Early Investigation of the Gut–Lymph Concept

The presence of intestinal ischemia alters the composition of enteral lymph and these alterations can modify the development of organ dysfunction and associated inflammatory changes.^1–4 Although preclinical investigation of these phenomena has been relatively accessible, translation to the context of human pathology is rendered difficult through the inherent barriers to sampling human thoracic duct lymph.

In this issue of Lymphatic Research and Biology, Escott and his colleagues have advanced a pilot technique that consists of intraoperative cannulation of the human thoracic duct with delayed embolization. This permits objective serial quantitation of the thoracic duct lymph pressure. The authors describe the ability to analyze lymph flow and composition in response to enteral feeding as well as to vasopressor administration.

The current investigation has facilitated the analysis of three of the four patients in whom the procedure was attempted. The authors observed significant enhancement over plasma concentration of several of the measured contents of thoracic duct lymph, including lipase, interleukin-6, tumor necrosis factor-α, d-lactate, endotoxin, and intestinal fatty binding protein. These observations suggest that intestinal ischemia can be exacerbated by nonselective vasopressor administration. The authors note that, although the lymph composition altered in a time-dependent manner, and in response to feeding and vasopressor administration, there was no concurrent change in thoracic duct flow rates.

The gut–lymph concept remains, as yet, in its infancy, but the current report suggests that exciting observations lie ahead. Explication of these vascular and molecular phenomena is destined to provide insights that can be implemented in the maintenance and restoration of human health.