Purinergic system plays an important role in functional regulation of immune system. Extracellular ATP belongs to non-infectious danger signals (DAMP), has a pro-inflammatory effect and modulates the immune response. The end product of ATP breakdown, adenosine, plays an important role in limiting the inflammatory response. The activity of ectonucleotidase CD39 and CD73 supports the balance of ATP and adenosine at the site of inflammation. CD39 and CD73 expression is characterized by high variability. From the literature data, appropriate studies were carried out either in transgenic mice, or with adult healthy donors. The number of cells expressing CD39 and CD73 in T lymphocyte populations has not been evaluated in healthy children. Hence, our aim was to study the features of CD39 and CD73 expression in various subpopulations of CD4+ lymphocytes in apparently healthy children of different ages. We examined 45 healthy children aged 3.7 to 17.5 years (Me (Q0.25-Q0.75) 12.4 (10-16.1). The numbers of CD4+ cells, regulatory T lymphocytes (Treg CD4+CD25highCD127low), activated T helpers (Tact CD4+CD25+CD127high), and Th17 lymphocytes (CD4+CD161+CD3+) expressing CD39 and CD73 were evaluated by the flow cytometry. The number of cells expressing CD39 and CD73 depends on specific cell subpopulation. The highest content of CD39+ cells was observed in Tregs, and maximal amounts of CD73+ cells were found among Tact subset. In the Th17 lymphocyte subpopulation, there was no significant difference between the number of cells expressing CD39 and CD73. E have also shown an increase in the relative number of Th17 cells expressing CD73, along with age-dependent decrease in the relative number of Tact cells expressing CD39. An age-dependent decrease in absolute values with age was revealed for Treg, CD39+Treg, CD73+Treg, CD39+Th17, thus being consistent with age-related decrease in absolute numbers of lymphocytes and CD4+ cells. The obtained data concerning specific pattern of ectonucleotidases expression in functionally different populations of CD4+ lymphocytes should be taken into account when studying children with immune-mediated diseases from different age groups.

Introduction. The article assessed the effectiveness of decimeter wave therapy (DWT) in the postoperative period after laparoscopic appendectomy for destructive appendicitis in children. Authors relate positive clinical effects with the activation of mitochondrial energy metabolism. Material and methods. The study included 132 patients (46 destructive appendicitis cases, 86 h appendicular peritonitis patients). Among them, there were 75 (56.8 percent) boys and 57 (43.2 percent) girls aged of from 3 to 17 years (mean age of 10.7 ± 3.07 years). Patients of the main group received DWT procedures with the use of the apparatus DMV-02 “Solnyshko” starting from the 1st day after the surgery. Patients from the reference group received no physiotherapy treatment. The activity of dehydrogenases of lymphocytes (succinic dehydrogenase (SDH) and NADH-dehydrogenase) in patients from the main group and the comparison group were determined by means of cytomorphological method with the use a hardware-software visualization complex “Videotest” and the “Morphology 5.2” (Russia), at the 1st, 3rd and 5th day of the postoperative period. Results. Under the influence of DWT in the postoperative period the frequency of intestinal insufficiency syndrome, systemic inflammatory response syndrome, infiltrative adhesions was established to decline. There was noted a gain in the activity of mitochondrial enzymes, reflecting the first and second stages of the respiratory chain (SDH and NADH-dehydrogenase). In children with destructive appendicitis against the background of DWT, the normalization of the activity of LDH in moderate activation of NADH-dehydrogenase, and in appendicular peritonitis cases - the significant elevation in LDH activity of lymphocytes and activation of NADH-dehydrogenase occurs. In patients from the main group, the absolute number of peripheral blood lymphocytes normalized Conclusion. Under the influence of DWT there was noted the activation of enzymes of mitochondria that provides a mild course of the postoperative period.

