergistic degranulation inhibition than treatment with nobiletin or lactoferrin alone. Western blot analysis showed that co-stimulation with nobiletin and lactoferrin significantly downregulated the induction of phospholipase Cγ 1 phosphorylation. The degranulation response in RBL-2H3 cells was synergistically suppressed by co-stimulation of nobiletin and lactoferrin acting on both Ca2+-dependent and Ca2+-independent pathways.

Mechanism of Action of Yikun Yitong Ping-Containing Serum on Mast Cells and its Possible Involvement in Endometriosis-Related Dysmenorrhea

Background Previously, we showed that Yikun Yitong Ping (YKYTP) can effectively and safely relieve endometriosis-related dysmenorrhea; however, the underlying mechanism remained unclear. This study aimed to assess the effects of YKYTP-containing serum on rat basophilic leukemia cell line, as mast cells (MCs) analog, and investigate the mechanisms by which YKYTP alleviates endometriosis-related dysmenorrhea. Method In this study, YKYTP drug-containing serum was used to treat rat basophilic leukemia cell line (RBL2H3). The effect of YKYTP-containing serum on the expression of ER-α, ER-β, NGF, and NGFRp75 in RBL2H3 cells was evaluated using enzyme-linked immunosorbent assay, quantitative real-time polymerase reaction, and Western blotting. Results Different concentrations (5%-40%) of YKYTP-containing serum reduced ER expression in RBL2H3 cells, and the optimum concentration was 40%. Compared to the blank group, the expression of ER and NGF significantly increased in the E2 group ( P < .01). After co-administration with YKYTP-containing serum, the expression of ER-α, ER-β, NGF, and P75 significantly decreased ( P < .01). Conclusion YKYTP-containing serum can efficiently inhibit the expression of ER-α, ER-β, NGF, and P75 in RBL2H3 cells. YKYTP may alleviate endometriosis-related dysmenorrhea by downregulating ER expression in MCs.

Isolation and Quantification of 2-O-Caffeoyl-hydroxycitric Acid, an Active Component in Hot Water Extracts of Coriander (Coriandrum sativum L.), Which Inhibits Degranulation of RBL-2H3 Cells

Objectives: Natural compounds that can effectively prevent and alleviate allergic symptoms, such as hay fever, are widely sought after from sources such as natural ingredients that can be ingested daily. Coriander extracts have been reported to show anti-allergic activity; however, hot water extracts have not been tested previously. Here, we found that a hot water extract of the aerial parts of coriander inhibited the degranulation of rat basophilic leukemia cell line RBL-2H3 cells and identified the active compounds. Methods: Chromatographic methods were used to isolate compounds from the hot water extract of coriander. The chemical structures were elucidated by analyses of high-resolution electrospray ionization mass spectrum and nuclear magnetic resonance spectral data. The degranulation activity of compounds was evaluated using the β-hexosaminidase release assay. Results: We analyzed the components to identify active compounds. 2 S,3 S-2- O-caffeoyl-hydroxycitric acid (1), and 2- O-caffeoyl-hydroxycitric acid 6′- O-methyl ester (2) were isolated from the hot water extract of coriander, and both compounds showed degranulation inhibitory activity in RBL-2H3 cells at a concentration below 2.5 mM. The content of compound 1 in the freeze-dried coriander powder was calculated to be 2.0% via HPLC quantification. Conclusions: Compound 1 was considered to be the primary active contributor in the hot water extract of coriander.

IRF3 Activation in Mast Cells Promotes FcεRI-Mediated Allergic Inflammation.

(1) Background: This study aims to elucidate a novel non-transcriptional action of IRF3 in addition to its role as a transcription factor in mast cell activation and associated allergic inflammation; (2) Methods: For in vitro experiments, mouse bone-marrow-derived mast cells (mBMMCs) and a rat basophilic leukemia cell line (RBL-2H3) were used for investigating the underlying mechanism of IRF3 in mast-cell-mediated allergic inflammation. For in vivo experiments, wild-type and Irf3 knockout mice were used for evaluating IgE-mediated local and systemic anaphylaxis; (3) Results: Passive cutaneous anaphylaxis (PCA)-induced tissues showed highly increased IRF3 activity. In addition, the activation of IRF3 was observed in DNP-HSA-treated mast cells. Phosphorylated IRF3 by DNP-HSA was spatially co-localized with tryptase according to the mast cell activation process, and FcεRI-mediated signaling pathways directly regulated that activity. The alteration of IRF3 affected the production of granule contents in the mast cells and the anaphylaxis responses, including PCA- and ovalbumin-induced active systemic anaphylaxis. Furthermore, IRF3 influenced the post-translational processing of histidine decarboxylase (HDC), which is required for granule maturation; and (4) Conclusion: Through this study, we demonstrated the novel function of IRF3 as an important factor inducing mast cell activation and as an upstream molecule for HDC activity.

