THE EFFECT OF EPIDERMAL GROWTH-FACTOR ON BACTERIAL TRANSLOCATION IN NEWBORN RABBITS

Purpose: Epidermal growth factor (EGF), which is present in breast mil k, has both trophic and maturational effects on intestinal mucosa. The aim of this study is to determine the effect of EGF on spontaneous in testinal bacterial translocation (BT) in formula-fed newborn rabbits, who have a high incidence of BT compared with breast-fed newborn rabbi ts. Methods: Sixty-one rabbit pups were divided into three groups: EGF (-), n = 24, EGF(+), n = 22, and breast-fed animals, n = 15. Both the EGF(-) and EGF(;) groups were gavage fed a standard artificial formula three times daily. EGF was administered subcutaneously three times da ily (1.5 ug/g body weight per day) in the EGF(+) group. The breast-fed group was fed by their mothers ad libitum. At 7 days of age, all rabb its were killed, and the mesenteric lymph nodes (MLN), liver, and sple en were cultured qualitatively for bacterial growth, while the cecum a nd ileum were quantitatively cultured. To determine the effect of EGF on mucus-producing cells, goblet cell numbers in the small intestine w ere quantified histologically. Results: There was no BT to MLN, spleen , or liver in the breast-fed group. The incidence of BT to MLN and spl een was significantly lower in the EGF(+) compared with EGF(-) group; (EGF[+]: MLN, 45%; spleen, 32%; Liver, 27%; EGF[-]: MLN, 79%; Spleen 6 7%; Liver 29%; in EGF[+] MLN and Spleen P<.05 vEGF[-]). There was no s ignificant difference in cecal and ileal bacterial colonization betwee n the EGF(+) and EGF(-) groups. The number of goblet cells in the smal l intestine was significantly lower in the EGF(-) group compared with the EGF(+) group as follows: EGF(+), 14 +/- 3; EGF(-), 9 +/- 3; breast -fed, 11 +/- 5 goblet cells per 100 epithelial cell nuclei; P=.013. Co nclusions: (1) EGF caused a significant decrease in spontaneous bacter ial translocation in formula-fed newborn rabbits and was associated wi th an increase in the goblet cell number of the small intestine. (2) T hese changes occurred in spite of the fact that no changes in small bo wel bacterial colonization were observed. (3) These results suggest, b ut do not prove, that EGF may provide protection for neonates from gut origin infection by improving the mucosal barrier function through in creased goblet cell production, thus decreasing the incidence of spont aneous bacterial translocation in the newborn. Copyright (C) 1998 by W .B. Saunders Company.