RESUMEN
Interleukin 1 (IL-1), present in high amounts in normal human skin without any sign of inflammation, suggests a complex mechanism by which its bioactivity is regulated. The specific receptor antagonist of IL-1 (IL-1ra) was analyzed in human skin, sweat and cultured keratinocytes. Extracts of both skin and cultured keratinocytes blocked the binding of [125I]IL-1 to its receptor whereas sweat did not. The inhibitory activity was cell-associated, was not secreted by cultured keratinocytes, and IL-1ra mRNA was identified in these cells. There was an inverse relationship between the level of IL-1ra and that of IL-1 alpha and beta since extracts of differentiating keratinocytes (DK) and higher IL-1ra levels and expressed more mRNA for IL-1ra than non-differentiated keratinocytes (NDK), whereas NDK contained 4 times more IL-1 alpha and beta proteins than DK. This association of cell differentiation with a shift in agonist/antagonist ratio might be related to important autocrine or paracrine functions of IL-1 in normal and inflamed human skin.
Asunto(s)
Epidermis/fisiología , Interleucina-1/análisis , Queratinocitos/fisiología , Proteínas/análisis , Sialoglicoproteínas , Northern Blotting , Línea Celular , Células Cultivadas , Epidermis/química , Humanos , Proteína Antagonista del Receptor de Interleucina 1 , Interleucina-1/metabolismo , Queratinocitos/química , Cinética , Proteínas/genética , ARN/genética , ARN/aislamiento & purificación , Receptores Inmunológicos/metabolismo , Receptores de Interleucina-1 , Sudor/química , Sudor/fisiologíaRESUMEN
A Doppler broadening of x-ray transitions from pionic nitrogen and muonic oxygen, which is attributed to Coulomb explosion of the molecules, has been observed by using a crystal spectrometer. Large linewidths indicate fast ionization of the molecules and a charge of (3-4)e for the accelerated fragments.