title: [B lymphocyte clonal evolution of human reactive lymph nodes revealed by lineage tree analysis].
abstract: BACKGROUND
  Hypermutation and selection processes, characterizing T-dependent B cell responses taking place in germinal centers of lymph nodes, lead to B cell receptor affinity maturation. Those immune responses lead to the development of memory B cells and plasma cells that secrete high amounts of antibody molecules. The dynamics of B cell clonal evolution during affinity maturation has significant importance in infectious and autoimmune diseases, malignancies and aging. Immunoglobulin (Ig) gene mutational Lineage tree construction by comparing variable regions of Ig-gene sequences to the Ig germline gene is an interesting approach for studying B cell cLonal evolution. Lineage tree shapes and Ig gene mutations can be evaluated not only qualitatively and intuitively, but also quantitatively, and thus reveal important information related to hypermutation and selection.
  
  
  OBJECTIVE
  In this paper we describe the experimental protocols that we used for PCR amplification of Igvariable region genes from human formalin fixed paraffin embedded reactive lymph node tissues and the subsequent bioinformatical analyses of sequencing data using Ig mutational lineage trees.
  
  
  RESULTS
  B cell populations of three out of four reactive Lymph node tissues were composed of several clones. Most of the Ig gene mutational lineage trees were small and narrow. Significant differences were not detected by quantification of Lineage trees.
  
  
  CONCLUSIONS
  B lymphocyte clones that were detected in human reactive lymph node tissues represent major responding clones in normal polyclonal immune response. This result is in line with the polyclonal profile of B Lymphocyte populations that reside in reactive lymph node tissues.
authors.affiliation: Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel. hillatk73@gmail.com
authors.forename: Hilla
authors.initials: H
authors.lastname: Tabibian-Keissar
authors.forename: Ginette
authors.initials: G
authors.lastname: Schiby
authors.forename: Noemie
authors.initials: N
authors.lastname: Azogui-Rosenthal
authors.forename: Helena
authors.initials: H
authors.lastname: Hazanov
authors.forename: Aviya Shapira
authors.initials: AS
authors.lastname: Rakovsky
authors.forename: Miri
authors.initials: M
authors.lastname: Michaeli
authors.forename: Kinneret
authors.initials: K
authors.lastname: Rosenblatt
authors.forename: Ramit
authors.initials: R
authors.lastname: Mehr
authors.forename: Iris
authors.initials: I
authors.lastname: Barshack
mesh_terms: D001402:B-Lymphocytes / Q000276:immunology*; D019070:Cell Lineage; D002999:Clone Cells / Q000276:immunology; D005784:Gene Amplification; D006801:Humans; D007135:Immunoglobulin Variable Region / Q000235:genetics*; D008198:Lymph Nodes / Q000276:immunology*; D016133:Polymerase Chain Reaction / Q000379:methods; D017422:Sequence Analysis, DNA
chemical_list: D007135:Immunoglobulin Variable Region