Regional blood flow and the localisation of lymphoblasts in the small intestine of the mouse: effect of an elemental diet.

To test the hypothesis that food antigens influence the in vivo migration of lymphoblasts to the small intestine, the effect of an elemental diet (Vivonex) on the distribution of lymphoblasts within the small intestine of mice has been examined. Viable lymphoblasts from the mesenteric nodes of conventionally fed animals were labelled in vitro and given intravenously to recipient mice fed either a standard diet or elemental diet. The localisation of these cells within the small intestine was altered in the animals fed the elemental diet but only in the distal half of the small intestine. The relationship of the localisation of blast cells to the delivery of cardiac output along the small intestine was examined by assessing cell localisation in conjunction with the distribution of an isotopic indicator (86RbC1). The results show that the pattern of localisation of lymphoblasts within the small intestine is related to the probability that they will be delivered to different regions by the blood stream. Therefore, the alterations in blast localisation in the small intestine of animals of the elemental diet can be viewed as a consequence of changes in the perfusion of the distal small intestine. These results do not support the concept that antigens directly influence the efficiency with which blast cells migrate into the intestinal mucosa.