Evidence for eosinophil activation in eosinophilic cystitis.

Eosinophilic cystitis (EC) is a rare condition. Recent studies have shown that activated eosinophils release cytotoxic cationic proteins which can induce tissue damage. Moreover, in vitro studies have shown that interleukin-5 (IL-5) is a cytokine able to attract and activate eosinophils.

[Eosinophil, beneficial or harmful: a cell entirely part of immune response].

The demonstration that human eosinophils could express various membrane receptors (for IgG, IgE, IgA; for complement; for cytokines; for chemotactic factors), for adhesion molecules (VLA4, LFAI, OKM1), as well as CD4 and class II MHC, has allowed to reconsider the role of eosinophils in immune response. Indeed, eosinophils can function as antigen presenting cells and can be infected by HIV. Studies on eosinophil mediators have revealed that eosinophils are not only the source of cytotoxic and proinflammatory mediators but can also release various cytokines and growth factors, including their own factors of differentiation (IL-3, GM-CSF and IL-5).

Synthesis of interleukin-5 by activated eosinophils in patients with eosinophilic heart diseases.

Eosinophilic endomyocardial disease represents a major evolutive risk in chronic eosinophilia-associated disorders. Eosinophil granule proteins appear to be involved in cardiac injury, but the mechanisms leading to eosinophil infiltration and degranulation are not clear. Interleukin-5 (IL-5) has been recently shown to be produced by eosinophils and might play a role in both chemoattraction and degranulation of eosinophils.

Cerebro-spinal fluid eosinophilia in shunt infections.

Hypereosinophilia has been detected in the CSF of 22 patients in a series of 81 cases of shunt infection. It was related with the evolution of the sepsis. Its persistence at the end of treatment appeared to predict later complications, septic or obstructive, and it could be the sign of latent infection.

Interleukin 5 messenger RNA expression by eosinophils in the intestinal mucosa of patients with coeliac disease.

Interleukin 5 (IL-5), the major factor involved in eosinophil differentiation, is produced by T cells or mast cells. In the present study, we found that eosinophils infiltrating the mucosa of four patients with active coeliac disease also express the IL-5 mRNA. No positive signal was obtained in normal duodenum tissues and in the cell infiltrate from patients submitted to gluten restriction.

[Digestive manifestations of food hypersensitivity in adults].

Food allergy, synonymous with food hypersensitivity (FHS), is defined as an immunologically-mediated adverse reaction to food. Initiation of FHS could result from a break in the immune mucosal barrier with abrogation of oral tolerance. Food hypersensitivity is mostly due to immediate-type reaction involving IgE-dependent mastocytes activation.