Development of a Water-Dispersible Supramolecular Complex of Polyphenol with Polypeptides for Attenuation of the Allergic Response using a Mechanochemical Strategy.

The prevalence of allergic disorders has increased worldwide in recent decades. Polyphenols, including resveratrol and curcumin, are posited to have potential as therapeutic agents for allergy; however, their use has been limited by poor water solubility. Accordingly, a highly concentrated, water dispersible, supramolecular complexes of polyphenols with polypeptides (poly-L-lysine, poly-γ-glutamic acid) and gelatin using high-speed vibration milling are developed. The complex exhibits resistance to photobleaching and thermal radiation. Treatment of a rat basophilic leukemia cell line (RBL-2H3) with polypeptide complexes containing resveratrol is suppressed allergic responses in vitro. Moreover, aerosolized administration of polypeptide complexes demonstrates excellent bioavailability and inhibition of immediate hypersensitivity reactions in ear tissue in vivo. Furthermore, the method avoids the use of organic solvent and therefore reduces undesirable biological responses.

Identification of components in coriander (Coriandrum sativum L.) inhibiting degranulation of RBL-2H3 cells

We found that a water-soluble extract of coriander (Coriandrum sativum L.) (leaves, petioles and stems) inhibits antigen-induced degranulation of RBL-2H3 cells, a rat basophil leukemia cell line. The aim of this study was to elucidate the anti-degranulation active components in the extract. The methanol-eluate fraction obtained by fractionation of the water-soluble extract using MCI gel column chromatography had strong activity, and eight components were isolated and identified. Two of them were identified as new compounds, (3S)-3-methyl-6-hydroxyisocoumarin 8-O-β-D-glucopyranoside (compound 1) and (7S,8R)-7,8-dihydro-8-β-D-glucopyranosyloxy-4-methoxy-7-methyl-5H-fro[2,3-g][2]benzopyran-5-one (compound 2). As a result of evaluation of anti-degranulation activity of eight components, seven of them, such as tryptophan, phenylalanine, dihydroxycoumarin glucoside, quercetin glycoside, rutin, compound 1, and compound 2, had the activity. These results indicated that the water-soluble extract of coriander contains several anti-degranulation substances.

A Traditional Medicine-Based Combination of Bamboo Salt and Egg White-Chalcanthite Ameliorates Atopic Dermatitis

Bamboo salt and egg white-chalcanthite mixture has been prescribed for relieving the inflammation of atopic dermatitis in Hamyang, Gyeongsangnam-do, Korea. This study was conducted to demonstrate the effect of atopic dermatitis on cell and atopic animal models using a combination of bamboo salt with egg white-chalcanthite, which have been used as folk remedies for inflammatory conditions. Based on the in vitro experiment, the 1:20 mixture of egg white-chalcanthite and bamboo salt was shown to inhibit the release of beta-hexosaminidase and histamine in rat basophilic leukemia cell line RBL-2H3 by sensitizing immunoglobulin E and inducing allergic responses by dinitrophenyl as well as the expression of inflammatory cytokines and inflammatory mediators in a dose-dependent manner in lipopolysaccharide-treated mouse macrophage cell line RAW 264.7 cells. Furthermore, egg white-chalcanthite with bamboo salt and its combination at different mixing ratios showed a decrease in inflammatory mediators. Dinitrochlorbenzene was applied to NC/Nga mice for 6 w to induce the atopic in vivo model. After 4 w administration of the test substance, the dermatitis decreased visually and dermal hyperplasia/inflammation, mast cell/eosinophils counts and degree of nerve fiber infiltration were decreased according to histopathological examination. In addition, the secretion rate of interferon gamma in high-dose treated group was lower than that in atopic dermatitis control group. These results show that bamboo salt with egg white-chalcanthite effectively relieves skin inflammation in atopic dermatitis and it might be a promising mineral agent for relieving the symptoms of atopic dermatitis.

