title: Partial splenectomy but not total splenectomy preserves immunoglobulin M memory B cells in mice.
abstract: OBJECTIVE
  The mechanism by which partial splenectomy preserves splenic immune function is unknown. Immunoglobulin (Ig) M memory B cells are critical for the immune response against encapsulated bacteria and are reduced in asplenic patients, although it is unknown whether partial splenectomy can preserve memory B cells. We hypothesized that IgM memory B cells (murine B-1a cells) would be preserved after partial splenectomy but not after total splenectomy in mice.
  
  
  METHODS
  We performed total splenectomy (n = 17), partial splenectomy (n = 10), or sham laparotomy (n = 16) on C57BL/6J mice. Mice were killed on postoperative day 10 or 30, and peritoneal washings were analyzed by multiparameter flow cytometry for expression of murine B-1a cells (IgM(pos)IgD(dull)CD5(pos)B220(dull)).
  
  
  RESULTS
  We found that B-1a cells were significantly reduced after both total and partial splenectomies compared with sham laparotomy in the early postoperative period, although normal levels of B-1a cells returned by postoperative day 30 in mice undergoing partial splenectomy but not total splenectomy.
  
  
  CONCLUSIONS
  Partial splenectomy but not total splenectomy preserves the B-1a B-cell population in mice within 30 days after surgery. Maintenance of these critical B cells may contribute to the preservation of a splenic-dependent immune response after partial splenectomy.
authors.affiliation: Department of Surgery, Duke University Medical Center, Durham, NC 22710, USA.
authors.forename: Elisabeth T
authors.initials: ET
authors.lastname: Tracy
authors.forename: Karen M
authors.initials: KM
authors.lastname: Haas
authors.forename: Tracy
authors.initials: T
authors.lastname: Gentry
authors.forename: Melissa
authors.initials: M
authors.lastname: Danko
authors.forename: Joseph L
authors.initials: JL
authors.lastname: Roberts
authors.forename: Joanne
authors.initials: J
authors.lastname: Kurtzberg
authors.forename: Henry E
authors.initials: HE
authors.lastname: Rice
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology*; D007075:Immunoglobulin M; D007156:Immunologic Memory; D051379:Mice; D008810:Mice, Inbred C57BL; D013156:Splenectomy / Q000379:methods*
chemical_list: D007075:Immunoglobulin M