Enteral feeding preserves gut Th-2 cytokines despite mucosal cellular adhesion molecule-1 blockade.
BACKGROUND
Parenteral nutrition (PN) decreases gut-associated lymphoid tissue (GALT), the intestinal IgA stimulating cytokines IL-4 and IL-10 in gut homogenates, intestinal IgA levels and the expression of Peyer patch (PP) mucosal cellular adhesion molecule-1 (MAdCAM-1), an adhesion molecule found on the high endothelial venules of PP and other tissues. IL-4 in PP stimulates MAdCAM expression in vitro. MAdCAM-1 blockade with MECA-367 reduces GALT cell populations to PN levels but maintains intestinal IgA levels if the animals are chow fed. This study compares IL-4 levels in PP of chow and PN fed mice and measures the effects of MAdCAM blockade on IL-4 and IL-10 levels in gut homogenates of chow fed mice. We hypothesized that in vivo IL-4 levels drop in PP of PN fed mice and IL-4 and IL-10 levels are maintained after MAdCAM-1 blockade in chow fed mice.


METHODS
Exp 1: 18 mice received chow or PN for 5 days to determine PP IL-4 levels. Exp 2: 44 mice were randomized to chow + control monoclonal antibody (mAb), chow + MECA-367 (anti-MAdCAM-1 mAb) or PN for 4 days before measurement of IL-4 and IL-10 levels in gut homogenates.


RESULTS
Exp 1: IL-4 levels in vivo were lower in PP of PN-fed mice than chow fed mice (92.0 +/- 15.1 pg/mL vs 251.1 +/- 14.8, p = .0003). Exp 2: IL-4 levels were significantly higher in chow + control mAb (187.1 +/- 44.1 pg/mL) and chow + MECA-367 (110.9 +/- 19.1 pg/mL) groups than PN mice (21.8 +/- 30.6 pg/mL, p < .02 vs chow + control or chow + MECA-367). IL-10 levels were significantly lower with PN (23.1 +/- 40.9 pg/mL) with chow+control (174.0 +/- 22.2 pg/mL p < .01), or chow + MECA-367 (181.7 +/- 23.1 pg/mL, p < .02 vs PN).


CONCLUSIONS
PN-feeding reduces in vivo IL-4 levels in PP (consistent with lowered MAdCAM-1 expression) and IL-4 and IL-10 levels in gut homogenates compared with chow. Despite MAdCAM-1 blockade, enteral feeding preserved gut IL-4 levels and increased IL-10 levels consistent with preserved IgA levels.
Genton
Laurence
L
Veterans Administration Surgical Services, William S. Middleton Memorial Veterans Hospital Madison, Wisconsin, USA.
Kudsk
Kenneth A
KA
Reese
Shannon R
SR
Ikeda
Shigeo
S
D000818:Animals; D000911:Antibodies, Monoclonal / Q000008:administration & dosage*; D015815:Cell Adhesion Molecules; D004750:Enteral Nutrition; D018928:Immunity, Mucosal / Q000276:immunology*; D007070:Immunoglobulin A / Q000378:metabolism; D007136:Immunoglobulins / Q000276:immunology*; D016753:Interleukin-10 / Q000096:biosynthesis*; D015847:Interleukin-4 / Q000096:biosynthesis*; D007413:Intestinal Mucosa / Q000276:immunology; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009088:Mucoproteins / Q000037:antagonists & inhibitors / Q000276:immunology*; D010288:Parenteral Nutrition / Q000009:adverse effects; D010581:Peyer's Patches / Q000378:metabolism*; D011897:Random Allocation
D000911:Antibodies, Monoclonal; D015815:Cell Adhesion Molecules; D007070:Immunoglobulin A; D007136:Immunoglobulins; C489082:Madcam1 protein, mouse; D009088:Mucoproteins; D016753:Interleukin-10; D015847:Interleukin-4