Suppressed T helper 2 immunity and prolonged survival of a nematode parasite in protein-malnourished mice

Citation
R. Ing et al., Suppressed T helper 2 immunity and prolonged survival of a nematode parasite in protein-malnourished mice, P NAS US, 97(13), 2000, pp. 7078-7083
Citations number
32
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Multidisciplinary
Journal title
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
ISSN journal
0027-8424 → ACNP
Volume
97
Issue
13
Year of publication
2000
Pages
7078 - 7083
Database
ISI
SICI code
0027-8424(20000620)97:13<7078:STH2IA>2.0.ZU;2-X
Abstract
Protein malnutrition may increase susceptibility to gastrointestinal parasi tic infections, possibly as a result of impaired intestinal and/or systemic T helper 2 (Th2) effector responses induced by downregulation of Th2 cytok ines and/or up-regulation of Th1 cytokines, To test this hypothesis, female BALB/c mice (n = 18/diet) were fed a control (24%), marginal (7%), or defi cient(3%) protein diet and given a challenge infection with Heligmosomoides polygyrus. The 3% mice had higher worm burdens at 1, 2, and 4 weeks postch allenge infection (pci), lower increases in serum IgE, reduced intestinal e osinophilia, and depressed mucosal mast cell proliferation and activation a t 1-2 weeks pci. To determine whether these suppressed effector responses r esulted from altered spleen and mesenteric lymph node (MLN) cytokine produc tion, cells were restimulated in vitro with parasite antigen and cytokine c oncentrations were measured. Deficient MLN cells secreted significantly les s IL-4 and more IFN-gamma at 1-2 weeks pci than did control MLN cells. Defi cient spleen cells also secreted more IFN-gamma at 2 weeks pci compared wit h control spleen cells. From reverse transcription-PCR analyses, the 3% mic e also had lower IL-4 mRNA level in spleen and MLN at 1-2 weeks pci, Our st udy supports the hypothesis that protein malnutrition increases the surviva l of a nematode parasite by decreasing gut-associated IL-4 (Th2) and increa sing IFN-gamma (Th1) within 2 weeks pci, leading to reduced intestinal and systemic Th2 effector responses.