Evaluation of Regulatory B Cell Subpopulations CD24++CD38++, CD24++CD27+, Plasmablasts and Their Correlation with T Regs CD3+CD4+CD25+FOXP3+ in Dialysis Patients and Early Post-Transplant Rejection-Free Kidney Recipients.

Background: B and T regulatory cells, also known as Bregs and Tregs, are involved in kidney transplantation. The purpose of this study is to monitor changes in the frequency and absolute numbers of Tregs (CD3+CD4+CD25+FoxP3+), transitional Bregs (tBregs) (CD24++CD38++), memory Bregs (mBregs) (CD24++CD27+), and plasmablasts before (T0) and six months (T6) after transplantation. Additionally, we aim to investigate any correlation between Tregs and tBregs, mBregs, or plasmablasts and their relationship with graft function. Methods: Flow cytometry was used to immunophenotype cells from 50 kidney recipients who did not experience rejection. Renal function was assessed using the estimated glomerular filtration rate (eGFR). Results: At T6, there was a significant decrease in the frequency of Tregs, plasmablasts, and tBregs, as well as in the absolute number of tBregs. The frequency of mBregs, however, remained unchanged. Graft function was found to have a positive correlation with the frequency of tBregs and plasmablasts. A significant correlation was observed between the frequency and absolute number of tBregs only when the eGFR was greater than 60 but not at lower values. At an eGFR greater than 60, there was a positive correlation between the absolute numbers of Tregs and mBregs but not between Tregs and tBregs. No correlation was observed for any cell population in dialysis patients. Conclusions: The data show a correlation between the frequency and absolute number of tBregs and the absolute number of Tregs and mBregs with good renal function in the early post-transplant period.

Exploring Perturbations in Peripheral B Cell Memory Subpopulations Early after Kidney Transplantation Using Unsupervised Machine Learning.

BACKGROUND: B cells have a significant role in transplantation. We examined the distribution of memory subpopulations (MBCs) and naïve B cell (NBCs) phenotypes in patients soon after kidney transplantation. Unsupervised machine learning cluster analysis is used to determine the association between the cellular phenotypes and renal function. METHODS: MBC subpopulations and NBCs from 47 stable renal transplant recipients were characterized by flow cytometry just before (T0) and 6 months after (T6) transplantation. T0 and T6 measurements were compared, and clusters of patients with similar cellular phenotypic profiles at T6 were identified. Two clusters, clusters 1 and 2, were formed, and the glomerular filtration rate was estimated (eGFR) for these clusters. RESULTS: A significant increase in NBC frequency was observed between T0 and T6, with no statistically significant differences in the MBC subpopulations. Cluster 1 was characterized by a predominance of the NBC phenotype with a lower frequency of MBCs, whereas cluster 2 was characterized by a high frequency of MBCs and a lower frequency of NBCs. With regard to eGFR, cluster 1 showed a higher value compared to cluster 2. CONCLUSIONS: Transplanted kidney patients can be stratified into clusters based on the combination of heterogeneity of MBC phenotype, NBCs and eGFR using unsupervised machine learning.

Tubular Pyloric Gland Adenoma of the Left and Right Hepatic Ducts: Report of a Unique Case With Immunohistochemical and Molecular Studies.

Pyloric gland adenomas (PGAs) of the extrahepatic biliary system are rare lesions. We report a case of a tubular PGA that led to biliary obstruction. The tumor was located at the confluence of the right and left hepatic ducts, extending to the left hepatic duct. The tumor cells expressed MUC6 and MUC5AC. MUC1 and CD10 were focally positive. MUC2, p53, and CDX2 were not expressed. The Ki67 positivity was estimated at <15%. None of the KRAS, NRAS, BRAF, EGFR coding regions resulted in clinically relevant amino acid substitutions. SNP rs1050171 (EGFR p.Q787Q, silent mutation) corresponding to c.2361G>A transition in exon 20 was noticed. Awareness of this rare lesion is important for pathologists and clinicians alike, because it may cause significant morphologic and clinical difficulties, especially when presenting as an obstructive mass. Because of the possible risk of evolving malignancy, surgical resection is recommended whenever possible.

Hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is a heterogeneous tumor with many factors implicated in its development, with chronic infection and cirrhosis by hepatitis B virus (HBV) being the most prevalent. Cirrhosis due to metabolic syndrome, alcohol consumption, viral infection with hepatitis C virus (HCV) is also involved in its development. Treatment of HCC remains unsatisfactory. Therapeutic management for HCC includes liver transplantation, liver resection, ablation, chemoembolization, which depend on the tumor stage, liver function, and patient performance status. The involvement of different signaling pathways in the initiation and modulation of HCC development based on clinical and research data provided a strong rationale for the development of anti-cancer agents targeting key components of the pathways. The complexity of the tumor prevents the major goal of this therapeutic approach, since sorafenib, a multi-kinase inhibitor, is the only successful drug so far that belongs to the target directed therapy in advanced stage HCC.

Molecular epidemiology of chronic hepatitis B virus infection in Greece.

Virological data on chronic hepatitis B virus (HBV) infection in Greece are limited. HBV genotypes, surface antigen (HBsAg) subtypes, and HBsAg "a" determinant mutations among patients infected chronically with HBV, were investigated. Serum samples from 135 HBsAg positive patients were tested. Serologic (HBsAg, anti-HBs, HBeAg, and anti-HBe), virologic (HBV-DNA quantitation) and biochemical markers (serum alanine aminotransferase/ALT and aspartate aminotransferase/AST) were analyzed. HBV genotypes and HBsAg subtypes were determined by partial sequencing of the S gene. Genotyping was performed by using the National Center for Biotechnology Information online Genotyping tool and phylogenetic analysis. Nucleotide sequences were aligned pair wise with ClustalW and phylogenetic trees were constructed by the neighbor-joining method. Sequences were also used to predict HBV HBsAg subtypes. In six patients (4%), simultaneous presence of HBsAg and anti-HBs was determined, whereas 47 patients (35%) were HBeAg positive, 84 (62.5%) were anti-HBe positive, and four patients (3%) were characterized by the simultaneous presence of HBeAg and anti-HBe. Mean ALT was 238 IU/L (standard deviation = 576.84), and HBV-DNA levels ranged from 1.02 × 10(5) to 2.2 × 10(7) IU/ml. Genotype D was predominant (98%), with viral groups D/ayw2 (73%) and D/ayw3 (27%). Group A/adw accounted for 1% of cases. Genotypes B and C were found exclusively in the Chinese immigrants (1%). Single or multiple point mutations were found in 35 cases (26%). Some of the most common mutations occurred at amino acid positions 129, 133, 134, 144, 145, including the "vaccine escape" mutation G145R. Mutations analysis revealed that amino acid substitutions did not affect detection by commercial immunoassays.

Cyclosporine a augments P-glycoprotein expression in the regenerating rat liver.

In the liver, the multidrug resistance (MDR) protein P-glycoprotein (P-gp) is physiologically expressed at the bile canalicular membrane, where it participates in the biliary excretion of various lipophilic drugs and xenobiotics. Previous studies showed that the immunosuppressive agent cyclosporine A (CsA) modulates P-gp and exerts a hepatotrophic influence in the regenerating liver. Hepatocytes isolated from regenerating rat liver, after 2/3 partial hepatectomy (PH 2/3), were used as an in vivo experimental model of cells with high proliferating activity in order to investigate whether CsA influences cellular levels of P-gp in those cells. Male Wistar rats were treated with CsA (20 mg/kg body weight) for 4 d preoperatively and 1 d postoperatively, and regenerating hepatocytes were isolated by collagenase perfusion 12, 24 and 48 h after PH 2/3. Flow cytometry and Western blotting studies with the monoclonal antibodies C494 and C219 showed that after PH 2/3, cellular levels of P-gp were initially suppressed, 12 h after PH 2/3, by 23%, but were significantly elevated thereafter, 24 and 48 h after PH 2/3 by 28% and 73%, respectively. In CsA pretreated animals, P-gp levels were increased even in normal hepatocytes by 34%, and an additional augmentation was seen in hepatocytes from 24 and 48 h regenerating livers (60% and 56%, respectively). In summary, we demonstrate for the first time that CsA has an additive effect on the expression of P-glycoprotein during liver regeneration in the rat. Therefore, induction of P-gp might also be considered in patients receiving CsA after liver transplantation for hepatocellular carcinoma and chemotherapy as an adjuvant treatment for the prevention of tumor recurrence.