Attraction Of Eosinophils Research Articles

Mechanisms of eosinophil accumulation around eggs ofSchistosoma japonicum: Role of two purified components, allergen and eosinophil chemotactic factor, from soluble egg antigens measured on sensitized guinea pig skin

Mechanisms of eosinophil response induced by soluble egg antigen (SEA) in Schistosoma japonicum-infected guinea pig tissues were analyzed using two purified components of SEA: major allergenic components (JEAL) and a major eosinophil chemotactic component (ECF-SjE). Eosinophil response to the crude SEA of S. japonicum was detected at the injection site mainly at 2-8 h after the antigenic challenge; this response consisted of two different phases of eosinophil attraction. An early phase (2 h) was mediated by an immediate-type hypersensitivity reaction; JEAL played an important role in mediating this phase of eosinophil response. A late phase (8 h) was mediated by ECF-SjE. Therefore, this phase of eosinophil response was caused by direct eosinophilotactic activity of SEA. These two types of eosinophil response must be important processes in the formation of S. japonicum egg-associated eosinophilic granuloma.

The formation of eosinophil and neutrophil chemotactic activity during a pollen season and after allergen challenge

Heat-stable (HS) and heat-labile (HL) neutrophil chemotactic activities (NCAs) have been demonstrated in serum after allergen challenge of subjects with asthma. In this investigation, we have studied the possible occurrence of similar activities in 20 atopic individuals on natural exposure to allergen, that is, during the birch-pollen season. Since eosinophil accumulation is a hallmark of an ongoing allergic inflammation in the respiratory tract also, the possible production of eosinophil chemotactic activity (ECA) was examined in serum after allergen challenge and at natural exposure to pollen. Both HL-NCA and HL-ECA were produced to a significant extent ( p < 0.001) during the season, with the peak of activities occurring simultaneously with the peak pollen count. HL-ECA was produced after allergen challenge of subjects with asthma in the laboratory, as has been demonstrated for NCA previously. The activity of the HS-NCA was unaltered during season. Gel-filtration studies of the major HL-NCA and HL-ECA indicated a molecular weight for both activities of 100 to 150,000, and the activities produced during season cocromatographed with the HL-NCA and HL-ECA produced after allergen challenge in the laboratory, suggesting that all these activities are due to one and the same molecule. The results suggest that the heat-labile chemotactic activity found in serum of atopic subjects and subjects with asthma after allergen exposure may be involved in the attraction of eosinophils and neutrophils to the site of allergic inflammation.

Inhibition of Human Eosinophil Chemotaxis and of the IgE-Dependent Stimulation of Human Blood Platelets by Cetirizine

Cetirizine is a new anti-allergic compound with a potent, long-acting, and specific antihistaminic property. Strongly active in the therapy of urticaria and seasonal or perennial rhinitis, it has been shown to inhibit the in vivo eosinophil attraction at skin sites challenged with allergen in atopic patients. In the present work, we confirmed that, at a therapeutical concentration, this molecule had a potent inhibitory action in vitro on eosinophil chemotaxis induced either by N-formyl-Met-Leu-Phe or platelet-activating factor and also on the IgE-dependent stimulation of platelets. These observations appear in favour of a possible role for cetirizine in the modulation of inflammatory cell interactions in allergic processes.

Inhibition of eosinophil chemotaxis by a new antiallergic compound (cetirizine).

The in vivo inhibitory effect of a new antiallergic, anti-H1 drug, cetirizine, on eosinophil attraction at skin sites challenged with various stimuli has been recently suggested. In the present work, we confirmed that this molecule, at therapeutical concentration, has a potent inhibitory action on eosinophil response to different chemoattractant mediators such as platelet-activating factor (PAF acether) and N-formyl methionyl leucyl phenyl alanyl in vitro. Another anti-H1 drug, polaramine, did not show this effect at the same concentration. These findings suggest that cetirizine in addition to its antihistaminic effect could also play a direct inhibitory effect on eosinophil recruitment. Moreover, cetirizine was not toxic for eosinophils and did not induce degranulation, as shown by the absence of peroxidase release. Comparison between cetirizine and a PAF acether antagonist (BN 52021) suggested that cetirizine did not act by a PAF receptor-blocking activity.

Generation of leukotrienes from normal epidermis and their demonstration in cutaneous disease.

