Differential production of interleukin 1 on the surface of biomaterials.

The production of cytokines on the surface of surgical biomaterials plays a major role in their biocompatibility. Membrane-associated interleukin 1 (mIL-1) is a cytokine found on the surface of macrophages activated by biomaterials. To better understand the host-foreign body interaction, we quantitated the production of mIL-1 on the surface of two materials commonly used in surgery, expanded polytef (ePTFE) and silicon elastomer (SE). The mean (+/- SD) level of mIL-1 produced by adherent cells to ePTFE significantly decreased from day 2 (13,746 +/- 3630 cpm per disk) compared with day 7 (2828 +/- 1304 cpm per disk). However, the level of mIL-1 produced by ePTFE-adherent cells was still markedly greater than the level of mIL-1 produced by cells adherent to SE (1877 +/- 1028 vs 1595 +/- 822 cpm per disk). These results indicate that ePTFE and SE elicit a differential host response in terms of cytokine production. This study may enhance our understanding of the cellular events on the surface of biomaterials that underlie clinical observations.