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DNA fragments containing genes for coding IFN-gamma-binding proteins (IFNgammaBPs) of variola virus (VARV) and monkeypox virus (MPXV) were obtained from viral genomes using PCR. Isolated genes coding desired proteins were expressed in the insect Sf21 cells using baculovirus expression system. Secreted recombinant IFNgammaBPs were isolated from culture medium of infected Sf21 cells through affinity chromatography procedure. SDS-PAAG and Western blot analysis of culture medium of infected insect cells and preparations of purified recombinant IFNgammaBPs indicated that recombinant viral proteins were dimerized even in the absence of ligand (hIFNgamma) unlike their cell (eucaryotic) analogs. Biological activity of the recombinant IFNgammaBPs were studied in the test of protective effect inhibition of hIFNgamma on L68 cells infected with murine encephalomyocarditis virus. It was shown that recombinant IFNgammaBPs had dose-dependent IFNgamma-inhibiting activity. A possibility of the elaboration of new therapeutics for anti-hIFNgamma therapy on the base of IFNgammaBPs is discussed.

The synthetic chimeric gene TBI-HBS encoding the synthesis of immunogenic ENV and GAC epitopes of HIV-1 (immunogenes of T- and B-lymphocytes) and of the surface protein (HBsAg) of the hepatitis B virus was introduced into tomato plants var. Ventura by agrobacterial vector pBIN35TBI-HBS; transgenic tomato plants with the integrated gene TBI-HBS were generated. The integration of the TBI-HBS target gene was confirmed by PCR. The synthesis of antigenic proteins of TBI and HBsAg in fruits of transgenic tomato plants was displayed by immunoassay. The fruits of transgenic tomato plants were fed to experimental mice with a 1-week interval. On days 14 and 28, there was discovered a sufficiently high content of antibodies to the antigenic proteins of HBV and HIV-1 in serum of experimental animals. Antibodies were found in feces of experimental mice; no antibodies were found in the control group of mice. Hence, it was established that the TBI (HIV-1) and HBsAg (HBV) antigens were synthesized in transgenic tomato fruits due to the integrated construction of pBINNp35TBI-HBS in an amount that was enough to induce the immunogenic response in mice to the oral delivery of edible vaccine.

Sequencing and computer analysis of the variola major virus strain India-1967 (VAR-IND) genome segment (53,018 bp) from the right terminal region have been carried out. Fifty nine potential open reading frames (ORFs) of over 60 amino acid residues have been identified. Structure-function organization of VAR-IND DNA segment under study was compared with the previously reported sequences from the analogous genomic regions of vaccinia virus strains Copenhagen (VAC-COP) and Western Reserve (VAC-WR) and variola virus strain Harvey (VAR-HAR). Multiple distinctions in the genetic map of VAR-IND from VAC-COP and VAC-WR have been revealed along with the high similarity to the corresponding VAR-HAR segment. Possible functions of the predicted viral proteins and the effect of their differences on the features of orthopoxviruses are discussed.

Chemical-enzymatic synthesis and cloning of a gene for a human anaphylatoxin C5a analog were carried out. Recombinant plasmid pRC5a providing the expression of the synthetic gene in the Escherichia coli cells was obtained. The biological activity of the expression product was demonstrated by the chemotaxis activity test and by the release of myeloperoxidases from rat peritoneal cells that was induced by bacterial cell lysates containing the recombinant protein.

Differential regulation of the expression of various families of the rat genome interspersed repetitive sequences by glucocorticoid hormones in liver has been demonstrated. Small ID-like RNA complementarily associated with high-molecular-weight cytoplasmic poly(A)-containing RNAs has been identified. The results obtained indicate that glucocorticoids hormones induce expression of the B2, ID, and L1 families in rat liver. The content of the transcripts of these repetitive elements is increased by the hormones in the molecules of heterogeneous nuclear RNA. In the molecules of high-molecular-mass poly(A)-containing cytoplasmic RNA glucocorticoids increase the content of the ID-homologous sequences. In the population of the small specific RNA the content of the ID-homologous transcripts is also increased. A suggestion is put forward about the involvement of the ID-like element in the hormonal posttranscriptional regulation of gene expression at the mRNA level.

Recombinant plasmids providing the synthesis of chimeric proteins consisting of amino acid sequences of human interleukin-2 (IL-2) and Shiga toxin cytotoxic A-subunit (ILA and AIL chimeric toxins) were constructed. The ILA and AIL chimeric toxins were shown to inhibit protein synthesis in the rabbit reticulocytes cell-free system. These chimeric toxins displayed two opposite activities of the constituent parts of their molecules on T-lymphocytes from the peripheral blood of healthy volunteers. Hybrid protein AIL (approximately 10(-6) g/ml) has caused the most significant depression of T-lymphoblast proliferation.

Expression of pro-opiomelanocortin (POMC) gene in pituitary of rats from newly developed hypertensive strain (ISIAH strain) was studied by dot hybridization. The pUC8 plasmid containing 900 base pair (bp) segment or the human POMC gene corresponding to the major portion of the 3'-nontranslated mRNA region and 60 bp coding for the signal peptide, was used as a probe for hybridization. It was found that the expression of the POMC in pituitary of the hypertensive JSJAH rats was more than 3-fold gene lower as compared to normotensive Wistar strain. The latter is the original strain from which the ISIAH rats were bred. The mechanism of this phenomenon and its possible relation to the arterial hypertension are discussed.

Artificial DNA fragments encoding human interleukin-2 (133 a.a.) and its analogue (deletion of 14 C-terminal a.a.) were prepared by means of the DNA polymerase I mediated extension of synthetic polynucleotides having short overlapping sequences at their 3'-ends. The fragments were cloned in specially designed pFH-type plasmids and then excised by the FokI and other restriction endonucleases to yield the subfragments with the structurally predetermined 5'-unique cohesive ends. The complete synthetic gene was constructed by one or two-step ligation. The expressed IL-2 was tested by analysing the T-cell proliferation activity of E.coli crude lisates containing the pEXIL2 expression plasmid.

Chemical-enzymatic synthesis and cloning of the DNA fragment coding for the human interleukin-2 signal sequence was accomplished. A hybrid plasmid pSIL-2 containing the gene of the human interleukin-2 with this signal sequence was constructed for effective expression of the gene in eukaryotic systems. A variant permitting the removal of the interleukin-2 stop-codons was obtained, which is suitable for the construction of chimeric genes containing the interleukin-2 gene sequence at the 5'-end.