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Scent signals play an important role in the life of rodents. The scent of the opposite sex can modulate immunity. In mice populations with natural specific pathogens, in males, the scent of a female leads to a redistribution of leukocytes between the lung and the blood, resistance to the influenza virus, and a decrease in antibody production, but not in the development of inflammation induced by bacterial endotoxins. This study demonstrates the effect of the scent of soiled bedding of specific pathogen-free (SPF) status female mice on the percentage of different types of leukocytes in the blood, the expression of Nos2 , Arg1 , and Foxp3 genes, and the presence of M1/M2 macrophages in the lungs of male BALB/c mice. The scent of the female SPF mice caused a redistribution between T- and B-cells in the blood, the increase in the expression of Nos2 , Arg1 genes, and the percentage of M1 type macrophages in the lung, but did not affect the different types of T-cells in the periphery or the lungs. Activation of macrophages in the lung is part of mucosal immunity, which is necessary for males as an adaptive mechanism to prevent potential infection during the search for a sexual partner.

Intestinal mucus protects epithelial and immune cells from the gut resident microorganisms, and provides growth-promoting factors as mucus-derived O-glycans for beneficial bacteria. A lack of intestinal protective mucus results in changes in the commensal microflora composition, mucosal immune system reprogramming, and inflammation. Previous work has shown that fucose, the terminal glycan chain component of the intestinal glycoprotein Mucin2, and fucoidan polysaccharides have an anti-inflammatory effect in some mouse models of colitis. This study evaluates the effect of fucose on reproductive performance in heterozygous mutant Muc2 female mice. We found that even though Muc2 +/- females are physiologically indistinguishable from C57Bl/6 mice, they have a significantly reduced reproductive performance upon dietary fucose supplementation. Metagenomic analysis reveals that the otherwise healthy wild-type siblings of Muc2 -/- animals have reduced numbers of some of the intestinal commensal bacterial species, compared to C57BL/6 mice. We propose that the changes in beneficial microflora affect the immune status in Muc2 +/- mice, which causes implantation impairment. In accordance with this hypothesis, we find that macrophage polarization during pregnancy is impaired in Muc2 +/- females upon addition of fucose. Metabolic profiling of peritoneal macrophages from Muc2 +/- females reveals their predisposition towards anaerobic glycolysis in favor of oxidative phosphorylation, compared to C57BL/6-derived cells. In vitro experiments on phagocytosis activity and mitochondrial respiration suggest that fucose affects oxidative phosphorylation in a genotype-specific manner, which might interfere with implantation depending on the initial status of macrophages. This hypothesis is further confirmed in BALB/c female mice, where fucose caused pregnancy loss and opposed implantation-associated M2 macrophage polarization. Taken together, these data suggest that intestinal microflora affects host immunity and pregnancy outcome. At the same time, dietary fucose might act as a differential regulator of macrophage polarization during implantation, depending on the immune status of the host.

We designed a multimeric nuclease-resistant 63-bp trimeric small-interfering RNA (tsiRNA) comprising in one duplex the sequence of siRNAs targeting mRNAs of MDR1, LMP2, and LMP7 genes. We show that such tsiRNA is able to suppress the expression of all the target genes independently and with high efficiency, acting via a Dicer-dependent mechanism. tsiRNA is diced into 42- and 21-bp duplexes inside the cell. tsiRNA-induced gene silencing is characterized by kinetics similar to that of canonical siRNA, while the silencing efficiency is significantly higher than that of canonical siRNA with the same sequence., (© 2017 Federation of European Biochemical Societies.)

Overexpression of inducible subunits of immunoproteasome is related to pathogenesis of some chronic diseases. Specific inhibition of the immunosubunits may be used for the treatment of these diseases and RNA interference is one of the potent methods used in this area. We designed 2'-O-methyl modified siRNAs with selectively protected nuclease-sensitive sites, which efficiently silence LMP2, LMP7, and MECL-1 genes expression. To provide stable long-lasting inhibition of target genes, short-hairpin RNAs (shRNA) expressed by lentiviral vectors were constructed. Our results demonstrated that chemically modified siRNAs inhibited the expression of target genes with similar efficiency or with efficiency exceeding that of corresponding shRNAs and provide silencing effect for 5 days.

The pathogenesis of autoimmune and neurodegenerative diseases involves overexpression of inducible subunits of the immunoproteasome. However, the clinical application of inhibitors to inducible subunits of the immunoproteasome has been limited due to systemic toxicity. Here, we designed siRNAs that efficiently silence LMP2, LMP7 and MECL-1 gene expression. Inducible subunits of the immunoproteasome are complex siRNA targets because they have a long half-life; therefore, we introduced 2'-O-methyl modifications into nuclease-sensitive sites. This led to 90-95% silencing efficiency and prolonged silencing, eliminating the need for multiple transfections. Furthermore, we showed that in the absence of transfection reagent, siRNAs with lipophilic residues were able to penetrate cells more effectively and decrease the expression of inducible immunoproteasome subunits by 35% after 5 days. These results show that siRNA targeted to inducible immunoproteasome subunits have great potential for the development of novel therapeutics for autoimmune and neurodegenerative diseases., (Copyright © 2016 Elsevier B.V. and Société française de biochimie et biologie Moléculaire (SFBBM). All rights reserved.)

DsRNAs longer than 30bp induce interferon response and global changes in gene expression profile in mammalians. 21bp siRNA and 25/27bp dsiRNA acting via RNA interference mechanism are used for specific gene silencing in this class of organisms. We designed selectively 2'-O-methyl-modified 42 and 63bp anti-MDR1-siRNAs that silence the expression of P-glycoprotein and restore the sensitivity of drug-resistant cancer cells to cytostatic more efficiently than canonical 21bp siRNAs. We also show that they act in a Dicer-independent mode and are devoid of immunostimulating properties. Our findings suggest that 42 and 63bp siRNAs could be used as potential therapeutics., (Copyright © 2014 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.)

Objective: Platelets can modulate lymphocytes' role in the pathophysiology of thyroid autoimmune diseases. The present study was performed to clarify the status of platelet-lymphocyte subpopulations aggregation in circulating blood in patients with Graves' disease (GD)., Methods: One hundred and fifty patients with GD (GD group) and 45 hyperthyroid patients with toxic multinodular goiter (TMG group) were recruited in the study. Control group consisted 150 healthy subjects. Immunophenotyping of lymphocytes was performed by flow cytometry. Detection of lymphocyte-platelet aggregates (LPAs) was done using light microscope after Ficoll-gradient centrifugation., Results: The group of GD patients exhibited reduced CD8 lymphocyte and higher CD19 cell counts compared with TMG group and healthy controls. A greater number of activated CD3, HLA-DR+ lymphocytes were observed in GD than in TMG group and control group. GD group was characterized by lower blood platelet count (232 ± 89 × 10 cells/µL) than TMG group (251 ± 97 × 10 cells/µL; P < 0.05) and control group (262 ± 95 × 10 cells/µL; P < 0.05). In GD group, more platelet-bound lymphocytes (332 ± 91 /µL) were found than that in TMG group (116 ± 67/µL, P < 0.005) and control group (104 ± 58 /µL; P < 0.001)., Conclusions: GD is associated with higher levels of activated lymphocytes and lymphocyte-platelet aggregates.