Expression of chemokine receptors on peripheral blood T cells in children with chronic kidney disease

Dysregulated phosphate metabolism in autism spectrum disorder: associations and insights for future research

Studies of autism spectrum disorder (ASD) related to exposure to toxic levels of dietary phosphate are lacking. Phosphate toxicity from dysregulated phosphate metabolism can negatively impact almost every major organ system of the body, including the central nervous system. The present paper used a grounded theory-literature review method to synthesise associations of dysregulated phosphate metabolism with the aetiology of ASD. Cell signalling in autism has been linked to an altered balance between phosphoinositide kinases, which phosphorylate proteins, and the counteracting effect of phosphatases in neuronal membranes. Glial cell overgrowth in the developing ASD brain can lead to disturbances in neuro-circuitry, neuroinflammation and immune responses which are potentially related to excessive inorganic phosphate. The rise in ASD prevalence has been suggested to originate in changes to the gut microbiome from increasing consumption of additives in processed food, including phosphate additives. Ketogenic diets and dietary patterns that eliminate casein also reduce phosphate intake, which may account for many of the suggested benefits of these diets in children with ASD. Dysregulated phosphate metabolism is causatively linked to comorbid conditions associated with ASD such as cancer, tuberous sclerosis, mitochondrial dysfunction, diabetes, epilepsy, obesity, chronic kidney disease, tauopathy, cardiovascular disease and bone mineral disorders. Associations and proposals presented in this paper offer novel insights and directions for future research linking the aetiology of ASD with dysregulated phosphate metabolism and phosphate toxicity from excessive dietary phosphorus intake.

Chemokine receptors on peripheral blood T lymphocytes in children on peritoneal dialysis

BACKGROUND

Immune cell dysfunction is listed among complications resulting from chronic kidney disease (CKD). It could be associated with T-cells, which play a role in the lymphocytic migration and infiltration. However, the data on chemokine receptors expression on T-cells in patients with CKD particularly treated with peritoneal dialysis (PD) are still limited.

METHODS

The study aimed at multiparameter flow-cytometric analysis of the absolute numbers and percentage of T-cell subsets with surface chemokine receptors (CCR4, CCR5, CCR7, CXCR3, and CXCR4) or receptors' combinations in 47 children treated with PD.

RESULTS

We found lower absolute numbers of total T lymphocytes, lymphocytes with surface CCR5, CXCR4⁺CCR5, CXCR3⁺CCR5 antigens and T-cells with CCR4, CCR4⁺CD4, CXCR3, CXCR3⁺CD4, and CD8 receptors. Lymphocytes T with CD4, CCR7, CD28⁺CCR7, CXCR3⁺CD8 antigens showed higher percentage in children on PD as compared to healthy children and opposite percentage values of CCR4⁺, CCR4⁺CD4⁺, CXCR3⁺ T lymphocytes were diminished. Mean fluorescent intensity for CCR7⁺, CCR7⁺CD45RO⁺, CCR7⁺CD28⁺, CXCR4⁺CD4⁺, CCR5⁺CD4⁺, CCR4⁺, CCR4⁺CD4⁺ T-cells was lower in the PD group than in healthy children. The analysis of correlation between T lymphocyte subpopulations with chemokine receptors and other parameters revealed positive correlation of CCR7⁺ and CCR7⁺CD28⁺ T-cells and weekly creatinine clearance, negative correlation between the percentage of CD45RO⁺CCR7 antigen positive T-cells and KT/V_urea.

SUMMARY

In conclusion, we could not confirm the phenomenon of earlier senescence of T-cells in children with CKD on PD treatment. This still requires further investigation. The higher percentage of T-cells with CCR7 surface receptor could be responsible for the increase of proliferation activity in this group of children.

Stromal Cell-derived Factor-1 and CXC Chemokine Receptor Type-4 are Associated with Cardiovascular Disease in Patients under Hemodialysis

Background

Cardiovascular disease (CVD) is the most common cause of death among patients with end-stage renal disease especially whom under hemodialysis (HD). Stromal cell-derived factor-1 (SDF-1) and its receptor CXC chemokine receptor type-4 (CXCR4) could contribute to CVD. The main aim of this study was to evaluate the association between SDF-1 and CXCR4 with CVD and its related risk factors in patients under HD.

Methods

Sixty patients under HD and 29 healthy subjects were recruited in the study. The serum levels and relative messenger RNA (mRNA) expressions of SDF-1 and CXCR4 were measured using enzyme-linked immunosorbent assay and real-time polymerase chain reaction in patients and controls, respectively. CVD history of the patients was obtained.

Results

Twenty patients (33.3%) had a history of CVD. The mean levels of serum and relative mRNA expressions of SDF-1 and CXCR4 were higher in patients than controls and also in patients with a history of CVD than patients without it. The serum levels and relative expressions of SDF-1 and CXCR4 were positively correlated with blood urea nitrogen, parathyroid hormone, and high-sensitivity C-reactive protein and inversely correlated with hemoglobin. The history of CVD was the independent predictor of serum levels of SDF-1 and CXCR4 and also relative mRNA expression of CXCR4.

Conclusions

The higher levels of serum and relative mRNA expressions of SDF-1 and CXCR4 were associated with CVD in patients under HD. Furthermore, SDF-1 and CXCR4 were associated with several traditional and uremia-related CVD risk factors in such patients.

Immunological Alterations due to Hemodialysis Might Interfere with Early Complications in Renal Transplantation

Background

Chronic or intercurrent alterations of the immune system in patients with end-stage renal disease (CKD) and intermittent hemodialysis (CKD5D, HD) have been attributed to an acute rejection of renal allograft.

Methods

Leukocyte subsets in flow cytometry, complement activation, and concentrations of TGFβ, sCD30 (ELISA), and interleukins (CBA) of fifteen patients eligible for renal transplantation were analyzed before, during, and after a regular HD.

Results

Before HD, the median proportion of CD8+ effector cells, CD8+ CCR5+ effector cells, and HLA-DR+ regulatory T cells as well as the median concentration of soluble CD30 increased and naive CD8+ T cells decreased. During HD, there was a significant decrease in CD4- CD8- T cells (p < 0.001) and an increase in CD25+ T cells (p = 0.026), sCD30 (p < 0.001), HLA-DR+ regulatory T cells (p = 0.005), and regulatory T cells (p = 0.003). TGFβ and sCD30 increased significantly over time. The activity of the classical complement pathway started to slightly increase after the first hour of HD and lasted until fifteen minutes after finishing dialysis. The decrease in the functional activity of the alternative pathway was only transient and was followed by a significant increase within 15 minutes after finishing the treatment.

Conclusion

HD might interact with the allograft outcome by influencing T cell subsets and activation of the complement system in a biphasic course.