30 and 32 kDa outer membrane proteins of Bordetella pertussis as a modulator on promoting degranulation of mast cells

The correlation between the activities of the outer menbrane proteins （OMPs） of Bordetella pertussis and the lgE-mediated asthma was investigated in the present study, in which the OMPs of B. pertussis and their components were prepared by detergent treatment and chromatography, and the molecular weights of the OMPs components were determined by SDS-PAGE. The amounts of total as well as the ovalbumin （OVA）-specific IgE induced by dead B. pertussis whole bacterial vaccine on guinea pigs were detected by ELISA. Meanwhile, the effect of the OMPs and their components to promote the degranulation of guinea pig mast cells was observed by using the mast cell degranulation test, and ELISA assay was used to measure the histatmine levels in the supematants from the mast cell cultures. Histamine sensitive test was used to demonstrate the effects of the OMPs and their components to increase the histamine lethal sensitivity in mice. It was found that four components with molecular weights of 30, 32, 38 and 69 kDa could be obtained from the OMPs of B. pertussts, and the dead whole bacteria vaccine of B. pertussis had the ability to increase the levels of the total as well as the OVA-specific IgE in sera of guinea pigs. The OMPs and their 30 and 32 kDa components demonstrated significantly enhancing effect on the degranulation of guinea pig mast cells, and the histamine levels in the supematants from the mast cell culture treated with OMPs and their 30 and 32 kDa components were also significantly increased. It is evident that the strong adjuvant activity and the enhancing effect to degranulation of mast cells and the release of histamine of certain outer membrane components of B. pertussis could be demonstrated as revealed by the results of the present study, suggesting the possibility of a close relationship between the infection of vaccination with B. pertussis and the IgE-mediated asthma.

Heat induces adenosine triphosphate release from mast cells in vitro:a putative mechanism for moxibustion

OBJECTIVE:To investigate the role of adenosine triphosphate(ATP) purinergic signaling in mast cells(MCs) modulated by heat to further understand the molecular mechanisms of moxibustion.METHODS:Skin temperatures induced by monkshood cake moxibustion were evaluated by measuring the Neiguan acupoint(PC 6) from 31 participants with a digital thermocouple thermometer.Temperatures of 43 ℃ and 52 ℃ were applied to cultured human leukemia mast cell line HMC-1 in vitro.Calcium fluorescence was applied to detect intracellular Ca^(2+)([Ca^(2+)]_i).Extracellular ATP contents were measured by luciferin-luciferase assay.RESULTS:Maximum skin temperatures mostly ranged from 40-45 ℃,but some reached up to50 ℃.Both 43 ℃,and 52 ℃ induced MC degranulation,which was accompanied by an increase in[Ca^(2+)]_i and ATP release.Complexing extracellular Ca^(2+) with 5 mM ethylene glycol-bis(β-aminoethyl ether)-N,N,N',N'-tetraacetic acid(EGTA) inhibited the noxious heat-induced elevation of[Ca^(2+)]_i and prevented the enhanced ATP secretion by those cells at 52℃ but not 43 ℃.CONCLUSION:Monkshood cake moxibustion can generate heat sufficient to trigger cellular events of MCs,including degranulation,[Ca^(2+)]_i elevation,and ATP release,suggesting that purinergic signals originating from MCs are possibly the initiating response of acupoints to moxibustion.

Studies on the Specific Degranulation of Mast Cell Sensitized by Several Allergens in vitro

Food allergy is a major health issue worldwide. Mast cells play a very important role in the immediate hypersensitivity for which mast cell degranulation needs to be studied extensively. In this study, an approach was taken to study the characteristics of sensitized mast cell degranulation in vitro, which associated with the study of mast cells and animal models. BALB/c mice were immunized respectively by several food allergens, then blood and peritoneal mast cells were collected at different time points. A dynamic determination was carried out between mast cells and serumal IgE. Comparative analysis on sequential time points showed that there was a close coincidence between mast cell degranulation and IgE antibody titers in sensitized BALB/c mice. Furthermore, it is interesting that sensitized mast cells could implement specific degranulation against the challenges in vitro, but the closely tropomyosins induced mast cell degranulation displayed cross reactions. This is very similar to IgE resisting the allergens in vivo. The study disclosed some characteristics on mast cells, coming from sensitized BALB/c mice, degranulation in vitro.

Mast Cell Stabilizing,Antianaphylactic and Antihistaminic Activity of Coccinia grandis Fruits in Asthma

Coccinia grandis Linn(Curcubitaceae) is a climber herb cultivated throughout India.In traditional medicine fruits have been used to treat leprosy,fever,asthma,bronchitis and jaundice.In present study,ethanol extract of C.grandis fruit(ECGF) at 100,125 and 150 mg·kg-1,i.p.,was evaluated for mast cell stabilizing,antianaphylactic and antihistaminic activity using egg albumin induced mast cell degranulation in mice;passive cutaneous anaphylaxis in rats and clonidine induced catalepsy in mice respectively.ECGF at(100-150 mg·kg-1,i.p.) significantly protected egg albumin induced degranulations of mast cells and caused reduction of blue dye leakage in passive cutaneous anaphylaxis in dose dependently.The treatment ECGF also inhibited clonidine induced catalepsy in dose dependent manner.Phytochemical studies observed presence of saponin,steroids,alkaloids,flavonoids and glycosides.In conclusion ECGF possesses mast cell stabilizing;anti anaphylactic and antihistaminic potential which might be used in treatment of asthma.

Panax Notoginseng Saponins Restrains Ischemia-reperfusion-induced Rat Mesenteric Microcirculatory Disturbance

Objective: To investigate the effect of Panax notoginseng saponins(PNS) on ischemia reperfusion(I/R) induced rat mesenteric microcirculatory dysfunctions.Methods: Male Wistar rats weighting 200–250 g were subjected to 10 min ligation of the superior mesenteric artery and vein, followed by60 min reperfusion. PNS(5 mg/kg/hr) was continuously administrated starting from 10 min before ischemia or 10 min after reperfusion until60 min after reperfusion via left jugular vein. Leukocytes adhesion, mast cell degranulation, endothelial peroxidation, and albumin leakage of rat mesenteric venules were observed. Serum myeloperoxidase(MPO) level, intercellular adhesion molecule-1(ICAM-1) expression and Src phosphorylation were examined.Results: PNS ameliorated leukocyte adhesion and mast cell degranulation, while with no obvious effects on endothelial peroxidation and albumin leakage. In addition, PNS inhibited serum MPO increase, intestinal ICAM-1 expression and Src phosphorylation induced by I/R.Conclusions: PNS ameliorated I/R-induced leukocyte adhesion and mast cell degranulation, the former is related to its inhibition of Src phosphorylation and ICAM-1 expression.