Characterization of synthetic C3a analog peptides on human eosinophils in comparison to the native complement component C3a.

The C3a anaphylatoxin is a potent proinflammatory mediator derived from the complement system inducing biologic effects of human eosinophils like Ca2+ transients and the activation of the respiratory burst. These findings support an important role for C3a in diseases typically associated with a peripheral blood or tissue eosinophilia. Synthetic human C3a analogue peptides with variations at the C-terminal effector domain have been evaluated with respect to their binding affinity and signaling potency on human eosinophils.

Production of reactive oxygen intermediates by human macrophages exposed to soot particles and asbestos fibers and increase in NF-kappa B p50/p105 mRNA.

Alveolar macrophages (AM) play a decisive role in the immunologic defense system of the lung and in inflammatory pulmonary pathomechanisms. AM and blood monocytes (BM) were exposed to chrysotile B, soot FR 101, and Printex 90 (P 90). We evaluated the reactive oxygen intermediate (ROI) release of AM and BM after particle exposure.

The biologic role of interleukin-8: functional analysis and expression of CXCR1 and CXCR2 on human eosinophils.

Chemokines play an important role in attracting granulocytes into sites of inflammation. Two chemokine subfamilies differ in their biologic activity for different granulocyte subsets. Whereas CXC chemokines such as interleukin-8 (IL-8) activate predominantly neutrophils, CC chemokines such as RANTES and eotaxin activate predominantly eosinophils.

Indoor air pollutants stimulate interleukin-8-specific mRNA expression and protein secretion of alveolar macrophages.

Indoor air pollutants may cause inflammatory changes of the airways and adjacent pulmonary tissue. After phagocytosis of inhaled particles alveolar macrophages (AM) release chemotactic mediators capable of attracting inflammatory cells into the lung tissue. To evaluate these mechanisms further peripheral blood mononuclear cells (PBMNC) and human AM (freshly recovered from the lower respiratory tract) were exposed to the indoor particles Soot FR 101 and Printex 90, the asbestos fiber Chrysotile B, and titanium dioxide (TiO2) at concentrations of 10 or 50 microg/10(6) cells for up to 8 h.

In vitro study of human alveolar macrophages inflammatory mediator transcriptions and releases induced by soot FR 101, Printex 90, titandioxide and Chrysotile B.

Soot FR 101, Printex 90 and Chrysotile B are frequently found in indoor air pollutants phagocytized by alveolar macrophages (AM) involved in inflammatory pulmonary processes as, e.g. in cytokine secretions.