Valdecoxib blocks rat TRPV2 channels

The transient receptor potential vanilloid 2 (TRPV2) channel is broadly expressed in a multitude of different tissues and is implicated in the pathology of several diseases, such as the progression of different cancer types. However, a lack of specific, potent and non-toxic TRPV2 activators and inhibitors complicate further studies to clarify the role of TRPV2. We here present valdecoxib as a novel inhibitor of heterologously expressed rat TRPV2 channels in HEK293 cells and native TRPV2 channels, endogenously expressed in the rat basophilic leukemia (RBL-2H3) cell line. Fluorometric assays reveal an IC50 of 9 μM and 11 μM for TRPV2 in HEK293 and RBL-2H3 cells, respectively. Closely related TRPV1, TRPV3 or TRPV4 channels are not blocked by valdecoxib. The inhibition is reversible and direct as confirmed by whole-cell and excised inside-out electrophysiological recordings. Other cyclooxygenase-2 inhibitors do not affect TRPV2 activity. Furthermore, we demonstrate that the combined application of 2-aminoethoxydiphenyl borate (2-APB) and probenecid at concentrations, which, on their own, elicit only small TRPV2 currents, act in a highly synergistic manner when applied simultaneously. Taken together, we here provide novel tools and chemical lead structures for further studying TRPV2 channel function in native tissues.

Antiallergic activities of Japanese leaf burdock extract in a rat basophilic leukemia cell line.

Although primarily cultivated for its edible root, the leaves and stems of "Japanese leaf burdock (Arctium lappa L)" are also edible. This study determined the antiallergic activity of root, leaf, and stem extracts of Japanese leaf burdock using the rat basophilic leukemia cell line. We demonstrate that the hot water extract of Japanese leaf burdock stems has a strong inhibitory effect on antigen-stimulated degranulation. This extract was further fractionated into five fractions using a glass column. The fraction obtained with 99% ethanol extracts (99% EtEx) elicits a concentration-dependent increase in degranulation inhibition. One of antiallergic compounds from the separation of components of the 99% EtEx fraction using high-performance liquid chromatography and mass spectrometry analyses had a value of m/z 393.16. From these results and those of previous studies, one of the antiallergic components was hypothesized to be onopordopicrin. Our findings demonstrate that the extract of Japanese leaf burdock exerts a strong antiallergic activity. PRACTICAL APPLICATIONS: "Japanese leaf burdock (Arctium lappa L)" is a traditional Japanese vegetable with edible leaves and stems. The antiallergic activity of the hot water extracts has been shown in vitro. One of the antiallergic components was hypothesized to be onopordopicrin. Therefore, "Japanese leaf burdock" could serve as a functional food for patients with allergic disorders, such as allergic rhinitis.

Humanized Mediator Release Assay as a Read-Out for Allergen Potency.

Mediator release assays analyze in vitro immunoglobulin E (IgE)-mediated degranulation and secretion of mediators by effector cells, such as mast cells and basophils, upon stimulation with serial dilutions of putative allergens. Therefore, these assays represent an essential tool that mimics the in vivo degranulation process, which occurs upon allergen exposure in sensitized patients or in skin prick tests. Additionally, these assays are usually employed to investigate the allergenic potential of proteins and the reactivity of patients' sera's reactivity. Herein, we describe a simple 2-day protocol using an immortalized rat basophil leukemia cell line transfected and humanized with the human high-affinity IgE plasma-membrane receptor (FcεRI). This variant of the mediator release assay is a robust, sensitive, and reproducible in vitro cell-based system without the need to immobilize the antigen to solid matrices. The protocol consists of the following steps: (1) complement inactivation of human sera, (2) harvesting, seeding, and passive sensitization of the cells, (3) stimulation with antigen to cause mediator release, and (4) measuring of β-hexosaminidase activity as a surrogate for the released inflammatory mediators, such as histamine. The assay represents a useful tool to assess the capacity of the allergen-IgE cross-linking to trigger cell degranulation and can be implemented to standardize allergen extracts, to compare patients' reactivity to minor or major allergens and to allergenic extracts (pollen, cat dander, etc.), to investigate the potency of allergen homologs, isoforms, and fold-variants (e.g., hypoallergenicity), as well as the effects of ligands on the allergenic activity. A more recent application includes the use of the assay to monitor the treatment efficacy in the course of allergen immunotherapy.

