Regulation of the target protein (transgene) expression in the adenovirus vector using agonists of toll-like receptors.

Replication-defective adenoviral vectors are effective molecular tools for both gene therapy and gene vaccination. Using such vectors one can deliver and express target genes in different epithelial, liver, hematopoietic and immune system cells of animal and human origin. The success of gene therapy and gene vaccination depends on the production intensity of the target protein encoded by the transgene. In this work, we studied influence of Toll-like receptors (TLR) agonists on transduction and expression efficacy of adenoviral vectors in animal and human antigen-presenting cells. We found that agonists of TLR2, 4, 5, 7, 8 and 9 significantly enhance a production of the target protein in cells transduced with adenoviral vector having the target gene insert. The enhancement was observed in dendritic cells and macrophages expressing cytoplasmic (GFP), membrane (HA) or secretory (SEAP) proteins encoded by the respective rAd-vectors. Experiments in mice showed that enhancement of the transgene expression can be achieved in the organism of animals using a pharmaceutical-grade TLR4-agonist. In contrast to other TLR-agonists, the agonist of TLR3 substantially suppressed the expression of transgene in cells transduced with adenoviral vectors having insert of GFP or SEAP target genes. We propose that the enhancement of transgene expression is linked to the activation of MyD88→ NF-kB, while the inhibition of transgene expression depends on TRIF→ IRF signaling pathways. Both of these pathways jointly exploited by TLR4-agonists lead to the enhancement of transgene expression due to the dominant role of the MyD88→ NF-kB signaling.

[Psoralen-photosensitized formation of free lipid radicals at 77 degrees K]. / Fotosensibilizirovannoe psoralenami obrazovanie svobodnykh radikalov lipidov pri 77 K.

It is shown by ESR method that 8-methoxypsoralen (8-MOP) under low temperature UV-irradiation has no influence on free radical formation of saturated fatty acids (FA). Under the same conditions the quantum yield of free radical photogeneration for unsaturated FA (oleate and limolenate) after addition of 8-MOP increased 7.5-15 times. The ESR spectrum of free radicals generated after interaction of 8-MOP with polyunsaturated FA, may be presented as superposition of signals-CH-(CH = CH)2-, -CH2CHCH2- and -CH2CH2. The molecular mechanism of photosensitized reactions is discussed.