In order to evaluate the significance of chemotactic leukotrienes in cutaneous disease, synthetic leukotriene B4 and its metabolites were examined during in vitro chemotaxis. Leukotriene B4, and less so 20-OH-leukotriene B4, were chemotactic for neutrophils and eosinophils, with a preferential attraction of eosinophils. The responsiveness of human monocytes towards leukotriene B4 was relatively low. Normal cells and cells from different patients varied in their quantitative response. Cells from patients with eczema and T-cell lymphoma tended to migrate less than those from patients with other inflammatory diseases. Leukotrienes are generated from several types of peripheral leukocytes. In order to examine whether resident cells of the skin can also produce these factors, isolated human and murine epidermal cells were examined for their ability to generate leukotriene B4 and leukotriene C4 in vitro. Arachidonic acid, and less so the ionophore A 23187, induced the generation of both types of factors, based on the finding in the bioassay, reverse-phase high-pressure liquid chromatography and radioimmunoassays. The same factors were demonstrated by either or all of these methods in skin biopsies, scales, blisters or suction blisters of patients with psoriasis, pitysiasis rubra pilaris, dyshidrosis, bullous pemphigoid, pressure urticaria, urticaria pigmentosa and drug reactions, but not in Sézary syndrome nor in callus and skin biopsies of normal controls. These findings underline the fact that the leukotrienes are potent inflammatory mediators in diverse skin diseases, but that they are not limited to any specific disease. Furthermore, a relationship between leukotrienes and tissue eosinophilia does not exist.

Effect of Neutrophil-derived Eosinophil Chemotactic Factor (ECF) in Human and Guinea Pig Skin

The in vivo effectiveness of eosinophil chemotactic factor (ECF), secreted in vitro by human neutrophils (PMN) during phagocytosis, is tested in 2 model systems. Injection of ECF into guinea pig ears causes a preferential attraction of eosinophils with time that is more marked in animals with preexisting eosinophilia. In the same model system, activated serum attracts fewer eosinophils and more PMN. In human skin windows, ECF and activated serum are equally effective on a quantitative basis, but ECF is more selective for eosinophils in patients with eosinophilia. With normal controls, ECF and activated serum attract PMN equally well. The studies confirm previous in vitro observations on the properties of ECF and suggest a potentially significant role of this factor during pathological processes.

Eosinophil chemotactic factor release from neutrophils by Nippostrongylus brasiliensis larvae.

INFESTATIONS with metazoan parasites are the most efficient stimulus known for the induction of eosinophilia, and eosinophils have been shown to have an essential role in the elimination of worms1,2. Eosinophil chemotactic factors have been derived from lymphocytes3–5, mast cells6 and the complement system7. We reported recently the in vitro release of a low molecular weight eosinophil chemotactic factor, ECF, from human neutrophils (PMN) during phagocytosis of zymosan8. The evidence presented here shows that neutrophils, after incubation with larvae of Nippostrongylus brasiliensis (N.B.), can also generate this same factor which selectively attracts eosinophils in vitro. As neutrophils are the first cells to accumulate at tissue sites where parasites are located9–11, the attraction of eosinophils may present an early line of defence against the invading organism.

Dynamics of Eosinophils in the Uterus after Oestrogen Administration

To investigase the role of the eosinophil leukocytes in the early oestrogenic responses in the uterus, the kinetics of oestrogen-induced uterine eosinophilia and other parameters of oestrogen stimulation were studied at very early times. Uterine eosinophils increase as early as 5 min after an intravenous injection of oestradiol to immature rats, much earlier than several other changes in the early parameters of oestrogen stimulation. Large number of uterine eosinophils are found attached to the wall of small uterine blood vessels at early times. To elucidate the mechanisms involved in the specific attraction of eosinophils to the uterus in the presence of oestrogens, the in vivo localisation of oestrogens in the rat uterus at early times was studied using a radioautographic technique. Oestrogen receptors were found in the surface of eosinophils and in the wall of small uterine blood vessels. This simultaneous presence of both oestrogen receptors is proposed to explain the specific attachment of eosinophils to uterine blood vessels in the presence of oestrogens, which is the initial step toward eosinophil penetration into the uterus.

A SIMPLE METHOD OF BLOOD TRANSFUSION IN INFANCY

The majority of patients affected by chronic rhinosinusitis (CRS) suffer from eosinophilic infiltration. We hypothesised that polihexanide and polyethylene glycol as an antiseptic might alter the eosinophil-associated IL-5 and eotaxin-3 expression in CRS and also the expression of MMP-9, being involved in the tissue-remodelling in CRS. After obtaining samples from 10 CRS patients with (CRSwNP) and without nasal-polyposis (CRSsNP) and 2 patients with inverted-papilloma undergoing functional endoscopic sinus surgery (FESS), the expression of interleukin-5, eotaxin-3 and MMP-9 were evaluated by an ELISA assay with and without the tested agent. CRSwNP showed a significantly increased expression of IL-5. Polihexanide seems not to alter the attraction of eosinophils in patients with CRS via IL-5 expression. Also elevated levels of MMP-9 could not be reduced to normal values. But there exists statistically significant evidence that the self-amplification process of eosinophils via eotaxin-3 could be influenced by the administration of polihexanide.