Terahertz radiation may not alter rat basophilic leukemia cell membrane permeability to propidium iodide

Terahertz radiation (THz) technology is fast-growing, with applications in sensing, security, monitoring and pharmaceutical industries. Since it is non-invasive, THz has been used as a diagnostic and therapeutic tool in medicine but its specific effects on biological systems is still largely under-studied. THz has been used to image tissues and cells mainly because it allows for identification of morphological features without the need for fluorescent or radioactive labels, but the potential effects of high intensities of THz radiation are currently not well understood. One of the hypotheses that has been proposed for possible effects of THz on living cells, is that it disrupts the cell membrane and induces increased permeability. To test this hypothesis we exposed a rat basophilic leukemia cell line (RBL-2H3) to non-thermal intense THz radiation (duration, dose, etc) and observed the internalization of propidium iodide, a fluorescent intercalating agent that binds to DNA. We did not observe any changes in RBL-2H3 fluorescence following exposure to these intense THz pulses suggesting that exposure of RBL-2H3 to THz radiation may not increase their membrane permeability. These experiments were preliminary and further optimization and analysis is required before we can make definitive conclusions. However, our preliminary observations have set a baseline of RBL-2H3 internalization of propidium iodide, show that it is possible to expose RBL-2H3 cells to THz radiation using our configuration, and set the stage for future experiments.

Bioelectrochemical detection of histamine release from basophilic leukemia cell line based on histamine dehydrogenase-modified cup-stacked carbon nanofibers

Histamine released from mast cells plays an important role as not only a physiological active substance for the trigger of allergic reactions but also a neurotransmitter in a nervous system. To detect histamine directly, we immobilized oxygen-independent histamine dehydrogenase (HmDH) onto the surface of cup-stacked carbon nanofibers (CSCNFs), which work both as an electrical nanowire and an enzyme support, and investigated the direct electron transfer reaction from HmDH reduced by histamine to CSCNF. Current responses of histamine oxidation at the HmDH-modified CSCNF electrode showed a linear relationship between 0.3 µM and 300 µM with detection limit of 0.1 µM in a Briton Robinson buffer (pH 9.4) and was about 25 times larger than those at a flat glassy carbon electrode modified with HmDH because of its three-dimensional network. Using the HmDH-modified CSCNF electrode, we successfully observed histamine release from rat basophilic leukemia cell line RBL-2H3 after stimulation with degranulation agents, such as antigen 2,4-dinitrophenylated bovine serum albumin and calcium ionophore A23187. The present sensing system might be applied to at least advanced in vitro allergic diagnostic methods.

Tricin Isolated from Enzyme-Treated Zizania latifolia Extract Inhibits IgE-Mediated Allergic Reactions in RBL-2H3 Cells by Targeting the Lyn/Syk Pathway.

Tricin, a flavone present in rice bran, is confirmed as the major efficacious compound present in the enzyme-treated Zizania latifolia extract (ETZL), which protects against UVB-induced skin-aging. However, the suppressive mechanism of tricin on allergic responses remains unknown. The present study, therefore, aimed to determine the mechanisms of tricin and ETZL on mast cell degranulation in IgE-activated rat basophilic leukemia cell line (RBL-2H3) cells. We investigated the regulatory effects of tricin and ETZL on degranulation, production of cytokines and lipid mediators, and signaling proteins involved in the IgE-bound high-affinity IgE receptor activation, mitogen-activated protein kinase, arachidonic acid and Syk. The production of β–hexosaminidase, tumor necrosis factor-α, interleukin-4, leukotrienes (LT) B4, LTC4 and prostaglandin E2 in IgE-stimulated RBL-2H3 cells were significantly inhibited by exposure to tricin or ETZL. Moreover, tricin and ETZL inhibit the phosphorylation of cytosolic phospholipase A2, 5-lipoxygenase and cyclooxygenase-2. Furthermore, the phosphorylation of Akt, ERK, p38, JNK, protein kinase Cδ and phospholipase Cγ1 were effectively suppressed by both samples. Exposure to tricin or ETZL also significantly decreases the phosphorylation of Lyn and Syk, but has minimal effect on Fyn. Taken together, our data indicate that tricin and ETZL are potential anti-allergic materials that could be applied for the prevention of allergy-related diseases.

