Interleukin-1 receptor antagonist (IL-1Ra) and vaccinia virus protein C10L share a VTXFYF motif, with X being Lys or Arg residue, respectively. Peptides of such sequence compete successfully with IL-1 for the cellular receptor. A pair of complementary peptides, based on the Siemion's hypothesis on the periodicity of the genetic code (QWLNIN and QWANIN), and another pair, in which, following the Root- Bernstein theory, Lys was used as complementary amino acid to Phe (QWLKIK and QWAKIK), were investigated for the peptide-antipeptide interactions using mass spectrometry (ESI-MS) and circular dichroism (CD) methods. The CD measurements indicated some conformational changes, more pronounced in the Siemion's pairs, however, no heterodimer formation was found by MS. In the region of IL-1 receptor situated close to the position of IL-1Ra in the IL-1Ra-receptor complex, a KQKL motif is present, suggesting a possibility of complementary recognition of the Root-Bernstein type in the IL-1 receptor. The biological activity of the complementary peptides is similar to that of the original ones. They efficiently compete with IL-1 and show moderate immunosuppressory activity in humoral and cellular immune response. The inhibition of the IL-1-IL-1 receptor interaction may result from the complementary peptides acting as mini-receptors with affinity for IL-1.
We report here that human astrocytoma cell line U373-MG is able to express genes of the following components of plasminogen activation system:PAI-1,PN-1,u-PA and t-PA. Treatment of these cells with IL-1 ß results in accumulation of PAI-1,PN-1 and u-PA mRNAs,whereas t-PA mRNA remains unaffected.IFN preferentially enhances PN-1 and PAI-1,EGF enhances PAI-1,u-PA and t-PA expression.Simultaneous addition of anti-inflammatory cytokines IL-4,IL-13 and IL-10 has little effect on the tested components,except induction of u-PA mRNA wich was further enhanced by IL-4.We have confirmed interesting time-dependent regulation of plasminogen activation system by EGF/IFN .Cells stimulated with EGF/IFN show at first increased proteolytic activity but after 24 h inhibition of proteolysis with PAI-1 would prevail.To understand the co- operative effect of EGF and IFN in PAI-1 induction the kinetics of activation of STAT1 was studied.It was found that although EGF alone does not activate STAT1,the STAT1 binding activity in the cells treated with the mixture of EGF/IFN was considerably prolonged.Our results indicate the importance of inflammatory cytokines and EGF in gene regulation of plasminogen activation system in astrocytoma cells.
Literature data indicate an association between the presence of Helicobacter spp. in the liver and the development of hepatocellular carcinoma (HCC). However, the role of H. pylori infections in chronic liver diseases (CLD) remains controversial. The aim of this study was to detect Helicobacter spp. DNA in patients with CLD, and to investigate the host response to the presence of the bacterium in the liver. Helicobacter spp. DNA was detected in 59% samples. H.pylori was the most prevalent species (94%). We estimated the expression level of IL-1 and IL-8 genes. The presence of Helicobacter spp. did not have a significant effect on the gene expression of IL-8 and IL-1.