The essence of autoimmune thyroid disease (AITD) is loss of tolerance of own tissues caused by malfunction of T lymphocytes, which affects the production of antibodies reacting with particular cell structures and tissues. Foxp3⁺ regulatory T cells (Tregs) take part in the regulation of immune response and play a leading role in developing immune tolerance through active suppression. The aim of the study was to estimate the expression of CD4+CD25^high, CD4+CD25+CD127^lowFoxP3⁺ and CD4+ FoxP3 T cells in patients with Graves' disease (GD) (n = 24, median age 15.5 years), in patients with Hashimoto's thyroiditis (HT) (n = 30, median age 15 years) in comparison with sex- and age-matched healthy control subjects (n = 30, median age 15 years). Polychromatic flow cytometry using a FACSCalibur (BD Biosciences) cytometer was applied to delineate T regulatory cell populations. In untreated patients with Graves' disease and HT we observed a significant decrease in CD4+FoxP3 (p < 0.001, p < 0.01) and CD4+CD25^high (p < 0.016, p < 0.048) T lymphocytes as compared to the healthy control subjects. After 6–12 months of L-thyroxine therapy in HT cases these phenotypes of Tregs were normalized, yet no such changes were observed during GD therapy. The analysis of CD4+CD25+CD127^lowFoxP3⁺T cells in the peripheral blood revealed comparable percentages of these cells in patients with thyroid autoimmune diseases to the controls. We conclude that the reduction number of Tregs with CD4+CD25^high and CD4+FoxP3 phenotype suggests their role in initiation and development of autoimmune process in thyroid disorders.

The aim of this study was to evaluate platelet activation in gastric cancer patients with regard to histopathological classification and the presence of distant metastases, by using platelet morphological parameters: MPV, L-PLT, MPC, as well as quantitative evaluation of surface receptor expression: CD41a, CD61, CD42b, CD62P, by flow cytometry at the resting state and after TRAP activation. In gastric cancer patients higher values of MPV and LP, as well as decreased MPC values were determined. Quantitative evaluation of surface antigen expression also revealed higher number of CD41a, CD61 and CD62P molecules, as compared with the platelets in the control group. Significant decrease of CD42b molecules' number after TRAP incubation, and the increased CD41a, CD61 and CD62P expression also point to the retained reactivation capacity of platelets. Good correlation between morphological parameters and the number of CD62P molecules indicates the usefulness of routine tests in evaluation of platelet activation.

Mucoadhesive gelling systems based on chitosan and chitosan/β-glycerophosphate (β-GP) were developed in order to increase clotrimazole residence time in the vaginal cavity. Ex vivo mucoadhesiveness using porcine vaginal mucosa followed with mechanical, viscoelastic, and swelling properties of prepared hydrogels were evaluated. Drug-free, sterile, unmodified, and β-GP crosslinked chitosan were investigated for the in vitro cytotoxicity in CRL 2616 human vaginal mucosa cells using MTT assay, fluorescent microscopy, and flow cytometry analysis. Chitosan/β-GP hydrogels exhibited pseudoplastic and thixotropic properties. Ionic interaction between β-GP and chitosan improved mechanical properties of hydrogels in terms of hardness, cohesiveness, and compressibility. The hydrogels’ ability to interact with porcine vaginal mucosa (measured as force of detachment and work of adhesion) was comparable to those obtained with reference mucoadhesive gel Replens™. Surprisingly, greater mucoadhesive properties were noticed for chitosan/β-GP hydrogels. The cytotoxic effect of unmodified and β-GP crosslinked chitosan was hardly affected by chitosan molecular weight, exhibited mainly through inducing apoptosis, and was found to be significantly lower in the presence of chitosan/β-GP. Furthermore, the higher amount of β-GP was used to crosslink chitosan, the lower cytotoxic effect was observed.