Trigonelline: An alkaloid with anti-degranulation properties

Trigonelline, one of the alkaloids contained in coffee, is important not only as one of the constituents of aroma and flavor in coffee but also as a useful source of nutrition. Its anti-microbial, anti-carcinogenic, and anti-hyperglycemic effects have been investigated in previous studies. However, there have not been any studies examining the anti-degranulation effect of trigonelline. In this study, the anti-degranulation effect of trigonelline was evaluated in in vitro and in vivo models using a rat basophilic leukemia cell line, RBL-2H3 cells, and a passive cutaneous anaphylaxis (PCA) reaction in mice, respectively. In the β-hexosaminidase release assay, trigonelline effectively suppressed antigen-induced degranulation of RBL-2H3 cells in a dose-dependent manner without cytotoxicity. Trigonelline also inhibited FcεRI-mediated intracellular signaling pathways, such as phosphorylation of PLCγ1, PI3 K, and Akt, in antigen-stimulated RBL-2H3 cells and suppressed the PCA response in mice. Moreover, trigonelline also inhibited the microtubule formation in RBL-2H3 cells, indicating that trigonelline could inhibit IgE-sensitized mast cell degranulation by attenuating both the intracellular calcium-dependent and independent pathways. These results revealed that trigonelline possesses the anti-degranulation effect against the development of allergic diseases.

Effect of tyrosinase and caffeic acid crosslinking of turbot parvalbumin on the digestibility, and release of mediators and cytokines from activated RBL-2H3 cells

Turbot can induce allergy in susceptible individuals due to the presence of parvalbumin (PV), a major fish allergen. This study aimed at evaluating the digestibility and the ability of PV to elicit the release of cellular degranulation, following treatment with tyrosinase (PV-Tyr), caffeic acid (PV-CA) and in combination (PV-Tyr/CA), using in vitro digestion and RBL-2H3 (passive rat basophil leukemia) cell line. The digestion assay products revealed that the stability of PV in simulated gastric fluid (SGF) was stronger, while in simulated intestinal fluid (SIF) was rather weak. Western blot analysis revealed that the IgG-binding abilities of the cross-linked PV were markedly reduced. Moreover, crosslinking hampered the release of cellular degranulation process in RBL-2H3 cell lines. PV-Tyr/CA showed highly significant reduction in the release rate of β-hexosaminidase (66.02%), histamine (35.01%), tryptase (29.25%), cysteinyl leukotrienes (29.72%), prostaglandin D2 (34.96%), IL-4 (43.99%) and IL-13 (38.93%) and shown potential in developing hypoallergenic fish products.

Inhibitory effect of aqueous extract of Cuminum cyminum L. seed on degranulation of RBL-2H3 cells and passive cutaneous anaphylaxis reaction in mice.

Cuminum cyminum L. (cumin) seed is used as a spice in various countries. Although several functions of the components in cumin seed have been reported, the anti-allergic effect of the water-soluble component in cumin seed has not been reported yet. In this study, we focused on the suppressive effect of cumin seed aqueous extract on degranulation in order to reveal the anti-allergic effect of cumin. Cumin seed aqueous extract significantly suppressed the antigen-induced degranulation of rat basophilic leukemia cell line RBL-2H3 cells in a dose-dependent manner without cytotoxicity. The extract also inhibited the elevation of the intracellular calcium ion concentration induced by antigen. Immunoblot analysis revealed that the extract suppresses phosphorylation of phosphatidylinositol 3-kinase, Bruton's tyrosine kinase, phospholipase C-γ1/2, and Akt in the signaling pathways activated by antigen induction via FcεRI. Furthermore, the extract suppressed microtubule formation induced by antigen. In addition, oral administration of cumin seed aqueous extract significantly suppressed the passive cutaneous anaphylaxis reaction in BALB/c mice. Our findings suggest that cumin seed contains water-soluble components with the anti-allergic effect. Therefore, cumin seed has potential as anti-allergic functional food.

Proteinase 3 Interferes With C1q-Mediated Clearance of Apoptotic Cells.

