title: Defective proliferative responses in B lymphocytes and thymocytes that lack neurofibromin.
abstract: Nf1(-/-) fetal liver cells were used to reconstitute B and T cells in Rag-1(-/-) mice. Lymphocyte development was largely unimpaired in the absence of neurofibromin. However antigen-receptor induced proliferation was defective in neurofibromin deficient peripheral B cells and CD4(+) single positive thymocytes. In contrast to its role as a negative regulator of proliferation in many other cell types, neurofibromin may be a positive regulator of lymphocyte proliferation. Peripheral B cells exhibited circumscribed defects in anti-IgM induced protein tyrosine phosphorylation, which may contribute to the unexpected proliferative defect seen in these cells.
authors.affiliation: Cancer Center, Massachusetts General Hospital, Building 149, 13th Street, Charlestown Navy Yard, Boston, MA 02129, USA.
authors.forename: Tae Jin
authors.initials: TJ
authors.lastname: Kim
authors.forename: Annaiah
authors.initials: A
authors.lastname: Cariappa
authors.forename: John
authors.initials: J
authors.lastname: Iacomini
authors.forename: Mei
authors.initials: M
authors.lastname: Tang
authors.forename: Shane
authors.initials: S
authors.lastname: Shih
authors.forename: Andre
authors.initials: A
authors.lastname: Bernards
authors.forename: Tyler
authors.initials: T
authors.lastname: Jacks
authors.forename: Shiv
authors.initials: S
authors.lastname: Pillai
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000473:pathology / Q000502:physiology*; D015496:CD4-Positive T-Lymphocytes / Q000473:pathology / Q000502:physiology*; D002455:Cell Division / Q000502:physiology; D017353:Gene Deletion; D008213:Lymphocyte Activation / Q000502:physiology; D051379:Mice; D018345:Mice, Knockout; D025542:Neurofibromin 1 / Q000235:genetics / Q000502:physiology*; D015398:Signal Transduction / Q000276:immunology
chemical_list: D025542:Neurofibromin 1