Background: Total parenteral nutrition (TPN) is associated with deplet
ion of intestinal immune cells and increased gut permeability (GP). Ad
ding glutamine (GLN) to TPN preserves GP by an unknown mechanism. Inte
stinal immune cells situated between the enterocytes (intraepithelial
lymphocytes, [IEL]) influence GP in vitro. To obtain insight into the
underlying mechanism of GLN on GP, we investigated the effects of GLN-
supplemented TPN on IEL, immunoglobulin A (IgA) plasma cells and goble
t cells, and enterocyte proliferation in intestinal biopsies. Methods:
Twenty patients randomly received GLN-enriched TPN (GT) or isonitroge
nous standard TPN (ST). Proliferation and number of immune cells were
measured in intestinal biopsies obtained before and after 10 days of T
PN. Results: No change in proliferative activity or in number of IgA p
lasma cells was observed. Goblet cells increased in the ST group, wher
eas the change seen in the GT group did not reach significance. In the
GT group, IEL decreased, whereas in the ST group, no change in the nu
mber of IEL was observed. Conclusions: TPN was not associated with cha
nges in proliferative activity or with depletion of gut immune cells.
The data indicate that GLN-supplemented TPN has a different effect on
intestinal immune cells compared with standard TPN.