Alterations in intracellular signaling pathways affecting immune cell activation, proliferation and differentiation of keratinocytes in psoriasis could explain the complex pathogenesis of the disease. NF-κB is one of the intracellular signaling pathways, which is involved in regulation of numerous pro-inflammatory genes, and affects the synthesis of pro-inflammatory cytokines directly involved in the development of psoriasis. The study was aimed to assess the number of cells with NF-κB translocation in lymphocyte populations of children with psoriasis depending in the disease severity and therapy. A total of 130 children with psoriasis vulgaris were examined. The comparison group included 30 healthy children. The study was conducted using the imaging flow cytometry Amnis ImageStreamX system. It was found that there were significant differences in the number of cells with NF-κB translocation in the lymphocyte populations of both children with psoriasis and comparison group. Children with psoriasis had a higher number of cells with NF-κB translocation in the populations of T helper cells, Tact, Treg, and Th17 compared to healthy children (p < 0.05). The number of cells with NF-κB translocation in children with psoriasis correlated with the disease severity PASI (Rmul = 0.32) and BSA (Rmul = 0.31) scores, as well as with the disease duration (p < 0.05). NF-κB determination could be considered an additional criterion for the disease severity assessment in children with psoriasis. The differences in the degree of reduction of the number of cells with NF-κB translocation 24 h after administration of biologics (adalimumab, etanercept, ustekinumab) have been shown. Studying NF-κB in cell populations offers the prospect of understanding pathogenetic mechanisms of inflammation and developing new therapeutic methods for psoriasis.

Frequent resulting disability and case mortality support the urgency of investigation of the immune response mechanisms triggered by severe injury (SI) in children. This study aimed to determine the informative immunological criteria of traumatic injury severity and prognosis in children (n = 43) based on the assessment of expression of CD39 and CD73 ectonucleotidase in populations of regulatory T cells (Treg, CD4+CD127lowCD25high) and T-helper 17 cells (Th17, CD4+CD161+CD3+) in SI cases grouped by the outcome (favorable (SIfav, n = 24), unfavorable (SIunfav, n = 17) and lethal (n = 2)). With the help of flow cytometry, we identified a pronounced decrease in the absolute number of Treg and Th17, as well as Treg and Th17 expressing CD39 and CD73, in the early post-traumatic period. In the SIfav and SIunfav groups the relative number of Treg and Th17 cells expressing CD39 differed significantly (p <0.05); it was substantially higher form the first to the third day post injury in the SIunfav group. The level of Treg CD39 (44.4%) is a premise for an unfavorable outcome in children surviving an SI. In fatality cases, we registered extremely low ectonucleotidase expression rates: CD39+Treg — 9.52% (9.52–13.75) and CD39+Th17 — 0.92% (0.74–1.1). In the SIunfav group, the intensity of fluorescence (FL) of CD39 on Treg cells in the early post-traumatic period was higher than seen in the SIfav group. The threshold value for the average fluorescence intensity (FL) of CD39 on Treg was 8.25 c.u. In fatality cases, the Treg CD39 FL values were extremely low: 3.95 c.u. (3.7–4.67). The results of the study indicate that in children, the expression of CD39 and CD73 in Treg and Th17 populations is significantly associated with the severity of injury and outcome of the traumatic disease.

The regulation of TNF inhibitor therapy-associated immune responses in inflammatory bowel diseases (IBD) in children remains an urgent problem. The study aimed at analyzing the expression of CD39/CD73 endonucleotidases by different subsets of peripheral blood T cells in children with IBD including Crohn's disease (n = 34) and ulcerative colitis (n = 33) having received TNF inhibitors in comparison with conditionally healthy children (n = 45). Lymphocyte subsets including regulatory T cells (Treg, CD4+CD127lowCD25high), activated T cells (Tact, CD4+CD25+CD127high) and Th17 cells (CD4+CD161+CD3+) were studied by flow cytometry. The results are presented as medians (Me) and quartiles (Q25–Q75). In children with IBD the highest and the lowest relative counts of CD39+ cells were found in Treg and Tact subsets — 31% (15–38) and 4% (1–7), respectively. The highest relative counts of CD73+ cells were found in Tact — 13% (8–21). The CD39 and CD73 expression ratio in patients with IBD, and in the control group as well, depended on particular subset. CD39 expression in Treg, Tact and Th17 of patients with IBD was not age-dependent. Patients with acute Crohn's disease revealed decreased expression of CD39 in Treg compared with the control group (12% (9–23) vs 35% (28–39), respectively; р = 10–6). Patients with Crohn's disease in remission revealed increased expression of CD39 in Treg compared with the acute of the disease (31% (27–40) vs 12% (9–23); р = 9.4 × 10–5). Patients with Crohn's disease in remission revealed no significant differences with the control group apart from reduced expression of CD73 by Treg in Crohn's disease. The results indicate significant association of CD39 and CD73 expression levels in particular subsets of CD4+ cells with the phase of the disease (acute vs remission) and, accordingly, with the anti-TNF regimen efficacy.