Proteinase 3 (PR3) is the autoantigen in granulomatosis with polyangiitis, an autoimmune necrotizing vasculitis associated with anti-neutrophil cytoplasmic antibodies (ANCAs). Moreover, PR3 is a serine protease whose membrane expression can potentiate inflammatory diseases such as ANCA-associated vasculitis and rheumatoid arthritis. During apoptosis, PR3 is co-externalized with phosphatidylserine (PS) and is known to modulate the clearance of apoptotic cells through a calreticulin (CRT)-dependent mechanism. The complement protein C1q is one mediator of efferocytosis, the clearance of altered self-cells, particularly apoptotic cells. Since PR3 and C1q are both involved in the clearance of apoptotic cells and immune response modulation and share certain common ligands (i.e., CRT and PS), we examined their possible interaction. We demonstrated that C1q binding was increased on apoptotic rat basophilic leukemia (RBL) cells that expressed PR3, and we demonstrated the direct interaction between purified C1q and PR3 molecules as shown by surface plasmon resonance. To better understand the functional consequence of this partnership, we tested C1q-dependent phagocytosis of the RBL cell line expressing PR3 and showed that PR3 impaired C1q enhancement of apoptotic cell uptake. These findings shed new light on the respective roles of C1q and PR3 in the elimination of apoptotic cells and suggest a novel potential axis to explore in autoimmune diseases characterized by a defect in apoptotic cell clearance and in the resolution of inflammation.

Anti-allergic Effects of the Alkaline Hydrolysis of Rapeseed Cake in a Rat Basophilic Leukemia Cell Line (RBL-2H3)

Anti-allergic Effects of the Alkaline Hydrolysis of Rapeseed Cake in a Rat Basophilic Leukemia Cell Line (RBL-2H3)

Digestion differently affects the ability of native and thermally aggregated ovalbumin to trigger basophil activation

Ovalbumin (OVA), a major allergen from hen's egg albumen, tends to aggregate when heated. Depending on the balance of attractive and repulsive interactions, heat-induced OVA aggregates have various morphologies, which differ in digestibility. In the context of food allergy to egg, we investigated the ability of native and thermally aggregated OVA as well as their digests to induce the degranulation of a humanized rat basophil leukemia (RBL) cell line, which was sensitized with a pool of sera from egg-allergic children. Native and two thermally aggregated OVA forms were digested in vitro using a gastrointestinal digestion model based on the INFOGEST harmonized protocol including a final degradation with jejunal brush border membranes (BBM) enzymes. The course of digestion was monitored by the OPA method and by RP-HPLC. Digestibility was OVA small aggregates>OVA large aggregates>>native OVA and BBM peptidases only significantly hydrolyzed small-sized peptides from gastro-duodenal digests of the aggregates. The degranulation ability of the native OVA slightly changed during the gastric phase but mostly decreased during the duodenal digestion with no further change with BBM digestion. The degranulation ability of aggregates, which was significantly lower than the ability of native OVA, was not significantly affected by digestion. Digestibility and ability to induce basophil degranulation can thus not be straightforward linked.

Is Andrographis paniculata extract and andrographolide anaphylactic?

Andrographis paniculata, "King of bitters" is a popularly known medicinal plant extensively used in many parts of the world for treatment of various diseases. Since recent past, anaphylactic/allergic type adverse events were reported upon A. paniculata usage, the study aimed to evaluate the anaphylactic and anaphylactoid potential of A. paniculata extract and andrographolide (a major phytoactive of A. paniculata). The anaphylactic potential was evaluated using active systemic anaphylaxis (ASA) assay in guinea pigs. Further, the release of allergic mediators was measured in immunoglobulin E (IgE) sensitized and non-IgE sensitized Rat Basophilic Leukemia (RBL-2H3) cell lines in-vitro. A. paniculata extract or andrographolide sensitized guinea pigs following the challenge antigen administration orally and intravenously did not demonstrate any clinical signs of anaphylaxis. IgE sensitized and non- IgE sensitized RBL-2H3 cells treated with A. paniculata extract did not induce release of allergic mediators. Whereas IgE sensitized and non- IgE sensitized RBL-2H3 cells treated with andrographolide demonstrated mild to moderate release of allergic mediators. A. paniculata extract has no anaphylactic and anaphylactoid potential in in-vivo and in-vitro studies. Whereas, andrographolide effects on allergic mediators in in-vitro studies needs to be scrutinized if they are of biologically important.