The present knowledge of the inflammatory process and the inflammatory mediators

Area of Science:

• Immunology
• Cell Biology
• Pathology

Background:

• Acute inflammatory arthritis involves endothelial damage, synovial edema, and polymorphonuclear cell (PMN) invasion.
• Early inflammatory events are driven by complex interactions between PMNs and activated endothelial cells.
• Adhesion molecules on PMNs and endothelium mediate PMN adhesion and migration to inflammatory sites.

Purpose of the Study:

• To elucidate the mechanisms of PMN-endothelial cell interactions in inflammatory arthritis.
• To investigate the role of specific adhesion molecules in PMN recruitment.
• To examine PMN function in the pathogenesis of seronegative spondyloarthropathies.

Main Methods:

• Analysis of endothelial damage, synovial edema, and cellular infiltration.
• Investigation of adhesion molecule expression and function (L-selectin, beta 2-integrins, E-selectin, ICAM-1, ICAM-2).
• Assessment of PMN chemotaxis and production of oxygen-derived free radicals.

Main Results:

• PMN adhesion to endothelium is mediated by L-selectin, beta 2-integrins, and their counter receptors.
• Endothelial cells are activated by inflammatory mediators (TNF, IL-1, LPS) to express adhesion molecules and chemokines (IL-8).
• Aberrant PMN function, characterized by enhanced chemotaxis and high free radical production, was observed in seronegative spondyloarthropathies.

Conclusions:

• PMN-endothelial cell interactions are critical in initiating and perpetuating inflammatory arthritis.
• Specific adhesion molecules and inflammatory mediators orchestrate PMN recruitment.
• Dysfunctional PMN behavior contributes significantly to the pathogenesis of seronegative spondyloarthropathies.