ROLE OF GLUTAMINE IN THE IMMUNE-RESPONSE IN CRITICAL ILLNESS

The dependence of human lymphocyte functions on the exogenous provisio n of glutamine (GLN) was evaluated in a series of in vitro experiments . The transcription of early activation markers (IL-2, IL-2-receptor, IL-4, IL-4, GM-CSF, IFN gamma) as evaluated by polymerase chain reacti on was observed even in the absence of exogenous GLN. In contrast, lat er events of lymphocyte activation including cytokine production, prol iferation of lymphocytes and lymphokine-activated killer cell activity were found to depend on exogenous GLN provision. These in vitro resul ts are discussed in the context of established data on the reduction o f peripheral blood GLN concentrations in critically ill patients and i n view of recent studies reporting improved outcome of critically ill patients following GLN substitution. By and large, these data support the concept of GLN substitution in critical illness. However, the defi nition of indications and dose-response relationships clearly require further clinical studies.