Effects of Kagocel^® on the Counts of Multipotent Stromal Cells, Expression of Cytokine Genes in Primary Cultures of Bone Marrow Stromal Cells, and Serum Cytokine Concentrations in CBA Mice

The efficiency of cloning of bone marrow multipotent stromal cells (ECF-MSC) from CBA mice and the MSC counts in the femoral bone increased 24 h after a single in vivo (but not in vitro) injection of kagocel (active substance of antiviral drug Kagocel^®) 1.4 times (in response to 50-80 μg) and 4.6 times (in response to 250 μg). The maximum increase of ECF-MSC in response to 50 μg per mouse was detected just 1 h after Kagocel injection to intact mice and to mice previously receiving the drug for 3 days (2 and 1.7 times, respectively). The increase of ECF-MSC was 3-fold less intense in response to oral Kagocel in a dose of 250 μg/mouse vs. intraperitoneal Kagocel, ECF-MSC corresponding to its level in response to oral Poly (I:C). In vivo Kagocel led to emergence of proinflammatory cytokine IFN-γ, IL-1β, and IL-8 mRNA in primary cultures of bone marrow stromal cells. Serum concentrations of IL-2, IL-5, IL-10, GM-CSF, IFN-γ, TNF-α, IL-4, and IL-12 increased 1.5 and 2 times just 1 h after Kagocel injection in doses of 30-50 and 250 μg, respectively, to intact mice and to animals previously treated with the drug for 3 days. The cytokine concentrations normalized after 3 h and increased again after 24 h, though did not reach the levels recorded 1 h after the drug injection. These data indicated that the therapeutic and preventive effects of Kagocel, together with its previously demonstrated stimulation of α- and β-interferon production during several days, could be due to the capacity of this drug to increase the bone marrow ECF-MSC, serum cytokine concentrations, and induce the expression of proinflammatory cytokine genes in the bone marrow stromal cells 1 h after its injection.