Once upon a time, inflammation

Inflammation has accompanied humans since their first ancestors appeared on Earth. Aulus Cornelius Celsus (25 BC-50 AD), a Roman encyclopedist, offered a still valid statement about inflammation: "Notae vero inflammationis sunt quatuor: rubor et tumor cum calore and dolore", defining the four cardinal signs of inflammation as redness and swelling with heat and pain. While inflammation has long been considered as a morbid phenomenon, John Hunter (18th century) and Elie Metchnikoff (19th century) understood that it was a natural and beneficial event that aims to address a sterile or an infectious insult. Many other famous scientists and some forgotten ones have identified the different cellular and molecular players, and deciphered the different mechanisms of inflammation. This review pays tribute to some of the giants who made major contributions, from Hippocrates to the late 19th and first half of the 20th century. We particularly address the discoveries related to phagocytes, diapedesis, chemotactism, and fever. We also mention the findings of the various inflammatory mediators and the different approaches designed to treat inflammatory disorders.(AU)

Polymorphonuclear leukocyte migration across intestinal epithelium induces epithelial cytokine expression

La migración de neutrófilos polimorfonucleares es un rasgo común de la inflamación activa, que precede la formación de abscesos. La contribución relativa de células epiteliales como fuente de quimioquinas en la infiltración de leucocitos durante la inflamación intestinal no ha sido estudiada. Para evaluar esta contribución nosotros diseñamos un modelo heterólogo de migración transepitelial, “in vitro”, haciendo uso de PMN de rata y células epiteliales de origen humano. Nosotros demostramos que neutrófilos polimorfonucleares luego de su activación quimiotáctica, inducen el incremento en los niveles de ARNm de IL-1ß, IL-8 en las células epiteliales de intestino, mientras que no afecta al ARNm de ENA-78. Estos resultados sugieren que quimiocinas y citoquinas sintetizados por la célula epitelial podrían jugar un papel en el mantenimiento de la respuesta inflamatoria.

Polymorphonuclear neutrophil migration is a common feature of active inflammation that precedes the formation of abscesses. The relative contribution of epithelial cells as a source of chemokines in the recruitment of leukocytes during intestinal inflammation has not been studied. To evaluate this contribution, we have designed a heterologous “in vitro” model for transepithelial PMN migration, based on the use of rat neutrophils and human epithelial cells. We show that polymorphonuclear neutrophil, upon chemotactic activation, induces an increase in IL-1ß, IL-8 levels in intestinal epithelial cells, while not changed ENA-78 mRNA. These results suggest that chemokines and cytokines synthesized by intestinal epithelial cells could play a role in the maintenance of the inflammatory response.