Objective We evaluated blood concentrations of kynurenine pathway metabolites, natural and induced regulatory T cells (nTreg, iTreg), and Th17 cells in order to examine the activity of the kynurenine pathway and its relation to immune status in patients with pulmonary arterial hypertension (PAH). Methods Plasma concentrations of tryptophan, kynurenine, kynurenic acid, anthranilic acid, and 3-hydroxykynurenine were quantified in 26 patients with PAH (vs 30 healthy controls) at baseline and after 6 months, and assessed them in relation to clinical parameters, frequencies of lymphocyte subsets, and outcome. Results The PAH group presented higher concentrations of tryptophan (52.9 (IQR 46.3–57.5) vs 40.3 (35.2–46.3) µmol/L, p=0.00003), kynurenine 2.8 (2.4−3.4) vs 1.9 (1.5–2.3) µmol/L, p=0.000007), kynurenine/tryptophan ratio (0.051 (0.044–0.064) vs 0.043 (0.039–0.055), p=0.03), iTreg frequencies (10.5 (8.8–13.9)% vs 6.8 (5.2–9.5)%, p=0.002) and iTreg/Th17 (1.73 (1.2–2.8) vs 0.93 (0.61–1.27), p=0.003) together with lower ratios of kynurenic acid/kynurenine, 3-hydroxykynurenine/kynurenine, and anthranilic acid/kynurenine. Kynurenine concentrations and kynurenine/tryptophan ratio correlated positively with iTreg/Th17, and inversely with Th17 subsets, whereas kynurenic acid/kynurenine and anthranilic acid/kynurenine ratios correlated positively with Th17. Adverse outcomes occurred in 9 of 26 patients and they showed higher baseline concentrations of kynurenine (3.6 (2.8–4.3) vs 2.7 (2.1–3.2) µmol/L, p=0.033). Median kynurenine values ≥3.4 µmol/L (67% sensitivity, 94% specificity) identified patients with a worse clinical course. Conclusions PAH is characterised by upregulated tryptophan metabolism and enhanced biosynthesis of kynurenine. Elevated kynurenine concentration is associated with an adverse clinical course. Dysregulated immunity, delineated by Treg-Th17 imbalance, is directly related to diverse activation of the kynurenine pathway, indicating the potential interplay between kynurenines and the immune system in PAH.

Objective: The low number of circulating endothelial progenitor cells (EPCs) has emerged as a biomarker of cardiovascular (CV) risk in adults. Data regarding EPCs in paediatric populations with CV risk factors are limited. The aim of the study was to estimate the EPC number and its relationship with vascular function and structure in children with type 1 diabetes mellitus (T1DM).Design and methods: We performed a comparative analysis of 52 children with T1DM (mean age 14.5 years; diabetes duration, 6.0 years; HbA1c level, 8.5%) and 36 healthy age- and gender-matched control children. EPCs were identified and analysed by flow cytometry with the use of MABs directed against CD34, CD144 (VE-cadherin) and CD309 (VEGFR-2). sICAM-1, hsCRP, thrombomodulin and adiponectin levels were also assessed. We evaluated vascular function (flow-mediated dilation (FMD)) and structure (carotid intima–media thickness (IMT)) ultrasonographically.Results: Frequencies of CD34+ cells were similar in both groups (P=0.30). In contrast, frequencies of CD34+VE-cadherin+ cells were significantly higher in diabetic children compared with the healthy group (P=0.003). Similarly, diabetic patients tended to present with higher frequencies of CD34+VEGFR+ cells (P=0.06). FMD was lower (6.9 vs 10.5%, P=0.002) and IMT was higher (0.50 vs 0.44 mm, P=0.0006) in diabetic children. We demonstrated a significant relationship between CD34+VEGFR-2+ cells and BMI (r=0.3, P=0.014), HDL (r=−0.27, P=0.04), sICAM-1 (r=0.47, P=0.023) and FMD (r=−0.45, P<0.001). Similarly, frequencies of CD34+VE-cadherin+ cells were significantly correlated with BMI (r=0.32, P=0.02) and FMD (r=−0.31, P=0.03).Conclusions: We demonstrated here that increased frequencies of EPCs observed in diabetic children are negatively correlated with endothelial function. Further studies are warranted to assess whether this phenomenon might result from effective mobilisation of EPCs in order to repair damaged endothelium in children at increased risk for atherosclerosis.

Ovarian cancer (OC) is one of the deadliest gynecological cancers, largely due to the fast development of metastasis and drug resistance. The immune system is a critical component of the OC tumor microenvironment (TME) and immune cells such as T cells, NK cells, and dendritic cells (DC) play a key role in anti-tumor immunity. However, OC tumor cells are well known for evading immune surveillance by modulating the immune response through various mechanisms. Recruiting immune-suppressive cells such as regulatory T cells (Treg cells), macrophages, or myeloid-derived suppressor cells (MDSC) inhibit the anti-tumor immune response and promote the development and progression of OC. Platelets are also involved in immune evasion by interaction with tumor cells or through the secretion of a variety of growth factors and cytokines to promote tumor growth and angiogenesis. In this review, we discuss the role and contribution of immune cells and platelets in TME. Furthermore, we discuss their potential prognostic significance to help in the early detection of OC and to predict disease outcome.