title: Continuous ambulatory peritoneal dialysis impairs T lymphocyte selection in the peritoneum.
abstract: Peritoneal lymphocytes (PCL) of 45 healthy individuals, four uremic patients with end-stage renal disease (ESRD) and 25 long-term continuous ambulatory peritoneal dialysis (CAPD) patients were characterized by flow cytometry to investigate whether CAPD alters the phenotype of PCL. B lineage cells constitute a minority of PCL (2.5% of cells). Although the majority of peritoneal T cells expressed alpha beta T cell receptor (TcR), 7% expressed gamma delta TcR, a proportion which was significantly higher than that in peripheral blood (PBMC) (approximately 4%). The majority of PCL T cells exhibited markers of the thymus-dependent lineage (CD2, CD3, TcR alpha beta, CD8 alpha beta or CD4) and surface antigens associated with memory and activation (CD45RO, CD11a, CD18, CD49d, HLA-DR). An average of 75% of both CD4+ and CD8+ PCL T cells of healthy subjects and CAPD patients were CDw60+, thus characterizing the T cell subset containing the helper activity for the mitogen-driven B cell differentiation. CD44s was abundantly expressed on PCL T cells. In contrast to PCL T cells of healthy subjects peritoneal T lymphocytes of CAPD patients exhibited CD44 splice variants containing products of exon-v9 and the proportion of CD44v9+ cells correlated with the frequency of peritonitis episodes the patients had gone through. The majority of PCL T cells of both healthy subjects and CAPD patients were CD8+. A large proportion of CD8+ PCL T cells from healthy subjects expressed the homodimeric CD8 alpha alpha isoform; however, such cells were not found in CAPD patients. In healthy subjects mRNA for the recombination activating gene 1 (RAG-1) was detectable in a PCL population containing CD7-CD34+ and CD7+CD34+ cells. In contrast, neither mRNA transcripts of the RAG-1 gene nor CD34+ cells were detectable in PCL of CAPD patients.
authors.affiliation: Department of Medicine, Ludwig-Maximilians-University Munich, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Fricke
authors.forename: J
authors.initials: J
authors.lastname: Hartmann
authors.forename: T
authors.initials: T
authors.lastname: Sitter
authors.forename: R
authors.initials: R
authors.lastname: Steldinger
authors.forename: P
authors.initials: P
authors.lastname: Rieber
authors.forename: H
authors.initials: H
authors.lastname: Schiffl
mesh_terms: D000328:Adult; D000368:Aged; D015703:Antigens, CD / Q000235:genetics; D000945:Antigens, Differentiation, T-Lymphocyte / Q000235:genetics; D001202:Ascitic Fluid / Q000276:immunology* / Q000473:pathology; D001483:Base Sequence; D016827:CD8 Antigens / Q000235:genetics; D017931:DNA Primers / Q000235:genetics; D005260:Female; D005434:Flow Cytometry; D018398:Homeodomain Proteins; D006801:Humans; D018960:Hyaluronan Receptors / Q000235:genetics; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D010531:Peritoneal Dialysis, Continuous Ambulatory / Q000009:adverse effects*; D010537:Peritoneum / Q000276:immunology*; D010641:Phenotype; D011506:Proteins / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016176:T-Lymphocyte Subsets / Q000276:immunology* / Q000378:metabolism / Q000473:pathology
chemical_list: D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D016827:CD8 Antigens; C064741:CDw60 antigen; D017931:DNA Primers; D018398:Homeodomain Proteins; D018960:Hyaluronan Receptors; D011506:Proteins; D012333:RNA, Messenger; C064658:RAG-1 protein