title: Gut Lymphocyte Phenotype Changes After Parenteral Nutrition and Neuropeptide Administration.
abstract: OBJECTIVE
  To define gut-associated lymphoid tissue (GALT) phenotype changes with parenteral nutrition (PN) and PN with bombesin (BBS).
  
  
  BACKGROUND
  PN reduces respiratory tract (RT) and GALT Peyer patch and lamina propria lymphocytes, lowers gut and RT immunoglobulin A (IgA) levels, and destroys established RT antiviral and antibacterial immunity. BBS, an enteric nervous system neuropeptide, reverses PN-induced IgA and RT immune defects.
  
  
  METHODS
  Experiment 1: Intravenously cannulated ICR mice received chow, PN, or PN + BBS injections for 5 days. LSR-II flow cytometer analyzed Peyer patches and lamina propria isolated lymphocytes for homing phenotypes (L-selectin and LPAM-1) and state of activation (CD25, CD44) in T (CD3)-cell subsets (CD4 and CD8) along with homing phenotype (L-selectin and LPAM-1) in naive B (IgD) and antigen-activated (IgD or IgM) B (CD45R/B220) cells. Experiment 2: Following the initial experiment 1 protocol, lamina propria T regulatory cell phenotype was evaluated by Foxp3 expression.
  
  
  RESULTS
  Experiment 1: PN significantly reduced lamina propria (1) CD4CD25 (activated) and (2) CD4CD25LPAM-1 (activated cells homed to the lamina propria) T cells, whereas PN-BBS assimilated chow levels. PN significantly reduced lamina propria (1) IgD (naive), (2) IgDLPAM (antigen-activated homed to the lamina propria) and CD44 memory B cells, whereas PN-BBS assimilated chow levels. Experiment 2: PN significantly reduced lamina propria CD4CD25Foxp3 T regulatory cells compared with chow-fed mice, whereas PN + BBS assimilated chow levels.
  
  
  CONCLUSIONS
  PN reduces lamina propria activated and T regulatory cells and also naive and memory B cells. BBS addition to PN maintains these cell phenotypes, demonstrating the intimate involvement of the enteric nervous system in mucosal immunity.
authors.affiliation: *Department of Surgery, University of Wisconsin School of Medicine and Public Health, Madison, WI †Veterans Administration Surgical Services, William S. Middleton Memorial Veterans Hospital, Madison, WI.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Jonker
authors.forename: Aaron F
authors.initials: AF
authors.lastname: Heneghan
authors.forename: John H
authors.initials: JH
authors.lastname: Fechner
authors.forename: Joseph F
authors.initials: JF
authors.lastname: Pierre
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Sano
authors.forename: Jinggang
authors.initials: J
authors.lastname: Lan
authors.forename: Kenneth A
authors.initials: KA
authors.lastname: Kudsk
mesh_terms: D000818:Animals; D001839:Bombesin / Q000008:administration & dosage*; D018928:Immunity, Mucosal / Q000187:drug effects / Q000276:immunology*; D007070:Immunoglobulin A / Q000276:immunology; D007413:Intestinal Mucosa / Q000187:drug effects / Q000276:immunology*; D016131:Lymphocyte Subsets / Q000187:drug effects / Q000276:immunology*; D008297:Male; D008813:Mice, Inbred ICR; D023421:Models, Animal; D009479:Neuropeptides / Q000008:administration & dosage*; D010289:Parenteral Nutrition, Total; D010641:Phenotype; D020545:Respiratory Mucosa / Q000187:drug effects / Q000276:immunology*
chemical_list: D007070:Immunoglobulin A; D009479:Neuropeptides; D001839:Bombesin