The Humoral Immune Response to BNT162b2 Vaccine Is Associated With Circulating CD19+ B Lymphocytes and the Naïve CD45RA to Memory CD45RO CD4+ T Helper Cells Ratio in Hemodialysis Patients and Kidney Transplant Recipients.

Background: The humoral and cellular immune responses to SARS-COV-2 vaccination remain to be elucidated in hemodialysis (HD) patients and kidney transplant recipients (KTRs), considering their baseline immunosuppressed status. The aim of our study was to assess the associations of vaccine-induced antibody responses with circulating lymphocytes sub-populations and their respective patterns of alterations in maintenance HD patients and KTRs. Materials and Methods: We included 34 HD patients and 54 KTRs who received two doses of the mRNA-vaccine BNT162b2. Lymphocyte subpopulations were analyzed by flow cytometry before vaccination (T0), before the second vaccine dose (T1) and 2 weeks after the second dose (T2). The anti-SARS-CoV2 antibody response was assessed at T1 and at T2. Results: 31 HD patients (91.8%) and 16 KTRs (29.6%) became seropositive at T2. HD patients who became seropositive following the first dose displayed higher CD19+ B lymphocytes compared to their seronegative HD counterparts. A positive correlation was established between CD19+ B cells counts and antibody titers at all time-points in both groups (p < 0.001). KTRs showed higher naïve CD4+CD45RA+ T helper cells compared to HD patients at baseline and T2 whereas HD patients displayed higher memory CD45RO+ T cells compared to KTRs at T2. The naïve CD4+CD45RA to memory CD4+CD45RO+ T helper cells fraction was negatively associated with antibody production in both groups. Conclusions: Our study provides a potential conceptual framework for monitoring vaccination efficacy in HD patients and KTRs considering the correlation established between CD19+ B cells, generation of memory CD4+ T helper cells and anti SARS-CoV2 antibody response to vaccination.

A case of encapsulating peritoneal sclerosis presented shortly after renal transplantation.

Encapsulating peritoneal sclerosis (EPS) is a rare but serious complication of peritoneal dialysis (PD), characterized by extensive intraperitoneal fibrosis and encasement of bowel loops. It typically associates with long-term PD and progressive loss of ultrafiltration. The management of EPS has evolved substantially from the original report of this entity and now includes immunosuppressive agents, antifibrotic agents, nutritional support, and surgical intervention. Although the exact cause of this condition remains obscure and despite the possible positive effect of immunosuppression on EPS, it has been described in the post-transplant setting upon the discontinuation of PD. We report such a case of a former PD patient who presented with EPS a month after renal transplantation. This article will highlight the current views regarding the management of post-transplant EPS and introduce the problem of long-term PD patients on the deceased-donor transplant waiting list.

Compositional lipoprotein changes and low-density lipoprotein susceptibility to oxidation in chronic renal failure patients with heavy proteinuria.

BACKGROUND: There are limited data regarding qualitative lipoprotein abnormalities in undialysed uremic patients without proteinuria. In this report, we focused on lipoprotein changes observed in uremic patients with proteinuria as well as on the susceptibility of low-density lipoprotein (LDL) of these patients to oxidative modification in vitro. METHODS: 20 patients with chronic renal failure [serum creatinine >1.6 mg/dl (141.4 micromol/l)], but not yet on renal replacement therapy, and with heavy proteinuria (>2 g/24 h), and 18 age- and sex-matched healthy individuals participated in the study. In both patients and controls, venous blood was collected for determination of serum lipid and lipoprotein levels, lipoprotein subfraction profile and chemical composition, as well as the susceptibility of LDL subfractions to oxidation. RESULTS: Patients exhibited a more atherogenic lipid profile compared with the control population. Furthermore, the total very LDL + intermediate-density lipoprotein mass was increased in patients compared with controls, while this subfraction was triglyceride enriched in uremic patients. The total LDL concentration was significantly higher in patients compared with controls due mainly to an increase in the mass of all lipoprotein subfractions. It is noteworthy that the mass of small dense LDL was significantly elevated in patients compared with controls (135 +/- 12 vs. 115 +/- 11 mg/dl, p = 0.01), an increase which was more pronounced in hypertriglyceridemic patients. Furthermore, the subfraction high-density lipoprotein-2 mass was significantly lower in uremic patients compared with controls. Finally, no significant differences in the lag time, the rate of oxidation and the relative electrophoretic mobility values in each LDL subfraction between the two groups were observed. CONCLUSION: We conclude that uremic patients with heavy proteinuria exhibit compositional lipoprotein changes that are less marked than those observed in nonuremic patients with nephrotic syndrome. However, there is no evidence that circulating LDL isolated from these patients is more susceptible to oxidation in vitro than lipoprotein isolated from age- and gender-matched controls.